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Sample records for surface components responsible

  1. Optimization of microwave-assisted extraction (MAP) for ginseng components by response surface methodology.

    Science.gov (United States)

    Kwon, Joong-Ho; Bélanger, Jacqueline M R; Paré, J R Jocelyn

    2003-03-26

    Response surface methodology (RSM) was applied to predict optimum conditions for microwave-assisted extraction-a MAP technology-of saponin components from ginseng roots. A central composite design was used to monitor the effect of ethanol concentration (30-90%, X(1)) and extraction time (30-270 s, X(2)) on dependent variables, such as total extract yield (Y(1)), crude saponin content (Y(2)), and saponin ratio (Y(3)), under atmospheric pressure conditions when focused microwaves were applied at an emission frequency of 2450 MHz. In MAP under pre-established conditions, correlation coefficients (R (2)) of the models for total extract yield and crude saponin were 0.9841 (p extraction conditions were predicted for each variable as 52.6% ethanol and 224.7 s in extract yield and as 77.3% ethanol and 295.1 s in crude saponins, respectively. Estimated maximum values at predicted optimum conditions were in good agreement with experimental values.

  2. 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

  3. 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

  4. Novel processing of Barkhausen noise signal for assessment of residual stress in surface ground components exhibiting poor magnetic response

    International Nuclear Information System (INIS)

    Vashista, M.; Paul, S.

    2011-01-01

    The Barkhausen Noise Analysis (BNA) technique has been utilised to assess surface integrity of steels. But the BNA technique is not very successful in evaluating surface integrity of ground steels that exhibit poor micro-magnetic response. A new approach has been proposed for the processing of BN signal and two newly proposed parameters, namely 'count' and 'event', have been shown to correlate linearly with the residual stress upon grinding, with judicious choice of user defined 'threshold', even when the micro-magnetic response of the work material is poor. In the present study, residual stress induced upon conventional plunge surface grinding of hardened bearing steel has been investigated along with unhardened bearing steel for benchmarking. Moreover, similar correlation has been established, when primarily compressive stress is induced upon high speed grinding using cBN wheel with moderately deep cut suppressing the micro-magnetic response from the ground medium carbon steel as the work material. - Highlights: → The problem of work materials exhibiting poor BN response and poor Barkhausen Noise response is identified. → A novel signal processing strategy is introduced to address the issue of poor micro-magnetic response of some ferromagnetic material. → Potential of newly introduced BN parameters has been studied. → These two BN parameters exhibited linear correlation with residual stress for work material with poor micro-magnetic response.

  5. 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.

  6. 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.

  7. 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...

  8. Optimization of Extraction Process for Antidiabetic and Antioxidant Activities of Kursi Wufarikun Ziyabit Using Response Surface Methodology and Quantitative Analysis of Main Components.

    Science.gov (United States)

    Edirs, Salamet; Turak, Ablajan; Numonov, Sodik; Xin, Xuelei; Aisa, Haji Akber

    2017-01-01

    By using extraction yield, total polyphenolic content, antidiabetic activities (PTP-1B and α -glycosidase), and antioxidant activity (ABTS and DPPH) as indicated markers, the extraction conditions of the prescription Kursi Wufarikun Ziyabit (KWZ) were optimized by response surface methodology (RSM). Independent variables were ethanol concentration, extraction temperature, solid-to-solvent ratio, and extraction time. The result of RSM analysis showed that the four variables investigated have a significant effect ( p analysis of effective part of KWZ was characterized via UPLC method, 12 main components were identified by standard compounds, and all of them have shown good regression within the test ranges and the total content of them was 11.18%.

  9. 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

  10. Robust optimization of the billet for isothermal local loading transitional region of a Ti-alloy rib-web component based on dual-response surface method

    Science.gov (United States)

    Wei, Ke; Fan, Xiaoguang; Zhan, Mei; Meng, Miao

    2018-03-01

    Billet optimization can greatly improve the forming quality of the transitional region in the isothermal local loading forming (ILLF) of large-scale Ti-alloy ribweb components. However, the final quality of the transitional region may be deteriorated by uncontrollable factors, such as the manufacturing tolerance of the preforming billet, fluctuation of the stroke length, and friction factor. Thus, a dual-response surface method (RSM)-based robust optimization of the billet was proposed to address the uncontrollable factors in transitional region of the ILLF. Given that the die underfilling and folding defect are two key factors that influence the forming quality of the transitional region, minimizing the mean and standard deviation of the die underfilling rate and avoiding folding defect were defined as the objective function and constraint condition in robust optimization. Then, the cross array design was constructed, a dual-RSM model was established for the mean and standard deviation of the die underfilling rate by considering the size parameters of the billet and uncontrollable factors. Subsequently, an optimum solution was derived to achieve the robust optimization of the billet. A case study on robust optimization was conducted. Good results were attained for improving the die filling and avoiding folding defect, suggesting that the robust optimization of the billet in the transitional region of the ILLF was efficient and reliable.

  11. Unequal-thickness billet optimization in transitional region during isothermal local loading forming of Ti-alloy rib-web component using response surface method

    Directory of Open Access Journals (Sweden)

    Ke WEI

    2018-04-01

    Full Text Available Avoiding the folding defect and improving the die filling capability in the transitional region are desired in isothermal local loading forming of a large-scale Ti-alloy rib-web component (LTRC. To achieve a high-precision LTRC, the folding evolution and die filling process in the transitional region were investigated by 3D finite element simulation and experiment using an equal-thickness billet (ETB. It is found that the initial volume distribution in the second-loading region can greatly affect the amount of material transferred into the first-loading region during the second-loading step, and thus lead to the folding defect. Besides, an improper initial volume distribution results in non-concurrent die filling in the cavities of ribs after the second-loading step, and then causes die underfilling. To this end, an unequal-thickness billet (UTB was employed with the initial volume distribution optimized by the response surface method (RSM. For a certain eigenstructure, the critical value of the percentage of transferred material determined by the ETB was taken as a constraint condition for avoiding the folding defect in the UTB optimization process, and the die underfilling rate was considered as the optimization objective. Then, based on the RSM models of the percentage of transferred material and the die underfilling rate, non-folding parameter combinations and optimum die filling were achieved. Lastly, an optimized UTB was obtained and verified by the simulation and experiment. Keywords: Die filling, Folding defect, Isothermal local loading forming, Transitional region, Unequal-thickness billet optimization

  12. 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....

  13. 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...

  14. Chemotaxis and adherence to fungal surfaces are key components of the behavioral response of Burkholderia terrae BS001 to two selected soil fungi.

    Science.gov (United States)

    Haq, Irshad Ul; Calixto, Renata Oliveira da Rocha; Yang, Pu; Dos Santos, Giulia Maria Pires; Barreto-Bergter, Eliana; van Elsas, Jan Dirk

    2016-11-01

    Burkholderia terrae BS001 has previously been proposed to be a 'generalist' associate of soil fungi, but its strategies of interaction have been largely ignored. Here, we studied the chemotactic behavior of B. terrae BS001 towards Lyophyllum sp. strain Karsten and Trichoderma asperellum 302 and the role of fungal surface molecules in their physical interaction with the bacteria. To assess the involvement of the type 3 secretion system (T3SS), wild-type strain BS001 and T3SS mutant strain BS001-ΔsctD were used in the experiments. First, the two fungi showed divergent behavior when confronted with B. terrae BS001 on soil extract agar medium. Lyophyllum sp. strain Karsten revealed slow growth towards the bacterium, whereas T. asperellum 302 grew avidly over it. Both on soil extract and M9 agar, B. terrae BS001 and BS001-ΔsctD moved chemotactically towards the hyphae of both fungi, with a stronger response to Lyophyllum sp. strain Karsten than to T. asperellum 302. The presence of a progressively increasing glycerol level in the M9 agar enhanced the level of movement. Different oxalic acid concentrations exerted varied effects, with a significantly raised chemotactic response at lower, and a subdued response at higher concentrations. Testing of the adherence of B. terrae BS001 and BS001-ΔsctD to Lyophyllum sp. strain Karsten and to cell envelope-extracted ceramide monohexosides (CMHs) revealed that CMHs in both conidia and hyphae could bind strain BS001 cells. As BS001-ΔsctD adhered significantly less to the CMHs than BS001, the T3SS was presumed to have a role in the interaction. In contrast, such avid adherence was not detected with T. asperellum 302. Thus, B. terrae BS001 shows a behavior characterized by swimming towards Lyophyllum sp. strain Karsten and T. asperellum 302 and attachment to the CMH moiety in the cell envelope, in particular of the former. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Emotional responses as independent components in EEG

    DEFF Research Database (Denmark)

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

    2014-01-01

    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...... 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...... by emotional content. We propose that similar approaches to spatial filtering might allow us to retrieve more robust signals in real life mobile usage scenarios, and potentially facilitate design of cognitive interfaces that adapt the selection of media to our emotional responses....

  16. Surface modification method for reactor incore structural component

    International Nuclear Information System (INIS)

    Obata, Minoru; Sudo, Akira.

    1996-01-01

    A large number of metal or ceramic small spheres accelerated by pressurized air are collided against a surface of a reactor incore structures or a welded surface of the structural components, and then finishing is applied by polishing to form compression stresses on the surface. This can change residual stresses into compressive stress without increasing the strength of the surface. Accordingly, stress corrosion crackings of the incore structural components or welded portions thereof can be prevented thereby enabling to extend the working life of equipments. (T.M.)

  17. The inositol-1,2-cyclic phosphate moiety of the cross-reacting determinant, carbohydrate chains, and proteinaceous components are all responsible for the cross-reactivity of trypanosome variant surface glycoproteins.

    Science.gov (United States)

    Escalona, José L; Uzcanga, Graciela L; Carrasquel, Liomary M; Bubis, José

    2018-01-24

    Salivarian trypanosomes evade the host immune system by continually swapping their protective variant surface glycoprotein (VSG) coat. Given that VSGs from various trypanosome stocks exhibited cross-reactivity (Camargo et al., Vet. Parasitol. 207, 17-33, 2015), we analyzed here which components are the antigenic determinants for this cross-reaction. Soluble forms of VSGs were purified from four Venezuelan animal trypanosome isolates: TeAp-N/D1, TeAp-ElFrio01, TeAp-Mantecal01, and TeGu-Terecay323. By using the VSG soluble form from TeAp-N/D1, we found that neither the inositol-1,2-cyclic phosphate moiety of the cross-reacting determinant nor the carbohydrate chains were exclusively responsible for its cross-reactivity. Then, all four purified glycoproteins were digested with papain and the resulting peptides were separated by high-performance liquid chromatography. Dot blot evaluation of the fractions using sera from trypanosome-infected animals yielded peptides that possessed cross-reaction activity, demonstrating for the first time that proteinaceous epitopes are also responsible for the cross-reactivity of trypanosome VSGs.

  18. 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...

  19. 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...

  20. 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...

  1. Adherence of extracellular matrix components to modified surfaces of titanium alloys

    International Nuclear Information System (INIS)

    Stelzer, C; Uhlmann, E; Meinke, M; Lademann, J; Hansen, U

    2009-01-01

    The adherence of biological materials on metal surfaces is of special importance in biology and medicine. The underlying interactions between surface and biological materials (e.g. extracellular matrix components or cells) are responsible for the application as a medical device. Numerous products are made of pure titanium and titanium alloys. This paper shows the influence of a laser production technology on machined surfaces of TiAl 6 V 4 and the resulting adherence of biological material on the basis of the surface characterisation. In this study, different machined TiAl 6 V 4 surfaces were used for coatings with extracellular matrix components. For this process, different coating with collagen I monomers and a complex mixture of extracellular matrix proteins derived from the dermal-epidermal basement membrane zone were analysed. The efficiency of the coating was analysed by different methods and the results are presented in this paper

  2. 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

  3. 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

  4. 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.

  5. 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

  6. 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)

  7. Development of Biomimetic and Functionally Responsive Surfaces

    Science.gov (United States)

    Anastasiadis, Spiros H.

    2010-03-01

    Controlling the surface morphology of solids and manufacturing of functional surfaces with special responsive properties has been the subject of intense research. We report a methodology for creating multifunctionally responsive surfaces by irradiating silicon wafers with femtosecond laser pulses and subsequently coating them with different types of functional conformal coatings. Such surfaces exhibit controlled dual-scale roughness at the micro- and the nano-scale, which mimics the hierarchical morphology of water repellent natural surfaces. When a simple alkylsilane coating is utilized, highly water repellent surfaces are produced that quantitatively compare to those of the Lotus leaf. When a polymer brush is ``grafted from" these surfaces based on a pH-sensitive polymer, the surfaces can alter their behavior from super-hydrophilic (after immersion in a low pH buffer) to super-hydrophobic and water-repellent (following immersion to a high pH buffer). We quantify the water repellency of such responsive systems by drop elasticity measurements whereas we demonstrate that the water repellent state of such surface requires appropriate hydrophobicity of the functionalizing polymer. When a photo-responsive azobenzene-type polymer is deposited, a dynamic optical control of the wetting properties is obtained and the surface can be switched from super-hydrophilic (following UV irradiation) to hydrophobic (following green irradiation). In all the above cases we show that the principal effect of roughness is to cause amplification of the response to the different external stimuli.

  8. 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

  9. 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)

  10. 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)

  11. 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...

  12. 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

  13. Dynamic bioactive stimuli-responsive polymeric surfaces

    Science.gov (United States)

    Pearson, Heather Marie

    This dissertation focuses on the design, synthesis, and development of antimicrobial and anticoagulant surfaces of polyethylene (PE), polypropylene (PP), and poly(tetrafluoroethylene) (PTFE) polymers. Aliphatic polymeric surfaces of PE and PP polymers functionalized using click chemistry reactions by the attachment of --COOH groups via microwave plasma reactions followed by functionalization with alkyne moieties. Azide containing ampicillin (AMP) was synthesized and subsequently clicked into the alkyne prepared PE and PP surfaces. Compared to non-functionalized PP and PE surfaces, the AMP clicked surfaces exhibited substantially enhanced antimicrobial activity against Staphylococcus aureus bacteria. To expand the biocompatibility of polymeric surface anticoagulant attributes, PE and PTFE surfaces were functionalized with pH-responsive poly(2-vinyl pyridine) (P2VP) and poly(acrylic acid) (PAA) polyelectrolyte tethers terminated with NH2 and COOH groups. The goal of these studies was to develop switchable stimuli-responsive polymeric surfaces that interact with biological environments and display simultaneous antimicrobial and anticoagulant properties. Antimicrobial AMP was covalently attached to --COOH terminal ends of protected PAA, while anticoagulant heparin (HEP) was attached to terminal --NH2 groups of P2VP. When pH 5.5, they collapse while the PAA segments extend. Such surfaces, when exposed to Staphylococcus aureus, inhibit bacterial growth due to the presence of AMP, as well as are effective anticoagulants due to the presence of covalently attached HEP. Comparison of these "dynamic" pH responsive surfaces with "static" surfaces terminated with AMP entities show significant enhancement of longevity and surface activity against microbial film formation. The last portion of this dissertation focuses on the covalent attachment of living T1 and Φ11 bacteriophages (phages) on PE and PTFE surface. This was accomplished by carbodiimide coupling between --COOH

  14. 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.

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

    KAUST Repository

    Yuehong, Xu; Yanfeng, Li; Chunxiu, Tian; Jiaguang, Han; Quan, Xu; Xueqian, Zhang; Xixiang, Zhang; Ying, Zhang; Weili, Zhang

    2018-01-01

    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. Response Surface Methodology: 1966-1986

    Science.gov (United States)

    1986-09-01

    male broilers to examine quantitatively the protein levels in starter and Gnisher rations and the time of ration change to optimize body weight, carcass...1983). ’Akn Investigation of Protein Levels for Broiler Starter and Finisher Rations and the Time of Ration Change by Response Surface Methodology...when Responses Within a Litter are Correlated,’ Biometrics, 37, 153-156. Shek, E., Ghani, M. and Jones, R.E. (1980). "Simplex Search in Optimization

  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. Pavement Aging Model by Response Surface Modeling

    Directory of Open Access Journals (Sweden)

    Manzano-Ramírez A.

    2011-10-01

    Full Text Available In this work, surface course aging was modeled by Response Surface Methodology (RSM. The Marshall specimens were placed in a conventional oven for time and temperature conditions established on the basis of the environment factors of the region where the surface course is constructed by AC-20 from the Ing. Antonio M. Amor refinery. Volatilized material (VM, load resistance increment (ΔL and flow resistance increment (ΔF models were developed by the RSM. Cylindrical specimens with real aging were extracted from the surface course pilot to evaluate the error of the models. The VM model was adequate, in contrast (ΔL and (ΔF models were almost adequate with an error of 20 %, that was associated with the other environmental factors, which were not considered at the beginning of the research.

  19. Surface erosion of fusion reactor components due to radiation blistering and neutron sputtering

    International Nuclear Information System (INIS)

    Das, S.K.; Kaminsky, M.

    1975-01-01

    Radiation blistering and neutron sputtering can lead to the surface erosion of fusion reactor components exposed to plasma radiations. Recent studies of methods to reduce the surface erosion caused by these processes are discussed

  20. Identification of Aspergillus fumigatus Surface Components That Mediate Interaction of Conidia and Hyphae With Human Platelets.

    Science.gov (United States)

    Rambach, Günter; Blum, Gerhard; Latgé, Jean-Paul; Fontaine, Thierry; Heinekamp, Thorsten; Hagleitner, Magdalena; Jeckström, Hanna; Weigel, Günter; Würtinger, Philipp; Pfaller, Kristian; Krappmann, Sven; Löffler, Jürgen; Lass-Flörl, Cornelia; Speth, Cornelia

    2015-10-01

    Platelets were recently identified as a part of innate immunity. They are activated by contact with Aspergillus fumigatus; putative consequences include antifungal defense but also thrombosis, excessive inflammation, and thrombocytopenia. We aimed to identify those fungal surface structures that mediate interaction with platelets. Human platelets were incubated with Aspergillus conidia and hyphae, isolated wall components, or fungal surface mutants. Interaction was visualized microscopically; activation was quantified by flow cytometry of specific markers. The capacity of A. fumigatus conidia to activate platelets is at least partly due to melanin, because this effect can be mimicked with "melanin ghosts"; a mutant lacking melanin showed reduced platelet stimulating potency. In contrast, conidial hydrophobin masks relevant structures, because an A. fumigatus mutant lacking the hydrophobin protein induced stronger platelet activation than wild-type conidia. A. fumigatus hyphae also contain surface structures that interact with platelets. Wall proteins, galactomannan, chitin, and β-glucan are not the relevant hyphal components; instead, the recently identified fungal polysaccharide galactosaminogalactan potently triggered platelet activation. Conidial melanin and hydrophobin as well as hyphal galactosaminogalactan represent important pathogenicity factors that modulate platelet activity and thus might influence immune responses, inflammation, and thrombosis in infected patients. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  1. Reliability of surface inspection techniques for pressurized components

    International Nuclear Information System (INIS)

    Kauppinen, P.; Sillanpaeae, J.

    1991-01-01

    In the Nordtest NDT-programme (1984 - 1988) the detection of flaws by surface inspection methods has been studied. In the round-robin exercise, 133 test pieces have been inspected by 32 inspectors in Denmark, Finland, Norway and Sweden. From the results, the detectability of defects by magnetic particle and liquid-penetrant testing and the influence of materials and techniques used are evaluated. (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......), and a bend loss of ~5 dB for a bend radius of 15 mm are evaluated for 15-nm-thick and 8-mm-wide stripes at the wavelength of 1550 nm. LR-SPP-based 3-dB power Y-splitters, multimode interference waveguides, and directional couplers are demonstrated and investigated. At 1570 nm, coupling lengths of 1.9 and 0...

  3. Simulating the Impact Response of Composite Airframe Components

    Science.gov (United States)

    Jackson, Karen E.; Littell, Justin D.; Fasanella, Edwin L.

    2014-01-01

    In 2010, NASA Langley Research Center obtained residual hardware from the US Army's Survivable Affordable Repairable Airframe Program (SARAP). The hardware consisted of a composite fuselage section that was representative of the center section of a Black Hawk helicopter. The section was fabricated by Sikorsky Aircraft Corporation and designated the Test Validation Article (TVA). The TVA was subjected to a vertical drop test in 2008 to evaluate a tilting roof concept to limit the intrusion of overhead mass items, such as the rotor transmission, into the fuselage cabin. As a result of the 2008 test, damage to the hardware was limited primarily to the roof. Consequently, when the post-test article was obtained in 2010, the roof area was removed and the remaining structure was cut into six different types of test specimens including: (1) tension and compression coupons for material property characterization, (2) I-beam sections, (3) T-sections, (4) cruciform sections, (5) a large subfloor section, and (6) a forward framed fuselage section. In 2011, NASA and Sikorsky entered into a cooperative research agreement to study the impact responses of composite airframe structures and to evaluate the capabilities of the explicit transient dynamic finite element code, LS-DYNA®, to simulate these responses including damage initiation and progressive failure. Finite element models of the composite specimens were developed and impact simulations were performed. The properties of the composite material were represented using both a progressive in-plane damage model (Mat 54) and a continuum damage mechanics model (Mat 58) in LS-DYNA. This paper provides test-analysis comparisons of time history responses and the location and type of damage for representative I-beam, T-section, and cruciform section components.

  4. 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...

  5. Vertical components of surface vibrations induced by mining tremors in the Upper Silesian Coalfield, Poland

    International Nuclear Information System (INIS)

    Maciag, E.; Kowalski, W.

    1997-01-01

    Characteristics of vertical components of surface vibration is epicentral zones due to mining tremors in the Upper Silesian Coalfield (USC) are analysed. Both maximum acceleration amplitudes and dominant frequencies of vertical (Z) and horizontal (N-S and E-W) components of vibrations are compared. The role played by the vertical components of vibrations in estimates of hazard for surface structures excited by mining tremors is discussed. 8 refs., 7 figs

  6. Response spectrum analysis of coupled structural response to a three component seismic disturbance

    International Nuclear Information System (INIS)

    Boulet, J.A.M.; Carley, T.G.

    1977-01-01

    The work discussed herein is a comparison and evaluation of several response spectrum analysis (RSA) techniques as applied to the same structural model with seismic excitation having three spatial components. Lagrange's equations of motion for the system were written in matrix form and uncoupled with the modal matrix. Numerical integration (fourth order Runge-Kutta) of the resulting model equations produced time histories of system displacements in response to simultaneous application of three orthogonal components of ground motion, and displacement response spectra for each modal coordinate in response to each of the three ground motion components. Five different RSA techniques were used to combine the spectral displacements and the modal matrix to give approximations of maximum system displacements. These approximations were then compared with the maximum system displacements taken from the time histories. The RSA techniques used are the method of absolute sums, the square root of the sum of the squares, the double sum approach, the method of closely spaced modes, and Lin's method. The vectors of maximum system displacements as computed by the time history analysis and the five response spectrum analysis methods are presented. (Auth.)

  7. 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.

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

    African Journals Online (AJOL)

    Application of Response Surface Methodology for Optimizing Oil Extraction Yield From ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search ... from tropical almond seed by the use of response surface methodology (RSM).

  9. Response spectrum analysis of coupled structural response to a three component seismic disturbance

    International Nuclear Information System (INIS)

    Boulet, J.A.M.; Carley, T.G.

    1977-01-01

    The work discussed herein is a comparison and evaluation of several response spectrum analysis (RSA) techniques as applied to the same structural model with seismic excitation having three spatial components. The structural model includes five lumped masses (floors) connected by four elastic members. The base is supported by three translational springs and two horizontal torsional springs. In general, the mass center and shear center of a building floor are distinct locations. Hence, inertia forces, which act at the mass center, induce twisting in the structure. Through this induced torsion, the lateral (x and y) displacements of the mass elements are coupled. The ground motion components used for this study are artificial earthquake records generated from recorded accelerograms by a spectrum modification technique. The accelerograms have response spectra which are compatible with U.S. NRC Regulatory Guide 1.60. Lagrange's equations of motion for the system were written in matrix form and uncoupled with the modal matrix. Numerical integration (fourth order Runge-Kutta) of the resulting modal equations produced time histories of system displacements in response to simultaneous application of three orthogonal components of ground motion, and displacement response spectra for each modal coordinate in response to each of the three ground motion components. Five different RSA techniques were used to combine the spectral displacements and the modal matrix to give approximations of maximum system displacements. These approximations were then compared with the maximum system displacements taken from the time histories. The RSA techniques used are the method of absolute sums, the square root of the sum of the sum of the squares, the double sum approach, the method of closely spaced modes, and Lin's method

  10. 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.

  11. Nuclear electronic components of surface contamination monitor based on multi-electrode proportional counter

    International Nuclear Information System (INIS)

    Du Xiangyang; Zhang Yong; Han Shuping; Rao Xianming; Fang Jintu

    2001-01-01

    The nuclear electronic components applying in Portal Monitor and Hands and Feet Surface Contamination Monitor were based on modern integrated circuit are introduced. The detailed points in circuit design and manufacturing technique are analyzed

  12. 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....

  13. Different types of configurations of equipotential surfaces of binary systems with very luminous components

    Energy Technology Data Exchange (ETDEWEB)

    Zorec, J [Centre National de la Recherche Scientifique, 75 - Paris (France). Inst. d' Astrophysique; Niemela, V [Instituto de Astronomia y Fisica del Espacio, Buenos Aires (Argentina)

    1980-02-04

    If the luminosities and the masses of the components of a binary system are known, it is possible to determine from the diagrams presented here, the type of configuration of equipotential surfaces that correspond to it.

  14. Different types of configurations of equipotential surfaces of binary systems with very luminous components

    International Nuclear Information System (INIS)

    Zorec, Juan

    1980-01-01

    If the luminosities and the masses of the components of a binary system are known, it is possible to determine from the diagrams presented here, the type of configuration of equipotential surfaces that correspond to it [fr

  15. 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...

  16. 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...

  17. OSCAR2000 : a multi-component 3-dimensional oil spill contingency and response model

    International Nuclear Information System (INIS)

    Reed, M.; Daling, P.S.; Brakstad, O.G.; Singsaas, I.; Faksness, L.-G.; Hetland, B.; Ekrol, N.

    2000-01-01

    Researchers at SINTEF in Norway have studied the weathering of surface oil. They developed a realistic model to analyze alternative spill response strategies. The model represented the formation and composition of the water-accommodated fraction (WAF) of oil for both treated and untreated oil spills. As many as 25 components, pseudo-components, or metabolites were allowed for the specification of oil. Calculations effected using OSCAR were verified in great detail on numerous occasions. The model made it possible to determine rather realistically the dissolution, transformation, and toxicology of dispersed oil clouds, as well as evaporation, emulsification, and natural dispersion. OSCAR comprised a data-based oil weathering model, a three-dimensional oil trajectory and chemical fates model, an oil spill combat model, exposure models for birds, marine mammals, fish and ichthyoplankton. 17 refs., 1 tab., 11 figs

  18. 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

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

    DEFF Research Database (Denmark)

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

    scanning probe image processor (SPIP) software and the results of the surface roughness parameters obtained were subjected to statistical analyses. The bearing area ratio was introduced and applied to the surface roughness analysis. From the results, the surface quality of the standard comparators...... is successfully characterised and it was established that the areal parameters are more informative for sand cast components. The roughness values of the standard visual comparators can serve as a control for the cast components and for order specifications in the foundry industry. A series of iron castings were...... 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...

  20. Detailed analysis of surface asperity deformation mechanism in diffusion bonding of steel hollow structural components

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, C. [School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072 (China); Laboratoire de Mecanique des Contacts et des Structures (LaMCoS), INSA Lyon, 20 Avenue des Sciences, F-69621 Villeurbanne Cedex (France); Li, H. [School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072 (China); Li, M.Q., E-mail: zc9997242256@126.com [School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072 (China)

    2016-05-15

    Graphical abstract: This study focused on the detailed analysis of surface asperity deformation mechanism in diffusion bonding of steel hollow structural component. A special surface with regular patterns was processed to be joined so as to observe the extent of surface asperity deformation under different applied bonding pressures. Fracture surface characteristic combined with surface roughness profiles distinctly revealed the enhanced surface asperity deformation as the applied pressure increases. The influence of surface asperity deformation mechanism on joint formation was analyzed: (a) surface asperity deformation not only directly expanded the interfacial contact areas, but also released deformation heat and caused defects, indirectly accelerating atomic diffusion, then benefits to void shrinkage; (b) surface asperity deformation readily introduced stored energy difference between two opposite sides of interface grain boundary, resulting in strain induced interface grain boundary migration. In addition, the influence of void on interface grain boundary migration was analyzed in detail. - Highlights: • A high quality hollow structural component has been fabricated by diffusion bonding. • Surface asperity deformation not only expands the interfacial contact areas, but also causes deformation heat and defects to improve the atomic diffusion. • Surface asperity deformation introduces the stored energy difference between the two opposite sides of interface grain boundary, leading to strain induced interface grain boundary migration. • The void exerts a dragging force on the interface grain boundary to retard or stop interface grain boundary migration. - Abstract: This study focused on the detailed analysis of surface asperity deformation mechanism in similar diffusion bonding as well as on the fabrication of high quality martensitic stainless steel hollow structural components. A special surface with regular patterns was processed to be joined so as to

  1. Dependence of partial molecules surface area on the third component in lyotropic liquid crystals

    International Nuclear Information System (INIS)

    Badalyan, H.G.; Ghazaryan, Kh.M.; Yayloyan, S.M.

    2015-01-01

    Free surface of one amphiphilic molecule head of a lyotropic liquid crystal has been investigated by X-Ray diffraction method, at small and large angles, in the presence of the third component. The pentadecilsulphonat-water system in the presence of cholesterol as well as the lecithin-water system in the presence of decanol were investigated. It is shown that the above mentioned free surface decreases if the cholesterol concentration increases, while this surface increases in the case of water concentration increase. However, it increases slower than in the case of the two-component system. The same is observed for the lecithin-water-decanol system

  2. 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 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...

  3. Response Surface Optimized Extraction of Total Triterpene Acids ...

    African Journals Online (AJOL)

    Tropical Journal of Pharmaceutical Research May 2014; 13 (5): 787-792 ... surface method were used to optimize the extraction process, while antioxidant activity was evaluated in vitro using α ... Response surface methodology is increasingly.

  4. Blind Separation of Event-Related Brain Responses into Independent Components

    National Research Council Canada - National Science Library

    Makeig, Scott

    1996-01-01

    .... We report here a method for the blind separation of event-related brain responses into spatially stationary and temporally independent subcomponents using an Independent Component Analysis algorithm...

  5. 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.

  6. 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.

  7. Response of Yield and Yield Components of Tef [Eragrostis Tef ...

    African Journals Online (AJOL)

    The partial budget analysis also indicates that applications of 46 kg. N ha-1 and 10 kg P ha-1 are ..... (1994) indicated that where the grain yield response is negative, yield reduction is primarily caused by a .... An Economic Training. Manual.

  8. 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

  9. 2012 Survey of Reserve Components Spouses (RCSS): Tabulations of Responses

    Science.gov (United States)

    2012-09-30

    injury/medical problems Child care problems Other family/personal obligation Maternity / paternity leave Labor dispute Weather affected job School...Did you interact with the unit or Service point of contact? ............................. 262  36.  How satisfied are you with the level of assistance...I did not interact with the unit or Service point of contact were tabulated separately, as responses to the constructed question Did you interact

  10. 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

  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.

    1997-12-31

    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. [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.

  13. 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)....

  14. 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...

  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. Response surface reconciliation method of bolted joints structure

    Directory of Open Access Journals (Sweden)

    Yunus Mohd Azmi

    2017-01-01

    Full Text Available Structural joining methods such as bolted joints are commonly used for the assembly of structural components due to their simplicity and easy maintenance. Understandably, the dynamic characteristic of bolted joined structure is mainly influenced by the properties of their joints such as preload on the bolts and joints stiffness which alter the measured dynamics response of the structure. Therefore, the need to include the local effect of the bolted joints into the numerical model of the bolted joined structure is vitally important in order to represent the model accurately. In this paper, a few types of connector elements that can be used to represent the bolted joints such as CBAR, CBEAM and CELAS have been investigated numerically and experimentally. The initial numerical results of these element connectors are compared with the experimental results in term of natural frequencies and mode shapes. The comparative evaluation of numerical and the experimental data are performed in order to provide some insights of inaccuracies in the numerical model due to invalid assumption in the numerical modelling such as geometry, material properties, and boundary conditions. The discrepancies between both results (numerical and experimental data are then corrected using the response surface reconciliation method (RSRM through which the finite element model is altered in order to provide closer agreement with the measured data so that it can be used for subsequence analysis.

  17. 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

  18. 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.

  19. 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

  20. 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.

  1. A Novel Method for Surface Defect Detection of Photovoltaic Module Based on Independent Component Analysis

    Directory of Open Access Journals (Sweden)

    Xuewu Zhang

    2013-01-01

    Full Text Available This paper proposed a new method for surface defect detection of photovoltaic module based on independent component analysis (ICA reconstruction algorithm. Firstly, a faultless image is used as the training image. The demixing matrix and corresponding ICs are obtained by applying the ICA in the training image. Then we reorder the ICs according to the range values and reform the de-mixing matrix. Then the reformed de-mixing matrix is used to reconstruct the defect image. The resulting image can remove the background structures and enhance the local anomalies. Experimental results have shown that the proposed method can effectively detect the presence of defects in periodically patterned surfaces.

  2. 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.

  3. Frequency response in surface-potential driven electrohydrodynamics

    DEFF Research Database (Denmark)

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

    2006-01-01

    Using a Fourier approach we offer a general solution to calculations of slip velocity within the circuit description of the electrohydrodynamics in a binary electrolyte confined by a plane surface with a modulated surface potential. We consider the case with a spatially constant intrinsic surface...... 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...

  4. Accelerator system for producing two-component beams for studies of interactive surface effects

    International Nuclear Information System (INIS)

    Kaminsky, M.; Das, S.K.; Ekern, R.; Hess, D.C.

    1977-01-01

    For studies of interactive surface effects caused by the simultaneous bombardment of targets by both chemically active and inactive ion species (e.g., D + and He + , respectively) a two beam component accelerator facility was placed in operation. One component, consisting of light ions (e.g., H, D, He) is accelerated by a 2-MV Van de Graaff accelerator which provides a mass analyzed and focussed beam for the energy range from approximately 100-keV to 2-MeV (for singly charged ions). The other component is a beam of light ions in the energy range from approximately 10-keV to 100-keV. This is furnished by a 100-kV dc accelerator system which provides a mass analyzed focussed beam. This beam is guided into the beam line of the Van de Graaff accelerator electrostatically, and with the aid of beam steerers it is made to be co-axial with the Van de Graaff generated beam. The angle of incidence becomes hereby a free parameter for the interaction of the mixed beams with a surface. For each beam component, current densities of 650 μA cm -2 on target can readily be obtained. In order to reduce carbon contamination of the irradiated targets significantly, stainless steel beam lines have been used together with a combination of turbomolecular pumps and ion-sublimation pumps.A total pressure of 2 to 3 x 10 -8 torr in the beam lines and of 2 x 10 -9 torr in the target chamber can be obtained readily. Experimental results on the surface damage of Ni bombarded simultaneously with He + and D + ions are presented. The importance of such studies of interactive surface effects for the controlled thermonuclear fusion program are discussed

  5. 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

  6. 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...

  7. Statistical optimization of cultural conditions by response surface ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-08-04

    Aug 4, 2009 ... Full Length Research Paper. Statistical optimization of cultural conditions by response surface methodology for phenol degradation by a novel ... Phenol is a hydrocarbon compound that is highly toxic, ... Microorganism.

  8. Sediment studies at Bikini Atoll part 1. distribution of fine and coarse components in surface sediments

    International Nuclear Information System (INIS)

    Noshkin, V. E.; Eagle, R.J.; Robison, W.L.

    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 over the floor of Bikini lagoon. 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 what modifications occurred since the sediment composition was first described in samples collected before testing in 1946. In this report a comparison is made of the amount and distribution of fine material associated with the lagoon surface sediment before and after the testing of nuclear devices. Nuclear testing produced more finely divided material in-the surface sediment layer over large areas of the lagoon and especially in regions of the lagoon and reef adjacent to test sites. Five cratering events at Bikini Atoll generated sufficient material to account for the inventory of new fine material found over the bottom surface 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 alter the geographical features of the major sedimentary components over most of the lagoon floor

  9. 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

  10. Sediment studies at Bikini Atoll part 1. distribution of fine and coarse components in surface sediments

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V. E.; Eagle, R.J.; Robison, W.L.

    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 over the floor of Bikini lagoon. 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 what modifications occurred since the sediment composition was first described in samples collected before testing in 1946. In this report a comparison is made of the amount and distribution of fine material associated with the lagoon surface sediment before and after the testing of nuclear devices. Nuclear testing produced more finely divided material in-the surface sediment layer over large areas of the lagoon and especially in regions of the lagoon and reef adjacent to test sites. Five cratering events at Bikini Atoll generated sufficient material to account for the inventory of new fine material found over the bottom surface 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 alter the geographical features of the major sedimentary components over most of the lagoon floor.

  11. Near-surface thermal characterization of plasma facing components using the 3-omega method

    International Nuclear Information System (INIS)

    Dechaumphai, Edward; Barton, Joseph L.; Tesmer, Joseph R.; Moon, Jaeyun; Wang, Yongqiang; Tynan, George R.; Doerner, Russell P.; Chen, Renkun

    2014-01-01

    Near-surface regime plays an important role in thermal management of plasma facing components in fusion reactors. Here, we applied a technique referred to as the ‘3ω’ method to measure the thermal conductivity of near-surface regimes damaged by ion irradiation. By modulating the frequency of the heating current in a micro-fabricated heater strip, the technique enables the probing of near-surface thermal properties. The technique was applied to measure the thermal conductivity of a thin ion-irradiated layer on a tungsten substrate, which was found to decrease by nearly 60% relative to pristine tungsten for a Cu ion dosage of 0.2 dpa

  12. 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

  13. The effect of cell surface components on adhesion ability of Lactobacillus rhamnosus.

    Science.gov (United States)

    Polak-Berecka, Magdalena; Waśko, Adam; Paduch, Roman; Skrzypek, Tomasz; Sroka-Bartnicka, Anna

    2014-10-01

    The aim of this study was to analyze the cell envelope components and surface properties of two phenotypes of Lactobacillus rhamnosus isolated from the human gastrointestinal tract. The ability of the bacteria to adhere to human intestinal cells and to aggregate with other bacteria was determined. L. rhamnosus strains E/N and PEN differed with regard to the presence of exopolysaccharides (EPS) and specific surface proteins. Transmission electron microscopy showed differences in the structure of the outer cell surface of the strains tested. Bacterial surface properties were analyzed by Fourier transform infrared spectroscopy, fatty acid methyl esters and hydrophobicity assays. Aggregation capacity and adhesion of the tested strains to the human colon adenocarcinoma cell line HT29 was determined. The results indicated a high adhesion and aggregation ability of L. rhamnosus PEN, which possessed specific surface proteins, had a unique fatty acid content, and did not synthesize EPS. Adherence of L. rhamnosus was dependent on specific interactions and was promoted by surface proteins (42-114 kDa) and specific fatty acids. Polysaccharides likely hindered bacterial adhesion and aggregation by masking protein receptors. This study provides information on the cell envelope constituents of lactobacilli that influence bacterial aggregation and adhesion to intestinal cells. This knowledge will help to understand better their specific contribution in commensal-host interactions and adaptation to this ecological niche.

  14. Osteoblastic response to pectin nanocoating on titanium surfaces

    DEFF Research Database (Denmark)

    Gurzawska, Katarzyna; Svava, Rikke; Yihua, Yu

    2014-01-01

    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...

  15. Optimization of composite flour biscuits by mixture response surface methodology.

    Science.gov (United States)

    Okpala, Laura C; Okoli, Eric C

    2013-08-01

    Biscuits were produced from blends of pigeon pea, sorghum and cocoyam flours. The study was carried out using mixture response surface methodology as the optimization technique. Using the simplex centroid design, 10 formulations were obtained. Protein and sensory quality of the biscuits were analyzed. The sensory attributes studied were appearance, taste, texture, crispness and general acceptability, while the protein quality indices were biological value and net protein utilization. The results showed that while the addition of pigeon pea improved the protein quality, its addition resulted in reduced sensory ratings for all the sensory attributes with the exception of appearance. Some of the biscuits had sensory ratings, which were not significantly different (p > 0.05) from biscuits made with wheat. Rat feeding experiments indicated that the biological value and net protein utilization values obtained for most of the biscuits were above minimum recommended values. Optimization suggested biscuits containing 75.30% sorghum, 0% pigeon pea and 24.70% cocoyam flours as the best proportion of these components. This sample received good scores for the sensory attributes.

  16. 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)

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

    Science.gov (United States)

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

    2014-03-07

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Henrik A; Manuilskiy, Anatoliy; Haller, Stefan; Sidén, Johan; Nilsson, Hans-Erik [Department of Electronics Design, Mid Sweden University, SE-851 70 Sundsvall (Sweden); Hummelgård, Magnus; Olin, Håkan [Department of Natural Science, Mid Sweden University, SE-851 70 Sundsvall (Sweden); Hummelgård, Christine [Acreo Swedish ICT AB, Håstaholmen 4, SE-824 42 Hudiksvall (Sweden)

    2014-03-07

    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)

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. Surface conditioning with Escherichia coli cell wall components can reduce biofilm formation by decreasing initial adhesion

    Directory of Open Access Journals (Sweden)

    Luciana C. Gomes

    2017-07-01

    Full Text Available Bacterial adhesion and biofilm formation on food processing surfaces pose major risks to human health. Non-efficient cleaning of equipment surfaces and piping can act as a conditioning layer that affects the development of a new biofilm post-disinfection. We have previously shown that surface conditioning with cell extracts could reduce biofilm formation. In the present work, we hypothesized that E. coli cell wall components could be implicated in this phenomena and therefore mannose, myristic acid and palmitic acid were tested as conditioning agents. To evaluate the effect of surface conditioning and flow topology on biofilm formation, assays were performed in agitated 96-well microtiter plates and in a parallel plate flow chamber (PPFC, both operated at the same average wall shear stress (0.07 Pa as determined by computational fluid dynamics (CFD. It was observed that when the 96-well microtiter plate and the PPFC were used to form biofilms at the same shear stress, similar results were obtained. This shows that the referred hydrodynamic feature may be a good scale-up parameter from high-throughput platforms to larger scale flow cell systems as the PPFC used in this study. Mannose did not have any effect on E. coli biofilm formation, but myristic and palmitic acid inhibited biofilm development by decreasing cell adhesion (in about 50%. These results support the idea that in food processing equipment where biofilm formation is not critical below a certain threshold, bacterial lysis and adsorption of cell components to the surface may reduce biofilm buildup and extend the operational time.

  4. Individual differences in anxiety responses to stressful situations : A three-mode component analysis model

    NARCIS (Netherlands)

    Van Mechelen, Iven; Kiers, Henk A.L.

    1999-01-01

    The three-mode component analysis model is discussed as a tool for a contextualized study of personality. When applied to person x situation x response data, the model includes sets of latent dimensions for persons, situations, and responses as well as a so-called core array, which may be considered

  5. 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

  6. 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.

  7. 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...... 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...... of channels with good performance. Guiding of LR-SPPs along nm-thin and µm-wide gold stripes embedded in polymer is investigated in the wavelength range of 1250 – 1650 nm. LR-SPP guiding properties, such as the propagation loss and mode field diameter, are studied for different stripe widths and thicknesses...

  8. Identification of chemical components of combustion emissions that affect pro-atherosclerotic vascular responses in mice.

    Science.gov (United States)

    Seilkop, Steven K; Campen, Matthew J; Lund, Amie K; McDonald, Jacob D; Mauderly, Joe L

    2012-04-01

    Combustion emissions cause pro-atherosclerotic responses in apolipoprotein E-deficient (ApoE/⁻) mice, but the causal components of these complex mixtures are unresolved. In studies previously reported, ApoE⁻/⁻ mice were exposed by inhalation 6 h/day for 50 consecutive days to multiple dilutions of diesel or gasoline exhaust, wood smoke, or simulated "downwind" coal emissions. In this study, the analysis of the combined four-study database using the Multiple Additive Regression Trees (MART) data mining approach to determine putative causal exposure components regardless of combustion source is reported. Over 700 physical-chemical components were grouped into 45 predictor variables. Response variables measured in aorta included endothelin-1, vascular endothelin growth factor, three matrix metalloproteinases (3, 7, 9), metalloproteinase inhibitor 2, heme-oxygenase-1, and thiobarbituric acid reactive substances. Two or three predictors typically explained most of the variation in response among the experimental groups. Overall, sulfur dioxide, ammonia, nitrogen oxides, and carbon monoxide were most highly predictive of responses, although their rankings differed among the responses. Consistent with the earlier finding that filtration of particles had little effect on responses, particulate components ranked third to seventh in predictive importance for the eight response variables. MART proved useful for identifying putative causal components, although the small number of pollution mixtures (4) can provide only suggestive evidence of causality. The potential independent causal contributions of these gases to the vascular responses, as well as possible interactions among them and other components of complex pollutant mixtures, warrant further evaluation.

  9. 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.

  10. Calculation of parameter failure probability of thermodynamic system by response surface and importance sampling method

    International Nuclear Information System (INIS)

    Shang Yanlong; Cai Qi; Chen Lisheng; Zhang Yangwei

    2012-01-01

    In this paper, the combined method of response surface and importance sampling was applied for calculation of parameter failure probability of the thermodynamic system. The mathematics model was present for the parameter failure of physics process in the thermodynamic system, by which the combination arithmetic model of response surface and importance sampling was established, then the performance degradation model of the components and the simulation process of parameter failure in the physics process of thermodynamic system were also present. The parameter failure probability of the purification water system in nuclear reactor was obtained by the combination method. The results show that the combination method is an effective method for the calculation of the parameter failure probability of the thermodynamic system with high dimensionality and non-linear characteristics, because of the satisfactory precision with less computing time than the direct sampling method and the drawbacks of response surface method. (authors)

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. Application of response surfaces for reliability analysis of marine structures

    International Nuclear Information System (INIS)

    Leira, Bernt J.; Holmas, Tore; Herfjord, Kjell

    2005-01-01

    Marine structures subjected to multiple environmental loads (i.e. waves, current, wind) are considered. These loads are characterized by a set of corresponding parameters. The structural fatigue damage and long-term response are expressed in terms of these environmental parameters based on application of polynomial response surfaces. For both types of analysis, an integration across the range of variation for all the environmental parameters is required. The location of the intervals which give rise to the dominant contribution for these integrals depends on the relative magnitude of the coefficients defining the polynomials. The required degree of numerical subdivision in order to obtain accurate results is also of interest. These issues are studied on a non-dimensional form. The loss of accuracy which results when applying response surfaces of too low order is also investigated. Response surfaces with cut-off limits at specific lower-bound values for the environmental parameters are further investigated. Having obtained general expressions on non-dimensional form, examples which correspond to specific response quantities for marine structures are considered. Typical values for the polynomial coefficients, and for the statistical distributions representing the environmental parameters, are applied. Convergence studies are subsequently performed for the particular example response quantities in order to make comparison with the general formulation. For the extreme response, the application of 'extreme contours' obtained from the statistical distributions of the environmental parameters is explored

  16. Mechanical response of wall-patterned GaAs surface

    International Nuclear Information System (INIS)

    Le Bourhis, E.; Patriarche, G.

    2005-01-01

    Wall-patterned GaAs surfaces have been elaborated by photolithography and dry etching. Different surfaces were produced in order to change the aspect ratio of the walls formed at the substrate surface. The mechanical behaviour of individual walls was investigated by nanoindentation and the responses were compared to that of a standard bulk reference (flat surface). Deviation from the bulk response is detected in a load range of 1-25 mN depending on the aspect ratio of the walls. A central plastic zone criterion is proposed in view of transmission electron microscopy images of indented walls and allows the prediction of the response deviation of a given wall if its width is known. The mechanical response of the different types of walls is further investigated in terms of stiffness, total penetration of indenter and apparent hardness, and is scanned in relation to the proximity of a wall side. Overall results show that contact stiffness remains almost unaffected by aspect ratio, while penetration drastically increases because of the free sides of the wall as compared to a flat surface (bulk substrate). The application of substrate patterning for optoelectronic devices is discussed in the perspective of eliminating residual dislocations appearing in mismatched structures

  17. 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

  18. Will surface winds weaken in response to global warming?

    Science.gov (United States)

    Ma, Jian; Foltz, Gregory R.; Soden, Brian J.; Huang, Gang; He, Jie; Dong, Changming

    2016-12-01

    The surface Walker and tropical tropospheric circulations have been inferred to slow down from historical observations and model projections, yet analysis of large-scale surface wind predictions is lacking. Satellite measurements of surface wind speed indicate strengthening trends averaged over the global and tropical oceans that are supported by precipitation and evaporation changes. Here we use corrected anemometer-based observations to show that the surface wind speed has not decreased in the averaged tropical oceans, despite its reduction in the region of the Walker circulation. Historical simulations and future projections for climate change also suggest a near-zero wind speed trend averaged in space, regardless of the Walker cell change. In the tropics, the sea surface temperature pattern effect acts against the large-scale circulation slow-down. For higher latitudes, the surface winds shift poleward along with the eddy-driven mid-latitude westerlies, resulting in a very small contribution to the global change in surface wind speed. Despite its importance for surface wind speed change, the influence of the SST pattern change on global-mean rainfall is insignificant since it cannot substantially alter the global energy balance. As a result, the precipitation response to global warming remains ‘muted’ relative to atmospheric moisture increase. Our results therefore show consistency between projections and observations of surface winds and precipitation.

  19. 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)

  20. 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.

  1. 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

  2. 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).

  3. 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 ...

  4. 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.

  5. 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

  6. Photo-responsive surface topology in chiral nematic media

    Science.gov (United States)

    Liu, Danqing; Bastiaansen, Cees W. M.; Toonder, Jaap. M. J.; Broer, Dirk J.

    2012-03-01

    We report on the design and fabrication of 'smart surfaces' that exhibit dynamic changes in their surface topology in response to exposure to light. The principle is based on anisotropic geometric changes of a liquid crystal network upon a change of the molecular order parameter. The photomechanical property of the coating is induced by incorporating an azobenzene moiety into the liquid crystal network. The responsive surface topology consists of regions with two different types of molecular order: planar chiral-nematic areas and homeotropic. Under flood exposure with 365 nm light the surfaces deform from flat to one with a surface relief. The height of the relief structures is of the order of 1 um corresponding to strain difference of around 20%. Furthermore, we demonstrate surface reliefs can form either convex or concave structures upon exposure to UV light corresponding to the decrease or increase molecular order parameter, respectively, related to the isomeric state of the azobenzene crosslinker. The reversible deformation to the initial flat state occurs rapidly after removing the light source.

  7. 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.

  8. Theoretical Insight of Physical Adsorption for a Single-Component Adsorbent + Adsorbate System: I. Thermodynamic Property Surfaces

    KAUST Repository

    Chakraborty, Anutosh; Saha, Bidyut Baran; Ng, Kim Choon; Koyama, Shigeru; Srinivasan, Kandadai

    2009-01-01

    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

  9. 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.

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

    KAUST Repository

    Samai, Suman; Sapsanis, Christos; Patil, Sachin; Ezzeddine, Alaa; Moosa, Basem; Omran, Hesham; Emwas, Abdul-Hamid M.; Salama, Khaled N.; Khashab, Niveen M.

    2016-01-01

    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.

  11. QUANTITATION OF MOLECULAR ENDPOINTS FOR THE DOSE-RESPONSE COMPONENT OF CANCER RISK ASSESSMENT

    Science.gov (United States)

    Cancer risk assessment involves the steps of hazard identification, dose-response assessment, exposure assessment and risk characterization. The rapid advances in the use of molecular biology approaches has had an impact on all four components, but the greatest overall current...

  12. Response mechanism for surface acoustic wave gas sensors based on surface-adsorption.

    Science.gov (United States)

    Liu, Jiansheng; Lu, Yanyan

    2014-04-16

    A theoretical model is established to describe the response mechanism of surface acoustic wave (SAW) gas sensors based on physical adsorption on the detector surface. Wohljent's method is utilized to describe the relationship of sensor output (frequency shift of SAW oscillator) and the mass loaded on the detector surface. The Brunauer-Emmett-Teller (BET) formula and its improved form are introduced to depict the adsorption behavior of gas on the detector surface. By combining the two methods, we obtain a theoretical model for the response mechanism of SAW gas sensors. By using a commercial SAW gas chromatography (GC) analyzer, an experiment is performed to measure the frequency shifts caused by different concentration of dimethyl methylphosphonate (DMMP). The parameters in the model are given by fitting the experimental results and the theoretical curve agrees well with the experimental data.

  13. 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.

  14. 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_N_W_F surface. • PP_N_W_F-g-PNVP-PHMG possessed bacterial adhesion-resistant and bactericidal capabilities. • PP_N_W_F-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_N_W_F) 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_N_W_F samples that possess antifouling and antimicrobial properties, have great potential in wound dressing applications.

  15. 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.

  16. Response functions for crystals and surfaces, with applications to surface scattering

    International Nuclear Information System (INIS)

    Barker, J.A.; Steele, W.A.

    1978-01-01

    A general solution of the equations of forced motion of a harmonic crystal or other vibrating system with arbitrary time-dependent forces acting on the atoms is given. The solution is given in terms of dynamical 'response functions', for which expressions in terms of the normal mode frequencies and eigenvectors (polarization vectors) are given. Numerical calculations of the response functions are described for (111) and (100) surfaces of face-centered cubic crystals interacting with Lennard-Jones 6-12 potentials, and the qualitative features of the surface and bulk response functions are discussed. The use of these functions in problems of atomic scattering from surface is outlined, and convenient parametrized forms for this application are given. (Auth.)

  17. Derivation of design response spectra for analysis and testing of components and systems

    International Nuclear Information System (INIS)

    Krutzik, N.

    1996-01-01

    Some institutions participating in the Benchmark Project performed parallel calculations for the WWER-1000 Kozloduy NPP. The investigations were based on various mathematical models and procedures for consideration of soil-structure interaction effects, simultaneously applying uniform soil dynamic and seismological input data. The methods, mathematical models and dynamic response results were evaluated and discussed in detail and finally compared by means of different structural models and soil representations with the aim of deriving final enveloped and smoothed dynamic response data (benchmark response spectra). This should be used for requalification by analysis testing of the mechanical and electrical components and systems located in this type of reactor building

  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. Protein-surface interactions on stimuli-responsive polymeric biomaterials.

    Science.gov (United States)

    Cross, Michael C; Toomey, Ryan G; Gallant, Nathan D

    2016-03-04

    Responsive surfaces: a review of the dependence of protein adsorption on the reversible volume phase transition in stimuli-responsive polymers. Specifically addressed are a widely studied subset: thermoresponsive polymers. Findings are also generalizable to other materials which undergo a similarly reversible volume phase transition. As of 2015, over 100,000 articles have been published on stimuli-responsive polymers and many more on protein-biomaterial interactions. Significantly, fewer than 100 of these have focused specifically on protein interactions with stimuli-responsive polymers. These report a clear trend of increased protein adsorption in the collapsed state compared to the swollen state. This control over protein interactions makes stimuli-responsive polymers highly useful in biomedical applications such as wound repair scaffolds, on-demand drug delivery, and antifouling surfaces. Outstanding questions are whether the protein adsorption is reversible with the volume phase transition and whether there is a time-dependence. A clear understanding of protein interactions with stimuli-responsive polymers will advance theoretical models, experimental results, and biomedical applications.

  20. Stem cell responses to plasma surface modified electrospun polyurethane scaffolds.

    Science.gov (United States)

    Zandén, Carl; Hellström Erkenstam, Nina; Padel, Thomas; Wittgenstein, Julia; Liu, Johan; Kuhn, H Georg

    2014-07-01

    The topographical effects from functional materials on stem cell behavior are currently of interest in tissue engineering and regenerative medicine. Here we investigate the influence of argon, oxygen, and hydrogen plasma surface modification of electrospun polyurethane fibers on human embryonic stem cell (hESC) and rat postnatal neural stem cell (NSC) responses. The plasma gases were found to induce three combinations of fiber surface functionalities and roughness textures. On randomly oriented fibers, plasma treatments lead to substantially increased hESC attachment and proliferation as compared to native fibers. Argon plasma was found to induce the most optimal combination of surface functionality and roughness for cell expansion. Contact guided migration of cells and alignment of cell processes were observed on aligned fibers. Neuronal differentiation around 5% was found for all samples and was not significantly affected by the induced variations of surface functional group distribution or individual fiber topography. In this study the influence of argon, oxygen, and hydrogen plasma surface modification of electrospun polyurethane fibers on human embryonic stem cell and rat postnatal neural stem cell (NSC) responses is studied with the goal of clarifying the potential effects of functional materials on stem cell behavior, a topic of substantial interest in tissue engineering and regenerative medicine. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Central and peripheral components of short latency vestibular responses in the chicken

    Science.gov (United States)

    Nazareth, A. M.; Jones, T. A.

    1998-01-01

    Far-field recordings of short latency vestibular responses to pulsed cranial translation are composed of a series of positive and negative peaks occurring within 10 ms following stimulus onset. In the bird, these vestibular evoked potentials (VsEPs) can be recorded noninvasively and have been shown in the chicken and quail to depend strictly upon the activation of the vestibular component of the eighth nerve. The utility of the VsEP in the study of vestibular systems is dependent upon a clear understanding of the neural sources of response components. The primary aim of the current research in the chicken was to critically test the hypotheses that 1) responses are generated by both peripheral and central neurons and 2) peaks P1 and N1 originate from first order vestibular neurons, whereas later waves primarily depend on activity in higher order neurons. The principal strategy used here was to surgically isolate the eighth nerve as it enters the brainstem. Interruption of primary afferents of the eighth nerve in the brainstem substantially reduced or eliminated peaks beyond P2, whereas P1 and N1 were generally spared. Surgical sections that spared vestibular pathways had little effect on responses. The degree of change in response components beyond N1 was correlated with the extent of damage to central vestibular relays. These findings support the conclusion that responses are produced by both peripheral and central elements of the vestibular system. Further, response peaks later than N1 appear to be dependent upon central relays, whereas P1 and N1 reflect activity of the peripheral nerve. These findings clarify the roles of peripheral and central neurons in the generation of vestibular evoked potentials and provide the basis for a more useful and detailed interpretation of data from vestibular response testing.

  2. Verification of the local structural response of building structures in the anchorage areas of heavy components

    International Nuclear Information System (INIS)

    Krutzik, N.J.; Tropp, R.

    1989-01-01

    In conventional dynamic structural analyses for determining dynamic system response for various locations at which components are installed inside the structures it is common practice (in order to simplify analytical effort) to assume that the anchorage (anchor plate, anchor bolts or throughbolts, concrete and reinforcement in the area of bound) has rigid body characteristics and that the building structure itself does not display any local response of its own. The influence of the stiffness of the anchor plate as well anchor bolts and its stress level on the dynamic response is also neglected. For a large number of anchoring systems, especially for all those components and systems having only a small mass, this assumption is certainly appropriate. At some locations, particularly at points where heavy components are anchored or when loading input has been increased, this can lead to local loading of the anchor system as well as of the building structure well into the nonlinear range. Often, verification of capability to accommodate these loads is not possible without changing the wall thicknesses or increasing the percentage of reinforcement. Since the presence of linear or nonlinear effects can be expected to result in energy dissipation (increase in damping capacity and also a change in the stiffness of the coupled system) it must be assumed that the dynamic response between the theoretical coupling point A and the real connection point B of the component on the anchor plate can be considerably altered. Some changes of the dynamic response in the connection point B have to be expected generally even in cases of linear-elastic loading of the anchorage. Using typical anchoring systems as an example, the influence of consideration of nonlinear effects in the anchorage area of a typical anchor plate on the dynamic response as well as the conservatism of conventional analytical approaches are investigated

  3. Designing Pulse Laser Surface Modification of H13 Steel Using Response Surface Method

    Science.gov (United States)

    Aqida, S. N.; Brabazon, D.; Naher, S.

    2011-01-01

    This paper presents a design of experiment (DOE) for laser surface modification process of AISI H13 tool steel in achieving the maximum hardness and minimum surface roughness at a range of modified layer depth. A Rofin DC-015 diffusion-cooled CO2 slab laser was used to process AISI H13 tool steel samples. Samples of 10 mm diameter were sectioned to 100 mm length in order to process a predefined circumferential area. The parameters selected for examination were laser peak power, overlap percentage and pulse repetition frequency (PRF). The response surface method with Box-Behnken design approach in Design Expert 7 software was used to design the H13 laser surface modification process. Metallographic study and image analysis were done to measure the modified layer depth. The modified surface roughness was measured using two-dimensional surface profilometer. The correlation of the three laser processing parameters and the modified surface properties was specified by plotting three-dimensional graph. The hardness properties were tested at 981 mN force. From metallographic study, the laser modified surface depth was between 37 μm and 150 μm. The average surface roughness recorded from the 2D profilometry was at a minimum value of 1.8 μm. The maximum hardness achieved was between 728 and 905 HV0.1. These findings are significant to modern development of hard coatings for wear resistant applications.

  4. 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.

  5. 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

  6. Precise response function for the magnetic component of gravitational waves in scalar-tensor gravity

    International Nuclear Information System (INIS)

    Corda, Christian

    2011-01-01

    The important issue of the magnetic component of gravitational waves (GWs) has been considered in various papers in the literature. From such analyses, it has been found that such a magnetic component becomes particularly important in the high-frequency portion of the frequency range of ground based interferometers for GWs which arises from standard general theory of relativity (GTR). Recently, such a magnetic component has been extended to GWs arising from scalar-tensor gravity (STG) too. After a review of some important issues on GWs in STG, in this paper we reanalyze the magnetic component in the framework of STG from a different point of view, by correcting an error in a previous paper and by releasing a more precise response function. In this way, we also show that if one neglects the magnetic contribution considering only the low-frequency approximation of the electric contribution, an important part of the signal could be, in principle, lost. The determination of a more precise response function for the magnetic contribution is important also in the framework of the possibility of distinguishing other gravitational theories from GTR. At the conclusion of this paper, an expansion of the main results is also shown in order to recall the presence of the magnetic component in GTR too.

  7. 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.

    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

  8. 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

  9. 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

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

    Science.gov (United States)

    Gao, Rong; Godfrey, Katherine A.; Sufian, Mahir A.

    2017-01-01

    ABSTRACT 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

  11. 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

  12. 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

  13. 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.

  14. Verification of the local structural response of building structures in the anchorage areas of heavy components

    International Nuclear Information System (INIS)

    Krutzik, N.J.; Tropp, R.

    1993-01-01

    In both nuclear and non-nuclear areas of power plants, sections of structures, parts of systems and components are attached to walls and floors by means of anchor plates with bolts, anchor sleeves and bolts and through bolts arranged either in groups or individually. In order to simplify the determination of the transfered vibrations induced by external events (e.g. earthquake, aircraft crash), it is normally assumed that the nodal point between component and concrete possesses rigid body characteristics and the building structure (walls, floors) is also inflexible in the anchorage area. In the course of the parametric studies performed, the nonlinear effects on the anchorage area of a component (in this case an anchor plate and concrete slab) were calculated and the effect of these on the actual vibration behavior and the local structural responses of the building structure at the place of installation of heavy components were investigated. The investigations performed reveal that by taking into account the local behaviour in the anchoring point, it is possible to reduce the dynamic response considerably. More detailed examination of the influence of additional parameters (especially of the geometry of the anchor plates and anchor bolts and their material characteristics) will require further investigations aimed at establishing the characteristics of typical anchor plates. (orig.)

  15. 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.

  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. 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

  18. Effect of SUS316L stainless steel surface conditions on the wetting of molten multi-component oxides ceramic

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jin, E-mail: wangjinustb@gmail.com [Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Fukuoka, 808-0196 (Japan); Matsuda, Nozomu [Bar and Wire Product Unit, Nippon steel and Sumitomo Metal Corporation, Fukuoka, 802-8686 (Japan); Shinozaki, Nobuya [Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Fukuoka, 808-0196 (Japan); Miyoshi, Noriko [The Center for Instrumental Analysis, Kyushu Institute of Technology, Fukuoka, 804-8550 (Japan); Shiraishi, Takanobu [Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, 852-8588 (Japan)

    2015-02-01

    Highlights: • Multi-component oxides had a good wetting on stainless substrates with pretreatments. • Various substrates surface roughness caused the difference of final contact angles. • The wetting rate was slow on polished substrate due to the slow surface oxidation. - Abstract: A study on the effect of SUS316L stainless steel surface conditions on the wetting behavior of molten multi-component oxides ceramic was performed and aimed to contribute to the further understanding of the application of oxides ceramic in penetration treatment of stainless steel coatings and the deposition of stainless steel cermet coatings. The results show that at 1273 K, different surface pre-treatments (polishing and heating) had an important effect on the wetting behavior. The molten multi-component oxides showed good wettability on both stainless steel substrates, however, the wetting process on the polished substrate was significantly slower than that on the heated substrates. The mechanism of the interfacial reactions was discussed based on the microscopic and thermodynamic analysis, the substrates reacted with oxygen generated from the decomposition of the molten multi-component oxides and oxygen contained in the argon atmosphere, and the oxide film caused the molten multi-component oxides ceramic to spread on the substrates surfaces. For the polished substrate, more time was required for the surface oxidation to reach the surface composition of Heated-S, which resulted in relatively slow spreading and wetting rates. Moreover, the variance of the surface roughness drove the final contact angles to slightly different values following the sequence Polished-S > Heated-S.

  19. 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.

  20. 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.

  1. Response of human corneal fibroblasts on silk film surface patterns.

    Science.gov (United States)

    Gil, Eun Seok; Park, Sang-Hyug; Marchant, Jeff; Omenetto, Fiorenzo; Kaplan, David L

    2010-06-11

    Transparent, biodegradable, mechanically robust, and surface-patterned silk films were evaluated for the effect of surface morphology on human corneal fibroblast (hCF) cell proliferation, orientation, and ECM deposition and alignment. A series of dimensionally different surface groove patterns were prepared from optically graded glass substrates followed by casting poly(dimethylsiloxane) (PDMS) replica molds. The features on the patterned silk films showed an array of asymmetric triangles and displayed 37-342 nm depths and 445-3 582 nm widths. hCF DNA content on all patterned films were not significantly different from that on flat silk films after 4 d in culture. However, the depth and width of the grooves influenced cell alignment, while the depth differences affected cell orientation; overall, deeper and narrower grooves induced more hCF orientation. Over 14 d in culture, cell layers and actin filament organization demonstrated that confluent hCFs and their cytoskeletal filaments were oriented along the direction of the silk film patterned groove axis. Collagen type V and proteoglycans (decorin and biglycan), important markers of corneal stromal tissue, were highly expressed with alignment. Understanding corneal stromal fibroblast responses to surface features on a protein-based biomaterial applicable in vivo for corneal repair potential suggests options to improve corneal tissue mimics. Further, the approaches provide fundamental biomaterial designs useful for bioengineering oriented tissue layers, an endemic feature in most biological tissue structures that lead to critical tissue functions.

  2. Molecular dynamics simulation of potentiometric sensor response: the effect of biomolecules, surface morphology and surface charge.

    Science.gov (United States)

    Lowe, B M; Skylaris, C-K; Green, N G; Shibuta, Y; Sakata, T

    2018-05-10

    The silica-water interface is critical to many modern technologies in chemical engineering and biosensing. One technology used commonly in biosensors, the potentiometric sensor, operates by measuring the changes in electric potential due to changes in the interfacial electric field. Predictive modelling of this response caused by surface binding of biomolecules remains highly challenging. In this work, through the most extensive molecular dynamics simulation of the silica-water interfacial potential and electric field to date, we report a novel prediction and explanation of the effects of nano-morphology on sensor response. Amorphous silica demonstrated a larger potentiometric response than an equivalent crystalline silica model due to increased sodium adsorption, in agreement with experiments showing improved sensor response with nano-texturing. We provide proof-of-concept that molecular dynamics can be used as a complementary tool for potentiometric biosensor response prediction. Effects that are conventionally neglected, such as surface morphology, water polarisation, biomolecule dynamics and finite-size effects, are explicitly modelled.

  3. Rumen bacteria: interaction with particulate dietary components and response to dietary variation.

    Science.gov (United States)

    Cheng, K J; Akin, D E; Costerton, J W

    1977-02-01

    The bovine rumen resembles many other ecosystems in that its component bacterial cells are universally surrounded and protected by extracellular structures. The most common form of these structures is a fibrous carbohydrate slime that extends away from the cell and may mediate the attachment of the bacterium to a surface. This attachment is relatively specific and it may occur at the surface of the rumen epithelium or on the cell walls of a specific tissue within the plant-derived food of the animal. The production of the extracellular slime is under nutritional control and slime may be overproduced when soluble carbohydrates are available in high concentration. This overproduction results in cell-cell adhesion among the rumen bacteria with the eventual formation of slime-enclosed microcolonies and, in extreme cases, the generation of sufficient viscosity to cause feedlot bloat.

  4. Saproxylic community, guild and species responses to varying pheromone components of a pine bark beetle.

    Science.gov (United States)

    Etxebeste, Iñaki; Lencina, José L; Pajares, Juan

    2013-10-01

    Some bark beetle species (Coleoptera: Scolytinae) produce aggregation pheromones that allow coordinated attack on their conifer hosts. As a new saproxylic habitat is founded, an assemblage of associated beetles kairomonally respond to bark beetle infochemicals. Ips sexdentatus is one of the major damaging insects of Pinus spp. in Southern Europe. Its response to varying ipsenol (Ie) percentages in relation to ipsdienol (Id) was studied in northwestern Spain, along with the entire saproxylic beetle assemblage captured at multiple-funnel traps. Response profile modeling was undertaken for I. sexdentatus sexes and sex-ratios, associated species and for selected trophic groups using a reference Gaussian model. In addition, the effects on the saproxylic assemblages were analyzed. I. sexdentatus response curve peaked at 22.7% Ie content, while remaining taxa that could be modeled, peaked above ca. 40% Ie. Predator guilds showed a linear relationship with Ie proportion, while competitors showed a delayed response peak. Consequently, species assemblages differed markedly between varying pheromone component mixtures. Given that the evaluated pheromonal proportions mimicked that of logs being colonized by I. sexdentatus, results suggested that the registered differential responses at different levels might provide I. sexdentatus with a temporal window that maximizes conspecific attraction while reducing interference with competitor and predatory guilds. Described responses might help improve the monitoring of the population status of target bark beetles and their associates, but also point toward the by-catch of many natural enemies, as well as rare saproxylic beetle species, interfering with the aims of sustainable forest management.

  5. Fatigue test results of flat plate specimens with surface cracks and evaluation of crack growth in structural components

    International Nuclear Information System (INIS)

    Shibata, Katsuyuki; Yokoyama, Norio; Ohba, Toshihiro; Kawamura, Takaichi; Miyazono, Shohachiro

    1982-12-01

    Part-through surface cracks are most frequently observed in the inspection of structural components, and it is one of the important subjects in the assessment of safety to evaluate appropriately the growth of such cracks during the service life of structural components. Due to the complexity of the stress at the front free surface, the crack growth at the surface shows a different behavior from the other part. Besides, an effect of interaction is caused in the growth of multiple surface cracks. These effects should be included in the growth analysis of surface part-through cracks. Authors have carried out a series of fatigue tests on some kinds of pipes with multiple cracks in the inner surface, and subsequently the fatigue test of flat plate specimens, made of Type 304L stainless steel, with a single or double surface cracks was carried out to study the basic characteristics in the growth of multiple surface cracks. Based on the results of the flat plate test. the correction factors for the front free surface (Cs) and interaction (Ci) of surface cracks were derived quantitatively by the following empirical expressions; Cs = 0.824. Ci = (0.227(a/b) 2 (sec(PI X/2) - 1) + 1)sup(1/m). Using these two correction factors, a procedure to predict the growth of surface cracks was developed by applying the crack growth formula to both the thickness and surface directions. Besides, the crack growth predictions based on the procedure of ASME Code Sex. XI, and the above procedure without the correction of the free surface and interactions on the crack growth behaviors were compared with the test results of flat plate specimens. The crack growth behavior predicted by the procedure described in this report showed the best agreement with the test results in respects of the crack growth life and the change in the crack shape. The criteria of the ASME Code did not agree with the test results. (author)

  6. 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.

  7. Process for surface treatment of zirconium-containing cladding materials for fuel element or other components for nuclear reactors

    International Nuclear Information System (INIS)

    Videm, K.G.; Lunde, L.R.; Kooyman, H.H.

    1975-01-01

    A process for the surface treatment of zirconium-base cladding materials for fuel elements or other components for nuclear reactors is described. The treatment includes pickling the cladding material in a fluoride-containing bath, and then applying a protective coating through oxidation to the pickled cladding material. The fluoride-containing contaminants which remain on the surface of the cladding material during pickling are removed or rendered harmless by anodic oxidation

  8. Multi-Response Optimization of Wire Electrical Discharge Machining for Titanium Grade-5 by Weighted Principal Component Analysis

    Directory of Open Access Journals (Sweden)

    Sachin Ashok Sonawane

    2018-04-01

    Full Text Available This paper reports the results of research to examine the effects of cutting parameters such as pulse-on time, pulse-off time, servo voltage, peak current, wire feed rate and cable tension on surface finish, overcut and metal removal rate (MRR during Wire Electrical Discharge Machining (WEDM of grade-5 titanium (Ti-6Al-4V. Taguchi’s L27 orthogonal design method is used for experimentation. Multi-response optimization is performed by applying weighted principal component analysis (WPCA. The optimum values of cutting variables are found as a pulse on time 118 μs, pulse off time 45 μs, servo voltage 40 volts, peak current 190 Amp. , wire feed rate 5 m/min and cable tension 5 gram. On the other hand, Analysis of Variance (ANOVA, simulation results indicate that pulse-on time is the primary influencing variable which affects the response characteristics contributing 76.00%. The results of verification experiments show improvement in the value of output characteristics at the optimal cutting variables settings. Scanning electron microscopic (SEM analysis of the surface after machining indicates the formation of craters, resolidified material, tool material transfer and increase in the thickness of recast layer at higher values of the pulse on time.

  9. Psychophysical and physiological responses to gratings with luminance and chromatic components of different spatial frequencies.

    Science.gov (United States)

    Cooper, Bonnie; Sun, Hao; Lee, Barry B

    2012-02-01

    Gratings that contain luminance and chromatic components of different spatial frequencies were used to study the segregation of signals in luminance and chromatic pathways. Psychophysical detection and discrimination thresholds to these compound gratings, with luminance and chromatic components of the one either half or double the spatial frequency of the other, were measured in human observers. Spatial frequency tuning curves for detection of compound gratings followed the envelope of those for luminance and chromatic gratings. Different grating types were discriminable at detection threshold. Fourier analysis of physiological responses of macaque retinal ganglion cells to compound waveforms showed chromatic information to be restricted to the parvocellular pathway and luminance information to the magnocellular pathway. Taken together, the human psychophysical and macaque physiological data support the strict segregation of luminance and chromatic information in independent channels, with the magnocellular and parvocellular pathways, respectively, serving as likely the physiological substrates. © 2012 Optical Society of America

  10. PEGylated graphene oxide elicits strong immunological responses despite surface passivation

    Science.gov (United States)

    Luo, Nana; Weber, Jeffrey K.; Wang, Shuang; Luan, Binquan; Yue, Hua; Xi, Xiaobo; Du, Jing; Yang, Zaixing; Wei, Wei; Zhou, Ruhong; Ma, Guanghui

    2017-02-01

    Engineered nanomaterials promise to transform medicine at the bio-nano interface. However, it is important to elucidate how synthetic nanomaterials interact with critical biological systems before such products can be safely utilized in humans. Past evidence suggests that polyethylene glycol-functionalized (PEGylated) nanomaterials are largely biocompatible and elicit less dramatic immune responses than their pristine counterparts. We here report results that contradict these findings. We find that PEGylated graphene oxide nanosheets (nGO-PEGs) stimulate potent cytokine responses in peritoneal macrophages, despite not being internalized. Atomistic molecular dynamics simulations support a mechanism by which nGO-PEGs preferentially adsorb onto and/or partially insert into cell membranes, thereby amplifying interactions with stimulatory surface receptors. Further experiments demonstrate that nGO-PEG indeed provokes cytokine secretion by enhancing integrin β8-related signalling pathways. The present results inform that surface passivation does not always prevent immunological reactions to 2D nanomaterials but also suggest applications for PEGylated nanomaterials wherein immune stimulation is desired.

  11. Identification of chemical components of combustion emissions that affect pro-atherosclerotic vascular responses in mice

    OpenAIRE

    Seilkop, Steven K.; Campen, Matthew J.; Lund, Amie K.; McDonald, Jacob D.; Mauderly, Joe L.

    2012-01-01

    Combustion emissions cause pro-atherosclerotic responses in apolipoprotein E-deficient (ApoE/−) mice, but the causal components of these complex mixtures are unresolved. In studies previously reported, ApoE−/− mice were exposed by inhalation 6 h/day for 50 consecutive days to multiple dilutions of diesel or gasoline exhaust, wood smoke, or simulated “downwind” coal emissions. In this study, the analysis of the combined four-study database using the Multiple Additive Regression Trees (MART) da...

  12. 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)

  13. The modification of equipotential surfaces in the binary systems due to the pressure of the radiation of its components

    International Nuclear Information System (INIS)

    Zorec, Juan; Niemela, Virpi

    1980-01-01

    The modification of the equipotential surfaces of a binary system is studied when the radiation pressure of both components must be taken into account. For suitable values of the radiation parameters, new forms of mass transfer or mass loss may arise [fr

  14. 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.

  15. 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.

  16. Differential Contribution of RNA Interference Components in Response to Distinct Fusarium graminearum Virus Infections.

    Science.gov (United States)

    Yu, Jisuk; Lee, Kyung-Mi; Cho, Won Kyong; Park, Ju Yeon; Kim, Kook-Hyung

    2018-05-01

    The mechanisms of RNA interference (RNAi) as a defense response against viruses remain unclear in many plant-pathogenic fungi. In this study, we used reverse genetics and virus-derived small RNA profiling to investigate the contributions of RNAi components to the antiviral response against Fusarium graminearum viruses 1 to 3 (FgV1, -2, and -3). Real-time reverse transcription-quantitative PCR (qRT-PCR) indicated that infection of Fusarium graminearum by FgV1, -2, or -3 differentially induces the gene expression of RNAi components in F. graminearum Transcripts of the DICER-2 and AGO-1 genes of F. graminearum ( FgDICER-2 and FgAGO-1 ) accumulated at lower levels following FgV1 infection than following FgV2 or FgV3 infection. We constructed gene disruption and overexpression mutants for each of the Argonaute and dicer genes and for two RNA-dependent RNA polymerase (RdRP) genes and generated virus-infected strains of each mutant. Interestingly, mycelial growth was significantly faster for the FgV1-infected FgAGO-1 overexpression mutant than for the FgV1-infected wild type, while neither FgV2 nor FgV3 infection altered the colony morphology of the gene deletion and overexpression mutants. FgV1 RNA accumulation was significantly decreased in the FgAGO-1 overexpression mutant. Furthermore, the levels of induction of FgAGO-1 , FgDICER-2 , and some of the FgRdRP genes caused by FgV2 and FgV3 infection were similar to those caused by hairpin RNA-induced gene silencing. Using small RNA sequencing analysis, we documented different patterns of virus-derived small interfering RNA (vsiRNA) production in strains infected with FgV1, -2, and -3. Our results suggest that the Argonaute protein encoded by FgAGO-1 is required for RNAi in F. graminearum , that FgAGO-1 induction differs in response to FgV1, -2, and -3, and that FgAGO-1 might contribute to the accumulation of vsiRNAs in FgV1-infected F. graminearum IMPORTANCE To increase our understanding of how RNAi components in Fusarium

  17. 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.

  18. Prefrontal cortex activity is associated with biobehavioral components of the stress response

    Directory of Open Access Journals (Sweden)

    Muriah D Wheelock

    2016-11-01

    Full Text Available Contemporary theory suggests that prefrontal cortex (PFC function is associated with individual variability in the psychobiology of the stress response. Advancing our understanding of this complex biobehavioral pathway has potential to provide insight into processes that determine individual differences in stress susceptibility. The present study used functional magnetic resonance imaging (fMRI to examine brain activity during a variation of the Montreal Imaging Stress Task (MIST in fifty-three young adults. Salivary cortisol was assessed as an index of the stress response, trait anxiety was assessed as an index of an individual’s disposition towards negative affectivity, and self-reported stress was assessed as an index of an individual’s subjective psychological experience. Heart rate and skin conductance responses were also assessed as additional measures of physiological reactivity. Dorsomedial PFC, dorsolateral PFC, and inferior parietal lobule demonstrated differential activity during the MIST. Further, differences in salivary cortisol reactivity to the MIST were associated with ventromedial PFC and posterior cingulate activity, while trait anxiety and self-reported stress were associated with dorsomedial and ventromedial PFC activity respectively. These findings underscore that PFC activity regulates behavioral and psychobiological components of the stress response.

  19. 'Faceness' and affectivity: evidence for genetic contributions to distinct components of electrocortical response to human faces.

    Science.gov (United States)

    Shannon, Robert W; Patrick, Christopher J; Venables, Noah C; He, Sheng

    2013-12-01

    The ability to recognize a variety of different human faces is undoubtedly one of the most important and impressive functions of the human perceptual system. Neuroimaging studies have revealed multiple brain regions (including the FFA, STS, OFA) and electrophysiological studies have identified differing brain event-related potential (ERP) components (e.g., N170, P200) possibly related to distinct types of face information processing. To evaluate the heritability of ERP components associated with face processing, including N170, P200, and LPP, we examined ERP responses to fearful and neutral face stimuli in monozygotic (MZ) and dizygotic (DZ) twins. Concordance levels for early brain response indices of face processing (N170, P200) were found to be stronger for MZ than DZ twins, providing evidence of a heritable basis to each. These findings support the idea that certain key neural mechanisms for face processing are genetically coded. Implications for understanding individual differences in recognition of facial identity and the emotional content of faces are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Probabilistic fracture mechanics of nuclear structural components. Consideration of transition from embedded crack to surface crack

    International Nuclear Information System (INIS)

    Yagawa, Genki; Yoshimura, Shinobu; Kanto, Yasuhiro

    1998-01-01

    This paper describes a probabilistic fracture mechanics (PFM) analysis of aged nuclear reactor pressure vessel (RPV) material. New interpolation formulas are first derived for both embedded elliptical surface cracks and semi-elliptical surface cracks. To investigate effects of transition from embedded crack to surface crack in PFM analyses, one of PFM round-robin problems set by JSME-RC111 committee, i.e. 'aged RPV under normal and upset operating conditions' is solved, employing the interpolation formulas. (author)

  1. 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.

  2. 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)

  3. 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.

  4. 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

    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...... cell, or the largest change in the convection pattern, is limited roughly to the region between the previous cell focus and the new cell focus. Outside this region, the ionospheric flows could be greatly enhanced or weakened, while the convection pattern shape changes very little. When B-y is strong...... 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...

  5. Enhanced Production of Cellulase from Pineapple Waste by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    P. Saravanan

    2013-01-01

    Full Text Available Optimization of the media components for cellulase production using Trichoderma reesei was carried out. The optimization of cellulase production using pineapple waste as substrate was performed with statistical methodology based on experimental designs. The screening of nutrients and their influence on the cellulase production was studied using a Plackett-Burman design. Avicel, soybean cake flour, KH2PO4, and yeast extract were found to have the positive influence for the production of cellulase. The selected components were optimized using response surface methodology. The optimum concentrations are avicel: 26.5 g/L, soybean cake flour: 22.5 g/L, KH2PO4: 4.5 g/L, and yeast extract: 12.3 g/L. A maximum cellulase activity of 8.61 IU/mL was obtained under the optimized medium in the validation experiment.

  6. 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

  7. 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...

  8. 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...

  9. 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...

  10. Near surface mechanical properties of optical single crystals and surface response to deterministic microgrinding

    Science.gov (United States)

    Randi, Joseph A., III

    2005-12-01

    This thesis makes use of microindentation, nanoindentation and nanoscratching methods to better understand the mechanical properties of single crystalline silicon, calcium fluoride, and magnesium fluoride. These properties are measured and are used to predict the material's response to material removal, specifically by grinding and polishing, which is a combination of elastic, plastic and fracture processes. The hardness anisotropy during Knoop microindentation, hardness from nanoindentation, and scratch morphology from nanoscratching are reported. This information is related to the surface microroughness from grinding. We show that mechanical property relationships that predict the surface roughness from lapping and deterministic microgrinding of optical glasses are applicable to single crystals. We show the range of hardness from some of the more common crystallographic faces. Magnesium fluoride, having a tetragonal structure, has 2-fold hardness anisotropy. Nanoindentation, as expected provides higher hardness than microindentation, but anisotropy is not observed. Nanoscratching provides the scratch profile during loading, after the load has been removed, and the coefficient of friction during the loading. Ductile and brittle mode scratching is present with brittle mode cracking being orientation specific. Subsurface damage (SSD) measurements are made using a novel process known as the MRF technique. Magnetorheological finishing is used to polish spots into the ground surface where SSD can be viewed. SSD is measured using an optical microscope and knowledge of the spot profile. This technique is calibrated with a previous technique and implemented to accurately measure SSD in single crystals. The data collected are compared to the surface microroughness of the ground surface, resulting in an upper bound relationship. The results indicate that SSD is always less than 1.4 times the peak-to-valley surface microroughness for single crystals regardless of the

  11. Fabrication of highly hydrophobic two-component thermosetting polyurethane surfaces with silica nanoparticles

    Science.gov (United States)

    Yang, Guang; Song, Jialu; Hou, Xianghui

    2018-05-01

    Highly hydrophobic thermosetting polyurethane (TSU) surfaces with micro-nano hierarchical structures were developed by a simple process combined with sandpaper templates and nano-silica embellishment. Sandpapers with grit sizes varying from 240 to 7000 grit were used to obtain micro-scale roughness on an intrinsic hydrophilic TSU surface. The surface wettability was investigated by contact angle measurement. It was found that the largest contact angle of the TSU surface without nanoparticles at 102 ± 3° was obtained when the template was 240-grit sandpaper and the molding progress started after 45 min curing of TSU. Silica nanoparticles modified with polydimethylsiloxane were scattered onto the surfaces of both the polymer and the template to construct the desirable nanostructures. The influences of the morphology, surface composition and the silica content on the TSU surface wettability were studied by scanning electron microscopy (SEM), attenuated total reflection (ATR) infrared (IR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and contact angle measurements. The surface of the TSU/SiO2 nanocomposites containing 4 wt% silica nanoparticles exhibited a distinctive dual-scale structure and excellent hydrophobicity with the contact angle above 150°. The mechanism of wettability was also discussed by Wenzel model and Cassie-Baxter model.

  12. 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

  13. 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...

  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. 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.

  16. Local mechanical stimulation induces components of the pathogen defense response in parsley

    Science.gov (United States)

    Gus-Mayer, Sabine; Naton, Beatrix; Hahlbrock, Klaus; Schmelzer, Elmon

    1998-01-01

    Cell suspension cultures of parsley (Petroselinum crispum) have previously been used as a suitable system for studies of the nonhost resistance response to Phytophthora sojae. In this study, we replaced the penetrating fungus by local mechanical stimulation by using a needle of the same diameter as a fungal hypha, by local application of a structurally defined fungus-derived elicitor, or by a combination of the two stimuli. Similar to the fungal infection hypha, the local mechanical stimulus alone induced the translocation of cytoplasm and nucleus to the site of stimulation, the generation of intracellular reactive oxygen intermediates (ROI), and the expression of some, but not all, elicitor-responsive genes. When the elicitor was applied locally to the cell surface without mechanical stimulation, intracellular ROI also accumulated rapidly, but morphological changes were not detected. A combination of the mechanical stimulus with simultaneous application of low doses of elicitor closely simulated early reactions to fungal infection, including cytoplasmic aggregation, nuclear migration, and ROI accumulation. By contrast, cytoplasmic rearrangements were impaired at high elicitor concentrations. Neither papilla formation nor hypersensitive cell death occurred under the conditions tested. These results suggest that mechanical stimulation by the invading fungus is responsible for the observed intracellular rearrangements and may trigger some of the previously demonstrated changes in the activity of elicitor-responsive genes, whereas chemical stimulation is required for additional biochemical processes. As yet unidentified signals may be involved in papilla formation and hypersensitive cell death. PMID:9653198

  17. 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.

  18. Understanding the biological responses of nanostructured metals and surfaces

    International Nuclear Information System (INIS)

    Lowe, Terry C; A Reiss, Rebecca

    2014-01-01

    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

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

    KAUST Repository

    Julkowska, Magdalena; Koevoets, Iko Tamar; Mol, Selena; Hoefsloot, Huub CJ; Feron, Richard; Tester, Mark A.; Keurentjes, Joost J.B.; Korte, Arthur; Haring, Michel A; de Boer, Gert-Jan; Testerink, Christa

    2017-01-01

    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.

  20. 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.

  1. 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.

  2. Probabilistic fracture mechanics of nuclear structural components: consideration of transition from embedded crack to surface crack

    International Nuclear Information System (INIS)

    Yagawa, G.; Yoshimura, S.

    1999-01-01

    This paper describes a probabilistic fracture mechanics (PFM) analysis of aged nuclear reactor pressure vessel (RPV) material. New interpolation formulas of three-dimensional stress intensity factors are presented for both embedded elliptical surface cracks and semi-elliptical surface cracks. To investigate effects of transition from embedded crack to surface crack in PFM analyses, one of the PFM round-robin problems set by JSME-RC111 committee (i.e. aged RPV under normal and upset operating conditions) is solved, employing the interpolation formulas. (orig.)

  3. Atmospheric boundary layer response to sea surface temperatures during the SEMAPHORE experiment

    Science.gov (United States)

    Giordani, Hervé; Planton, Serge; Benech, Bruno; Kwon, Byung-Hyuk

    1998-10-01

    The sensitivity of the marine atmospheric boundary layer (MABL) subjected to sea surface temperatures (SST) during the Structure des Echanges Mer-Atmosphere, Proprietes des Heterogeneites Oceaniques: Recherche Experimentale (SEMAPHORE) experiment in 1993 has been studied. Atmospheric analyses produced by the Action de Recherche, Petite Echelle, Grande Echelle (ARPEGE) operational model at the French meteorological weather service assimilated data sets collected between October 7 and November 17, 1993, merged with the Global Telecommunication System (GTS) data. Analyses were validated against independent data from aircraft instruments collected along a section crossing the Azores oceanic front, not assimilated into the model. The responses of the mean MABL in the aircraft cross section to changes in SST gradients of about 1°C/100 km were the presence of an atmospheric front with horizontal gradients of 1°C/100 km and an increase of the wind intensity from the cold to the warm side during an anticyclonic synoptic situation. The study of the spatiotemporal characteristics of the MABL shows that during 3 days of an anticyclonic synoptic situation the SST is remarkably stationary because it is principally controlled by the Azores ocean current, which has a timescale of about 10 days. However, the temperature and the wind in the MABL are influenced by the prevailing atmospheric conditions. The ocean does not appear to react to the surface atmospheric forcing on the timescale of 3 days, whereas the atmospheric structures are modified by local and synoptic-scale advection. The MABL response appears to be much quicker than that of the SSTs. The correlation between the wind and the thermal structure in the MABL is dominated by the ageostrophic and not by the geostrophic component. In particular, the enhancement of the wind on either side of the SST front is mainly due to the ageostrophic component. Although the surface heat fluxes are not the only cause of ageostrophy, the

  4. 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

  5. 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...

  6. 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)

  7. Surface Quality Improvement of AA6060 Aluminum Extruded Components through Liquid Nitrogen Mold Cooling

    Directory of Open Access Journals (Sweden)

    Andrea Francesco Ciuffini

    2018-06-01

    Full Text Available 6xxx aluminum alloys are suitable for the realization of both structural applications and architectural decorative elements, thanks to the combination of high corrosion resistance and good surface finish. In areas where the aesthetic aspects are fundamental, further improvements in surface quality are significant. The cooling of the extrusion mold via internal liquid nitrogen fluxes is emerging as an important innovation in aluminum extrusion. Nowadays, this innovation is providing a large-scale solution to obtain high quality surface finishes in extruded aluminum semi-finished products. These results are also coupled to a significant increase in productivity. The aim of the work is to compare the surface quality of both cooled liquid nitrogen molds and classically extruded products. In this work, adhesion phenomena, occurring during the extrusion between the mold and the flowing material, have been detected as the main causes of the presence of surface defects. The analysis also highlighted a strong increase in the surface quality whenever the extrusion mold was cooled with liquid nitrogen fluxes. This improvement has further been confirmed by an analysis performed on the finished products, after painting and chromium plating. This work on the AA6060 alloy has moreover proceeded to roughness measurements and metallographic analyses, to investigate the eventual occurrence of other possible benefits stemming from this new extrusion mold cooling technology.

  8. 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.

  9. 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

  10. Thermal memory influence on the thermoconducting component of indirect photoacoustic response

    International Nuclear Information System (INIS)

    Nešić, M; Popović, M; Gusavac, P; Šoškić, Z; Galović, S

    2012-01-01

    In this paper, a model of the thermoconducting component of the indirect photoacoustic (PA) response is derived that includes thermal memory properties of the examined material and its fluid environment. A comparison is made between the derived model and the classic one, which neglects the influence of thermal memory. It has been shown that, at modulation frequencies lower than a certain boundary frequency of the light source, these models tend to overlap, while at higher frequencies, noticeable differences occur. The boundary frequency depends on heat propagation velocity through the sample and its thickness. This observation limits the validity domain of previous models to a range lower than the boundary frequency, offering, at the same time, the possibility of obtaining thermal memory properties using PA effects at frequencies above it.

  11. 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

  12. 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.

  13. 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.

  14. Habituation of the cold shock response may include a significant perceptual component.

    Science.gov (United States)

    Barwood, Martin J; Corbett, Jo; Wagstaff, Christopher R D

    2014-02-01

    Accidental immersion in cold water is a risk factor for many occupations. Habituation to cold-water immersion (CWI) is one practical means of reducing the cold shock response (CSR) on immersion. We investigated whether repeated thermoneutral water immersion (TWI) induced a perceptual habituation (i.e., could lessen perceived threat and anxiety) and consequently reduce the CSR on subsequent CWI. There were 12 subjects who completed seven 7-min head-out immersions. Immersions one and seven were CWls [15.0 (0.1) degrees C], and immersions two to six were TWI [34.9 (0.10) degrees C]. Anxiety 120-cm visual analogue scale) and the cardiorespiratory responses [heart rate (f(C)), respiratory frequency (f(R)), tidal volume (V(T)), and minute ventilation (V(E))] to immersion were measured throughout. Data were compared within subject between conditions using ANOVA to an alpha level of 0.05. Acute anxiety was significantly reduced after repeated exposure to the immersion scenario (i.e., TWI): CWI-1: 6.3 (4.4) cm; and CWI-2: 4.5 (4.0) cm [condition mean (SD)]. These differences did not influence the peak in the CSR. The f(C), f(R), and V(E) responses were similar between CWI-1 and CWI-2. V(T) response was significantly lower in CWI-2; mean (SD) across the immersion: CWI-1 1.27 (0.17) vs. CWI-2 1.11 0.21 L. Repeated TWI lessened the anxiety associated with CWI (perceptual habituation). This had a negligible effect on the primary components of the CSR, but did lower VT, which may reduce the volume of any aspirated water in an emergency situation. Reducing the threat appraisal of an environmental stressor may be a useful biproduct of survival training, thereby minimizing psychophysiological strain.

  15. Interactions among spectral components of radiation in the growth responses of rice, tomato and strawberry

    International Nuclear Information System (INIS)

    Inada, K.; Matsuno, A.

    1985-01-01

    Effects of spectral components and their ratios of radiation on simultaneous growth responses were investigated with rice, tomato and strawberry plants exposed to lights with a high fluence rate (350 or 408 μmol m -2 s -1 , 400-700 nm) during every daytime. Both elongation growth and Ieaf area development in rice and strawberry were promoted by red (R) but inhibited by blue (B) component depending on the each fluence rate. However, leaf area in tomato responded in opposite direction to these. The elongation growth was remarkably increased with the fluence rate of far-red (FR) in tomato and strawberry, but not in rice. These responses were lineary increased, except FR and UV effects, with logarithmic R/B ratio in rice and strawberry but not in tomato. A very low R/FR ratio caused a strong promotion of both elongation and leaf area in tomato, while it promoted petiole elengation but inhibited leaf area development in strawberry. The elongation and leaf area development responded to R/FR in reverse way between rice and strawberry. Chlorophyll content of leaves was generally decreased with the increase of logarithmic R/B ratio in all the species. Areal weight of leaf and dry weight increment/leaf area were more or less increased with R/B and R/ FR ratios, Dry weight increment varied with the spectral ratios in almost the same way as leaf area, suggesting that spectral dependence of photosynthetic production was not much different between the species. Some discussions were made on the photoreceptor pigments involved in the elongation growth and leaf area development, and on the selection of light quantity to ensure a normal growth of each plant species

  16. Modulation of expression of HLA components at the cell surface induced by anti-β2m reagents

    International Nuclear Information System (INIS)

    Ceppellini, R.; Malavasi, F.; Garotta, G.; Trucco, M.

    1981-01-01

    Antibodies against lymphocyte surface components are able to rearrange profoundly the topography of the cell membrane with a different modulation of surface antigens. Of particular interest is the effect of anti-β2m reagents, which are able to suppress completely the reactivity of epitopes carried by the two chains of the ABC dimers, while the expressivity of other antigens, such as DR, is significantly increased. These results have been obtained with immunoradiobinding under a varity of conditions, thus confirming the validity of the ''bb'' (β2m blanketing) test. (author)

  17. The surface distribution of chemical anomalies of Ap components in detached close binaries

    International Nuclear Information System (INIS)

    Kitamura, M.

    1980-01-01

    By estimating the orbital inclinations of non-eclipsing detached close binaries with Ap spectra, a marked statistical preference is obtained on the frequency distribution of the inclination which suggests that the abundance anomalies of Ap components tend to concentrate towards the stellar polar region. (Auth.)

  18. 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

    The possibility of measuring multi-material components, while assessing inner and outer features simultaneously makes X-ray computed tomography (CT) the latest evolution in the field of coordinate measurement systems (CMSs). However, the difficulty in selecting suitable scanning parameters and su...

  19. Relative response of TL and component-resolved OSL to alpha and beta radiations in annealed sedimentary quartz

    International Nuclear Information System (INIS)

    Polymeris, George S.; Afouxenidis, Dimitrios; Raptis, Spyridoula; Liritzis, Ioannis; Tsirliganis, Nestor C.; Kitis, George

    2011-01-01

    Knowledge of the relative luminescence response to alpha and beta radiation is very important in TL and OSL dating. In the present study the relative alpha to beta response is studied in a sedimentary quartz sample, previously fired at 900 deg. C for 1 h, in the dose region between 1 and 128 Gy, for both thermoluminescence (TL) and linearly modulated optically stimulated luminescence (LM - OSL). The LM - OSL measurements were performed at room temperature and at 125 deg. C. All OSL signals were deconvolved into their individual components. Comparison of OSL curves after alpha and beta irradiation strongly supports that quartz OSL components follow first order kinetics in both cases. In the case of TL, the relative alpha to beta response is found to be very different for each TL glow-peak, but it does not depend strongly on irradiation dose. In the case of LM - OSL measurements, it is found that the relative behaviour of the alpha to beta response is different for three distinct regions, namely the fast OSL component, the region of medium OSL component originating from the TL glow-peak at 110 deg. C when stimulation takes place at room temperature and finally the region of slow OSL component. Following stimulation at ambient temperature, the relative alpha to beta response of all components was not observed to depend significantly on dose, with the value of ratio being 0.03 and a tendency to decrease with increasing dose. However, in the case of measurements performed at 125 deg. C, the relative response of the fast components is much enhanced, and for the remaining components it increases with increasing dose. Special care must be taken to examine the relative alpha to beta response of the fast component at 125 deg. C which contrasts the relative response of the TL peak at ca. 325 deg. C. The implications for the dating of annealed quartz are also briefly discussed. - Highlights: → Relative alpha to beta response for TL and LM-OSL is studied in annealed

  20. 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.

  1. 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.

  2. 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 (<1 mm) and ultra-high time resolution (<2 s for EAST measuring conditions). Three main components of the DUT-SIEP are all integrated and synchronized by a time schedule control and data acquisition terminal and coupled with a three-dimensional phase unwrapping algorithm, the surface morphology information of target samples can be obtained and reconstructed in real-time. A local surface morphology of the real divertor

  3. 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.

  4. Effect of surface roughness and surface modification of indium tin oxide electrode on its potential response to tryptophan

    International Nuclear Information System (INIS)

    Khan, Md. Zaved Hossain; Nakanishi, Takuya; Kuroiwa, Shigeki; Hoshi, Yoichi; Osaka, Tetsuya

    2011-01-01

    Highlights: → We examine factors affecting potential response of ITO electrode to tryptophan. → Surface roughness of ITO electrode affects the stability of its rest potential. → Surface modification is effective for ITO electrode with a certain roughness. → Optimum values of work function exist for potential response of ITO to tryptophan. - Abstract: The effect of surface modification of indium tin oxide (ITO) electrode on its potential response to tryptophan was investigated for ITO substrates with different surface roughness. It was found that a small difference in surface roughness, between ∼1 and ∼2 nm of R a evaluated by atomic force microscopy, affects the rest potential of ITO electrode in the electrolyte. A slight difference in In:Sn ratio at the near surface of the ITO substrates, measured by angle-resolved X-ray photoelectron spectrometry and Auger electron spectroscopy is remarkable, and considered to relate with surface roughness. Interestingly, successive modification of the ITO surface with aminopropylsilane and disuccinimidyl suberate, of which essentiality to the potential response to indole compounds we previously reported, improved the stability of the rest potential and enabled the electrodes to respond to tryptophan in case of specimens with R a values ranging between ∼2 and ∼3 nm but not for those with R a of ∼1 nm. It was suggested that there are optimum values of effective work function of ITO for specific potential response to tryptophan, which can be obtained by the successive modification of ITO surface.

  5. 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

    . In order to implement the traceability ofthe manufacturing process, the geometry and dimension of the micro structure on the tool and the replica were assessed viametrological methods. The functionality of the anisotropic surfaces on the polymer replicas were evaluated by a gonioreflectometerand image...

  6. On the application of response surface methodology for predicting and optimizing surface roughness and cutting forces in hard turning by PVD coated insert

    Directory of Open Access Journals (Sweden)

    Hessainia Zahia

    2015-04-01

    Full Text Available This paper focuses on the exploitation of the response surface methodology (RSM to determine optimum cutting conditions leading to minimum surface roughness and cutting force components. The technique of RSM helps to create an efficient statistical model for studying the evolution of surface roughness and cutting forces according to cutting parameters: cutting speed, feed rate and depth of cut. For this purpose, turning tests of hardened steel alloy (AISI 4140 (56 HRC were carried out using PVD – coated ceramic insert under different cutting conditions. The equations of surface roughness and cutting forces were achieved by using the experimental data and the technique of the analysis of variance (ANOVA. The obtained results are presented in terms of mean values and confidence levels. It is shown that feed rate and depth of cut are the most influential factors on surface roughness and cutting forces, respectively. In addition, it is underlined that the surface roughness is mainly related to the cutting speed, whereas depth of cut has the greatest effect on the evolution of cutting forces. The optimal machining parameters obtained in this study represent reductions about 6.88%, 3.65%, 19.05% in cutting force components (Fa, Fr, Ft, respectively. The latters are compared with the results of initial cutting parameters for machining AISI 4140 steel in the hard turning process.

  7. 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

  8. 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.

  9. 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)

  10. Optimization of galacto-oligosacharides synthesis using response surface methodology

    Directory of Open Access Journals (Sweden)

    Carević Milica B.

    2017-01-01

    Full Text Available Galacto-oligosaccharides (GOS are important lactose-derived compounds, considered to be a prebiotics, based on abundant scientific evidence about their unique physical properties and physiological effects. This consequently allows their widespread application as supplement in food and feed industry. They are preferably produced by the enzymatic transgalactosylation action of β-galactosidase. However, this enzyme simultaneously performs its primary biological function of lactose hydrolysis, and it is of crucial importance to gain an insight into the influence of different reaction conditions, and provide favorization of transgalactosylation, particularly GOS synthesis reaction. In this study, the response surface methodology (RSM was applied in terms of individual experimental factors effect estimation, their mutual interaction identification and finally, the determination of optimum conditions for highest GOS yield achievement. Having said that, it can be observed that the temperature and pH have no significant impact on the GOS yield, while on the other hand, the lactose concentration of 400 g/l, enzyme concentration of 13.5 g/l and reaction time of 13 min represent the optimum conditions for achieving the highest GOS yields.

  11. 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.

  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. 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.

  14. 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)

  15. 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

  16. A Conserved Two-Component Signal Transduction System Controls the Response to Phosphate Starvation in Bifidobacterium breve UCC2003.

    NARCIS (Netherlands)

    Alvarez-Martin, P.; Fernandez, M.; O'Connell-Motherway, M.; O'Connell, K.J.; Sauvageot, N.; Fitzgerald, G.F.; Macsharry, J.; Zomer, A.L.; Sinderen, D. van

    2012-01-01

    This work reports on the identification and molecular characterization of the two-component regulatory system (2CRS) PhoRP, which controls the response to inorganic phosphate (P(i)) starvation in Bifidobacterium breve UCC2003. The response regulator PhoP was shown to bind to the promoter region of

  17. 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

  18. Study of the pyritized surfaces of the carbon steel components in heavy water production facilities

    International Nuclear Information System (INIS)

    Radulescu, Maria; Parvan, Ioana; Lucan, Dumitra; Fulger, Manuela; Dinu, Alice; Blanatui, A.

    1998-01-01

    The components used in the Girldler Sulfide (GS) process of heavy water production are made of carbon steel covered by iron sulfide layers of different compositions (mackinawite, troilite, pyrrhotite or pyrite) of variable thicknesses. The most protective layers which provide an acceptable corrosion resistance of the subjacent metal are the mixtures of pyrrhotite and pyrite. In the present work, the corrosion resistance of carbon steel samples covered by different types of sulfides was investigated by the following methods: X ray diffraction, metallography and electrochemical methods (potential-dynamical and electrochemical impedance). In order to carry out the electrochemical measurements in the same conditions as those of the operation of carbon steel components in D 2 O production facilities, the experiments were performed with Na 2 S solutions, at pH=4 - 13 and S 2- concentration value between 1 and 1000 mg/l. The dependence of corrosion rate kinetics on pH and S 2- concentration of the testing solution was investigated for sulfide covered samples comparatively with the uncovered ones. Corrosion rates determined gravimetrically were compared with those determined by electrochemical measurements. The uniformity and thickness of the sulfide layers were checked by metallographic methods. The composition of the sulfides formed in various environment conditions was established by X-ray diffraction. Reaction mechanisms specific for sulfide formation environments have been proposed. (authors)

  19. 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.

  20. 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...

  1. Flow Components in a NaK Test Loop Designed to Simulate Conditions in a Nuclear Surface Power Reactor

    Science.gov (United States)

    Polzin, Kurt A.; Godfroy, Thomas J.

    2008-01-01

    A test loop using NaK as the working fluid is presently in use to study material compatibility effects on various components that comprise a possible nuclear reactor design for use on the lunar surface. A DC electromagnetic (EM) pump has been designed and implemented as a means of actively controlling the NaK flow rate through the system and an EM flow sensor is employed to monitor the developed flow rate. These components allow for the matching of the flow rate conditions in test loops with those that would be found in a full-scale surface-power reactor. The design and operating characteristics of the EM pump and flow sensor are presented. In the EM pump, current is applied to a set of electrodes to produce a Lorentz body force in the fluid. A measurement of the induced voltage (back-EMF) in the flow sensor provides the means of monitoring flow rate. Both components are compact, employing high magnetic field strength neodymium magnets thermally coupled to a water-cooled housing. A vacuum gap limits the heat transferred from the high temperature NaK tube to the magnets and a magnetically-permeable material completes the magnetic circuit. The pump is designed to produce a pressure rise of 5 psi, and the flow sensor's predicted output is roughly 20 mV at the loop's nominal flow rate of 0.5 GPM.

  2. 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.

  3. The response of parental components of ZP maize hybrids to effects of herbicides

    Directory of Open Access Journals (Sweden)

    Stefanović Lidija

    2007-01-01

    Full Text Available The response of four inbred lines, parental components of ZP maize hybrids, to effects of six herbicides applied after emergence of both, maize and weeds, was observed in the present study. The following herbicides were applied in the 2-3-leaf stage of maize: isoxaflutole (Merlin 750-WG in the amount of 0.135 kg ha-1, nicosulfuron (Motivell in the amount of 1.25 l ha-1, foramsulfuron (Equip in the amount of 2.0 l ha-1, dicamba + rimsulfuron (Tarot plus in the amount of 0.3 kg ha-1, mezotrion (Callisto in the amount of 0.25 l ha-1 and thifensulfuron-methyl (Grid in the amount of 0.02 kg ha-1. The phytotoxic effect of herbicides on the maize grain yield was evaluated according to the 1-9 EWRC scale. Maize inbreds showed different susceptibility depending on the applied herbicide. The least favourable effects in both years for all genotypes were obtained in the treatments with Tarot plus and Grid, in which the lowest values of maize grain yield were recorded.

  4. The Physiological Basis and Clinical Use of the Binaural Interaction Component of the Auditory Brainstem Response

    Science.gov (United States)

    Klump, Georg M.; Tollin, Daniel J.

    2016-01-01

    The auditory brainstem response (ABR) is a sound-evoked non-invasively measured electrical potential representing the sum of neuronal activity in the auditory brainstem and midbrain. ABR peak amplitudes and latencies are widely used in human and animal auditory research and for clinical screening. The binaural interaction component (BIC) of the ABR stands for the difference between the sum of the monaural ABRs and the ABR obtained with binaural stimulation. The BIC comprises a series of distinct waves, the largest of which (DN1) has been used for evaluating binaural hearing in both normal hearing and hearing-impaired listeners. Based on data from animal and human studies, we discuss the possible anatomical and physiological bases of the BIC (DN1 in particular). The effects of electrode placement and stimulus characteristics on the binaurally evoked ABR are evaluated. We review how inter-aural time and intensity differences affect the BIC and, analyzing these dependencies, draw conclusion about the mechanism underlying the generation of the BIC. Finally, the utility of the BIC for clinical diagnoses are summarized. PMID:27232077

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. Improved low frequency room responses by considering finiteness of room boundary surfaces

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho

    2013-01-01

    surface impedance values that are assigned to all the boundary surfaces, the suggested reflection coefficient is found to improve low frequency responses compared to the infinite panel theory; larger improvements are found for a more disproportionate room, more absorptive surfaces, and surfaces having...

  12. Effects of non-uniform temperature gradients on surface tension driven two component magneto convection in a porous- fluid system

    Science.gov (United States)

    Manjunatha, N.; Sumithra, R.

    2018-04-01

    The problem of surface tension driven two component magnetoconvection is investigated in a Porous-Fluid system, consisting of anincompressible two component electrically conducting fluid saturatedporous layer above which lies a layer of the same fluid in the presence of a uniform vertical magnetic field. The lower boundary of the porous layeris rigid and the upper boundary of the fluid layer is free with surfacetension effects depending on both temperature and concentration, boththese boundaries are insulating to heat and mass. At the interface thevelocity, shear and normal stress, heat and heat flux, mass and mass fluxare assumed to be continuous suitable for Darcy-Brinkman model. Theeigenvalue problem is solved in linear, parabolic and inverted parabolictemperature profiles and the corresponding Thermal Marangoni Numberis obtained for different important physical parameters.

  13. 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.

  14. 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.

  15. A Smart Superwetting Surface with Responsivity in Both Surface Chemistry and Microstructure.

    Science.gov (United States)

    Zhang, Dongjie; Cheng, Zhongjun; Kang, Hongjun; Yu, Jianxin; Liu, Yuyan; Jiang, Lei

    2018-03-26

    Recently, smart surfaces with switchable wettability have aroused much attention. However, only single surface chemistry or the microstructure can be changed on these surfaces, which significantly limits their wetting performances, controllability, and applications. A new surface with both tunable surface microstructure and chemistry was prepared by grafting poly(N-isopropylacrylamide) onto the pillar-structured shape memory polymer on which multiple wetting states from superhydrophilicity to superhydrophobicity can be reversibly and precisely controlled by synergistically regulating the surface microstructure and chemistry. Meanwhile, based on the excellent controllability, we also showed the application of the surface as a rewritable platform, and various gradient wettings can be obtained. This work presents for the first time a surface with controllability in both surface chemistry and microstructure, which starts some new ideas for the design of novel superwetting materials. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  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. 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.

  18. Media optimization for laccase production by Trichoderma harzianum ZF-2 using response surface methodology.

    Science.gov (United States)

    Gao, Huiju; Chu, Xiang; Wang, Yanwen; Zhou, Fei; Zhao, Kai; Mu, Zhimei; Liu, Qingxin

    2013-12-01

    Trichoderma harzianum ZF-2 producing laccase was isolated from decaying samples from Shandong, China, and showed dye decolorization activities. The objective of this study was to optimize its culture conditions using a statistical analysis of its laccase production. The interactions between different fermentation parameters for laccase production were characterized using a Plackett-Burman design and the response surface methodology. The different media components were initially optimized using the conventional one-factor-at-a-time method and an orthogonal test design, and a Plackett-Burman experiment was then performed to evaluate the effects on laccase production. Wheat straw powder, soybean meal, and CuSO4 were all found to have a significant influence on laccase production, and the optimal concentrations of these three factors were then sequentially investigated using the response surface methodology with a central composite design. The resulting optimal medium components for laccase production were determined as follows: wheat straw powder 7.63 g/l, soybean meal 23.07 g/l, (NH4)2SO4 1 g/l, CuSO4 0.51 g/l, Tween-20 1 g/l, MgSO4 1 g/l, and KH2PO4 0.6 g/l. Using this optimized fermentation method, the yield of laccase was increased 59.68 times to 67.258 U/ml compared with the laccase production with an unoptimized medium. This is the first report on the statistical optimization of laccase production by Trichoderma harzianum ZF-2.

  19. On the Application of Replica Molding Technology for the Indirect Measurement of Surface and Geometry of Micromilled Components

    DEFF Research Database (Denmark)

    Baruffi, Federico; Parenti, Paolo; Cacciatore, Francesco

    2017-01-01

    the replica molding technology. The method consists of obtaining a replica of the feature that is inaccessible for standard measurement devices and performing its indirect measurement. This paper examines the performance of a commercial replication media applied to the indirect measurement of micromilled...... components. Two specifically designed micromilled benchmark samples were used to assess the accuracy in replicating both surface texture and geometry. A 3D confocal microscope and a focus variation instrument were employed and the associated uncertainties were evaluated. The replication method proved...... to be suitable for characterizing micromilled surface texture even though an average overestimation in the nano-metric level of the Sa parameter was observed. On the other hand, the replicated geometry generally underestimated that of the master, often leading to a different measurement output considering...

  20. Binding of a cementum attachment protein to extracellular matrix components and to dental surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Pitaru, S; Hekmati, H [Department of Oral Biology, Goldschleger School of Dental Medicine, Tel Aviv University (Israel); Savion, N [Goldschleger Eye Institute, Sackler School of Medicine, Tel Aviv University (Israel); Olsen, S; Narayanan, S A [Department of Pathology, School of Medicine, University of Washington, Seattle, Washington (United States)

    1992-01-01

    Cementum proteins (CP) have been shown to mediate cell attachment. Among these, a 55 kDa protein was isolated. The purpose of the present study was to assess the capacity of CP to bind to non-demineralized and demineralized root surfaces and to support cell attachment to dentin. CP were prepared by sequential extraction of bovine cementum with 25 mM EDTA, 0.5 M acetic acid followed by 4 M guanidine HCl. The latter was subjected to ion exchange chromatography on a DEAE-3SW column and eluted stepwise with a 0-0.5 M NaCl gradient. CP were labelled with [sup 125]I and the capacity of [sup 125]I-CP to bind to mineralized and partially demineralized dentin, synthetic hydroxyapatite, collagen, fibronectin and fibrillar collagen-fibronectin cimplex was assessed. It was found that CP bind specifically to mineralized dentin and synthetic hydroxyapatite but not to demineralized dentin. The specific binding was 60% of the total binding. SDS-PAGE analysis of the proteins bound to dentin indicated that the main bound protein had a molecular weight of 55 kDa. CP exhibited high affinity for fibronectin (k[sub D] = 1.56 x 10[sup -10] M) and fibronectincollagen complex, but their binding to either molecular or fibrillar collagen was negligible. It is suggested that CP may play an important role in the attachment of cells of the periodontium to cementum extracellular matrix during homeostasis and regeneration. (au).

  1. 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.

  2. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kreider, Alexej; Richter, Katharina; Sell, Stephan; Fenske, Mandus; Tornow, Christian; Stenzel, Volkmar [Fraunhofer Institute for Manufacturing Technology and Advanced Materials - IFAM, Wiener Strasse 12, 28359 Bremen (Germany); Grunwald, Ingo, E-mail: ingo.grunwald@ifam.fraunhofer.de [Fraunhofer Institute for Manufacturing Technology and Advanced Materials - IFAM, Wiener Strasse 12, 28359 Bremen (Germany)

    2013-05-15

    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.

  4. 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.

  5. 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...

  6. 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...

  7. 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.

  8. 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.

  9. 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

  10. 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

  11. 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.

  12. 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

  13. Effect of the ODS-4 surfactant and its components on the efficiency of decontamination of solid surfaces

    International Nuclear Information System (INIS)

    Dvorak, J.; Duris, P.

    1994-01-01

    The efficiency was examined of the desorption of carrier-free traces of 147 Pm adsorbed from an acid aqueous solution at pH 2.6 in static conditions on a paint routinely applied to military facilities. The desorption was performed by using the ODS-4 decontamination and deactivation mixture and its components at various concentrations. It is concluded that the surfactant is not very well suited to the decontamination of solid surfaces contaminated with radionuclides which form the water-soluble component of radioactive contamination (in dependence on pH). This is due to the composition and the associated high alkalinity of the ODS-4 agent, which, however, is necessary if detoxication of toxic agents is required. In practice, however, the efficiency of decontamination will be appreciably higher because the military decontamination procedures involve dynamic (mechanical) treatment of the surfaces using brushes with flowing liquid, pressure application of the surfactant and water, moving baths, etc. (P.A.). 7 tabs., 2 figs., 10 refs

  14. 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.

  15. Temperature-Responsive Anisotropic Slippery Surface for Smart Control of the Droplet Motion.

    Science.gov (United States)

    Wang, By Lili; Heng, Liping; Jiang, Lei

    2018-02-28

    Development of stimulus-responsive anisotropic slippery surfaces is important because of the high demand for such materials in the field of liquid directional-driven systems. However, current studies in the field of slippery surfaces are mainly conducted to prepare isotropic slippery surfaces. Although we have developed electric-responsive anisotropic slippery surfaces that enable smart control of the droplet motion, there remain challenges for designing temperature-responsive anisotropic slippery surfaces to control the liquid droplet motion on the surface and in the tube. In this work, temperature-responsive anisotropic slippery surfaces have been prepared by using paraffin, a thermo-responsive phase-transition material, as a lubricating fluid and directional porous polystyrene (PS) films as the substrate. The smart regulation of the droplet motion of several liquids on this surface was accomplished by tuning the substrate temperature. The uniqueness of this surface lies in the use of an anisotropic structure and temperature-responsive lubricating fluids to achieve temperature-driven smart control of the anisotropic motion of the droplets. Furthermore, this surface was used to design temperature-driven anisotropic microreactors and to manipulate liquid transfer in tubes. This work advances the understanding of the principles underlying anisotropic slippery surfaces and provides a promising material for applications in the biochip and microreactor system.

  16. Liquid crystal elastomer coatings with programmed response of surface profile

    NARCIS (Netherlands)

    Babakhanova, G.; Turiv, T.; Guo, Y.; Hendrikx, M.; Wei, Q.H.; Schenning, A.P.H.J.; Broer, D.J.; Lavrentovich, O.D.

    2018-01-01

    Stimuli-responsive liquid crystal elastomers with molecular orientation coupled to rubber-like elasticity show a great potential as elements in soft robotics, sensing, and transport systems. The orientational order defines their mechanical response to external stimuli, such as thermally activated

  17. Overload protection: avoidance response to heavy plantar surface loading.

    Science.gov (United States)

    Robbins, S E; Hanna, A M; Gouw, G J

    1988-02-01

    Current footwear which are designed for use in running are examples of intentional biomechanical model integration into device design. The inadequacy of this footwear in protecting against injury is postulated to be due to fixation on inadequate models of locomotory biomechanics that do not provide for feedback control; in particular, an hypothesized plantar surface sensory-mediated feedback control system, which imparts overload protection during locomotion. A heuristic approach was used to identify the hypothesized system. A random series of loads (0 to 164 kg) was applied to the knee flexed at 90 degrees. In this testing system, plantar surface avoidance behavior was the difference between the sum of the leg weight and the load applied to the knee, and the load measured at the plantar surface; this was produced by activation of hip flexors. Significant avoidance behavior was found in all of the subjects (P less than 0.001). On all surfaces tested, including modern athletic footwear (P less than 0.001), its magnitude increased directly in relation to the load applied to the knee (P less than 0.001). There were significant differences in avoidance behavior in relation to the weight-bearing surfaces tested (P less than 0.05). With the identification of a feedback control system which would serve to moderate loading during locomotion, an explanation is provided as to why current athletic footwear do not protect and may be injurious; thus allowing the design of footwear which may be truly protective.

  18. 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.

  19. 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.

  20. Effect of heat treatment in air on surface composition of iron-phosphate based soft magnetic composite components

    Energy Technology Data Exchange (ETDEWEB)

    Oikonomou, C., E-mail: christos.oikonomou@chalmers.se; Oro, R.; Hryha, E.; Nyborg, L.

    2014-11-15

    Highlights: • Surface morphological and chemical depth profiling analyses of SMC parts. • Effect of annealing at exterior/interior areas for different temperature regimes. • Difference in degree of oxidation/nature of bulk/coating with area and temperature. • Thermodynamic calculations/considerations on the thermal stability of the coating. • Incomplete delubrication and strong bulk oxidation of the samples under 500 °C. - Abstract: Soft magnetic composite materials (SMC) manufactured by conventional powder metallurgical techniques for electromagnetic applications constitute individually encapsulated ferromagnetic powder particles with an insulating surface layer, bonded together into 3D finished structures. The production procedure includes compaction of the SMC base powder mixed with a lubricant substance and a post-annealing treatment that aims to relieve the stresses induced in the component during pressing. In the present study, the effect of the heat treatment process to the nature of the insulating layer was investigated under different temperature regimes using analytical techniques. Its surface chemistry was determined based on the XPS depth profiling technique, and its morphology and structure were evaluated using HR-SEM and XRD. Differences between interior and exterior areas of the samples suggested the development of an oxide scale in the outer regions that prevents its further bulk oxidation at temperatures above 500 °C, while below that temperature incomplete de-lubrication takes place.

  1. Osteoblast response to oxygen functionalised plasma polymer surfaces

    International Nuclear Information System (INIS)

    Kelly, Jonathan 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 copolymers was studied by enzyme linked immunosorbent assays and by I 125 radiolabelling. Fibronectin adsorbed in largest amounts to surfaces with intermediate concentrations of carboxyl functionality. Spreading of ROS cells and rat bone marrow stromal cells (BMSC) was characterised by computer image analysis. Cell spreading in media containing 10% serum, on a surface deposited from a plasma of 5 O/o acrylic acid was much greater than on the octadiene plasma polymer while most extensive cell spreading was observed on these surfaces when preadsorbed with fibronectin. Growth (proliferation) of BMSC was assessed over nine days and was found to be faster on an 50% acrylic acid plasma polymer than on tissue culture polystyrene or a hydrocarbon plasma polymer, though cell growth was fastest on fibronectin precoated substrates. Expression of cellular alkaline phosphatase, collagen and calcium reached similar levels on the 50% acrylic acid plasma polymer, tissue culture

  2. Osteoblast response to oxygen functionalised plasma polymer surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Jonathan M

    2001-07-01

    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 copolymers was studied by enzyme linked immunosorbent assays and by I{sup 125} radiolabelling. Fibronectin adsorbed in largest amounts to surfaces with intermediate concentrations of carboxyl functionality. Spreading of ROS cells and rat bone marrow stromal cells (BMSC) was characterised by computer image analysis. Cell spreading in media containing 10% serum, on a surface deposited from a plasma of 5 O/o acrylic acid was much greater than on the octadiene plasma polymer while most extensive cell spreading was observed on these surfaces when preadsorbed with fibronectin. Growth (proliferation) of BMSC was assessed over nine days and was found to be faster on an 50% acrylic acid plasma polymer than on tissue culture polystyrene or a hydrocarbon plasma polymer, though cell growth was fastest on fibronectin precoated substrates. Expression of cellular alkaline phosphatase, collagen and calcium reached similar levels on the 50% acrylic acid plasma polymer, tissue

  3. 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...

  4. 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

  5. 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

  6. 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...

  7. 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.

  8. An optimum design on rollers containing the groove with changeable inner diameter based on response surface methodology

    Directory of Open Access Journals (Sweden)

    Xi Zhao

    2016-05-01

    Full Text Available In order to realize the precision plastic forming of the revolving body component with changeable wall thickness, a kind of roller containing grooves with changeable inner diameter is put forward, as the forming mould of the technology of rolling-extrusion. Specifically, first, the arc length of the groove in the roller is designed according to the prediction on the forward slip value during the process of forming, to make accurate control of the actual length of the forming segments; then, to obtain better parameters of the roller structure, a second-order response surface model combining finite element numerical simulation and response surface methodology was put forward, taking the factor of forming uniformity as evaluation index. The result of the experiment shows that, for the formed component, not only the size can meet the needs but also each mechanical property index can be greatly improved, which verify the rationality of the forward slip model and the structural parameter of the optimum model based on the response surface methodology.

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

    DEFF Research Database (Denmark)

    Griskova, Inga; Mørup, Morten; Parnas, Josef

    2009-01-01

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

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. The absence of later wave components in auditory brainstem responses as an initial manifestation of type 2 Gaucher disease.

    Science.gov (United States)

    Okubo, Yusuke; Goto, Masahiro; Sakakibara, Hiroshi; Terakawa, Toshiro; Kaneko, Takashi; Miyama, Sahoko

    2014-12-01

    Type 2 Gaucher disease is the most severe neuronopathic form of Gaucher disease and is characterized by severe neurodegeneration with brainstem involvement and organ failure. Prediction or diagnosis of type 2 Gaucher disease before the development of neurological complications is difficult. A 5-month-old female infant presented with deafness without other neurological abnormalities. Auditory brainstem response analysis revealed the absence of later wave components. Two months later, muscular rigidity became evident, followed by the development of opisthotonus and strabismus. Rapid progression of splenomegaly led to the diagnosis of type 2 Gaucher disease. Abnormal auditory brainstem response findings may already exist before the development of severe brainstem abnormalities such as muscular rigidity and opisthotonus in type 2 Gaucher disease. When patients present with deafness and absent later wave components on auditory brainstem response, type 2 Gaucher disease should be included in the differential diagnosis even in the absence of other neurological abnormalities. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. 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)

  17. 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.

  18. 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)

  19. Surface characterization and cytotoxicity response of biodegradable magnesium alloys

    International Nuclear Information System (INIS)

    Pompa, Luis; Rahman, Zia Ur; Munoz, Edgar; Haider, Waseem

    2015-01-01

    Magnesium alloys have raised an immense amount of interest to many researchers because of their evolution as a new kind of third generation materials. Due to their biocompatibility, density, and mechanical properties, magnesium alloys are frequently reported as prospective biodegradable implant materials. Moreover, magnesium alloys experience a natural phenomenon to biodegrade in aqueous solutions due to its corrosion activity, which is excellent for orthopedic and cardiovascular applications. However, a major concern with such alloys is fast and non-uniform corrosion degradation. Controlling the degradation rate in the physiological environment determines the success of biodegradable implants. In this investigation, three different grades of magnesium alloys: AZ31B, AZ91E and ZK60A were studied for their corrosion resistance and biocompatibility. Scanning electron microscopy, energy dispersive spectroscopy, atomic force microscopy and contact angle meter are used to study surface morphology, chemistry, roughness and wettability, respectively. Additionally, the cytotoxicity of the leached metal ions was evaluated by using a tetrazolium based bio-assay, MTS. - Highlights: • Micro-textured features formed after the anodization of magnesium alloys. • Contact angle increased and surface free energy decreased by anodization. • Corrosion rate increased for anodized surfaces compared to untreated samples. • Cell viability was greater than 75% implying the cytocompatibility of Mg alloys

  20. Surface characterization and cytotoxicity response of biodegradable magnesium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Pompa, Luis; Rahman, Zia Ur; Munoz, Edgar; Haider, Waseem, E-mail: haiderw@utpa.edu

    2015-04-01

    Magnesium alloys have raised an immense amount of interest to many researchers because of their evolution as a new kind of third generation materials. Due to their biocompatibility, density, and mechanical properties, magnesium alloys are frequently reported as prospective biodegradable implant materials. Moreover, magnesium alloys experience a natural phenomenon to biodegrade in aqueous solutions due to its corrosion activity, which is excellent for orthopedic and cardiovascular applications. However, a major concern with such alloys is fast and non-uniform corrosion degradation. Controlling the degradation rate in the physiological environment determines the success of biodegradable implants. In this investigation, three different grades of magnesium alloys: AZ31B, AZ91E and ZK60A were studied for their corrosion resistance and biocompatibility. Scanning electron microscopy, energy dispersive spectroscopy, atomic force microscopy and contact angle meter are used to study surface morphology, chemistry, roughness and wettability, respectively. Additionally, the cytotoxicity of the leached metal ions was evaluated by using a tetrazolium based bio-assay, MTS. - Highlights: • Micro-textured features formed after the anodization of magnesium alloys. • Contact angle increased and surface free energy decreased by anodization. • Corrosion rate increased for anodized surfaces compared to untreated samples. • Cell viability was greater than 75% implying the cytocompatibility of Mg alloys.

  1. 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%.

  2. 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

  3. 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.

  4. 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 ...

  5. Lateralization and Binaural Interaction of Middle-Latency and Late-Brainstem Components of the Auditory Evoked Response.

    Science.gov (United States)

    Dykstra, Andrew R; Burchard, Daniel; Starzynski, Christian; Riedel, Helmut; Rupp, Andre; Gutschalk, Alexander

    2016-08-01

    We used magnetoencephalography to examine lateralization and binaural interaction of the middle-latency and late-brainstem components of the auditory evoked response (the MLR and SN10, respectively). Click stimuli were presented either monaurally, or binaurally with left- or right-leading interaural time differences (ITDs). While early MLR components, including the N19 and P30, were larger for monaural stimuli presented contralaterally (by approximately 30 and 36 % in the left and right hemispheres, respectively), later components, including the N40 and P50, were larger ipsilaterally. In contrast, MLRs elicited by binaural clicks with left- or right-leading ITDs did not differ. Depending on filter settings, weak binaural interaction could be observed as early as the P13 but was clearly much larger for later components, beginning at the P30, indicating some degree of binaural linearity up to early stages of cortical processing. The SN10, an obscure late-brainstem component, was observed consistently in individuals and showed linear binaural additivity. The results indicate that while the MLR is lateralized in response to monaural stimuli-and not ITDs-this lateralization reverses from primarily contralateral to primarily ipsilateral as early as 40 ms post stimulus and is never as large as that seen with fMRI.

  6. 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.

  7. Optical response of a flat metallic surface coated with a monolayer array of latex spheres

    International Nuclear Information System (INIS)

    Shi Lei; Liu Xiaohan; Yin Haiwei; Zi Jian

    2010-01-01

    We report on the fabrication, characterization and simulation of a structure consisting of a flat metallic surface coated with a monolayer array of latex spheres. This structure shows interesting optical response: over flat metallic surfaces a series of reflection minima appear in reflection spectra. Numerical simulations revealed that the structure can support two types of surface modes: surface plasmon-polaritons bound at the metallic surface and guided modes confined to the array of latex spheres, or their hybrids. Both experimental and theoretical results indicated that these surface modes show well-defined band structures due to the introduced periodicity by the monolayer array of latex spheres.

  8. 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.

  9. 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.

  10. Taking Teacher Responsibility into Account(ability): Explicating Its Multiple Components and Theoretical Status

    Science.gov (United States)

    Lauermann, Fani; Karabenick, Stuart A.

    2011-01-01

    Accountability systems have important implications for schooling. Missing from discussions about their implementation, however, are ways they affect teacher responsibility. Responsibility has been insufficiently explicated in the education literature, including its impact on teacher motivation, emotion, and behavior. We propose that a…

  11. 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.

  12. 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

  13. 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

  14. Monitoring of surface-fatigue crack propagation in a welded steel angle structure using guided waves and principal component analysis

    Science.gov (United States)

    Lu, Mingyu; Qu, Yongwei; Lu, Ye; Ye, Lin; Zhou, Limin; Su, Zhongqing

    2012-04-01

    An experimental study is reported in this paper demonstrating monitoring of surface-fatigue crack propagation in a welded steel angle structure using Lamb waves generated by an active piezoceramic transducer (PZT) network which was freely surface-mounted for each PZT transducer to serve as either actuator or sensor. The fatigue crack was initiated and propagated in welding zone of a steel angle structure by three-point bending fatigue tests. Instead of directly comparing changes between a series of specific signal segments such as S0 and A0 wave modes scattered from fatigue crack tips, a variety of signal statistical parameters representing five different structural status obtained from marginal spectrum in Hilbert-huang transform (HHT), indicating energy progressive distribution along time period in the frequency domain including all wave modes of one wave signal were employed to classify and distinguish different structural conditions due to fatigue crack initiation and propagation with the combination of using principal component analysis (PCA). Results show that PCA based on marginal spectrum is effective and sensitive for monitoring the growth of fatigue crack although the received signals are extremely complicated due to wave scattered from weld, multi-boundaries, notch and fatigue crack. More importantly, this method indicates good potential for identification of integrity status of complicated structures which cause uncertain wave patterns and ambiguous sensor network arrangement.

  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. 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.

  17. Triethylene glycol, an active component of Ashwagandha (Withania somnifera) leaves, is responsible for sleep induction.

    Science.gov (United States)

    Kaushik, Mahesh K; Kaul, Sunil C; Wadhwa, Renu; Yanagisawa, Masashi; Urade, Yoshihiro

    2017-01-01

    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.

  18. 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...

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

    Science.gov (United States)

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

    2006-01-01

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

  20. 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.

  1. Anode biofilm transcriptomics reveals outer surface components essential for high density current production in Geobacter sulfurreducens fuel cells.

    Directory of Open Access Journals (Sweden)

    Kelly P Nevin

    Full Text Available The mechanisms by which Geobacter sulfurreducens transfers electrons through relatively thick (>50 microm biofilms to electrodes acting as a sole electron acceptor were investigated. Biofilms of Geobacter sulfurreducens were grown either in flow-through systems with graphite anodes as the electron acceptor or on the same graphite surface, but with fumarate as the sole electron acceptor. Fumarate-grown biofilms were not immediately capable of significant current production, suggesting substantial physiological differences from current-producing biofilms. Microarray analysis revealed 13 genes in current-harvesting biofilms that had significantly higher transcript levels. The greatest increases were for pilA, the gene immediately downstream of pilA, and the genes for two outer c-type membrane cytochromes, OmcB and OmcZ. Down-regulated genes included the genes for the outer-membrane c-type cytochromes, OmcS and OmcT. Results of quantitative RT-PCR of gene transcript levels during biofilm growth were consistent with microarray results. OmcZ and the outer-surface c-type cytochrome, OmcE, were more abundant and OmcS was less abundant in current-harvesting cells. Strains in which pilA, the gene immediately downstream from pilA, omcB, omcS, omcE, or omcZ was deleted demonstrated that only deletion of pilA or omcZ severely inhibited current production and biofilm formation in current-harvesting mode. In contrast, these gene deletions had no impact on biofilm formation on graphite surfaces when fumarate served as the electron acceptor. These results suggest that biofilms grown harvesting current are specifically poised for electron transfer to electrodes and that, in addition to pili, OmcZ is a key component in electron transfer through differentiated G. sulfurreducens biofilms to electrodes.

  2. 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

  3. Calculating the sensitivity of wind turbine loads to wind inputs using response surfaces

    International Nuclear Information System (INIS)

    Rinker, Jennifer M.

    2016-01-01

    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 highdimensional polynomial surface that can be calibrated to any set of input/output data and then used to generate synthetic data 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 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. The fit of the calibrated response surface is evaluated in terms of error between the model and the training data and in terms of the convergence. The Sobol SIs are calculated using the calibrated response surface, and the convergence is examined. The Sobol SIs reveal that, of the four turbulence parameters examined in this paper, the variance caused by the Kaimal length scale and nonstationarity parameter are negligible. Thus, the findings in this paper represent the first systematic evidence that stochastic wind turbine load response statistics can be modeled purely by mean wind wind speed and turbulence intensity. (paper)

  4. 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.

  5. Modification of surface/neuron interfaces for neural cell-type specific responses: a review

    International Nuclear Information System (INIS)

    Chen, Cen; Kong, Xiangdong; Lee, In-Seop

    2016-01-01

    Surface/neuron interfaces have played an important role in neural repair including neural prostheses and tissue engineered scaffolds. This comprehensive literature review covers recent studies on the modification of surface/neuron interfaces. These interfaces are identified in cases both where the surfaces of substrates or scaffolds were in direct contact with cells and where the surfaces were modified to facilitate cell adhesion and controlling cell-type specific responses. Different sources of cells for neural repair are described, such as pheochromocytoma neuronal-like cell, neural stem cell (NSC), embryonic stem cell (ESC), mesenchymal stem cell (MSC) and induced pluripotent stem cell (iPS). Commonly modified methods are discussed including patterned surfaces at micro- or nano-scale, surface modification with conducting coatings, and functionalized surfaces with immobilized bioactive molecules. These approaches to control cell-type specific responses have enormous potential implications in neural repair. (paper)

  6. 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...

  7. 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

  8. 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

  9. 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.

  10. Artificial hairy surfaces with a nearly perfect hydrophobic response.

    Science.gov (United States)

    Hsu, Shu-Hau; Sigmund, Wolfgang M

    2010-02-02

    A nearly perfect hydrophobic interface by dint of mimicking hairs of arthropods was achieved for the first time. These Gamma-shape artificial hairs were made via a membrane casting technique on polypropylene substrates. This extreme hydrophobicity merely arises from microstructure modification, and no further chemical treatments are needed. The ultralow adhesion to water droplets was evaluated through video assessment, and it is believed to be attributed to the mechanical response of the artificial hairs. The principle of this fabrication technique is accessible and is expected to be compatible with large-area fabrication of superhydrophobic interfaces.

  11. Water response to ganglioside GM1 surface remodelling.

    Science.gov (United States)

    Brocca, P; Rondelli, V; Mallamace, F; Di Bari, M T; Deriu, A; Lohstroh, W; Del Favero, E; Corti, M; Cantu', L

    2017-01-01

    Gangliosides are biological glycolipids participating in rafts, structural and functional domains of cell membranes. Their headgroups are able to assume different conformations when packed on the surface of an aggregate, more lying or standing. Switching between different conformations is possible, and is a collective event. Switching can be induced, in model systems, by concentration or temperature increase, then possibly involving ganglioside-water interaction. In the present paper, the effect of GM1 ganglioside headgroup conformation on the water structuring and interactions is addressed. Depolarized Rayleigh Scattering, Raman Scattering, Quasielastic Neutron Scattering and NMR measurements were performed on GM1 ganglioside solutions, focusing on solvent properties. All used techniques agree in evidencing differences in the structure and dynamics of solvent water on different time-and-length scales in the presence of either GM1 headgroup conformations. In general, all results indicate that both the structural properties of solvent water and its interactions with the sugar headgroups of GM1 respond to surface remodelling. The extent of this modification is much higher than expected and, interestingly, ganglioside headgroups seem to turn from cosmotropes to chaotropes upon collective rearrangement from the standing- to the lying-conformation. In a biological perspective, water structure modulation could be one of the physico-chemical elements contributing to the raft strategy, both for rafts formation and persistence and for their functional aspects. In particular, the interaction with approaching bodies could be favoured or inhibited or triggered by complex-sugar-sequence conformational switch. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. 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.

  13. A first principle simulation of competitive adsorption of SF6 decomposition components on nitrogen-doped anatase TiO2 (101) surface

    Science.gov (United States)

    Dong, Xingchen; Zhang, Xiaoxing; Cui, Hao; Zhang, Jun

    2017-11-01

    Gas insulated switchgear has been widely used in modern electric systems due to its significantly excellent performances such as compact structure and low land occupation as well as the security stability. However, inside defects caused during manufacture process can lead to partial discharge which might develop into serious insulation failure. Online monitoring method on basis of gas sensors is considered a promising way of detecting partial discharge for alarm ahead of time. Research has found that TiO2 nanotubes sensors show good response to SO2, SOF2, SO2F2, the decomposition components as a result of partial discharge. In order to investigate the gas-sensing mechanism of nitrogen-doped TiO2 prepared via plasma treatment methods to SO2, SOF2, and SO2F2, the adsorption structures of both three gas molecules and anatase TiO2 (101) surface were built, and DFT calculations were then carried out for calculation and analysis of adsorption parameters. Adsorption property comparison of anatase TiO2 (101) surface after nitrogen doping with Au doping and without doping shows that nitrogen doping can obviously enhance the adsorption energy for SO2 and SOF2 adsorption and no charge transfer for SO2F2 adsorption, further explaining the adsorption mechanism and doping influence of different doping elements.

  14. 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.

  15. Monte Carlo simulation of the scattered component of neutron capture prompt gamma-ray analyzer responses

    International Nuclear Information System (INIS)

    Jin, Y.; Verghese, K.; Gardner, R.P.

    1986-01-01

    This paper describes a major part of our efforts to simulate the entire spectral response of the neutron capture prompt gamma-ray analyzer for bulk media (or conveyor belt) samples by the Monte Carlo method. This would allow one to use such a model to augment or, in most cases, essentially replace experiments in the calibration and optimum design of these analyzers. In previous work, we simulated the unscattered gamma-ray intensities, but would like to simulate the entire spectral response as we did with the energy-dispersive x-ray fluorescence analyzers. To accomplish this, one must account for the scattered gamma rays as well as the unscattered and one must have available the detector response function to translate the incident gamma-ray spectrum calculated by the Monte Carlo simulation into the detected pulse-height spectrum. We recently completed our work on the germanium detector response function, and the present paper describes our efforts to simulate the entire spectral response by using it with Monte Carlo predicted unscattered and scattered gamma rays

  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. 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.

  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. 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

  20. A thermal lens response of the two components liquid in a thin Him cell

    International Nuclear Information System (INIS)

    Ivanov, V I; Ivanova, G D

    2016-01-01

    It was proposed a new thermal lens scheme with a thin layer of cell thickness which is significantly less than the size of the beam. As a result the exact analytical expression for the thermal lens response is achieved, taking into account the thermal lens in the windows of the cell. (paper)

  1. 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.

  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

    International Nuclear Information System (INIS)

    Chinnadurai, T.; Vendan, S.A.

    2016-01-01

    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. 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)

  5. Pharmacogenetic landscape of Metabolic Syndrome components drug response in Tunisia and comparison with worldwide populations.

    Science.gov (United States)

    Jmel, Haifa; Romdhane, Lilia; Ben Halima, Yosra; Hechmi, Meriem; Naouali, Chokri; Dallali, Hamza; Hamdi, Yosr; Shan, Jingxuan; Abid, Abdelmajid; Jamoussi, Henda; Trabelsi, Sameh; Chouchane, Lotfi; Luiselli, Donata; Abdelhak, Sonia; Kefi, Rym

    2018-01-01

    Genetic variation is an important determinant affecting either drug response or susceptibility to adverse drug reactions. Several studies have highlighted the importance of ethnicity in influencing drug response variability that should be considered during drug development. Our objective is to characterize the genetic variability of some pharmacogenes involved in the response to drugs used for the treatment of Metabolic Syndrome (MetS) in Tunisia and to compare our results to the worldwide populations. A set of 135 Tunisians was genotyped using the Affymetrix Chip 6.0 genotyping array. Variants located in 24 Very Important Pharmacogenes (VIP) involved in MetS drug response were extracted from the genotyping data. Analysis of variant distribution in Tunisian population compared to 20 worldwide populations publicly available was performed using R software packages. Common variants between Tunisians and the 20 investigated populations were extracted from genotyping data. Multidimensional screening showed that Tunisian population is clustered with North African and European populations. The greatest divergence was observed with the African and Asian population. In addition, we performed Inter-ethnic comparison based on the genotype frequencies of five VIP biomarkers. The genotype frequencies of the biomarkers rs3846662, rs1045642, rs7294 and rs12255372 located respectively in HMGCR, ABCB1, VKORC1 and TCF7L2 are similar between Tunisian, Tuscan (TSI) and European (CEU). The genotype frequency of the variant rs776746 located in CYP3A5 gene is similar between Tunisian and African populations and different from CEU and TSI. The present study shows that the genetic make up of the Tunisian population is relatively complex in regard to pharmacogenes and reflects previous historical events. It is important to consider this ethnic difference in drug prescription in order to optimize drug response to avoid serious adverse drug reactions. Taking into account similarities with

  6. Pharmacogenetic landscape of Metabolic Syndrome components drug response in Tunisia and comparison with worldwide populations

    Science.gov (United States)

    Jmel, Haifa; Romdhane, Lilia; Ben Halima, Yosra; Hechmi, Meriem; Naouali, Chokri; Dallali, Hamza; Hamdi, Yosr; Shan, Jingxuan; Abid, Abdelmajid; Jamoussi, Henda; Trabelsi, Sameh; Chouchane, Lotfi; Luiselli, Donata; Abdelhak, Sonia

    2018-01-01

    Genetic variation is an important determinant affecting either drug response or susceptibility to adverse drug reactions. Several studies have highlighted the importance of ethnicity in influencing drug response variability that should be considered during drug development. Our objective is to characterize the genetic variability of some pharmacogenes involved in the response to drugs used for the treatment of Metabolic Syndrome (MetS) in Tunisia and to compare our results to the worldwide populations. A set of 135 Tunisians was genotyped using the Affymetrix Chip 6.0 genotyping array. Variants located in 24 Very Important Pharmacogenes (VIP) involved in MetS drug response were extracted from the genotyping data. Analysis of variant distribution in Tunisian population compared to 20 worldwide populations publicly available was performed using R software packages. Common variants between Tunisians and the 20 investigated populations were extracted from genotyping data. Multidimensional screening showed that Tunisian population is clustered with North African and European populations. The greatest divergence was observed with the African and Asian population. In addition, we performed Inter-ethnic comparison based on the genotype frequencies of five VIP biomarkers. The genotype frequencies of the biomarkers rs3846662, rs1045642, rs7294 and rs12255372 located respectively in HMGCR, ABCB1, VKORC1 and TCF7L2 are similar between Tunisian, Tuscan (TSI) and European (CEU). The genotype frequency of the variant rs776746 located in CYP3A5 gene is similar between Tunisian and African populations and different from CEU and TSI. The present study shows that the genetic make up of the Tunisian population is relatively complex in regard to pharmacogenes and reflects previous historical events. It is important to consider this ethnic difference in drug prescription in order to optimize drug response to avoid serious adverse drug reactions. Taking into account similarities with

  7. Reliability Evaluation of Bridges Based on Nonprobabilistic Response Surface Limit Method

    OpenAIRE

    Chen, Xuyong; Chen, Qian; Bian, Xiaoya; Fan, Jianping

    2017-01-01

    Due to many uncertainties in nonprobabilistic reliability assessment of bridges, the limit state function is generally unknown. The traditional nonprobabilistic response surface method is a lengthy and oscillating iteration process and leads to difficultly solving the nonprobabilistic reliability index. This article proposes a nonprobabilistic response surface limit method based on the interval model. The intention of this method is to solve the upper and lower limits of the nonprobabilistic ...

  8. 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.

  9. 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.

  10. Relationship between oxygen uptake slow component and surface EMG during heavy exercise in humans: influence of pedal rate.

    Science.gov (United States)

    Vercruyssen, Fabrice; Missenard, Olivier; Brisswalter, Jeanick

    2009-08-01

    The aim of this study was to test the hypothesis that extreme pedal rates contributed to the slow component of oxygen uptake (VO(2) SC) in association with changes in surface electromyographic (sEMG) during heavy-cycle exercise. Eight male trained cyclists performed two square-wave transitions at 50 and 110 rpm at a work rate that would elicit a VO(2) corresponding to 50% of the difference between peak VO(2) and the ventilatory threshold. Pulmonary gas exchange was measured breath-by-breath and sEMG was obtained from the vastus lateralis and medialis muscles. Integrated EMG flow (QiEMG) and mean power frequency (MPF) were computed. The relative amplitude of the VO(2) SC was significantly higher during the 110-rpm bout (556+/-186 ml min(-1), Pexercise only during the 110-rpm bout and were associated with the greater amplitude of the VO(2) SC observed for this condition (Pmotor units recruitment pattern, muscle energy turnover and muscle temperature have been suggested to explain the different VO(2) SC to heavy pedal rate bouts.

  11. Optimization of Extraction Parameters of Phenolic Compounds from Sarcopoterium spinosum Leaves by Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Ceren Sunguc

    2017-07-01

    Full Text Available The shrublands are very common in Urla-Çeşme-Karaburun peninsula located in the western point of Turkey. Prickly shrubby burnet (Sarcopoterium spinosum L. is one of the common weed which has intensive thorns making its consumption for the local domestic animals. However, Sarcopoterium spinosum is a valuable and common medicinal plant in the Mediterranean region. Crude extract of S. spinosum leaves exhibited higher antioxidant activity, as 3143.5± 238.5 µM TEAC (Trolox Equivalent Antioxidant Capacity/g dry weight (DW, when compared to other medicinal plants found in the literature. The aim of this study was to determine the effect of extraction parameters on the content and biological activity of the extract by response surface methodology (RSM as well as to identify its major compounds. High Performance Liquid Chromatography (HPLC was employed to investigate the phenolic content of S. spinosum extract. The composition of the phenolic contents including hyperoside and isoquercetin, the latter being the major component, in S. spinosum extract has been shown for the first time by HPLC. Antimicrobial activity of S. spinosum extract, identified by minimum inhibition concentration (MIC assay, indicated that the crude extract had antifungal activity against Candida albicans.

  12. 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.

  13. 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.

  14. 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.

  15. Optimization of a natural medium for cellulase by a marine Aspergillus niger using response surface methodology.

    Science.gov (United States)

    Xue, Dong-Sheng; Chen, Hui-Yin; Lin, Dong-Qiang; Guan, Yi-Xin; Yao, Shan-Jing

    2012-08-01

    The components of a natural medium were optimized to produce cellulase from a marine Aspergillus niger under solid state fermentation conditions by response surface methodology. Eichhornia crassipes and natural seawater were used as a major substrate and a source of mineral salts, respectively. Mineral salts of natural seawater could increase cellulase production. Raw corn cob and raw rice straw showed a significant positive effect on cellulase production. The optimum natural medium consisted of 76.9 % E. crassipes (w/w), 8.9 % raw corn cob (w/w), 3.5 % raw rice straw (w/w), 10.7 % raw wheat bran (w/w), and natural seawater (2.33 times the weight of the dry substrates). Incubation for 96 h in the natural medium increased the biomass to the maximum. The cellulase production was 17.80 U/g the dry weight of substrates after incubation for 144 h. The natural medium avoided supplying chemicals and pretreating substrates. It is promising for future practical fermentation of environment-friendly producing cellulase.

  16. Influence of Drilling Parameters on Torque during Drilling of GFRP Composites Using Response Surface Methodology

    Science.gov (United States)

    Mohan, N. S.; Kulkarni, S. M.

    2018-01-01

    Polymer based composites have marked their valuable presence in the area of aerospace, defense and automotive industry. Components made of composite, are assembled to main structure by fastener, which require accurate, precise high quality holes to be drilled. Drilling the hole in composite with accuracy require control over various processes parameters viz., speed, feed, drill bit size and thickens of specimen. TRIAC VMC machining center is used to drill the hole and to relate the cutting and machining parameters on the torque. MINITAB 14 software is used to analyze the collected data. As a function of cutting and specimen parameters this method could be useful for predicting torque parameters. The purpose of this work is to investigate the effect of drilling parameters to get low torque value. Results show that thickness of specimen and drill bit size are significant parameters influencing the torque and spindle speed and feed rate have least influence and overlaid plot indicates a feasible and low region of torque is observed for medium to large sized drill bits for the range of spindle speed selected. Response surface contour plots indicate the sensitivity of the drill size and specimen thickness to the torque.

  17. 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.

  18. Female responses to experimental removal of sexual selection components in Drosophila melanogaster

    OpenAIRE

    Innocenti, Paolo; Flis, Ilona; Morrow, Edward H.

    2014-01-01

    Background Despite the common assumption that multiple mating should in general be favored in males, but not in females, to date there is no consensus on the general impact of multiple mating on female fitness. Notably, very little is known about the genetic and physiological features underlying the female response to sexual selection pressures. By combining an experimental evolution approach with genomic techniques, we investigated the effects of single and multiple matings on female fecundi...

  19. 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......Resistance arises quickly during chemotherapeutic selection and is particularly problematic during long-term treatment regimens such as those for tuberculosis, HIV infections, or cancer. Although drug combination therapy reduces the evolution of drug resistance, drug pairs vary in their ability...

  20. 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.

  1. 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.

  2. 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.

  3. Tip-surface interactions at redox responsive poly(ferrocenylsilane) (PFS) interface by AFM-based force spectroscopy

    International Nuclear Information System (INIS)

    Chung Hongjing; Song Jing; Vancso, G. Julius

    2009-01-01

    Poly(ferrocenylsilanes) (PFS) belong to the class of redox responsive organometallic polymers. Atomic force microscopy (AFM)-based single molecule force spectroscopy (SMFS) was used earlier to study single chain PFS response and redox energy driven single chain PFS molecular motors. Here we present further AFM investigations of force interactions between tip and a grafted PFS surface under potential control in electrochemical redox cycles. Typical tip-Au interaction is considered as reference in the force measurements. First the electrostatic component in the diffused double layer (DL) in NaClO 4 electrolyte environment was considered for a 'grafted to' PFS, which dominated the interplay between the tip and sample surface. The DL forces can also hinder the physisorption of PFS chain onto the tip when the voltage was applied at -0.1 V. On the other hand, if the tip contacted the PFS surface prior to the electrochemical process, physisorption of PFS chains governed the overall interaction regardless of subsequently applied surface potential. In addition, prolonged contact time, t c , may also contribute to the stability of tip-PFS bridging and detection of electrostatic forces between the tip-PFS interface. The results showed that tip-substrate interaction forces without PFS grafts have negligibly small force contributions under similar, electrochemically controlled, conditions used in single PFS chain based molecular motors.

  4. An effective vacuum assisted extraction method for the optimization of labdane diterpenoids from Andrographis paniculata by response surface methodology.

    Science.gov (United States)

    Wang, Ya-Qi; Wu, Zhen-Feng; Ke, Gang; Yang, Ming

    2014-12-31

    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.

  5. 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.

  6. Optimization of the Medium for the Production of Cellulase by the Mutant Trichoderma reesei WX-112 Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Xue-Cai Hao

    2006-01-01

    Full Text Available The mutant strain Trichoderma reesei WX-112 with high cellulase activity was isolated by a newly invented plate. The mutant’s ability to produce cellulase increased 1.95 times after the treatment with UV and N-methyl-N’-nitro-N-nitrosoguanidine (MNNG. Also, the medium composition was optimized using response surface methodology (RSM. A fractional factorial design (26–2 was applied to elucidate the medium components that significantly affect cellulase production. The concentration of Avicel and soybean cake flour in the medium were significant factors. The steepest ascent method was used to locate the optimal domain and a central composite design was used to estimate the quadratic response surface from which the factor levels for maximum production of cellulase were determined. The composition of fermentation medium optimized with response surface methodology was (in g/L: wheat bran 30, Avicel 36.4, soybean cake flour 24.7, KH2PO4 4 and corn steep flour 5. Compared to the original medium, the cellulase activity increased from 7.2 to 10.6 IU/mL.

  7. An Intelligent Method for Structural Reliability Analysis Based on Response Surface

    Institute of Scientific and Technical Information of China (English)

    桂劲松; 刘红; 康海贵

    2004-01-01

    As water depth increases, the structural safety and reliability of a system become more and more important and challenging. Therefore, the structural reliability method must be applied in ocean engineering design such as offshore platform design. If the performance function is known in structural reliability analysis, the first-order second-moment method is often used. If the performance function could not be definitely expressed, the response surface method is always used because it has a very clear train of thought and simple programming. However, the traditional response surface method fits the response surface of quadratic polynomials where the problem of accuracy could not be solved, because the true limit state surface can be fitted well only in the area near the checking point. In this paper, an intelligent computing method based on the whole response surface is proposed, which can be used for the situation where the performance function could not be definitely expressed in structural reliability analysis. In this method, a response surface of the fuzzy neural network for the whole area should be constructed first, and then the structural reliability can be calculated by the genetic algorithm. In the proposed method, all the sample points for the training network come from the whole area, so the true limit state surface in the whole area can be fitted. Through calculational examples and comparative analysis, it can be known that the proposed method is much better than the traditional response surface method of quadratic polynomials, because, the amount of calculation of finite element analysis is largely reduced, the accuracy of calculation is improved,and the true limit state surface can be fitted very well in the whole area. So, the method proposed in this paper is suitable for engineering application.

  8. 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.

  9. 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.)

  10. Why energy from waste incineration is an essential component of environmentally responsible waste management

    International Nuclear Information System (INIS)

    Porteous, A.

    2005-01-01

    This paper outlines the key factors involved in adopting energy from waste incineration (EfWI) as part of a waste management strategy. Incineration means all forms of controlled direct combustion of waste. 'Emerging' technologies, such as gasification, are, in the author's view, 5 to 10 years from proven commercial application. The strict combustion regimen employed and the emissions therefrom are detailed. It is shown that EfWI merits consideration as an integral part of an environmentally responsible and sustainable waste management strategy, where suitable quantities of waste are available

  11. 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.

  12. 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.

  13. 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).

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. Optimization of CO2 Laser Cutting Process using Taguchi and Dual Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    M. Madić

    2014-09-01

    Full Text Available Selection of optimal cutting parameter settings for obtaining high cut quality in CO2 laser cutting process is of great importance. Among various analytical and experimental optimization methods, the application of Taguchi and response surface methodology is one of most commonly used for laser cutting process optimization. Although the concept of dual response surface methodology for process optimization has been used with success, till date, no experimental study has been reported in the field of laser cutting. In this paper an approach for optimization of CO2 laser cutting process using Taguchi and dual response surface methodology is presented. The goal was to determine the near optimal laser cutting parameter values in order to ensure robust condition for minimization of average surface roughness. To obtain experimental database for development of response surface models, Taguchi’s L25 orthogonal array was implemented for experimental plan. Three cutting parameters, the cutting speed (3, 4, 5, 6, 7 m/min, the laser power (0.7, 0.9, 1.1, 1.3, 1.5 kW, and the assist gas pressure (3, 4, 5, 6, 7 bar, were used in the experiment. To obtain near optimal cutting parameters settings, multi-stage Monte Carlo simulation procedure was performed on the developed response surface models.

  19. Effect of Q-switched Laser Surface Texturing of Titanium on Osteoblast Cell Response

    Science.gov (United States)

    Voisey, K. T.; Scotchford, C. A.; Martin, L.; Gill, H. S.

    Titanium and its alloys are important biomedical materials. It is known that the surface texture of implanted medical devices affects cell response. Control of cell response has the potential to enhance fixation of implants into bone and, in other applications, to prevent undesired cell adhesion. The potential use of a 100W Q-switched YAG laser miller (DMG Lasertec 60 HSC) for texturing titanium is investigated. A series of regular features with dimensions of the order of tens of micrometers are generated in the surface of titanium samples and the cell response to these features is determined. Characterisation of the laser milled features reveals features with a lengthscale of a few microns superposed on the larger scale structures, this is attributed to resolidification of molten droplets generated and propelled over the surface by individual laser pulses. The laser textured samples are exposed to osteoblast cells and it is seen that cells do respond to the features in the laser textured surfaces.

  20. Using the Vertical Component of the Surface Velocity Field to Map the Locked Zone at Cascadia Subduction Zone

    Science.gov (United States)

    Moulas, E.; Brandon, M. T.; Podladchikov, Y.; Bennett, R. A.

    2014-12-01

    At present, our understanding of the locked zone at Cascadia subduction zone is based on thermal modeling and elastic modeling of horizontal GPS velocities. The thermal model by Hyndman and Wang (1995) provided a first-order assessment of where the subduction thrust might be cold enough for stick-slip behavior. The alternative approach by McCaffrey et al. (2007) is to use a Green's function that relates horizontal surface velocities, as recorded by GPS, to interseismic elastic deformation. The thermal modeling approach is limited by a lack of information about the amount of frictional heating occurring on the thrust (Molnar and England, 1990). The GPS approach is limited in that the horizontal velocity component is fairly insensitive to the structure of the locked zone. The vertical velocity component is much more useful for this purpose. We are fortunate in that vertical velocities can now be measured by GPS to a precision of about 0.2 mm/a. The dislocation model predicts that vertical velocities should range up to about 20 percent of the subduction velocity, which means maximum values of ~7 mm/a. The locked zone is generally entirely offshore at Cascadia, except for the Olympic Peninsula region, where the underlying Juan De Fuca plate has an anomalously low dip. Previous thermal and GPS modeling, as well as tide gauge data and episodic tremors indicate the locked zone there extends about 50 to 75 km onland. This situation provides an opportunity to directly study the locked zone. With that objective in mind, we have constructed a full 3D geodynamic model of the Cascadia subduction zone. At present, the model provides a full representation of the interseismic elastic deformation due to variations of slip on the subduction thrust. The model has been benchmarked against the Savage (2D) and Okada (3D) analytical solutions. This model has an important advantage over traditional dislocation modeling in that we include temperature-sensitive viscosity for the upper and

  1. An analytical solution to calculate bulk mole fractions for any number of components in aerosol droplets after considering partitioning to a surface layer

    Directory of Open Access Journals (Sweden)

    D. Topping

    2010-11-01

    Full Text Available Calculating the equilibrium composition of atmospheric aerosol particles, using all variations of Köhler theory, has largely assumed that the total solute concentrations define both the water activity and surface tension. Recently however, bulk to surface phase partitioning has been postulated as a process which significantly alters the predicted point of activation. In this paper, an analytical solution to calculate the removal of material from a bulk to a surface layer in aerosol particles has been derived using a well established and validated surface tension framework. The applicability to an unlimited number of components is possible via reliance on data from each binary system. Whilst assumptions regarding behaviour at the surface layer have been made to facilitate derivation, it is proposed that the framework presented can capture the overall impact of bulk-surface partitioning. Demonstrations of the equations for two and five component mixtures are given while comparisons are made with more detailed frameworks capable at modelling ternary systems at higher levels of complexity. Predictions made by the model across a range of surface active properties should be tested against measurements. Indeed, reccomendations are given for experimental validation and to assess sensitivities to accuracy and required level of complexity within large scale frameworks. Importantly, the computational efficiency of using the solution presented in this paper is roughly a factor of 20 less than a similar iterative approach, a comparison with highly coupled approaches not available beyond a 3 component system.

  2. 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.

  3. 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

  4. 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

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. Potential Response to Selection of HSP70 as a Component of Innate Immunity in the Abalone Haliotis rufescens

    Science.gov (United States)

    Brokordt, Katherina B.; González, Roxana C.; Farías, William J.; Winkler, Federico M.

    2015-01-01

    Assessing components of the immune system may reflect disease resistance. In some invertebrates, heat shock proteins (HSPs) are immune effectors and have been described as potent activators of the innate immune response. Several diseases have become a threat to abalone farming worldwide; therefore, increasing disease resistance is considered to be a long-term goal for breeding programs. A trait will respond to selection only if it is determined partially by additive genetic variation. The aim of this study was to estimate the heritability (h 2) and the additive genetic coefficient of variation (CV A) of HSP70 as a component of innate immunity of the abalone Haliotis rufescens, in order to assess its potential response to selection. These genetic components were estimated for the variations in the intracellular (in haemocytes) and extracellular (serum) protein levels of HSP70 in response to an immunostimulant agent in 60 full-sib families of H. rufescens. Levels of HSP70 were measured twice in the same individuals, first when they were young and again when they were pre-harvest adults, to estimate the repeatability (R), the h 2 and the potential response to selection of these traits at these life stages. High HSP70 levels were observed in abalones subjected to immunostimulation in both the intracellular and extracellular haemolymph fractions. This is the first time that changes in serum levels of HSP70 have been reported in response to an immune challenge in molluscs. HSP70 levels in both fractions and at both ages showed low h 2 and R, with values that were not significantly different from zero. However, HSP70 induced levels had a CV A of 13.3–16.2% in young adults and of 2.7–8.1% in pre-harvest adults. Thus, despite its low h 2, HSP70 synthesis in response to an immune challenge in red abalone has the potential to evolve through selection because of its large phenotypic variation and the presence of additive genetic variance, especially in young animals. PMID

  11. Potential Response to Selection of HSP70 as a Component of Innate Immunity in the Abalone Haliotis rufescens.

    Directory of Open Access Journals (Sweden)

    Katherina B Brokordt

    Full Text Available Assessing components of the immune system may reflect disease resistance. In some invertebrates, heat shock proteins (HSPs are immune effectors and have been described as potent activators of the innate immune response. Several diseases have become a threat to abalone farming worldwide; therefore, increasing disease resistance is considered to be a long-term goal for breeding programs. A trait will respond to selection only if it is determined partially by additive genetic variation. The aim of this study was to estimate the heritability (h2 and the additive genetic coefficient of variation (CVA of HSP70 as a component of innate immunity of the abalone Haliotis rufescens, in order to assess its potential response to selection. These genetic components were estimated for the variations in the intracellular (in haemocytes and extracellular (serum protein levels of HSP70 in response to an immunostimulant agent in 60 full-sib families of H. rufescens. Levels of HSP70 were measured twice in the same individuals, first when they were young and again when they were pre-harvest adults, to estimate the repeatability (R, the h2 and the potential response to selection of these traits at these life stages. High HSP70 levels were observed in abalones subjected to immunostimulation in both the intracellular and extracellular haemolymph fractions. This is the first time that changes in serum levels of HSP70 have been reported in response to an immune challenge in molluscs. HSP70 levels in both fractions and at both ages showed low h2 and R, with values that were not significantly different from zero. However, HSP70 induced levels had a CVA of 13.3-16.2% in young adults and of 2.7-8.1% in pre-harvest adults. Thus, despite its low h2, HSP70 synthesis in response to an immune challenge in red abalone has the potential to evolve through selection because of its large phenotypic variation and the presence of additive genetic variance, especially in young animals.

  12. 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.

  13. Direct and indirect selection responses for seed yield and its components in

    Directory of Open Access Journals (Sweden)

    rasoul dehghan

    2017-06-01

    Full Text Available Breeding based on selection indices is an effective method for improving complex traits such as yield. To assess the efficiency of different selection method, 83 exotic along with 17 Iranian safflower genotypes were evaluated at the research farm of Isfahan University of Technology using 10×10 simple lattice design with three replications in 2011. In this study, the selection indices of Smith-Hazel and Pesek-Baker were determined based on the number of capitulum per plant, number of seeds per capitulum and 1000-seed weight. Also response to selection and relative selection efficiency were estimated for traits under study and seed yield. The highest estimated selection efficiency for genetic improvement of seed yield was obtained via selection for number of capitulum per plant. Therefore, this trait can be used as an appropriate selection criterion for improvement of seed yield. The results showed that seed yield was highly correlated with each of these indices and the estimated efficiency of indirect selection via these indices was relatively high. Thus, it seems that these selection indices can be effectively used for seed yield improvement. Results of present study showed that the efficiency of Smith-Hazel indices for simultaneous improvement of number of capitulum per plant, number of seeds per capitulum and 1000-seed weight was higher than that of Pesek-Baker index.

  14. Occidiofungin is an important component responsible for the antifungal activity of Burkholderia pyrrocinia strain Lyc2.

    Science.gov (United States)

    Wang, X Q; Liu, A X; Guerrero, A; Liu, J; Yu, X Q; Deng, P; Ma, L; Baird, S M; Smith, L; Li, X D; Lu, S E

    2016-03-01

    To identify the taxonomy of tobacco rhizosphere-isolated strain Lyc2 and investigate the mechanisms of the antifungal activities, focusing on antimicrobials gene clusters identification and function analysis. Multilocus sequence typing and 16S rRNA analyses indicated that strain Lyc2 belongs to Burkholderia pyrrocinia. Bioassay results indicated strain Lyc2 showed significant antifungal activities against a broad range of plant and animal fungal pathogens and control efficacy on seedling damping off disease of cotton. A 55·2-kb gene cluster which was homologous to ocf gene clusters in Burkholderia contaminans MS14 was confirmed to be responsible for antifungal activities by random mutagenesis; HPLC was used to verify the production of antifungal compounds. Multiple antibiotic and secondary metabolized biosynthesis gene clusters predicated by antiSMASH revealed the broad spectrum of antimicrobials activities of the strain. Our results revealed the mechanisms of antifungal activities of strain Lyc2 and expand our knowledge about production of occidiofungin in the bacteria Burkholderia. Understanding the mechanisms of antifungal activities of strain Lyc2 has contributed to discovery of new antibiotics and expand our knowledge of production of occidiofungin in the bacteria Burkholderia. © 2015 The Society for Applied Microbiology.

  15. 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)

  16. UV laser-ablated surface textures as potential regulator of cellular response.

    Science.gov (United States)

    Chandra, Prafulla; Lai, Karen; Sung, Hak-Joon; Murthy, N Sanjeeva; Kohn, Joachim

    2010-06-01

    Textured surfaces obtained by UV laser ablation of poly(ethylene terephthalate) films were used to study the effect of shape and spacing of surface features on cellular response. Two distinct patterns, cones and ripples with spacing from 2 to 25 μm, were produced. Surface features with different shapes and spacings were produced by varying pulse repetition rate, laser fluence, and exposure time. The effects of the surface texture parameters, i.e., shape and spacing, on cell attachment, proliferation, and morphology of neonatal human dermal fibroblasts and mouse fibroblasts were studied. Cell attachment was the highest in the regions with cones at ∼4 μm spacing. As feature spacing increased, cell spreading decreased, and the fibroblasts became more circular, indicating a stress-mediated cell shrinkage. This study shows that UV laser ablation is a useful alternative to lithographic techniques to produce surface patterns for controlling cell attachment and growth on biomaterial surfaces.

  17. 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.

  18. An optimal design of wind turbine and ship structure based on neuro-response surface method

    Directory of Open Access Journals (Sweden)

    Jae-Chul Lee

    2015-07-01

    Full Text Available The geometry of engineering systems affects their performances. For this reason, the shape of engineering systems needs to be optimized in the initial design stage. However, engineering system design problems consist of multi-objective optimization and the performance analysis using commercial code or numerical analysis is generally time-consuming. To solve these problems, many engineers perform the optimization using the approximation model (response surface. The Response Surface Method (RSM is generally used to predict the system performance in engi-neering research field, but RSM presents some prediction errors for highly nonlinear systems. The major objective of this research is to establish an optimal design method for multi-objective problems and confirm its applicability. The proposed process is composed of three parts: definition of geometry, generation of response surface, and optimization process. To reduce the time for performance analysis and minimize the prediction errors, the approximation model is generated using the Backpropagation Artificial Neural Network (BPANN which is considered as Neuro-Response Surface Method (NRSM. The optimization is done for the generated response surface by non-dominated sorting genetic algorithm-II (NSGA-II. Through case studies of marine system and ship structure (substructure of floating offshore wind turbine considering hydrodynamics performances and bulk carrier bottom stiffened panels considering structure performance, we have confirmed the applicability of the proposed method for multi-objective side constraint optimization problems.

  19. An optimal design of wind turbine and ship structure based on neuro-response surface method

    Science.gov (United States)

    Lee, Jae-Chul; Shin, Sung-Chul; Kim, Soo-Young

    2015-07-01

    The geometry of engineering systems affects their performances. For this reason, the shape of engineering systems needs to be optimized in the initial design stage. However, engineering system design problems consist of multi-objective optimization and the performance analysis using commercial code or numerical analysis is generally time-consuming. To solve these problems, many engineers perform the optimization using the approximation model (response surface). The Response Surface Method (RSM) is generally used to predict the system performance in engineering research field, but RSM presents some prediction errors for highly nonlinear systems. The major objective of this research is to establish an optimal design method for multi-objective problems and confirm its applicability. The proposed process is composed of three parts: definition of geometry, generation of response surface, and optimization process. To reduce the time for performance analysis and minimize the prediction errors, the approximation model is generated using the Backpropagation Artificial Neural Network (BPANN) which is considered as Neuro-Response Surface Method (NRSM). The optimization is done for the generated response surface by non-dominated sorting genetic algorithm-II (NSGA-II). Through case studies of marine system and ship structure (substructure of floating offshore wind turbine considering hydrodynamics performances and bulk carrier bottom stiffened panels considering structure performance), we have confirmed the applicability of the proposed method for multi-objective side constraint optimization problems.

  20. Multimodel Surface Temperature Responses to Removal of U.S. Sulfur Dioxide Emissions

    Science.gov (United States)

    Conley, A. J.; Westervelt, D. M.; Lamarque, J.-F.; Fiore, A. M.; Shindell, D.; Correa, G.; Faluvegi, G.; Horowitz, L. W.

    2018-03-01

    Three Earth System models are used to derive surface temperature responses to removal of U.S. anthropogenic SO2 emissions. Using multicentury perturbation runs with and without U.S. anthropogenic SO2 emissions, the local and remote surface temperature changes are estimated. In spite of a temperature drift in the control and large internal variability, 200 year simulations yield statistically significant regional surface temperature responses to the removal of U.S. SO2 emissions. Both local and remote surface temperature changes occur in all models, and the patterns of changes are similar between models for northern hemisphere land regions. We find a global average temperature sensitivity to U.S. SO2 emissions of 0.0055 K per Tg(SO2) per year with a range of (0.0036, 0.0078). We examine global and regional responses in SO4 burdens, aerosol optical depths (AODs), and effective radiative forcing (ERF). While changes in AOD and ERF are concentrated near the source region (United States), the temperature response is spread over the northern hemisphere with amplification of the temperature increase toward the Arctic. In all models, we find a significant response of dust concentrations, which affects the AOD but has no obvious effect on surface temperature. Temperature sensitivity to the ERF of U.S. SO2 emissions is found to differ from the models' sensitivity to radiative forcing of doubled CO2.

  1. 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.

  2. 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.

  3. An 80-gene set to predict response to preoperative chemoradiotherapy for rectal cancer by principle component analysis.

    Science.gov (United States)

    Empuku, Shinichiro; Nakajima, Kentaro; Akagi, Tomonori; Kaneko, Kunihiko; Hijiya, Naoki; Etoh, Tsuyoshi; Shiraishi, Norio; Moriyama, Masatsugu; Inomata, Masafumi

    2016-05-01

    Preoperative chemoradiotherapy (CRT) for locally advanced rectal cancer not only improves the postoperative local control rate, but also induces downstaging. However, it has not been established how to individually select patients who receive effective preoperative CRT. The aim of this study was to identify a predictor of response to preoperative CRT for locally advanced rectal cancer. This study is additional to our multicenter phase II study evaluating the safety and efficacy of preoperative CRT using oral fluorouracil (UMIN ID: 03396). From April, 2009 to August, 2011, 26 biopsy specimens obtained prior to CRT were analyzed by cyclopedic microarray analysis. Response to CRT was evaluated according to a histological grading system using surgically resected specimens. To decide on the number of genes for dividing into responder and non-responder groups, we statistically analyzed the data using a dimension reduction method, a principle component analysis. Of the 26 cases, 11 were responders and 15 non-responders. No significant difference was found in clinical background data between the two groups. We determined that the optimal number of genes for the prediction of response was 80 of 40,000 and the functions of these genes were analyzed. When comparing non-responders with responders, genes expressed at a high level functioned in alternative splicing, whereas those expressed at a low level functioned in the septin complex. Thus, an 80-gene expression set that predicts response to preoperative CRT for locally advanced rectal cancer was identified using a novel statistical method.

  4. A conserved two-component signal transduction system controls the response to phosphate starvation in Bifidobacterium breve UCC2003.

    Science.gov (United States)

    Alvarez-Martin, Pablo; Fernández, Matilde; O'Connell-Motherway, Mary; O'Connell, Kerry Joan; Sauvageot, Nicolas; Fitzgerald, Gerald F; MacSharry, John; Zomer, Aldert; van Sinderen, Douwe

    2012-08-01

    This work reports on the identification and molecular characterization of the two-component regulatory system (2CRS) PhoRP, which controls the response to inorganic phosphate (P(i)) starvation in Bifidobacterium breve UCC2003. The response regulator PhoP was shown to bind to the promoter region of pstSCAB, specifying a predicted P(i) transporter system, as well as that of phoU, which encodes a putative P(i)-responsive regulatory protein. This interaction is assumed to cause transcriptional modulation under conditions of P(i) limitation. Our data suggest that the phoRP genes are subject to positive autoregulation and, together with pstSCAB and presumably phoU, represent the complete regulon controlled by the phoRP-encoded 2CRS in B. breve UCC2003. Determination of the minimal PhoP binding region combined with bioinformatic analysis revealed the probable recognition sequence of PhoP, designated here as the PHO box, which together with phoRP is conserved among many high-GC-content Gram-positive bacteria. The importance of the phoRP 2CRS in the response of B. breve to P(i) starvation conditions was confirmed by analysis of a B. breve phoP insertion mutant which exhibited decreased growth under phosphate-limiting conditions compared to its parent strain UCC2003.

  5. Lactoferricin B Inhibits the Phosphorylation of the Two-Component System Response Regulators BasR and CreB*

    Science.gov (United States)

    Ho, Yu-Hsuan; Sung, Tzu-Cheng; Chen, Chien-Sheng

    2012-01-01

    Natural antimicrobial peptides provide fundamental protection for multicellular organisms from microbes, such as Lactoferricin B (Lfcin B). Many studies have shown that Lfcin B penetrates the cell membrane and has intracellular activities. To elucidate the intracellular behavior of Lfcin B, we first used Escherichia coli K12 proteome chips to identify the intracellular targets of Lfcin B. The results showed that Lfcin B binds to two response regulators, BasR and CreB, of the two-component system. For further analysis, we conducted several in vitro and in vivo experiments and utilized bioinformatics methods. The electrophoretic mobility shift assays and kinase assays indicate that Lfcin B inhibits the phosphorylation of the response regulators (BasR and CreB) and their cognate sensor kinases (BasS and CreC). Antibacterial assays showed that Lfcin B reduced E. coli's tolerance to environmental stimuli, such as excessive ferric ions and minimal medium conditions. This is the first study to show that an antimicrobial peptide inhibits the growth of bacteria by influencing the phosphorylation of a two-component system directly. PMID:22138548

  6. Lactoferricin B inhibits the phosphorylation of the two-component system response regulators BasR and CreB.

    Science.gov (United States)

    Ho, Yu-Hsuan; Sung, Tzu-Cheng; Chen, Chien-Sheng

    2012-04-01

    Natural antimicrobial peptides provide fundamental protection for multicellular organisms from microbes, such as Lactoferricin B (Lfcin B). Many studies have shown that Lfcin B penetrates the cell membrane and has intracellular activities. To elucidate the intracellular behavior of Lfcin B, we first used Escherichia coli K12 proteome chips to identify the intracellular targets of Lfcin B. The results showed that Lfcin B binds to two response regulators, BasR and CreB, of the two-component system. For further analysis, we conducted several in vitro and in vivo experiments and utilized bioinformatics methods. The electrophoretic mobility shift assays and kinase assays indicate that Lfcin B inhibits the phosphorylation of the response regulators (BasR and CreB) and their cognate sensor kinases (BasS and CreC). Antibacterial assays showed that Lfcin B reduced E. coli's tolerance to environmental stimuli, such as excessive ferric ions and minimal medium conditions. This is the first study to show that an antimicrobial peptide inhibits the growth of bacteria by influencing the phosphorylation of a two-component system directly.

  7. 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.

  8. Response Surface Design Model to Predict Surface Roughness when Machining Hastelloy C-2000 using Uncoated Carbide Insert

    International Nuclear Information System (INIS)

    Razak, N H; Rahman, M M; Kadirgama, K

    2012-01-01

    This paper presents to develop of the response surface design model to predict the surface roughness for end-milling operation of Hastelloy C-2000 using uncoated carbide insert. Mathematical model is developed to study the effect of three input cutting parameters includes the feed rate, axial depth of cut and cutting speed. Design of experiments (DOE) was implemented with the aid of the statistical software package. Analysis of variance (ANOVA) has been performed to verify the fit and adequacy of the developed mathematical model. The result shows that the feed rate gave the more effect on the both prediction values of Ra compared to the cutting speed and axial depth of cut. SEM and EDX analyses were performed in different cutting conditions. It can be concluded that the feed rate and cutting force give the higher impact to influence the machining characteristics of surface roughness. Thus, the optimizing the cutting conditions are essential in order to improve the surface roughness in machining of Hastlelloy C-2000.

  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. Using dual response surfaces to reduce variability in launch vehicle design: A case study

    International Nuclear Information System (INIS)

    Yeniay, Ozgur; Unal, Resit; Lepsch, Roger A.

    2006-01-01

    Space transportation system conceptual design is a multidisciplinary process containing considerable element of risk. Uncertainties from one engineering discipline may propagate to another through linking parameters and the final system output may have an accumulation of risk. This may lead to significant deviations from expected performance. An estimate of variability or design risk therefore becomes essential for a robust design. This study utilizes the dual response surface approach to quantify variability in critical performance characteristics during conceptual design phase of a launch vehicle. Using design of experiments methods and disciplinary design analysis codes, dual response surfaces are constructed for the mean and standard deviation to quantify variability in vehicle weight and sizing analysis. Next, an optimum solution is sought to minimize variability subject to a constraint on mean weight. In this application, the dual response surface approach lead to quantifying and minimizing variability without much increase in design effort

  11. 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.

  12. Proceedings of 1999 U.S./Japan Workshop (99FT-05) On High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices

    International Nuclear Information System (INIS)

    NYGREN, RICHARD E.; STAVROS, DIANA T.

    2000-01-01

    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

  13. Application of response surface methodology for optimizing transesterification of Moringa oleifera oil: Biodiesel production

    International Nuclear Information System (INIS)

    Rashid, Umer; Anwar, Farooq; Ashraf, Muhammad; Saleem, Muhammad; Yusup, Suzana

    2011-01-01

    Highlights: → Biodiesel production from Moringa oil (MO) has been optimized for the first time using RSM. → RSM-optimized reaction conditions gave a high Moringa oil methyl esters (MOMEs) yield (94.3%). → Fuel properties of MOMEs yielded satisfied the ASTM D 6751 and EU 14214 specifications. → Present RSM-model can be useful for predicting optimum biodiesel yield from other oils. - Abstract: Response surface methodology (RSM), with central composite rotatable design (CCRD), was used to explore optimum conditions for the transesterification of Moringa oleifera oil. Effects of four variables, reaction temperature (25-65 deg. C), reaction time (20-90 min), methanol/oil molar ratio (3:1-12:1) and catalyst concentration (0.25-1.25 wt.% KOH) were appraised. The quadratic term of methanol/oil molar ratio, catalyst concentration and reaction time while the interaction terms of methanol/oil molar ratio with reaction temperature and catalyst concentration, reaction time with catalyst concentration exhibited significant effects on the yield of Moringa oil methyl esters (MOMEs)/biodiesel, p < 0.0001 and p < 0.05, respectively. Transesterification under the optimum conditions ascertained presently by RSM: 6.4:1 methanol/oil molar ratio, 0.80% catalyst concentration, 55 deg. C reaction temperature and 71.08 min reaction time offered 94.30% MOMEs yield. The observed and predicted values of MOMEs yield showed a linear relationship. GLC analysis of MOMEs revealed oleic acid methyl ester, with contribution of 73.22%, as the principal component. Other methyl esters detected were of palmitic, stearic, behenic and arachidic acids. Thermal stability of MOMEs produced was evaluated by thermogravimetric curve. The fuel properties such as density, kinematic viscosity, lubricity, oxidative stability, higher heating value, cetane number and cloud point etc., of MOMEs were found to be within the ASTM D6751 and EN 14214 biodiesel standards.

  14. 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.

  15. Application of response surface methodology for optimizing transesterification of Moringa oleifera oil: Biodiesel production

    Energy Technology Data Exchange (ETDEWEB)

    Rashid, Umer, E-mail: umer.rashid@yahoo.com [Department of Chemistry and Biochemistry, University of Agriculture, Faisalabad 38040 (Pakistan); Chemical Engineering Department, Universiti Teknologi PETRONAS, Bandar Seri Iskandar 31750, Tronoh, Perak (Malaysia); Anwar, Farooq, E-mail: fqanwar@yahoo.com [Department of Chemistry and Biochemistry, University of Agriculture, Faisalabad 38040 (Pakistan); Ashraf, Muhammad, E-mail: ashrafbot@yahoo.com [Department of Botany, University of Agriculture, Faisalabad 38040 (Pakistan); Department of Botany and Microbiology, King Saud University, Riyadh (Saudi Arabia); Saleem, Muhammad [Department of Statistics, Government College University, Faisalabad 38000 (Pakistan); Yusup, Suzana, E-mail: drsuzana_yusuf@petronas.com.my [Chemical Engineering Department, Universiti Teknologi PETRONAS, Bandar Seri Iskandar 31750, Tronoh, Perak (Malaysia)

    2011-08-15

    Highlights: {yields} Biodiesel production from Moringa oil (MO) has been optimized for the first time using RSM. {yields} RSM-optimized reaction conditions gave a high Moringa oil methyl esters (MOMEs) yield (94.3%). {yields} Fuel properties of MOMEs yielded satisfied the ASTM D 6751 and EU 14214 specifications. {yields} Present RSM-model can be useful for predicting optimum biodiesel yield from other oils. - Abstract: Response surface methodology (RSM), with central composite rotatable design (CCRD), was used to explore optimum conditions for the transesterification of Moringa oleifera oil. Effects of four variables, reaction temperature (25-65 deg. C), reaction time (20-90 min), methanol/oil molar ratio (3:1-12:1) and catalyst concentration (0.25-1.25 wt.% KOH) were appraised. The quadratic term of methanol/oil molar ratio, catalyst concentration and reaction time while the interaction terms of methanol/oil molar ratio with reaction temperature and catalyst concentration, reaction time with catalyst concentration exhibited significant effects on the yield of Moringa oil methyl esters (MOMEs)/biodiesel, p < 0.0001 and p < 0.05, respectively. Transesterification under the optimum conditions ascertained presently by RSM: 6.4:1 methanol/oil molar ratio, 0.80% catalyst concentration, 55 deg. C reaction temperature and 71.08 min reaction time offered 94.30% MOMEs yield. The observed and predicted values of MOMEs yield showed a linear relationship. GLC analysis of MOMEs revealed oleic acid methyl ester, with contribution of 73.22%, as the principal component. Other methyl esters detected were of palmitic, stearic, behenic and arachidic acids. Thermal stability of MOMEs produced was evaluated by thermogravimetric curve. The fuel properties such as density, kinematic viscosity, lubricity, oxidative stability, higher heating value, cetane number and cloud point etc., of MOMEs were found to be within the ASTM D6751 and EN 14214 biodiesel standards.

  16. Medium optimization for the production of recombinant nattokinase by Bacillus subtilis using response surface methodology.

    Science.gov (United States)

    Chen, Po Ting; Chiang, Chung-Jen; Chao, Yun-Peng

    2007-01-01

    Nattokinase is a potent fibrinolytic enzyme with the potential for fighting cardiovascular diseases. Most recently, a new Bacillus subtilis/Escherichia coli (B. subtilis/E. coli) shuttle vector has been developed to achieve stable production of recombinant nattokinase in B. subtilis (Chen; et al. 2007, 23, 808-813). With this developed B. subtilis strain, the design of an optimum but cost-effective medium for high-level production of recombinant nattokinase was attempted by using response surface methodology. On the basis of the Plackett-Burman design, three critical medium components were selected. Subsequently, the optimum combination of selected factors was investigated by the Box-Behnken design. As a result, it gave the predicted maximum production of recombinant nattokinase with 71 500 CU/mL for shake-flask cultures when the concentrations of soybean hydrolysate, potassium phosphate, and calcium chloride in medium were at 6.100, 0.415, and 0.015%, respectively. This was further verified by a duplicated experiment. Moreover, the production scheme based on the optimum medium was scaled up in a fermenter. The batch fermentation of 3 L was carried out by controlling the condition at 37 degrees C and dissolved oxygen reaching 20% of air saturation level while the fermentation pH was initially set at 8.5. Without the need for controlling the broth pH, recombinant nattokinase production with a yield of 77 400 CU/mL (corresponding to 560 mg/L) could be obtained in the culture broth within 24 h. In particular, the recombinant B. subtilis strain was found fully stable at the end of fermentation when grown on the optimum medium. Overall, it indicates the success of this experimental design approach in formulating a simple and cost-effective medium, which provides the developed strain with sufficient nutrient supplements for stable and high-level production of recombinant nattokinase in a fermenter.

  17. 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.

  18. Optimization of the extraction of flavonoids from grape leaves by response surface methodology

    International Nuclear Information System (INIS)

    Brad, K.; Liu, W.

    2013-01-01

    The extraction of flavonoids from grape leaves was optimized to maximize flavonoids yield in this study. A central composite design of response surface methodology involving extracting time, power, liquid-solid ratio, and concentration was used, and second-order model for Y was employed to generate the response surfaces. The optimum condition for flavonoids yield was determined as follows: extracting time 24.95 min, power 72.05, ethanol concentration 63.35%, liquid-solid ratio 10.04. Under the optimum condition, the flavonoids yield was 76.84 %. (author)

  19. Adaptation response surfaces for managing wheat under perturbed climate and CO2 in a Mediterranean environment

    DEFF Research Database (Denmark)

    Ruiz-Ramos, M.; Ferrise, Roberto; Rodríguez, A

    2018-01-01

    type were analysed by constructing response surfaces, which we termed, in accordance with their specific purpose, adaptation response surfaces (ARSs). These were created to assess the effect of adaptations through a range of plausible P, T and [CO2] perturbations. The results indicated that impacts....... However, a single sI was sufficient to develop a high adaptation potential, including options mainly based on spring wheat, current cycle duration and early sowing date. Depending on local environment (e.g. soil type), many of these adaptations can maintain current yield levels under moderate changes in T...

  20. Response of Antarctic sea surface temperature and sea ice to ozone depletion

    Science.gov (United States)

    Ferreira, D.; Gnanadesikan, A.; Kostov, Y.; Marshall, J.; Seviour, W.; Waugh, D.

    2017-12-01

    The influence of the Antarctic ozone hole extends all the way from the stratosphere through the troposphere down to the surface, with clear signatures on surface winds, and SST during summer. In this talk we discuss the impact of these changes on the ocean circulation and sea ice state. We are notably motivated by the observed cooling of the surface Southern Ocean and associated increase in Antarctic sea ice extent since the 1970s. These trends are not reproduced by CMIP5 climate models, and the underlying mechanism at work in nature and the models remain unexplained. Did the ozone hole contribute to the observed trends?Here, we review recent advances toward answering these issues using "abrupt ozone depletion" experiments. The ocean and sea ice response is rather complex, comprising two timescales: a fast ( 1-2y) cooling of the surface ocean and sea ice cover increase, followed by a slower warming trend, which, depending on models, flip the sign of the SST and sea ice responses on decadal timescale. Although the basic mechanism seems robust, comparison across climate models reveal large uncertainties in the timescales and amplitude of the response to the extent that even the sign of the ocean and sea ice response to ozone hole and recovery remains unconstrained. After briefly describing the dynamics and thermodynamics behind the two-timescale response, we will discuss the main sources of uncertainties in the modeled response, namely cloud effects and air-sea heat exchanges, surface wind stress response and ocean eddy transports. Finally, we will consider the implications of our results on the ability of coupled climate models to reproduce observed Southern Ocean changes.

  1. Micro- and nano-scale damage on the surface of W divertor component during exposure to high heat flux loads with He

    International Nuclear Information System (INIS)

    Li, C.; Greuner, H.; Zhao, S.X.; Böswirth, B.; Luo, G.N.; Zhou, X.; Jia, Y.Z.; Liu, X.; Liu, W.

    2015-01-01

    Micro- and nano-scale surface damage on a W divertor component sample exposed to high heat flux loads generated with He atoms has been investigated through SEM, EBSD, AFM and FIB-SEM. The component sample was supplied by the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP) and AT&M company, China, and the loading experiment was performed in the GLADIS facility at IPP Garching, Germany. Two typical damage structures were observed on the surface: the first one is characterized by obvious blisters and some grooves formed from ruptured blisters, and the other one is a kind of porous structure accompanying with at least ∼25 nm surface material loss. As the grain orientation is further away from , the damage morphology gradually changes from the former structure to the latter. The possible damage mechanism is discussed. - Highlights: • Two damage structures were observed on W component surface under He beam heating. • Blistering was more obvious in near grains. • Porous structure appeared in the grains away from . • A loose layer caused by He aggregation was formed in near-surface region.

  2. Application of Response Surface Methodology (RSM) for wastewater of hospital by using electrocoagulation

    Science.gov (United States)

    Murdani; Jakfar; Ekawati, D.; Nadira, R.; Darmadi

    2018-04-01

    Hospital wastewater is a source of potential environmental contamination. Therefore, the waste water needs to be treated before it is discharged into the landfill. Various research methods have been used to treat hospital wastewater. However, some methods that have been implemented have not achieved the effluent standards for hospitals that have been set by the government. The experiment was conducted by an electrochemical method is electrolysis using aluminum electrodes with independent variable is the voltage, contact time and concentration of electrolytes. The response optimization using response surface with optimum conditions obtained by the contact time of 34.26 min, voltage 12 V, concentration electrolyte 0.38 M can decrease of COD 65.039%. The model recommended by the response surface for the three variables, namely quadratic response.

  3. Pulmonary epithelial response in the rat lung to instilled Montserrat respirable dusts and their major mineral components.

    Science.gov (United States)

    Housley, D G; Bérubé, K A; Jones, T P; Anderson, S; Pooley, F D; Richards, R J

    2002-07-01

    The Soufriere Hills, a stratovolcano on Montserrat, started erupting in July 1995, producing volcanic ash, both from dome collapse pyroclastic flows and phreatic explosions. The eruptions/ash resuspension result in high concentrations of suspended particulate matter in the atmosphere, which includes cristobalite, a mineral implicated in respiratory disorders. To conduct toxicological studies on characterised samples of ash, together with major components of the dust mixture (anorthite, cristobalite), and a bioreactive mineral control (DQ12 quartz). Rats were challenged with a single mass (1 mg) dose of particles via intratracheal instillation and groups sacrificed at one, three, and nine weeks. Acute bioreactivity of the particles was assessed by increases in lung permeability and inflammation, changes in epithelial cell markers, and increase in the size of bronchothoracic lymph nodes. Data indicated that respirable ash derived from pyroclastic flows (20.1% cristobalite) or phreatic explosion (8.6% cristobalite) had minimal bioreactivity in the lung. Anorthite showed low bioreactivity, in contrast to pure cristobalite, which showed progressive increases in lung damage. Results suggests that either the percentage mass of cristobalite particles present in Montserrat ash was not sufficient as a catalyst in the lung environment, or its surface reactivity was masked by the non-reactive volcanic glass components during the process of ash formation.

  4. Characterization of Silk Fibroin Modified Surface: A Proteomic View of Cellular Response Proteins Induced by Biomaterials

    Directory of Open Access Journals (Sweden)

    Ming-Hui Yang

    2014-01-01

    Full Text Available The purpose of this study was to develop the pathway of silk fibroin (SF biopolymer surface induced cell membrane protein activation. Fibroblasts were used as an experimental model to evaluate the responses of cellular proteins induced by biopolymer material using a mass spectrometry-based profiling system. The surface was covered by multiwalled carbon nanotubes (CNTs and SF to increase the surface area, enhance the adhesion of biopolymer, and promote the rate of cell proliferation. The amount of adhered fibroblasts on CNTs/SF electrodes of quartz crystal microbalance (QCM greatly exceeded those on other surfaces. Moreover, analyzing differential protein expressions of adhered fibroblasts on the biopolymer surface by proteomic approaches indicated that CD44 may be a key protein. Through this study, utilization of mass spectrometry-based proteomics in evaluation of cell adhesion on biopolymer was proposed.

  5. Light-responsive smart surface with controllable wettability and excellent stability.

    Science.gov (United States)

    Zhou, Yin-Ning; Li, Jin-Jin; Zhang, Qing; Luo, Zheng-Hong

    2014-10-21

    Novel fluorinated gradient copolymer was designed for smart surface with light-responsive controllable wettability and excellent stability. The switchable mechanism and physicochemical characteristics of the as-prepared surface decorated by designed polymeric material were investigated by ultraviolet-visible (UV-vis) spectrum, scanning electron microscope (SEM), atomic force microscope (AFM), and X-ray photoelectron spectroscopy (XPS). Thanks to the functional film and surface roughening, etched silicon surface fabricated by copolymer involving spiropyran (Sp) moieties possesses a fairly large variation range of WCA (28.1°) and achieves the transformation between hydrophilicity (95.2° 109.2°) relative to blank sample (109.2°). The synthetic strategy and developed smart surface offer a promising application in coating with controllable wettability, which bridge the gap between chemical structure and material properties.

  6. Early human bone response to laser metal sintering surface topography: a histologic report.

    Science.gov (United States)

    Mangano, Carlo; Piattelli, Adriano; d'Avila, Susana; Iezzi, Giovanna; Mangano, Francesco; Onuma, Tatiana; Shibli, Jamil Awad

    2010-01-01

    This histologic report evaluated the early human bone response to a direct laser metal sintering implant surface retrieved after a short period of healing. A selective laser sintering procedure using a Ti-6Al-4V alloy powder with a particle size of 25-45 microm prepared this surface topography. One experimental microimplant was inserted into the anterior mandible of a patient during conventional implant surgery of the jaw. The microimplant and surrounding tissues were removed after 2 months of unloaded healing and were prepared for histomorphometric analysis. Histologically, the peri-implant bone appeared in close contact with the implant surface, whereas marrow spaces could be detected in other areas along with prominently stained cement lines. The mean of bone-to-implant contact was 69.51%. The results of this histologic report suggest that the laser metal sintering surface could be a promising alternative to conventional implant surface topographies.

  7. A Comparison of Two Objective Measures of Binaural Processing: The Interaural Phase Modulation Following Response and the Binaural Interaction Component.

    Science.gov (United States)

    Haywood, Nicholas R; Undurraga, Jaime A; Marquardt, Torsten; McAlpine, David

    2015-12-30

    There has been continued interest in clinical objective measures of binaural processing. One commonly proposed measure is the binaural interaction component (BIC), which is obtained typically by recording auditory brainstem responses (ABRs)-the BIC reflects the difference between the binaural ABR and the sum of the monaural ABRs (i.e., binaural - (left + right)). We have recently developed an alternative, direct measure of sensitivity to interaural time differences, namely, a following response to modulations in interaural phase difference (the interaural phase modulation following response; IPM-FR). To obtain this measure, an ongoing diotically amplitude-modulated signal is presented, and the interaural phase difference of the carrier is switched periodically at minima in the modulation cycle. Such periodic modulations to interaural phase difference can evoke a steady state following response. BIC and IPM-FR measurements were compared from 10 normal-hearing subjects using a 16-channel electroencephalographic system. Both ABRs and IPM-FRs were observed most clearly from similar electrode locations-differential recordings taken from electrodes near the ear (e.g., mastoid) in reference to a vertex electrode (Cz). Although all subjects displayed clear ABRs, the BIC was not reliably observed. In contrast, the IPM-FR typically elicited a robust and significant response. In addition, the IPM-FR measure required a considerably shorter recording session. As the IPM-FR magnitude varied with interaural phase difference modulation depth, it could potentially serve as a correlate of perceptual salience. Overall, the IPM-FR appears a more suitable clinical measure than the BIC. © The Author(s) 2015.

  8. Influence of activated carbon characteristics on toluene and hexane adsorption: Application of surface response methodology

    Science.gov (United States)

    Izquierdo, Mª Teresa; de Yuso, Alicia Martínez; Valenciano, Raquel; Rubio, Begoña; Pino, Mª Rosa

    2013-01-01

    The objective of this study was to evaluate the adsorption capacity of toluene and hexane over activated carbons prepared according an experimental design, considering as variables the activation temperature, the impregnation ratio and the activation time. The response surface methodology was applied to optimize the adsorption capacity of the carbons regarding the preparation conditions that determine the physicochemical characteristics of the activated carbons. The methodology of preparation produced activated carbons with surface areas and micropore volumes as high as 1128 m2/g and 0.52 cm3/g, respectively. Moreover, the activated carbons exhibit mesoporosity, ranging from 64.6% to 89.1% the percentage of microporosity. The surface chemistry was characterized by TPD, FTIR and acid-base titration obtaining different values of surface groups from the different techniques because the limitation of each technique, but obtaining similar trends for the activated carbons studied. The exhaustive characterization of the activated carbons allows to state that the measured surface area does not explain the adsorption capacity for either toluene or n-hexane. On the other hand, the surface chemistry does not explain the adsorption results either. A compromise between physical and chemical characteristics can be obtained from the appropriate activation conditions, and the response surface methodology gives the optimal activated carbon to maximize adsorption capacity. Low activation temperature, intermediate impregnation ratio lead to high toluene and n-hexane adsorption capacities depending on the activation time, which a determining factor to maximize toluene adsorption.

  9. Shear wave profiles from surface wave inversion: the impact of uncertainty on seismic site response analysis

    International Nuclear Information System (INIS)

    Boaga, J; Vignoli, G; Cassiani, G

    2011-01-01

    Inversion is a critical step in all geophysical techniques, and is generally fraught with ill-posedness. In the case of seismic surface wave studies, the inverse problem can lead to different equivalent subsoil models and consequently to different local seismic response analyses. This can have a large impact on an earthquake engineering design. In this paper, we discuss the consequences of non-uniqueness of surface wave inversion on seismic responses, with both numerical and experimental data. Our goal is to evaluate the consequences on common seismic response analysis in the case of different impedance contrast conditions. We verify the implications of inversion uncertainty, and consequently of data information content, on realistic local site responses. A stochastic process is used to generate a set of 1D shear wave velocity profiles from several specific subsurface models. All these profiles are characterized as being equivalent, i.e. their responses, in terms of a dispersion curve, are compatible with the uncertainty in the same surface wave data. The generated 1D shear velocity models are then subjected to a conventional one-dimensional seismic ground response analysis using a realistic input motion. While recent analyses claim that the consequences of surface wave inversion uncertainties are very limited, our test points out that a relationship exists between inversion confidence and seismic responses in different subsoils. In the case of regular and relatively smooth increase of shear wave velocities with depth, as is usual in sedimentary plains, our results show that the choice of a specific model among equivalent solutions strongly influences the seismic response. On the other hand, when the shallow subsoil is characterized by a strong impedance contrast (thus revealing a characteristic soil resonance period), as is common in the presence of a shallow bedrock, equivalent solutions provide practically the same seismic amplification, especially in the

  10. Genetic parameters and expected responses to selection for components of feed efficiency in a Duroc pig line.

    Science.gov (United States)

    Sánchez, Juan P; Ragab, Mohamed; Quintanilla, Raquel; Rothschild, Max F; Piles, Miriam

    2017-12-01

    Improving feed efficiency ([Formula: see text]) is a key factor for any pig breeding company. Although this can be achieved by selection on an index of multi-trait best linear unbiased prediction of breeding values with optimal economic weights, considering deviations of feed intake from actual needs ([Formula: see text]) should be of value for further research on biological aspects of [Formula: see text]. Here, we present a random regression model that extends the classical definition of [Formula: see text] by including animal-specific needs in the model. Using this model, we explore the genetic determinism of several [Formula: see text] components: use of feed for growth ([Formula: see text]), use of feed for backfat deposition ([Formula: see text]), use of feed for maintenance ([Formula: see text]), and unspecific efficiency in the use of feed ([Formula: see text]). Expected response to alternative selection indexes involving different components is also studied. Based on goodness-of-fit to the available feed intake ([Formula: see text]) data, the model that assumes individual (genetic and permanent) variation in the use of feed for maintenance, [Formula: see text] and [Formula: see text] showed the best performance. Joint individual variation in feed allocation to maintenance, growth and backfat deposition comprised 37% of the individual variation of [Formula: see text]. The estimated heritabilities of [Formula: see text] using the model that accounts for animal-specific needs and the traditional [Formula: see text] model were 0.12 and 0.18, respectively. The estimated heritabilities for the regression coefficients were 0.44, 0.39 and 0.55 for [Formula: see text], [Formula: see text] and [Formula: see text], respectively. Estimates of genetic correlations of [Formula: see text] were positive with amount of feed used for [Formula: see text] and [Formula: see text] but negative for [Formula: see text]. Expected response in overall efficiency, reducing [Formula

  11. In vivo modulation of foreign body response on polyurethane by surface entrapment technique.

    Science.gov (United States)

    Khandwekar, Anand P; Patil, Deepak P; Hardikar, Anand A; Shouche, Yogesh S; Doble, Mukesh

    2010-11-01

    Implanted polymeric materials, such as medical devices, provoke the body to initiate an inflammatory reaction, known as the foreign body response (FBR), which causes several complications. In this study, polyurethane (Tecoflex®, PU) surface modified with the nonionic surfactant Tween80® (PU/T80) and the cell adhesive PLL-RGD peptide (PU/PLL-RGD) by a previously described entrapment technique were implanted in the peritoneal cavity of Wistar rats for 30 days. Implants were retrieved and examined for tissue reactivity and cellular adherence by various microscopic and analytical techniques. Surface-induced inflammatory response was assessed by real-time PCR based quantification of proinflammatory cytokine transcripts, namely, TNF-α and IL-1β, normalized to housekeeping gene GAPDH. Cellular adherence and their distribution profile were assessed by microscopic examination of H&E stained implant sections. It was observed that PU/PLL-RGD followed by the bare PU surface exhibited severe inflammatory and fibrotic response with an average mean thickness of 19 and 12 μm, respectively, in 30 days. In contrast, PU/T80 surface showed only a cellular monolayer of 2-3 μm in thickness, with a mild inflammatory response and no fibrotic encapsulation. The PU/PLL-RGD peptide-modified substrate promoted an enhanced rate of macrophage cell fusion to form foreign body giant cell (FBGCs), whereas FBGCs were rarely observed on Tween80®-modified substrate. The expression levels of proinflammatory cytokines (TNF-α and IL-1β) were upregulated on PU/PLL-RGD surface followed by bare PU, whereas the cytokine expressions were significantly suppressed on PU/T80 surface. Thus, our study highlights modulation of foreign body response on polyurethane surfaces through surface entrapment technique in the form of differential responses observed on PLL-RGD and Tween80® modified surfaces with the former effective in triggering tissue cell adhesion thereby fibrous encapsulation, while the later

  12. The adult brain tissue response to hollow fiber membranes of varying surface architecture with or without cotransplanted cells

    Science.gov (United States)

    Zhang, Ning

    A variety of biomaterials have been chronically implanted into the central nervous system (CNS) for repair or therapeutic purposes. Regardless of the application, chronic implantation of materials into the CNS induces injury and elicits a wound healing response, eventually leading to the formation of a dense extracellular matrix (ECM)-rich scar tissue that is associated with the segregation of implanted materials from the surrounding normal tissue. Often this reaction results in impaired performance of indwelling CNS devices. In order to enhance the performance of biomaterial-based implantable devices in the CNS, this thesis investigated whether adult brain tissue response to implanted biomaterials could be manipulated by changing biomaterial surface properties or further by utilizing the biology of co-transplanted cells. Specifically, the adult rat brain tissue response to chronically implanted poly(acrylonitrile-vinylchloride) (PAN-PVC) hollow fiber membranes (HFMs) of varying surface architecture were examined temporally at 2, 4, and 12 weeks postimplantation. Significant differences were discovered in the brain tissue response to the PAN-PVC HFMs of varying surface architecture at 4 and 12 weeks. To extend this work, whether the soluble factors derived from a co-transplanted cellular component further affect the brain tissue response to an implanted HFM in a significant way was critically exploited. The cells used were astrocytes, whose ability to influence scar formation process following CNS injury by physical contact with the host tissue had been documented in the literature. Data indicated for the first time that astrocyte-derived soluble factors ameliorate the adult brain tissue reactivity toward HFM implants in an age-dependent manner. While immature astrocytes secreted soluble factors that suppressed the brain tissue reactivity around the implants, mature astrocytes secreted factors that enhanced the gliotic response. These findings prove the feasibility

  13. Electronic energy transfer from molecules to metal and semiconductor surfaces, and chemisorption-induced changes in optical response of the nickel (111) surface

    International Nuclear Information System (INIS)

    Whitmore, P.M.

    1982-10-01

    The evolution of molecular excited states near solid surfaces is investigated. The mechanisms through which energy is transferred to the surface are described within a classical image dipole picture of the interaction. More sophisticated models for the dielectric response of the solid surface add important new decay channels for the energy dissipation. The predictions and applicability of three of these refined theories are discussed

  14. Northern Alaskan land surface response to reduced Arctic sea ice extent

    Energy Technology Data Exchange (ETDEWEB)

    Higgins, Matthew E. [University of Colorado, Cooperative Institute for Research in Environmental Sciences, Boulder, CO (United States); Cassano, John J. [University of Colorado, Cooperative Institute for Research in Environmental Sciences, Department of Atmospheric and Oceanic Sciences, Boulder, CO (United States)

    2012-05-15

    With Arctic sea ice extent at near-record lows, an improved understanding of the relationship between sea ice and the land surface is warranted. We examine the land surface response to changing sea ice by first conducting a simulation using the Community Atmospheric Model version 3.1 with end of the twenty-first century sea ice extent. This future atmospheric response is then used to force the Weather and Research Forecasting Model version 3.1 to examine the terrestrial land surface response at high resolution over the North Slope of Alaska. Similar control simulations with twentieth century sea ice projections are also performed, and in both simulations only sea ice extent is altered. In the future sea ice extent experiment, atmospheric temperature increases significantly due to increases in latent and sensible heat flux, particularly in the winter season. Precipitation and snow pack increase significantly, and the increased snow pack contributes to warmer soil temperatures for most seasons by insulating the land surface. In the summer, however, soil temperatures are reduced due to increased albedo. Despite warmer near-surface atmospheric temperatures, it is found that spring melt is delayed throughout much of the North Slope due to the increased snow pack, and the growing season length is shortened. (orig.)

  15. Chemosensory responsiveness to ethanol and its individual sensory components in alcohol-preferring, -nonpreferring and genetically heterogeneous rats

    Science.gov (United States)

    Brasser, Susan M.; Silbaugh, Bryant C.; Ketchum, Myles J.; Olney, Jeffrey J.; Lemon, Christian H.

    2011-01-01

    Alcohol activates orosensory circuits that project to motivationally relevant limbic forebrain areas that control appetite, feeding and drinking. To date, limited data exists regarding the contribution of chemosensory-derived ethanol reinforcement to ethanol preference and consumption. Measures of taste reactivity to intra-orally infused ethanol have not found differences in initial orofacial responses to alcohol between alcohol-preferring (P) and – nonpreferring (NP) genetically selected rat lines. Yet, in voluntary intake tests P rats prefer highly-concentrated ethanol upon initial exposure, suggesting an early sensory-mediated attraction. Here, we directly compared self-initiated chemosensory responding for alcohol and prototypic sweet, bitter, and oral trigeminal stimuli among selectively bred P, NP, and non-selected Wistar (WI) outbred lines to determine whether differential sensory responsiveness to ethanol and its putative sensory components are phenotypically associated with genetically-influenced alcohol preference. Rats were tested for immediate short-term lick responses to alcohol (3–40%), sucrose (0.01–1 M), quinine (0.01–3 mM) and capsaicin (0.003–1 mM) in a brief-access assay designed to index orosensory-guided behavior. P rats exhibited elevated short-term lick responses to both alcohol and sucrose relative to NP and WI lines across a broad range of concentrations of each stimulus and in the absence of blood alcohol levels that would produce significant postabsorptive effects. There was no consistent relationship between genetically-mediated alcohol preference and orosensory avoidance of quinine or capsaicin. These data indicate that enhanced initial chemosensory attraction to ethanol and sweet stimuli are phenotypes associated with genetic alcohol preference and are considered within the framework of downstream activation of oral appetitive reward circuits. PMID:22129513

  16. Chemosensory responsiveness to ethanol and its individual sensory components in alcohol-preferring, alcohol-nonpreferring and genetically heterogeneous rats.

    Science.gov (United States)

    Brasser, Susan M; Silbaugh, Bryant C; Ketchum, Myles J; Olney, Jeffrey J; Lemon, Christian H

    2012-03-01

    Alcohol activates orosensory circuits that project to motivationally relevant limbic forebrain areas that control appetite, feeding and drinking. To date, limited data exists regarding the contribution of chemosensory-derived ethanol reinforcement to ethanol preference and consumption. Measures of taste reactivity to intra-orally infused ethanol have not found differences in initial orofacial responses to alcohol between alcohol-preferring (P) and alcohol-non-preferring (NP) genetically selected rat lines. Yet, in voluntary intake tests, P rats prefer highly concentrated ethanol upon initial exposure, suggesting an early sensory-mediated attraction. Here, we directly compared self-initiated chemosensory responding for alcohol and prototypic sweet, bitter and oral trigeminal stimuli among selectively bred P, NP and non-selected Wistar (WI) outbred lines to determine whether differential sensory responsiveness to ethanol and its putative sensory components are phenotypically associated with genetically influenced alcohol preference. Rats were tested for immediate short-term lick responses to alcohol (3-40%), sucrose (0.01-1 M), quinine (0.01-3 mM) and capsaicin (0.003-1 mM) in a brief-access assay designed to index orosensory-guided behavior. P rats exhibited elevated short-term lick responses to both alcohol and sucrose relative to NP and WI lines across a broad range of concentrations of each stimulus and in the absence of blood alcohol levels that would produce significant post-absorptive effects. There was no consistent relationship between genetically mediated alcohol preference and orosensory avoidance of quinine or capsaicin. These data indicate that enhanced initial chemosensory attraction to ethanol and sweet stimuli are phenotypes associated with genetic alcohol preference and are considered within the framework of downstream activation of oral appetitive reward circuits. © 2011 The Authors, Addiction Biology © 2011 Society for the Study of

  17. Inverse modeling of cloud-aerosol interactions -- Part 1: Detailed response surface analysis

    NARCIS (Netherlands)

    Partridge, D.G.; Vrugt, J.A.; Tunved, P.; Ekman, A.M.L.; Gorea, D.; Sooroshian, A.

    2011-01-01

    New methodologies are required to probe the sensitivity of parameters describing cloud droplet activation. This paper presents an inverse modeling-based method for exploring cloud-aerosol interactions via response surfaces. The objective function, containing the difference between the measured and

  18. Optimization of lysine production in Corynebacteriumglutamicum ATCC15032 by Response surface methodology

    Directory of Open Access Journals (Sweden)

    Mehrnaz Haghi

    2017-03-01

    Discussion and conclusion: According to the results, the proposed culture media by response surface methodology causes 1400 times increase in the lysine production compared with M9 culture media and methionine had an important role in the production of lysine, probably by inhibiting the other metabolic pathway which has common metabolic precursor with lysine production metabolic pathway.

  19. Cellular Stress Response to Engineered Nanoparticles: Effect of Size, Surface Coating, and Cellular Uptake

    Science.gov (United States)

    CELLULAR STRESS RESPONSE TO ENGINEERED NANOPARTICLES: EFFECT OF SIZE, SURFACE COATING, AND CELLULAR UPTAKE RY Prasad 1, JK McGee2, MG Killius1 D Ackerman2, CF Blackman2 DM DeMarini2 , SO Simmons2 1 Student Services Contractor, US EPA, RTP, NC 2 US EPA, RTP, NC The num...

  20. Accelerating solving the dynamic multi-objective nework design problem using response surface methods

    NARCIS (Netherlands)

    Wismans, Luc Johannes Josephus; van Berkum, Eric C.; Bliemer, Michiel C.J.; Viti, F.; Immers, B.; Tampere, C.

    2011-01-01

    Multi objective optimization of externalities of traffic solving a network design problem in which Dynamic Traffic Management measures are used, is time consuming while heuristics are needed and solving the lower level requires solving the dynamic user equilibrium problem. Use of response surface

  1. Optimization of dyeing wool fibers procedure with Isatis tinctoria by Response Surface Methodology

    NARCIS (Netherlands)

    Barani, H.; Nasiriboroumand, Majid; Haji, A.; Kazemipour, M.

    2012-01-01

    The response surface method (RMS) was used to optimize the color strength (K/S) of the wool fibers dyed with Isatis tinctoria. The eight independent variable terms, in which two of them are categorical and the other six numerical, were selected at two levels (low and high). The ANOVA test results of

  2. Simultaneous saccharification and ethanol fermentation of oxalic acid pretreated corncob assessed with response surface methodology

    Science.gov (United States)

    Jae-Won Lee; Rita C.L.B. Rodrigues; Thomas W. Jeffries

    2009-01-01

    Response surface methodology was used to evaluate optimal time, temperature and oxalic acid concentration for simultaneous saccharification and fermentation (SSF) of corncob particles by Pichia stipitis CBS 6054. Fifteen different conditions for pretreatment were examined in a 23 full factorial design with six axial points. Temperatures ranged from 132 to 180º...

  3. Analyzing containment leakage from a sodium fire by the response surface method

    International Nuclear Information System (INIS)

    Person, L.W.

    1978-01-01

    The SPOOL-FIRE code has been used with the response surface method and a Monte Carlo simulation to study sodium fire accidents. The study provides a simple method of estimating the radioactive release via containment leakage; the sensitivity of the output consequences to the variations in the input parameters is also presented

  4. Preparation of antinutrients-reduced dhokla using response surface process optimisation

    NARCIS (Netherlands)

    Sharma, Anand; Kumari, Sarita; Nout, Martinus J.R.; Sarkar, Prabir K.

    2018-01-01

    Dhokla, a popular indigenous savoury dish of India, is prepared by soaking bengalgram dal and rice, grinding separately, mixing the batters, and spontaneously fermenting and steaming of mixed batter. Central composite rotatable response surface designs for soaking, fermentation and steaming at

  5. 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...

  6. Production of specific structured lipids by enzymatic interesterification: optimization of the reaction by response surface design

    DEFF Research Database (Denmark)

    Xu, Xuebing; Skands, Anja Rebecca Havegaard; Adler-Nissen, Jens

    1998-01-01

    Rapeseed oil and capric acid were interesterified in solvent-free media catalyzed by Lipozyme IM (Rhizomucor miehei) to produce specific-structured lipids (SSLs). The process was optimized by response surface design concerning the effects of acyl migration and the by-products of diacylglycerols...

  7. Understanding the Asian summer monsoon response to greenhouse warming: the relative roles of direct radiative forcing and sea surface temperature change

    Science.gov (United States)

    Li, Xiaoqiong; Ting, Mingfang

    2017-10-01

    Future hydroclimate projections from state-of-the-art climate models show large uncertainty and model spread, particularly in the tropics and over the monsoon regions. The precipitation and circulation responses to rising greenhouse gases involve a fast component associated with direct radiative forcing and a slow component associated with sea surface temperature (SST) warming; the relative importance of the two may contribute to model discrepancies. In this study, regional hydroclimate responses to greenhouse warming are assessed using output from coupled general circulation models in the Coupled Model Intercomparison Project-Phase 5 (CMIP5) and idealized atmospheric general circulation model experiments from the Atmosphere Model Intercomparison Project. The thermodynamic and dynamic mechanisms causing the rainfall changes are examined using moisture budget analysis. Results show that direct radiative forcing and SST change exert significantly different responses both over land and ocean. For most part of the Asian monsoon region, the summertime rainfall changes are dominated by the direct CO2 radiative effect through enhanced monsoon circulation. The response to SST warming shows a larger model spread compared to direct radiative forcing, possibly due to the cancellation between the thermodynamical and dynamical components. While the thermodynamical response of the Asian monsoon is robust across the models, there is a lack of consensus for the dynamical response among the models and weak multi-model mean responses in the CMIP5 ensemble, which may be related to the multiple physical processes evolving on different time scales.

  8. Response of Moist Convection to Multi-scale Surface Flux Heterogeneity

    Science.gov (United States)

    Kang, S. L.; Ryu, J. H.

    2015-12-01

    We investigate response of moist convection to multi-scale feature of the spatial variation of surface sensible heat fluxes (SHF) in the afternoon evolution of the convective boundary layer (CBL), utilizing a mesoscale-domain large eddy simulation (LES) model. The multi-scale surface heterogeneity feature is analytically created as a function of the spectral slope in the wavelength range from a few tens of km to a few hundreds of m in the spectrum of surface SHF on a log-log scale. The response of moist convection to the κ-3 - slope (where κ is wavenumber) surface SHF field is compared with that to the κ-2 - slope surface, which has a relatively weak mesoscale feature, and the homogeneous κ0 - slope surface. Given the surface energy balance with a spatially uniform available energy, the prescribed SHF has a 180° phase lag with the latent heat flux (LHF) in a horizontal domain of (several tens of km)2. Thus, warmer (cooler) surface is relatively dry (moist). For all the cases, the same observation-based sounding is prescribed for the initial condition. For all the κ-3 - slope surface heterogeneity cases, early non-precipitating shallow clouds further develop into precipitating deep thunderstorms. But for all the κ-2 - slope cases, only shallow clouds develop. We compare the vertical profiles of domain-averaged fluxes and variances, and the contribution of the mesoscale and turbulence contributions to the fluxes and variances, between the κ-3 versus κ-2 slope cases. Also the cross-scale processes are investigated.

  9. Following the surface response of caffeine cocrystals to controlled humidity storage by atomic force microscopy.

    Science.gov (United States)

    Cassidy, A M C; Gardner, C E; Jones, W

    2009-09-08

    Active pharmaceutical ingredient (API) stability in solid state tablet formulation is frequently a function of the relative humidity (RH) environment in which the drug is stored. Caffeine is one such problematic API. Previously reported caffeine cocrystals, however, were found to offer increased resistance to caffeine hydrate formation. Here we report on the use of atomic force microscopy (AFM) to image the surface of two caffeine cocrystal systems to look for differences between the surface and bulk response of the cocrystal to storage in controlled humidity environments. Bulk responses have previously been assessed by powder X-ray diffraction. With AFM, pinning sites were identified at step edges on caffeine/oxalic acid, with these sites leading to non-uniform step movement on going from ambient to 0% RH. At RH >75%, areas of fresh crystal growth were seen on the cocrystal surface. In the case of caffeine/malonic acid the cocrystals were observed to absorb water anisotropically after storage at 75% RH for 2 days, affecting the surface topography of the cocrystal. These results show that AFM expands on the data gathered by bulk analytical techniques, such as powder X-ray diffraction, by providing localised surface information. This surface information may be important for better predicting API stability in isolation and at a solid state API-excipient interface.

  10. Electrolyte effects on the surface chemistry and cellular response of anodized titanium

    International Nuclear Information System (INIS)

    Ohtsu, Naofumi; Kozuka, Taro; Hirano, Mitsuhiro; Arai, Hirofumi

    2015-01-01

    Highlights: • Ti samples were anodized using various electrolytes. • Anodization decreased carbon adsorption, improving hydrophilicity. • Improved hydrophilicity led to improved cellular attachment. • Only one electrolyte showed any heteroatom incorporation into the TiO 2 layer. • Choice of electrolyte played no role on the effects of anodization. - Abstract: Anodic oxidation of titanium (Ti) material is used to enhance biocompatibility, yet the effects of various electrolytes on surface characteristics and cellular behavior have not been completely elucidated. To investigate this topic, oxide layers were produced on Ti substrates by anodizing them in aqueous electrolytes of (NH 4 ) 2 O·5B 2 O 3 , (NH 4 ) 2 SO 4 , or (NH 4 ) 3 PO 4 , after which their surface characteristics and cellular responses were examined. Overall, no surface differences between the electrolytes were visually observed. X-ray photoelectron spectroscopy (XPS) revealed that the anodized surfaces are composed of titanium dioxide (TiO 2 ), while incorporation from electrolyte was only observed for (NH 4 ) 3 PO 4 . Surface adsorption of carbon contaminants during sterilization was suppressed by anodization, leading to lower water contact angles. The attachment of MC3T3-E1 osteoblast-like cells was also improved by anodization, as evidenced by visibly enlarged pseudopods. This improved attachment performance is likely due to TiO 2 formation. Overall, electrolyte selection showed no effect on either surface chemistry or cellular response of Ti materials

  11. Do Aging and Tactile Noise Stimulation Affect Responses to Support Surface Translations in Healthy Adults?

    Directory of Open Access Journals (Sweden)

    Marius Dettmer

    2016-01-01

    Full Text Available Appropriate neuromuscular responses to support surface perturbations are crucial to prevent falls, but aging-related anatomical and physiological changes affect the appropriateness and efficiency of such responses. Low-level noise application to sensory receptors has shown to be effective for postural improvement in a variety of different balance tasks, but it is unknown whether this intervention may have value for improvement of corrective postural responses. Ten healthy younger and ten healthy older adults were exposed to sudden backward translations of the support surface. Low-level noise (mechanical vibration to the foot soles was added during random trials and temporal (response latency and spatial characteristics (maximum center-of-pressure excursion and anterior-posterior path length of postural responses were assessed. Mixed-model ANOVA was applied for analysis of postural response differences based on age and vibration condition. Age affected postural response characteristics, but older adults were well able to maintain balance when exposed to a postural perturbation. Low-level noise application did not affect any postural outcomes. Healthy aging affects some specific measures of postural stability, and in high-functioning older individuals, a low-level noise intervention may not be valuable. More research is needed to investigate if recurring fallers and neuropathy patients could benefit from the intervention in postural perturbation tasks.

  12. The specificity of targeted vaccines for APC surface molecules influences the immune response phenotype.

    Directory of Open Access Journals (Sweden)

    Gunnveig Grødeland

    Full Text Available Different diseases require different immune responses for efficient protection. Thus, prophylactic vaccines should prime the immune system for the particular type of response needed for protection against a given infectious agent. We have here tested fusion DNA vaccines which encode proteins that bivalently target influenza hemagglutinins (HA to different surface molecules on antigen presenting cells (APC. We demonstrate that targeting to MHC class II molecules predominantly induced an antibody/Th2 response, whereas targeting to CCR1/3/5 predominantly induced a CD8(+/Th1 T cell response. With respect to antibodies, the polarizing effect was even more pronounced upon intramuscular (i.m delivery as compared to intradermal (i.d. vaccination. Despite these differences in induced immune responses, both vaccines protected against a viral challenge with influenza H1N1. Substitution of HA with ovalbumin (OVA demonstrated that polarization of immune responses, as a consequence of APC targeting specificity, could be extended to other antigens. Taken together, the results demonstrate that vaccination can be tailor-made to induce a particular phenotype of adaptive immune responses by specifically targeting different surface molecules on APCs.

  13. pH and redox responsive polymer for antifouling surface coating

    International Nuclear Information System (INIS)

    Lee, Kang Seok; In, Insik; Park, Sung Young

    2014-01-01

    Graphical abstract: Dual responsive surface with highly fouling resistance with the formation of a pH-dependent benzoic imine and redox-sensitive disulfide bond has been developed using a catechol/benzoic acid conjugated polymer and disulfide containing amine end-capped Pluronic. - Highlights: • Stimuli-responsive antifouling surface was prepared by layer-by-layer method. • The surface contact angle showed responsive behavior via pH and redox environments. • Simply coated polymer completely prevented cell adhesion onto surfaces. - Abstract: A dual environmentally responsive polymer with a highly fouling-resistant surface has been developed using poly[(hydroxyethyl methacrylate-g-benzoic acid)-co-(dimethylaminoethyl methacrylate-g-2-chloro-3′, 4′-dihydroxyacetophenone)] [poly[(HEMA-BA)-co-(DMAEMA-CCDP)], P1] as a coating material. The redox-sensitive disulfide containing amine end-capped Pluronic [(Plu-S-S-NH 2 ), P2] was then introduced over the P1 surface via the formation of a pH-dependent benzoic imine bond, where the polyethylene glycol (PEG) acts as an antifouling agent. The successful adhesion of P1 and the deposition of P2 onto the P1-coated substrate were ascertained with X-ray photoelectron spectroscopy (XPS). In vitro cell adhesion followed by scanning electron microscopy (SEM) indicated an excellent antifouling nature of the P2 layer. Consequently, the reattachment of Hela cells was strongly observed when P2 layered on P1-coated substrates (P1–P2) was pretreated at lower pH and high redox conditions. The P1–P2 bilayer-coated substrate has exhibited a great advantage in its effective antifouling behaviors with well-tuned cell attachment and detachment

  14. pH and redox responsive polymer for antifouling surface coating

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kang Seok [Department of Chemical and Biological Engineering, Korea National University of Transportation, Chungju, 380-702 (Korea, Republic of); In, Insik, E-mail: in1@ut.ac.kr [Department of Polymer Science and Engineering, Korea National University of Transportation, Chungju, 380-702 (Korea, Republic of); Department of IT Convergence, Korea National University of Transportation, Chungju, 380-702 (Korea, Republic of); Park, Sung Young, E-mail: parkchem@ut.ac.kr [Department of Chemical and Biological Engineering, Korea National University of Transportation, Chungju, 380-702 (Korea, Republic of); Department of IT Convergence, Korea National University of Transportation, Chungju, 380-702 (Korea, Republic of)

    2014-09-15

    Graphical abstract: Dual responsive surface with highly fouling resistance with the formation of a pH-dependent benzoic imine and redox-sensitive disulfide bond has been developed using a catechol/benzoic acid conjugated polymer and disulfide containing amine end-capped Pluronic. - Highlights: • Stimuli-responsive antifouling surface was prepared by layer-by-layer method. • The surface contact angle showed responsive behavior via pH and redox environments. • Simply coated polymer completely prevented cell adhesion onto surfaces. - Abstract: A dual environmentally responsive polymer with a highly fouling-resistant surface has been developed using poly[(hydroxyethyl methacrylate-g-benzoic acid)-co-(dimethylaminoethyl methacrylate-g-2-chloro-3′, 4′-dihydroxyacetophenone)] [poly[(HEMA-BA)-co-(DMAEMA-CCDP)], P1] as a coating material. The redox-sensitive disulfide containing amine end-capped Pluronic [(Plu-S-S-NH{sub 2}), P2] was then introduced over the P1 surface via the formation of a pH-dependent benzoic imine bond, where the polyethylene glycol (PEG) acts as an antifouling agent. The successful adhesion of P1 and the deposition of P2 onto the P1-coated substrate were ascertained with X-ray photoelectron spectroscopy (XPS). In vitro cell adhesion followed by scanning electron microscopy (SEM) indicated an excellent antifouling nature of the P2 layer. Consequently, the reattachment of Hela cells was strongly observed when P2 layered on P1-coated substrates (P1–P2) was pretreated at lower pH and high redox conditions. The P1–P2 bilayer-coated substrate has exhibited a great advantage in its effective antifouling behaviors with well-tuned cell attachment and detachment.

  15. Proposal of a method for evaluating tsunami risk using response-surface methodology

    Science.gov (United States)

    Fukutani, Y.

    2017-12-01

    Information on probabilistic tsunami inundation hazards is needed to define and evaluate tsunami risk. Several methods for calculating these hazards have been proposed (e.g. Løvholt et al. (2012), Thio (2012), Fukutani et al. (2014), Goda et al. (2015)). However, these methods are inefficient, and their calculation cost is high, since they require multiple tsunami numerical simulations, therefore lacking versatility. In this study, we proposed a simpler method for tsunami risk evaluation using response-surface methodology. Kotani et al. (2016) proposed an evaluation method for the probabilistic distribution of tsunami wave-height using a response-surface methodology. We expanded their study and developed a probabilistic distribution of tsunami inundation depth. We set the depth (x1) and the slip (x2) of an earthquake fault as explanatory variables and tsunami inundation depth (y) as an object variable. Subsequently, tsunami risk could be evaluated by conducting a Monte Carlo simulation, assuming that the generation probability of an earthquake follows a Poisson distribution, the probability distribution of tsunami inundation depth follows the distribution derived from a response-surface, and the damage probability of a target follows a log normal distribution. We applied the proposed method to a wood building located on the coast of Tokyo Bay. We implemented a regression analysis based on the results of 25 tsunami numerical calculations and developed a response-surface, which was defined as y=ax1+bx2+c (a:0.2615, b:3.1763, c=-1.1802). We assumed proper probabilistic distribution for earthquake generation, inundation height, and vulnerability. Based on these probabilistic distributions, we conducted Monte Carlo simulations of 1,000,000 years. We clarified that the expected damage probability of the studied wood building is 22.5%, assuming that an earthquake occurs. The proposed method is therefore a useful and simple way to evaluate tsunami risk using a response-surface

  16. The effect of cultureware surfaces on functional and structural components of differentiated 3T3-L1 preadipocytes

    Czech Academy of Sciences Publication Activity Database

    Pavlíková, N.; Weiszenstein, M.; Pala, J.; Halada, Petr; Šeda, O.; Elkalaf, M.; Trnka, J.; Kovář, J.; Polak, J.

    2015-01-01

    Roč. 20, č. 5 (2015), s. 919-936 ISSN 1425-8153 Institutional support: RVO:61388971 Keywords : Cell culture * Proteomics * Cultureware surface Subject RIV: CE - Biochemistry Impact factor: 1.753, year: 2015

  17. Surface tensions of multi-component mixed inorganic/organic aqueous systems of atmospheric significance: measurements, model predictions and importance for cloud activation predictions

    Directory of Open Access Journals (Sweden)

    D. O. Topping

    2007-01-01

    Full Text Available In order to predict the physical properties of aerosol particles, it is necessary to adequately capture the behaviour of the ubiquitous complex organic components. One of the key properties which may affect this behaviour is the contribution of the organic components to the surface tension of aqueous particles in the moist atmosphere. Whilst the qualitative effect of organic compounds on solution surface tensions has been widely reported, our quantitative understanding on mixed organic and mixed inorganic/organic systems is limited. Furthermore, it is unclear whether models that exist in the literature can reproduce the surface tension variability for binary and higher order multi-component organic and mixed inorganic/organic systems of atmospheric significance. The current study aims to resolve both issues to some extent. Surface tensions of single and multiple solute aqueous solutions were measured and compared with predictions from a number of model treatments. On comparison with binary organic systems, two predictive models found in the literature provided a range of values resulting from sensitivity to calculations of pure component surface tensions. Results indicate that a fitted model can capture the variability of the measured data very well, producing the lowest average percentage deviation for all compounds studied. The performance of the other models varies with compound and choice of model parameters. The behaviour of ternary mixed inorganic/organic systems was unreliably captured by using a predictive scheme and this was dependent on the composition of the solutes present. For more atmospherically representative higher order systems, entirely predictive schemes performed poorly. It was found that use of the binary data in a relatively simple mixing rule, or modification of an existing thermodynamic model with parameters derived from binary data, was able to accurately capture the surface tension variation with concentration. Thus

  18. Engineering the temporal response of photoconductive photodetectors via selective introduction of surface trap states.

    Science.gov (United States)

    Konstantatos, Gerasimos; Levina, Larissa; Fischer, Armin; Sargent, Edward H

    2008-05-01

    Photoconductive photodetectors fabricated using simple solution-processing have recently been shown to exhibit high gains (>1000) and outstanding sensitivities ( D* > 10(13) Jones). One ostensible disadvantage of exploiting photoconductive gain is that the temporal response is limited by the release of carriers from trap states. Here we show that it is possible to introduce specific chemical species onto the surfaces of colloidal quantum dots to produce only a single, desired trap state having a carefully selected lifetime. In this way we demonstrate a device that exhibits an attractive photoconductive gain (>10) combined with a response time ( approximately 25 ms) useful in imaging. We achieve this by preserving a single surface species, lead sulfite, while eliminating lead sulfate and lead carboxylate. In doing so we preserve the outstanding sensitivity of these devices, achieving a specific detectivity of 10(12) Jones in the visible, while generating a temporal response suited to imaging applications.

  19. Calculation of the surface water pollution index in the evaluation of environmental component of product life cycle

    Directory of Open Access Journals (Sweden)

    Олег Аскольдович Проскурнин

    2015-05-01

    Full Text Available The assessment feasibility of the combined effect of the product life cycle on the environment is grounded. As an example, the pollution of surface waters at the production stage is considered in the article. A mechanism of ranking indicators of surface water pollution according to their importance is proposed. An algorithm for checking the consistency of the statistical expert judgment in determining weight coefficient for the indicators of pollution, based on the use of the concordance coefficient, is given

  20. Development of cookies made with cocoyam, fermented sorghum and germinated pigeon pea flour blends using response surface methodology.

    Science.gov (United States)

    Okpala, Laura C; Okoli, Eric C

    2014-10-01

    Cookies were produced from blends of cocoyam, fermented sorghum and germinated pigeon pea 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, crispness 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 sensory and protein quality with single, binary and ternary combinations of germinated pigeon pea, fermented sorghum and cocoyam flours. Results showed that BV and NPU of most of the cookies were above minimum acceptable levels. With the exception of cookies containing high levels of pigeon pea flour, cookies had acceptable sensory scores. Increase in pigeon pea flour resulted in increase in the BV and NPU. Regression equations suggested that the ternary blends produced the highest increase in all the sensory attributes (with the exception of colour).

  1. Computer program for post-flight evaluation of the control surface response for an attitude controlled missile

    Science.gov (United States)

    Knauber, R. N.

    1982-01-01

    A FORTRAN IV coded computer program is presented for post-flight analysis of a missile's control surface response. It includes preprocessing of digitized telemetry data for time lags, biases, non-linear calibration changes and filtering. Measurements include autopilot attitude rate and displacement gyro output and four control surface deflections. Simple first order lags are assumed for the pitch, yaw and roll axes of control. Each actuator is also assumed to be represented by a first order lag. Mixing of pitch, yaw and roll commands to four control surfaces is assumed. A pseudo-inverse technique is used to obtain the pitch, yaw and roll components from the four measured deflections. This program has been used for over 10 years on the NASA/SCOUT launch vehicle for post-flight analysis and was helpful in detecting incipient actuator stall due to excessive hinge moments. The program is currently set up for a CDC CYBER 175 computer system. It requires 34K words of memory and contains 675 cards. A sample problem presented herein including the optional plotting requires eleven (11) seconds of central processor time.

  2. Comparative acid-base properties of the surface of components of the CdTe-ZnS system in series of substitutional solid solutions and their analogs

    Science.gov (United States)

    Kirovskaya, I. A.; Kasatova, I. Yu.

    2011-07-01

    The acid-base properties of the surface of solid solutions and binary components of the CdTe-ZnS system are studied by hydrolytic adsorption, nonaqueous conductometric titration, mechanochemistry, IR spectroscopy, and Raman scattering spectroscopy. The strength, nature, and concentration of acid centers on the original surface and that exposed to CO are determined. The changes in acid-base properties in dependence on the composition of the system under investigation in the series of CdB6, ZnB6 analogs are studied.

  3. Fabrication of biomimetic resorption lacunae-like structure on titanium surface and its osteoblast responses

    Science.gov (United States)

    Huo, Fangjun; Guo, Weihua; Wu, Hao; Wang, Yueting; He, Gang; Xie, Li; Tian, Weidong

    2018-04-01

    Biomimetic specific surface structure could improve biological behaviors of specific cells and eventual tissue integration. Featuring titanium surface with structures resembling bone resorption lacunae (RL) can be a promising approach to improve the osteoblast responses and osseointegration of implants. As a most common used dental implant surface, sandblasting and acid etching (SLA) surface has micro-sized structures with dimensions similar to RL, but great differences exist when it comes to shape and contour. In this work, by anodizing titanium substrate in a novel HCOONa/CH3COONa electrolyte, RL-like crater structures were fabricated with highly similar size, shape and contour. Compared with SLA, it was much more similar to RL structure in shape and contour. Furthermore, through subsequent alkali-heat treatment, nano-sized structures that overlaid the whole surface were obtained, which further mimic undercuts features inside the RL. The as-prepared surface was consisted of crystalline titania and exhibited super-hydrophilicity with good stability. In vitro evaluation results showed that the surface could significantly improve adhesion, proliferation and differentiation of MG63 cells in comparison with SLA. This new method may be a promising candidate for biomimetic modification of titanium implant to promote osseointegration.

  4. Multidisciplinary Difficult Airway Course: An Essential Educational Component of a Hospital-Wide Difficult Airway Response Program.

    Science.gov (United States)

    Leeper, W Robert; Haut, Elliott R; Pandian, Vinciya; Nakka, Sajan; Dodd-O, Jeffrey; Bhatti, Nasir; Hunt, Elizabeth A; Saheed, Mustapha; Dalesio, Nicholas; Schiavi, Adam; Miller, Christina; Kirsch, Thomas D; Berkow, Lauren

    2018-04-05

    A hospital-wide difficult airway response team was developed in 2008 at The Johns Hopkins Hospital with three central pillars: operations, safety monitoring, and education. The objective of this study was to assess the outcomes of the educational pillar of the difficult airway response team program, known as the multidisciplinary difficult airway course (MDAC). The comprehensive, full-day MDAC involves trainees and staff from all provider groups who participate in airway management. The MDAC occurs within the Johns Hopkins Medicine Simulation Center approximately four times per year and uses a combination of didactic lectures, hands-on sessions, and high-fidelity simulation training. Participation in MDAC is the main intervention being investigated in this study. Data were collected prospectively using course evaluation survey with quantitative and qualitative components, and prepost course knowledge assessment multiple choice questions (MCQ). Outcomes include course evaluation scores and themes derived from qualitative assessments, and prepost course knowledge assessment MCQ scores. Tertiary care academic hospital center PARTICIPANTS: Students, residents, fellows, and practicing physicians from the departments of Surgery, Otolaryngology Head and Neck Surgery, Anesthesiology/Critical Care Medicine, and Emergency Medicine; advanced practice providers (nurse practitioners and physician assistants), nurse anesthetists, nurses, and respiratory therapists. Totally, 23 MDACs have been conducted, including 499 participants. Course evaluations were uniformly positive with mean score of 86.9 of 95 points. Qualitative responses suggest major value from high-fidelity simulation, the hands-on skill stations, and teamwork practice. MCQ scores demonstrated significant improvement: median (interquartile range) pre: 69% (60%-81%) vs post: 81% (72%-89%), p < 0.001. Implementation of a MDAC successfully disseminated principles and protocols to all airway providers. Demonstrable

  5. Proceedings of US/Japan Workshop (97FT5-06) on High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices

    International Nuclear Information System (INIS)

    Nygren, Richard; Kureczko, Diana

    1998-10-01

    The 1997 US-Japan Workshop on High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices was held at the Warwick Regis Hotel in San Francisco, California, on December 8-11, 1997. There were 53 presentations as well as discussions on technical issues and on planning for future collaborations, and 35 researchers from japan and the US participated in the workshop. Over the last few years, with the strong emphasis in the US on technology for ITER, there has been less work done in the US fusion program on basic plasma materials interaction and this change in emphasis workshops. The program this year emphasized activities that were not carried out under the ITER program and a new element this year in the US program was planning and some analysis on liquid surface concepts for advanced plasma facing components. The program included a ceremony to honor Professor Yamashina, who was retiring this year and a special presentation on his career

  6. An algorithm for hyperspectral remote sensing of aerosols: 2. Information content analysis for aerosol parameters and principal components of surface spectra

    Science.gov (United States)

    Hou, Weizhen; Wang, Jun; Xu, Xiaoguang; Reid, Jeffrey S.

    2017-05-01

    This paper describes the second part of a series of investigation to develop algorithms for simultaneous retrieval of aerosol parameters and surface reflectance from the future hyperspectral and geostationary satellite sensors such as Tropospheric Emissions: Monitoring of POllution (TEMPO). The information content in these hyperspectral measurements is analyzed for 6 principal components (PCs) of surface spectra and a total of 14 aerosol parameters that describe the columnar aerosol volume Vtotal, fine-mode aerosol volume fraction, and the size distribution and wavelength-dependent index of refraction in both coarse and fine mode aerosols. Forward simulations of atmospheric radiative transfer are conducted for 5 surface types (green vegetation, bare soil, rangeland, concrete and mixed surface case) and a wide range of aerosol mixtures. It is shown that the PCs of surface spectra in the atmospheric window channel could be derived from the top-of-the-atmosphere reflectance in the conditions of low aerosol optical depth (AOD ≤ 0.2 at 550 nm), with a relative error of 1%. With degree freedom for signal analysis and the sequential forward selection method, the common bands for different aerosol mixture types and surface types can be selected for aerosol retrieval. The first 20% of our selected bands accounts for more than 90% of information content for aerosols, and only 4 PCs are needed to reconstruct surface reflectance. However, the information content in these common bands from each TEMPO individual observation is insufficient for the simultaneous retrieval of surface's PC weight coefficients and multiple aerosol parameters (other than Vtotal). In contrast, with multiple observations for the same location from TEMPO in multiple consecutive days, 1-3 additional aerosol parameters could be retrieved. Consequently, a self-adjustable aerosol retrieval algorithm to account for surface types, AOD conditions, and multiple-consecutive observations is recommended to derive

  7. Analysis of factors controlling soil phosphorus loss with surface runoff in Huihe National Nature Reserve by principal component and path analysis methods.

    Science.gov (United States)

    He, Jing; Su, Derong; Lv, Shihai; Diao, Zhaoyan; Bu, He; Wo, Qiang

    2018-01-01

    Phosphorus (P) loss with surface runoff accounts for the P input to and acceleration of eutrophication of the freshwater. Many studies have focused on factors affecting P loss with surface runoff from soils, but rarely on the relationship among these factors. In the present study, rainfall simulation on P loss with surface runoff was conducted in Huihe National Nature Reserve, in Hulunbeier grassland, China, and the relationships between P loss with surface runoff, soil properties, and rainfall conditions were examined. Principal component analysis and path analysis were used to analyze the direct and indirect effects on P loss with surface runoff. The results showed that P loss with surface runoff was closely correlated with soil electrical conductivity, soil pH, soil Olsen P, soil total nitrogen (TN), soil total phosphorus (TP), and soil organic carbon (SOC). The main driving factors which influenced P loss with surface runoff were soil TN, soil pH, soil Olsen P, and soil water content. Path analysis and determination coefficient analysis indicated that the standard multiple regression equation for P loss with surface runoff and each main factor was Y = 7.429 - 0.439 soil TN - 6.834 soil pH + 1.721 soil Olsen-P + 0.183 soil water content (r = 0.487, p runoff. The effect of physical and chemical properties of undisturbed soils on P loss with surface runoff was discussed, and the soil water content and soil Olsen P were strongly positive influences on the P loss with surface runoff.

  8. Enhanced cell disruption strategy in the release of recombinant hepatitis B surface antigen from Pichia pastoris using response surface methodology

    Science.gov (United States)

    2012-01-01

    Background Cell disruption strategies by high pressure homogenizer for the release of recombinant Hepatitis B surface antigen (HBsAg) from Pichia pastoris expression cells were optimized using response surface methodology (RSM) based on the central composite design (CCD). The factors studied include number of passes, biomass concentration and pulse pressure. Polynomial models were used to correlate the above mentioned factors to project the cell disruption capability and specific protein release of HBsAg from P. pastoris cells. Results The proposed cell disruption strategy consisted of a number of passes set at 20 times, biomass concentration of 7.70 g/L of dry cell weight (DCW) and pulse pressure at 1,029 bar. The optimized cell disruption strategy was shown to increase cell disruption efficiency by 2-fold and 4-fold for specific protein release of HBsAg when compared to glass bead method yielding 75.68% cell disruption rate (CDR) and HBsAg concentration of 29.20 mg/L respectively. Conclusions The model equation generated from RSM on cell disruption of P. pastoris was found adequate to determine the significant factors and its interactions among the process variables and the optimum conditions in releasing HBsAg when validated against a glass bead cell disruption method. The findings from the study can open up a promising strategy for better recovery of HBsAg recombinant protein during downstream processing. PMID:23039947

  9. Proteomic Response of Pseudomonas aeruginosa PAO1 Adhering to Solid Surfaces

    Directory of Open Access Journals (Sweden)

    Morgan Guilbaud

    2017-08-01

    Full Text Available Pseudomonas aeruginosa is a pathogenic micro-organism responsible for many hospital-acquired infections. It is able to adhere to solid surfaces and develop an immobilized community or so-called biofilm. Many studies have been focusing on the use of specific materials to prevent the formation of these biofilms, but the reactivity of the bacteria in contact to surfaces remains unknown. The aim of this study was to evaluate the impact of the abiotic surface on the physiology of adherent bacteria. Three different materials, stainless steel (SS, glass (G, and polystyrene (PS that were relevant to industrial or medical environments were characterized at the physicochemical level in terms of their hydrophobicity and roughness. We showed that SS was moderately hydrophilic and rough, potentially containing crevices, G was hydrophilic and smooth while PS was hydrophobic and smooth. We further showed that P. aeruginosa cells were more likely able to adhere to SS and G rather than PS surfaces under our experimental conditions. The physiological response of P. aeruginosa when adhering to each of these materials was then evaluated by global proteomic analysis. The abundance of 70 proteins was shown to differ between the materials suggesting that their abundance was modified as a function of the material to which bacteria adhered. Our data lead to enabling the identification of abundance patterns that appeared to be specific to a given surface. Taken together, our data showed that P. aeruginosa is capable of sensing and responding to a surface probably via specific programmes to adapt its physiological response accordingly.

  10. Response surfaces and sensitivity analyses for an environmental model of dose calculations

    Energy Technology Data Exchange (ETDEWEB)

    Iooss, Bertrand [CEA Cadarache, DEN/DER/SESI/LCFR, 13108 Saint Paul lez Durance, Cedex (France)]. E-mail: bertrand.iooss@cea.fr; Van Dorpe, Francois [CEA Cadarache, DEN/DTN/SMTM/LMTE, 13108 Saint Paul lez Durance, Cedex (France); Devictor, Nicolas [CEA Cadarache, DEN/DER/SESI/LCFR, 13108 Saint Paul lez Durance, Cedex (France)

    2006-10-15

    A parametric sensitivity analysis is carried out on GASCON, a radiological impact software describing the radionuclides transfer to the man following a chronic gas release of a nuclear facility. An effective dose received by age group can thus be calculated according to a specific radionuclide and to the duration of the release. In this study, we are concerned by 18 output variables, each depending of approximately 50 uncertain input parameters. First, the generation of 1000 Monte-Carlo simulations allows us to calculate correlation coefficients between input parameters and output variables, which give a first overview of important factors. Response surfaces are then constructed in polynomial form, and used to predict system responses at reduced computation time cost; this response surface will be very useful for global sensitivity analysis where thousands of runs are required. Using the response surfaces, we calculate the total sensitivity indices of Sobol by the Monte-Carlo method. We demonstrate the application of this method to one site of study and to one reference group near the nuclear research Center of Cadarache (France), for two radionuclides: iodine 129 and uranium 238. It is thus shown that the most influential parameters are all related to the food chain of the goat's milk, in decreasing order of importance: dose coefficient 'effective ingestion', goat's milk ration of the individuals of the reference group, grass ration of the goat, dry deposition velocity and transfer factor to the goat's milk.

  11. Effect of geometry on the surface characteristics of steel components AISI 4140 nitrited by DC-pulsed plasma

    International Nuclear Information System (INIS)

    Calahonra, C; De Las Heras, E; De La Serena, F; Corengia, P; Ybarra, G; Svoboda, H

    2004-01-01

    Steel AISI 4140 pieces containing cylindrical pinholes with different diameters and depths were nitrited by plasma, in an atmosphere of 25% N 2 + 75% H 2 under a DC-pulsed glow discharge for 15 h. The samples were nitrited to study the influence of the sizes of the pinholes on the uniformity of the compound layer, on the depth of the zone of diffusion and on the surface and subsurface micro-hardness. The results showed that nitriding pieces with pinholes introduces variations in the electric parameters and modifies the uniformity of the coat of compounds formed, altering the mechanical properties of the surface and subsurface (CW)

  12. The Covalent Binding of Photosensitive Dyes to Monocrystalline Silicon Surface and Their Spectral Response

    Institute of Scientific and Technical Information of China (English)

    郭志新; 郝纪祥; 张祖训; 曹子祥

    1993-01-01

    A chemical method is proposed to bond photo-sensitive dyes directly to the surface of polished monocrystalline silicon. A methincyanine dye and a trimethincyanine dye have been bonded covalently onto silicon surface through Si—N bond, which are characterized by XPS technique and laser Raman spectra. Photovoltaic effect has been observed with the In/dye/n-Si sandwich devices composed of the dye-bonded n-Si wafers. Significant spectral response shows the characteristic absorptance maxima of the bonded dyes.

  13. 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...... microscopy, and X-ray photoelectron spectroscopy. The effects of nanocoating on proliferation, matrix formation and mineralization, and expression of genes (real-time PCR) related to osteoblast differentiation and activity were tested using human osteoblast-like SaOS-2 cells. It was shown that RG-I coatings...

  14. Mutations in GLDN, Encoding Gliomedin, a Critical Component of the Nodes of Ranvier, Are Responsible for Lethal Arthrogryposis.

    Science.gov (United States)

    Maluenda, Jérôme; Manso, Constance; Quevarec, Loic; Vivanti, Alexandre; Marguet, Florent; Gonzales, Marie; Guimiot, Fabien; Petit, Florence; Toutain, Annick; Whalen, Sandra; Grigorescu, Romulus; Coeslier, Anne Dieux; Gut, Marta; Gut, Ivo; Laquerrière, Annie; Devaux, Jérôme; Melki, Judith

    2016-10-06

    Arthrogryposis multiplex congenita (AMC) is a developmental condition characterized by multiple joint contractures resulting from reduced or absent fetal movements. Through linkage analysis, homozygosity mapping, and exome sequencing in four unrelated families affected by lethal AMC, we identified biallelic mutations in GLDN in the affected individuals. GLDN encodes gliomedin, a secreted cell adhesion molecule involved in the formation of the nodes of Ranvier. Transmission electron microscopy of the sciatic nerve from one of the affected individuals showed a marked lengthening defect of the nodes. The GLDN mutations found in the affected individuals abolish the cell surface localization of gliomedin and its interaction with its axonal partner, neurofascin-186 (NF186), in a cell-based assay. The axoglial contact between gliomedin and NF186 is essential for the initial clustering of Na + channels at developing nodes. These results indicate a major role of gliomedin in node formation and the development of the peripheral nervous system in humans. These data indicate that mutations of GLDN or CNTNAP1 (MIM: 616286), encoding essential components of the nodes of Ranvier and paranodes, respectively, lead to inherited nodopathies, a distinct disease entity among peripheral neuropathies. Copyright © 2016 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  15. SU-E-T-751: Three-Component Kinetic Model of Tumor Growth and Radiation Response for Stereotactic Radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Y; Dahlman, E; Leder, K; Hui, S [University of Minnesota, Minneapolis, MN (United States)

    2015-06-15

    Purpose: To develop and study a kinetic model of tumor growth and its response to stereotactic radiosurgery (SRS) by assuming that the cells in irradiated tumor volume were made of three types. Methods: A set of ordinary differential equations (ODEs) were derived for three types of cells and a tumor growth rate. It is assumed that the cells were composed of actively proliferating cells, lethally damaged-dividing cells, and non-dividing cells. We modeled the tumor volume growth with a time-dependent growth rate to simulate the saturation of growth. After SRS, the proliferating cells were permanently damaged and converted to the lethally damaged cells. The amount of damaged cells were estimated by the LQ-model. The damaged cells gradually stopped dividing/proliferating and died with a constant rate. The dead cells were cleared from their original location with a constant rate. The total tumor volume was the sum of the three components. The ODEs were numerically solved with appropriate initial conditions for a given dosage. The proposed model was used to model an animal experiment, for which the temporal change of a rhabdomyosarcoma tumor volume grown in a rat was measured with time resolution sufficient to test the model. Results: To fit the model to the experimental data, the following characteristics were needed with the model parameters. The α-value in the LQ-model was smaller than the commonly used value; furthermore, it decreased with increasing dose. At the same time, the tumor growth rate after SRS had to increase. Conclusions: The new 3-component model of tumor could simulate the experimental data very well. The current study suggested that the radiation sensitivity and the growth rate of the proliferating tumor cells may change after irradiation and it depended on the dosage used for SRS. These preliminary observations must be confirmed by future animal experiments.

  16. 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 Traditional abrasive techniques such as grinding and lapping have long been used in the surface conditioning of engineering materials. However, in the processing of hard and brittle materials like silicon nitride (Si(sub3)N(sub4)), machining...

  17. Response of plasma facing components in Tokamaks due to intense energy deposition using Particle-In-Cell (PIC) methods

    Science.gov (United States)

    Genco, Filippo

    Damage to plasma-facing components (PFC) due to various plasma instabilities is still a major concern for the successful development of fusion energy and represents a significant research obstacle in the community. It is of great importance to fully understand the behavior and lifetime expectancy of PFC under both low energy cycles during normal events and highly energetic events as disruptions, Edge-Localized Modes (ELM), Vertical Displacement Events (VDE), and Run-away electron (RE). The consequences of these high energetic dumps with energy fluxes ranging from 10 MJ/m2 up to 200 MJ/m 2 applied in very short periods (0.1 to 5 ms) can be catastrophic both for safety and economic reasons. Those phenomena can cause a) large temperature increase in the target material b) consequent melting, evaporation and erosion losses due to the extremely high heat fluxes c) possible structural damage and permanent degradation of the entire bulk material with probable burnout of the coolant tubes; d) plasma contamination, transport of target material into the chamber far from where it was originally picked. The modeling of off-normal events such as Disruptions and ELMs requires the simultaneous solution of three main problems along time: a) the heat transfer in the plasma facing component b) the interaction of the produced vapor from the surface with the incoming plasma particles c) the transport of the radiation produced in the vapor-plasma cloud. In addition the moving boundaries problem has to be considered and solved at the material surface. Considering the carbon divertor as target, the moving boundaries are two since for the given conditions, carbon doesn't melt: the plasma front and the moving eroded material surface. The current solution methods for this problem use finite differences and moving coordinates system based on the Crank-Nicholson method and Alternating Directions Implicit Method (ADI). Currently Particle-In-Cell (PIC) methods are widely used for solving

  18. Convergence of PASTA kinase and two-component signaling in response to cell wall stress in Enterococcus faecalis.

    Science.gov (United States)

    Kellogg, Stephanie L; Kristich, Christopher J

    2018-04-09

    Two common signal transduction mechanisms used by bacteria to sense and respond to changing environments are two-component systems (TCSs) and eukaryotic-like Ser/Thr kinases and phosphatases (eSTK/Ps). Enterococcus faecalis is a Gram-positive bacterium and serious opportunistic pathogen that relies on both a TCS and an eSTK/P pathway for intrinsic resistance to cell wall-targeting antibiotics. The TCS consists of a histidine kinase (CroS) and response regulator (CroR) that become activated upon exposure of cells to cell wall-targeting antibiotics, leading to modulation of gene expression. The eSTK/P pathway consists of a transmembrane kinase (IreK) and its cognate phosphatase (IreP), which act antagonistically to mediate antibiotic resistance through an unknown mechanism. Because both CroS/R and IreK/P contribute to enterococcal resistance towards cell wall-targeting antibiotics, we hypothesized these signaling systems are intertwined. To test this hypothesis, we analyzed CroR phosphorylation and CroS/R-dependent gene expression to probe the influence of IreK and IreP on CroS/R signaling. In addition, we analyzed the phosphorylation state of CroS which revealed IreK-dependent phosphorylation of a Thr residue important for CroS function. Our results are consistent with a model in which IreK positively influences CroR-dependent gene expression through phosphorylation of CroS to promote antimicrobial resistance in E. faecalis Importance Two-component signaling systems (TCSs) and eukaryotic-like Ser/Thr kinases (eSTKs) are used by bacteria to sense and adapt to changing environments. Understanding how these pathways are regulated to promote bacterial survival is critical for a more complete understanding of bacterial stress responses and physiology. The opportunistic pathogen Enterococcus faecalis relies on both a TCS (CroS/R) and an eSTK (IreK) for intrinsic resistance to cell wall-targeting antibiotics. We probed the relationship between CroS/R and IreK, revealing

  19. Investigation of Surface Treatments to Improve the Friction and Wear of Titanium Alloys for Diesel Engine Components

    Energy Technology Data Exchange (ETDEWEB)

    Blau, Peter J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Cooley, Kevin M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kirkham, Melanie J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bansal, Dinesh G. [Oak Ridge Associated Universities, TN (United States)

    2012-09-20

    This final report summarizes experimental and analytical work performed under an agreement between the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Office of Transportation Technologies, and UT-Battelle LLC. The project was directed by Jerry Gibbs, of the U.S. Department of Energy’s Propulsion Materials Program, with management by D. P. Stinton and J. A. Haynes of ORNL. Participants included Peter J. Blau (Principal Investigator), Kevin M. Cooley (senior technician), Melanie J. Kirkham (materials scientist) of the Materials Science and Technology Division or ORNL, and Dinesh G. Bansal, a post doctoral fellow employed by Oak Ridge Associated Universities (ORAU) and who, at the time of this writing, is an engineer with Cummins, Inc. This report covers a three-year effort that involved two stages. In the first stage, and after a review of the literature and discussions with surface treatment experts, a series of candidate alloys and surface treatments for titanium alloy (Ti-6Al-4V) was selected for initial screening. After pre-screening using an ASTM standard test method, the more promising surface treatments were tested in Phase 2 using a variable loading apparatus that was designed and built to simulate the changing load patterns in a typical connecting rod bearing. Information on load profiles from the literature was supplemented with the help of T.C. Chen and Howard Savage of Cummins, Inc. Considering the dynamic and evolving nature of materials technology, this report presents a snapshot of commercial and experimental bearing surface technologies for titanium alloys that were available during the period of this work. Undoubtedly, further improvements in surface engineering methods for titanium will evolve.

  20. OPTIMIZATION OF SURFACE RESISTIVITY AND RELATIVE PERMITTIVITY OF SILICONE RUBBER FOR HIGH VOLTAGE APPLICATION USING RESPONSE SURFACE METHODOLOGY

    Directory of Open Access Journals (Sweden)

    N.N. Ali

    2017-06-01

    Full Text Available Silicone Rubber (SiR is considered as one of the most established insulator in High Voltage (HV industry. SiR possess a great function ability such as its lighter weight, great heat resistance and substantial electrical insulation properties. Dynamic research were performed all around the world in order to explore the unique insulating behavior of SiR but very little are done on the optimization of SiR in term of their processing parameters and formulation. In this work, four materials and processing factors were introduced; A: Alumina Trihydrate (ATH, B: Dicumyl-Peroxide (DCP, C: mixing speed and D: mixing time in order to analyze its contribution towards improving the surface resistivity and relative permittivity of SIR rubber. The factors range were set based on prior screening and are defined as; ATH (10 – 50 pphr, Dicumyl Peroxide (0.50 -1.50 pphr, speed of mixer (40 – 70 rpm and mixing period (5 – 10 mins which were then varied accordingly to produce an overall 19 samples of SiR blends. The testing results were analyzed using statistical Design of Experiment (DOE by applying two level full factorial from Design Expert Software (v10 to discover the inter-correlation between the factors studied and benefaction of each factor in improving both surface resistivity and relative permittivity responses of produced SiR blends. The model analysis on surface resistivity shows the coefficient of determination R2 value of 88.72% while the one for relative permittivity shows R2 value of 82.34 %. Combination of both dependent variables had yielded an optimization suggestion for SiR formulation and processing strategy of ATH: 50 pphr, DCP: 0.50 pphr, mixing speed: 70 rpm and mixing period: 10 mins with the desirability level of 0.835. The optimized formulation had resulted in the production of SiR blend with the characteristic of surface resistivity of 1.02039x10^14 Ω/sq and relative permittivity of 4.0231, respectively. In conclusion, it can be

  1. Laminar boundary layer response to rotation of a finite diameter surface patch

    International Nuclear Information System (INIS)

    Klewicki, J.C.; Hill, R.B.

    2003-01-01

    The responses of the flat plate laminar boundary layer to perturbations generated by rotating a finite patch of the bounding surface are explored experimentally. The size of the surface patch was of the same order as the boundary layer thickness. The displacement thickness Reynolds number range of the boundary layers explored was 72-527. The rotation rates of the surface patch ranged from 2.14 to 62.8 s-1. Qualitative flow visualizations and quantitative molecular tagging velocimetry measurements revealed that rotation of a finite surface patch generates an asymmetric loop-like vortex. Significant features of this vortex include that, (i) the sign of the vorticity in the vortex head is opposite that of the boundary layer vorticity regardless of the sign of the input rotation, (ii) one leg of the vortex exhibits motion akin to solid body rotation while the other leg is best characterized as a spanwise shear layer, (iii) the vortex leg exhibiting near solid body rotation lifts more rapidly from the surface than the leg more like a shear layer, and (iv) the vortex leg exhibiting near solid body rotation always occurs on the side of the surface patch experiencing downstream motion. These asymmetries switch sides depending on the sign of the input rotation. The present results are interpreted and discussed relative to analytical solutions for infinite geometries. By way of analogy, plausible connections are drawn between the present results and the influences of wall normal vortices in turbulent boundary layer flows

  2. [Application of three compartment model and response surface model to clinical anesthesia using Microsoft Excel].

    Science.gov (United States)

    Abe, Eiji; Abe, Mari

    2011-08-01

    With the spread of total intravenous anesthesia, clinical pharmacology has become more important. We report Microsoft Excel file applying three compartment model and response surface model to clinical anesthesia. On the Microsoft Excel sheet, propofol, remifentanil and fentanyl effect-site concentrations are predicted (three compartment model), and probabilities of no response to prodding, shaking, surrogates of painful stimuli and laryngoscopy are calculated using predicted effect-site drug concentration. Time-dependent changes in these calculated values are shown graphically. Recent development in anesthetic drug interaction studies are remarkable, and its application to clinical anesthesia with this Excel file is simple and helpful for clinical anesthesia.

  3. [Concentrations and Component Profiles PAHs in Surface Soils and Wheat Grains from the Cornfields Close to the Steel Smelting Industry in Handan, Hebei Province].

    Science.gov (United States)

    Wu, Di; Wang, Yi-long; Liu, Wei-jian; Chen, Yuan-chen; Fu, Xiao-fang; Tao, Shu; Liu, Wen-xin

    2016-02-15

    In this study, paired surface soil and mature wheat grain samples were collected in the cornfields near the large Handan Steel Manufacturer; and the total concentrations and compositional profiles of the parent PAHs were measured, then the spatial distribution characteristics and correlation with total organic carbon fractions in soil were determined. Accordingly, a preliminary source identification was performed, and the association between PAHs in surface soil and wheat grain was briefly discussed. The median concentration of total PAHs in surface soils from the cornfields of Handan was 398.9 ng x g(-1) (ranged from 123.4 ng x g(-1) to 1626.4 ng x g(-1), where around 18% and 10% of all the studied soil samples were over the corresponding quality criteria for total PAHs and B [a] P in soils, respectively. The MMW and HMW species were the main components in the compositional profiles of surface soils. Based on the specific isomeric ratios of PAHs species, coal/biomass combustion and transportation fuel (tail gas) were the dominant mixed sources for the local PAHs emission. The fractions of surface soil TOC had significant positive correlations with the total PAHs and also with the individual components with different rings. In addition, the median concentration of total PAHs in wheat grains collected in the cornfields near the Handan Steel Manufacture was 27.0 ng x g(-1) (ranged from 19.0-34.0 ng x g(-1)). The levels in wheat grains were not high, and lower than the related hygienic standards of food proposed by EU and China. The LMW and MMW PAHs with 2 to 4 rings occupied a larger proportion, more than 84% of the total PAHs, which was largely different from the component profiles in surface soils. This situation suggested that the local sources of PAHs in wheat grains may originate not only from surface soil via root absorption and internal transportation, but also from ambient air through dry and wet deposition on the leaf surface (stoma).

  4. Final Report: Optimal Model Complexity in Geological Carbon Sequestration: A Response Surface Uncertainty Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ye [Univ. of Wyoming, Laramie, WY (United States)

    2018-01-17

    The critical component of a risk assessment study in evaluating GCS is an analysis of uncertainty in CO2 modeling. In such analyses, direct numerical simulation of CO2 flow and leakage requires many time-consuming model runs. Alternatively, analytical methods have been developed which allow fast and efficient estimation of CO2 storage and leakage, although restrictive assumptions on formation rock and fluid properties are employed. In this study, an intermediate approach is proposed based on the Design of Experiment and Response Surface methodology, which consists of using a limited number of numerical simulations to estimate a prediction outcome as a combination of the most influential uncertain site properties. The methodology can be implemented within a Monte Carlo framework to efficiently assess parameter and prediction uncertainty while honoring the accuracy of numerical simulations. The choice of the uncertain properties is flexible and can include geologic parameters that influence reservoir heterogeneity, engineering parameters that influence gas trapping and migration, and reactive parameters that influence the extent of fluid/rock reactions. The method was tested and verified on modeling long-term CO2 flow, non-isothermal heat transport, and CO2 dissolution storage by coupling two-phase flow with explicit miscibility calculation using an accurate equation of state that gives rise to convective mixing of formation brine variably saturated with CO2. All simulations were performed using three-dimensional high-resolution models including a target deep saline aquifer, overlying caprock, and a shallow aquifer. To evaluate the uncertainty in representing reservoir permeability, sediment hierarchy of a heterogeneous digital stratigraphy was mapped to create multiple irregularly shape stratigraphic models of decreasing geologic resolutions: heterogeneous (reference), lithofacies, depositional environment, and a (homogeneous) geologic formation. To ensure model

  5. Linking soil moisture balance and source-responsive models to estimate diffuse and preferential components of groundwater recharge

    Science.gov (United States)

    Cuthbert, M.O.; Mackay, R.; Nimmo, J.R.

    2012-01-01

    Results are presented of a detailed study into the vadose zone and shallow water table hydrodynamics of a field site in Shropshire, UK. A conceptual model is developed and tested using a range of numerical models, including a modified soil moisture balance model (SMBM) for estimating groundwater recharge in the presence of both diffuse and preferential flow components. Tensiometry reveals that the loamy sand topsoil wets up via macropore flow and subsequent redistribution of moisture into the soil matrix. Recharge does not occur until near-positive pressures are achieved at the top of the sandy glaciofluvial outwash material that underlies the topsoil, about 1 m above the water table. Once this occurs, very rapid water table rises follow. This threshold behaviour is attributed to the vertical discontinuity in the macropore system due to seasonal ploughing of the topsoil, and a lower permeability plough/iron pan restricting matrix flow between the topsoil and the lower outwash deposits. Although the wetting process in the topsoil is complex, a SMBM is shown to be effective in predicting the initiation of preferential flow from the base of the topsoil into the lower outwash horizon. The rapidity of the response at the water table and a