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Sample records for degraded wall paintings

  1. Typical Window, Interior Wall Paint Sequence, Wall Section, and Foundation ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Typical Window, Interior Wall Paint Sequence, Wall Section, and Foundation Sections - Civilian Conservation Corps (CCC) Camp NP-5-C, Barracks No. 5, CCC Camp Historic District at Chapin Mesa, Cortez, Montezuma County, CO

  2. Wall Paint Exposure Assessment Model (WPEM)

    EPA Pesticide Factsheets

    WPEM uses mathematical models developed from small chamber data to estimate the emissions of chemicals from oil-based (alkyd) and latex wall paint which is then combined with detailed use, workload and occupancy data to estimate user exposure.

  3. Nanoparticles for cultural heritage conservation: calcium and barium hydroxide nanoparticles for wall painting consolidation.

    PubMed

    Giorgi, Rodorico; Ambrosi, Moira; Toccafondi, Nicola; Baglioni, Piero

    2010-08-16

    Nanotechnology provides new concepts and materials for the consolidation and protection of wall paintings. In particular, humble calcium and barium hydroxide nanoparticles offer a versatile and highly efficient tool to combat the main degradation processes altering wall paintings. Clear example of the efficacy and potentiality of nanotechnology is represented by the conservation in situ of Maya wall paintings in the archaeological area in Calakmul (Mexico).

  4. Non-destructive mapping of dampness and salts in degraded wall paintings in hypogeous buildings: the case of St. Clement at mass fresco in St. Clement Basilica, Rome.

    PubMed

    Di Tullio, Valeria; Proietti, Noemi; Gobbino, Marco; Capitani, Donatella; Olmi, Roberto; Priori, Saverio; Riminesi, Cristiano; Giani, Elisabetta

    2010-03-01

    As is well known, the deterioration of wall paintings due to the capillary rise of water through the walls is a very widespread problem. In this paper, a study of microclimate monitoring, unilateral nuclear magnetic resonance (NMR), and evanescent-field dielectrometry (EFD) was applied to map non-destructively, in situ, and in a quantitative way the distribution of the moisture in an ancient deteriorated wall painting of the eleventh century. Both unilateral NMR and EFD are quite new, fully portable, and non-destructive techniques, and their combination is absolutely new. The approach reported here is proposed as a new analytical protocol to afford the problem of mapping, non-destructively, the moisture in a deteriorated wall painting in a hypogeous building such as that of the second level of St. Clement Basilica, Rome (Italy), where the use of IR thermography is impaired due to the environmental conditions, and the gravimetric tests are forbidden due to the preciousness of the artifact. The moisture distribution was mapped at different depths, from the very first layers of the painted film to a depth of 2 cm. It has also been shown how the map obtained in the first layers of the artwork is affected by the environmental conditions typical of a hypogeous building, whereas the maps obtained at higher depths are representative of the moisture due to the capillary rise of water from the ground. The quantitative analysis of the moisture was performed by calibrating NMR and EFD signals with purposely prepared specimens. This study may be applied before and after performing any intervention aimed at restoring and improving the state of conservation of this type of artwork and reducing the dampness or extracting salts (driven by the variation of moisture content) and monitoring the effectiveness of the performed interventions during the time. This protocol is applicable to any type of porous material.

  5. Pigment Degradation in Oil Paint Induced by Indoor Climate: Comparison of Visual and Computational Backscattered Electron Images.

    PubMed

    Keune, Katrien; Kramer, Rick P; Huijbregts, Zara; Schellen, Henk L; Stappers, Marc H L; van Eikema Hommes, Margriet H

    2016-04-01

    For the first time the degradation of lead white pigment in mature oil paint has been used as an internal marker for the degree of saponification and hence chemical degradation of oil paint. Computational image analysis of the backscattered electron images quantified the degree of the intact lead white pigment versus the nonpigmented and lead-rich areas (degraded lead white) in the paint layers. This new methodology was applied to a series of paint samples taken from four painted wall hangings (dated 1778), which makes it possible to study the influence of indoor climate on chemical degradation of aged oil paintings. The visual interpretation and computational image analysis of the backscattered electron images revealed clear trends. The highest degree of lead white degradation in the room was found in samples from the north wall close to the windows, whereas degradation diminished further away from the window. Lead white from the south wall was less degraded, but showed a similar trend as in the paintings on the north wall. These results imply a strong relationship between chemical degradation of paint and location of the paint in the room.

  6. Improving FTIR imaging speciation of organic compound residues or their degradation products in wall painting samples, by introducing a new thin section preparation strategy based on cyclododecane pre-treatment.

    PubMed

    Papliaka, Zoi Eirini; Vaccari, Lisa; Zanini, Franco; Sotiropoulou, Sophia

    2015-07-01

    Fourier transform infrared (FTIR) imaging in transmission mode, employing a bidimensional focal plane array (FPA) detector, was applied for the detection and spatially resolved chemical characterisation of organic compounds or their degradation products within the stratigraphy of a critical group of fragments, originating from prehistoric and roman wall paintings, containing a very low concentration of subsisted organic matter or its alteration products. Past analyses using attenuated total reflection (ATR) or reflection FTIR on polished cross sections failed to provide any evidence of any organic material assignable as binding medium of the original painting. In order to improve the method's performance, in the present study, a new method of sample preparation in thin section was developed. The procedure is based on the use of cyclododecane C12H24 as embedding material and a subsequent double-side polishing of the specimen. Such procedure provides samples to be studied in FTIR transmission mode without losing the information on the spatial distribution of the detected materials in the paint stratigraphy. For comparison purposes, the same samples were also studied after opening their stratigraphy with a diamond anvil cell. Both preparation techniques offered high-quality chemical imaging of the decay products of an organic substance, giving clues to the painting technique. In addition, the thin sections resulting from the cyclododecane pre-treatment offered more layer-specific data, as the layer thickness and order remained unaffected, whereas the samples resulting from compression within the diamond cell were slightly deformed; however, since thinner and more homogenous, they provided higher spectral quality in terms of S/N ratio. In summary, the present study illustrates the appropriateness of FTIR imaging in transmission mode associated with a new thin section preparation strategy to detect and localise very low-concentrated organic matter subjected to

  7. Unilateral NMR study of a XVI century wall painted

    NASA Astrophysics Data System (ADS)

    Proietti, N.; Capitani, D.; Rossi, E.; Cozzolino, S.; Segre, A. L.

    2007-06-01

    Wall paintings in the XVI century Serra Chapel in the "Chiesa di Nostra Signora del Sacro Cuore" Rome, have been studied using unilateral NMR. In order to map the distribution of moisture content in the wall painted, a large number of Hahn echo measurements, covering large areas of the wall painting were performed. Because the intensity of the Hahn echo is proportional to the amount of moisture in the area under study, the experimental data were transformed into 2D gradient colour maps which allowed an easy visualization of the moisture content of the wall. The state of conservation of the wall painting was monitored using T2 measurements specially with regards to outcropping salt.

  8. 4. LARGE MEETING ROOM, SOUTH WALL, FIREPLACE AND PAINTING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. LARGE MEETING ROOM, SOUTH WALL, FIREPLACE AND PAINTING - Penn School Historic District, Frissell Community House, SC Route 37, 1 mile South of Frogmore, St. Helena Island, Frogmore, Beaufort County, SC

  9. 5. MERCHANDISE BUILDING, BRIDGE, PAINT FACTORY, AND WALL PAPER MILL, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. MERCHANDISE BUILDING, BRIDGE, PAINT FACTORY, AND WALL PAPER MILL, VIEW TO NORTHEAST - Sears Roebuck & Company Mail Order Plant, Bounded by Lexington & Grenshaw Streets, Kedzie Avenue & Independence Boulevard, Chicago, Cook County, IL

  10. A study of smalt and red lead discolouration in Antiphonitis wall paintings in Cyprus

    NASA Astrophysics Data System (ADS)

    Sister Daniilia; Minopoulou, Elpida

    2009-08-01

    The present analytical study focuses on the degradation phenomena observed in fifteenth century wall paintings of the Christ Antiphonitis monastery in Cyprus. Examination of ten fragments by means of optical microscopy (OM), scanning electron microscopy (SEM/EDS), μRaman and FTIR spectroscopy revealed smalt discolouration and loss, and transformation of red lead from orange Pb3O4 to black PbO2. The chromatic changes have affected the aesthetic effect of the paintings insofar as these pigments were extensively used. The mechanisms of smalt weathering, i.e. leaching of alkali and formation of micro-cracks, are interpreted in relation to its chemical composition and to the aggressive environmental conditions. In addition, it is assumed that red lead degradation may have been induced not only by the effect of temperature, light and humidity but also by the presence of chlorine salts. These phenomena of pigment alteration and loss underline the unsuitability of smalt and minium on wall paintings, regardless of the painting technique ( fresco, fresco-secco, secco).

  11. Analysis of Roman wall paintings found in Verona.

    PubMed

    Mazzocchin, Gian Antonio; Rudello, Danilo; Murgia, Emanuela

    2007-09-01

    The present paper deals with the analysis of roman wall paintings fragments recovered from twelve buildings of Verona, Italy. The analytical techniques used were Optical Microscopy, Scanning Electron Microscopy (SEM) equipped with an EDS microanalysis detector, Xray powder diffraction (XRD) Fourier Transform infrared spectroscopy (FTIR) and Raman Spectroscopy. The wall preparation generally consisted of three layer: the pictorial layer, an intonachino layer of hydrated lime and a plaster one made of slaked lime and sand. The pigments found in the studied domus are different reflecting the taste and culture of Xa Regio of Italy but also the economical possibilities of the dominus and the building period.

  12. Investigating shoulder muscle loading and exerted forces during wall painting tasks: influence of gender, work height and paint tool design.

    PubMed

    Rosati, Patricia M; Chopp, Jaclyn N; Dickerson, Clark R

    2014-07-01

    The task of wall painting produces considerable risk to the workers, both male and female, primarily in the development of upper extremity musculoskeletal disorders. Insufficient information is currently available regarding the potential benefits of using different paint roller designs or the possible adverse effects of painting at different work heights. The aim of this study was to investigate the influence of gender, work height, and paint tool design on shoulder muscle activity and exerted forces during wall painting. Ten young adults, five male and five female, were recruited to perform simulated wall painting at three different work heights with three different paint roller designs while upper extremity muscle activity and horizontal push force were recorded. Results demonstrated that for female participants, significantly greater total average (p = 0.007) and integrated (p = 0.047) muscle activity was present while using the conventional and curly flex paint roller designs compared to the proposed design in which the load was distributed between both hands. Additionally, for both genders, the high working height imposed greater muscular demands compared to middle and low heights. These findings suggest that, if possible, avoid painting at extreme heights (low or high) and that for female painters, consider a roller that requires the use of two hands; this will reduce fatigue onset and subsequently mitigate potential musculoskeletal shoulder injury risks.

  13. Nuclear Weapon Yield Determination through Nano Indentation of Thermally Degraded Automobile Paint

    DTIC Science & Technology

    2011-03-01

    NUCLEAR WEAPON YIELD DETERMINATION THROUGH NANO INDENTATION OF THERMALLY DEGRADED AUTOMOBILE PAINT THESIS Michael Joseph Richards...NUCLEAR WEAPON YIELD DETERMINATION THROUGH NANO INDENATION OF THERMALLY DEGRADED AUTOMOBILE PAINT THESIS Presented to the Faculty Department...that has the potential to overcome these limitations relies on the change in automobile paint caused by the thermal pulse of the weapon. This work

  14. Analysis of pigments from Roman wall paintings found in Vicenza.

    PubMed

    Mazzocchin, G A; Agnoli, F; Mazzocchin, S; Colpo, I

    2003-11-12

    The analysis of about 60 samples of wall paintings was carried out using different chemicophysical techniques: optical microscopy, scanning electron microscopy (SEM) equipped with an EDS microanalysis detector, X-ray powder diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The identified pigments were cinnabar, hematite, red ochre, celadonite, cuprorivaite (Egyptian blue), yellow ochre, goethite and carbon. Only in one case some lead white was found instead. In general, the mortar preparation did not correspond to the complex structure suggested by Vitruvius (De Architectura), but it generally showed a porous layer, with crushed grains under the pigment layer. In certain cases two superposed pigment layers were found: yellow superimposed on both red and pink, black on pink, green on black.

  15. Improved Conjugate Gradient Bundle Adjustment of Dunhuang Wall Painting Images

    NASA Astrophysics Data System (ADS)

    Hu, K.; Huang, X.; You, H.

    2017-09-01

    Bundle adjustment with additional parameters is identified as a critical step for precise orthoimage generation and 3D reconstruction of Dunhuang wall paintings. Due to the introduction of self-calibration parameters and quasi-planar constraints, the structure of coefficient matrix of the reduced normal equation is banded-bordered, making the solving process of bundle adjustment complex. In this paper, Conjugate Gradient Bundle Adjustment (CGBA) method is deduced by calculus of variations. A preconditioning method based on improved incomplete Cholesky factorization is adopt to reduce the condition number of coefficient matrix, as well as to accelerate the iteration rate of CGBA. Both theoretical analysis and experimental results comparison with conventional method indicate that, the proposed method can effectively conquer the ill-conditioned problem of normal equation and improve the calculation efficiency of bundle adjustment with additional parameters considerably, while maintaining the actual accuracy.

  16. Degradation of nitrocellulose-based paint by Desulfovibrio desulfuricans ATCC 13541.

    PubMed

    Giacomucci, L; Toja, F; Sanmartín, P; Toniolo, L; Prieto, B; Villa, F; Cappitelli, F

    2012-09-01

    Nitrocellulose is one of the most commonly used compounds in ammunition and paint industries and its recalcitrance to degradation has a negative impact on human health and the environment. In this study the capability of Desulfovibrio desulfuricans ATCC 13541 to degrade nitrocellulose as binder in paint was assayed for the first time. Nitrocellulose-based paint degradation was followed by monitoring the variation in nitrate, nitrite and ammonium content in the culture medium using Ultraviolet-Visible spectroscopy. At the same time cell counts and ATP assay were performed to estimate bacterial density and activity in all samples. Infrared spectroscopy and colorimetric measurements of paint samples were performed to assess chemical and colour changes due to the microbial action. Microscope observations of nitrocellulose-based paint samples demonstrated the capability of the bacterium to adhere to the paint surface and change the paint adhesive characteristics. Finally, preliminary studies of nitrocellulose degradation pathway were conducted by assaying nitrate- and nitrite reductases activity in D. desulfuricans grown in presence or in absence of paint. We found that D. desulfuricans ATCC 13541 is able to transform nitrocellulose as paint binder and we hypothesised ammonification as degradation pathway. The results suggest that D. desulfuricans ATCC 13541 is a good candidate as a nitrocellulose-degrading bacterium.

  17. Characterization of pigments and ligands in a wall painting fragment from Liternum archaeological park (Italy).

    PubMed

    Corso, Gaetano; Gelzo, Monica; Chambery, Angela; Severino, Valeria; Di Maro, Antimo; Lomoriello, Filomena Schiano; D'Apolito, Oceania; Dello Russo, Antonio; Gargiulo, Patrizia; Piccioli, Ciro; Arcari, Paolo

    2012-11-01

    Spectroscopic and MS techniques were used to characterize the pigments and the composition of polar and nonpolar binders of a stray wall painting fragment from Liternum (Italy) archaeological excavation. X-ray fluorescence and diffraction analysis of the decorations indicated mainly the presence of calcite, quartz, hematite, cinnabar, and cuprorivaite. Infrared spectroscopy, GC coupled to flame-ionization detector, and MS analysis of the polar and nonpolar components extracted from paint layers from three different color regions revealed the presence of free amino acids, sugars, and fatty acids. Interestingly, LC-MS shotgun analysis of the red painting region showed the presence of αS1-casein of buffalo origin. Compared to our previous results from Pompeii's wall paintings, even though the Liternum painting mixture contained also binders of animal origin, the data strongly suggest that in both cases a tempera painting technique was utilized. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Nanomaterial containing wall paints can increase radon concentration in houses located in radon prone areas.

    PubMed

    Haghani, M; Mortazavi, S M J; Faghihi, R; Mehdizadeh, S; Moradgholi, J; Darvish, L; Fathi-Pour, E; Ansari, L; Ghanbar-Pour, M R

    2013-09-01

    Nowadays, extensive technological advancements have made it possible to use nanopaints which show exciting properties. In IR Iran excessive radon levels (up to 3700 Bq m-3) have been reported in homes located in radon prone areas. Over the past decades, concerns have been raised about the risk posed by residential radon exposure. This study aims at investigating the effect of using nanomaterial containing wall paints on radon concentration in homes. Two wooden model houses were used in this study. Soil samples from Ramsar high background radiation areas were used for simulating the situation of a typical house in radon-prone areas. Conventional water-soluble wall paint was used for painting the walls of the 1st house model; while the 2nd house model was painted with the same wall paint with montmorillonitenanoclay. Three days after sealing the house models, radon level was measured by using a portable radon survey meter. The mean radon level inside the 1st house model (conventional paint) was 515.3 ± 17.8 Bq/m(3) while the mean radon concentration in the 2nd house model (nano-painted house model) was 570.8 ± 18.5 Bq/m(3). The difference between these means was statistically significant (P<0.001). To the best of our knowledge, this study is the first investigation on the effect of nano-material containing wall paints on indoor radon concentrations.  It can be concluded that nano-material-containing wall paints should not be used in houses with wooden walls located in radon prone areas. Although the mechanism of this effect is not clearly known, decreased porosity in nano-paints might be a key factor in increasing the radon concentration in homes.

  19. Nanomaterial Containing Wall Paints Can Increase Radon Concentration in Houses Located in Radon Prone Areas

    PubMed Central

    Haghani, M.; Mortazavi, S. M. J.; Faghihi, R.; Mehdizadeh, S.; Moradgholi, J.; Darvish, L.; Fathi-Pour, E.; Ansari, L.; Ghanbar-pour, M. R.

    2013-01-01

    Background: Nowadays, extensive technological advancements have made it possible to use nanopaints which show exciting properties. In IR Iran excessive radon levels (up to 3700 Bq m–3) have been reported in homes located in radon prone areas. Over the past decades, concerns have been raised about the risk posed by residential radon exposure. Objective: This study aims at investigating the effect of using nanomaterial containing wall paints on radon concentration in homes. Methods: Two wooden model houses were used in this study. Soil samples from Ramsar high background radiation areas were used for simulating the situation of a typical house in radon-prone areas. Conventional water-soluble wall paint was used for painting the walls of the 1st house model; while the 2nd house model was painted with the same wall paint with montmorillonitenanoclay. Results: Three days after sealing the house models, radon level was measured by using a portable radon survey meter. The mean radon level inside the 1st house model (conventional paint) was 515.3 ± 17.8 Bq/m3 while the mean radon concentration in the 2nd house model (nano-painted house model) was 570.8 ± 18.5 Bq/m3. The difference between these means was statistically significant (P<0.001). Conclusion: To the best of our knowledge, this study is the first investigation on the effect of nano-material containing wall paints on indoor radon concentrations.  It can be concluded that nano-material-containing wall paints should not be used in houses with wooden walls located in radon prone areas. Although the mechanism of this effect is not clearly known, decreased porosity in nano-paints might be a key factor in increasing the radon concentration in homes. PMID:25505754

  20. Spectroscopic Investigation Leading to the Documentation of Three Post-Byzantine Wall Paintings.

    PubMed

    Lampakis, Dimitrios; Karapanagiotis, Ioannis; Katsibiri, Olga

    2017-01-01

    The main churches of three monasteries in Thessalia, Central Greece, were decorated with wall paintings in the post-Byzantine period. The main goal of the present study is to characterize the inorganic and organic materials present in the paint layers of areas that have been gilded. Optical microscopic examination was carried out on samples taken from the gilded decoration of the paintings to view their layer build-up. The combined use of micro Fourier transform infrared (FT-IR) and micro-Raman spectroscopy led to the detection of the pigments and the binding media used. The results from specimens taken from different wall paintings were compared with each other to observe their differences and similarities. The three investigated churches are believed to have been painted by the same iconographer, Tzortzis, who however has only been identified in only one of them. The comparison led to the conclusion that there are many similarities in the painting materials used and the general methodology adopted and, therefore, this study offers support to the belief that the mural paintings of the three monasteries could have been painted by the same iconographer. While not authenticating the two painting as being by Tzortzis, the results provide further critical material that is consistent with this attribution. However, this statement must be carefully considered because the pigments identified have been commonly and diffusely used in historic mural paintings.

  1. Fabrication and Characterization of Waterborne Multi-wall Carbon Nanotube Paints

    NASA Astrophysics Data System (ADS)

    Dowty, Heather; Wang, Chyi-Shan

    2005-04-01

    The fabrication of water-borne polyurethane nanocomposites containing multi-wall nanotubes has presented a significant technological challenge to those in the polymer community. Such conductive polyurethanes are of great interest to the paint and coatings industry for use in electrical grounding and shielding. Currently, these materials are formed by strong acidic reflux of the nanotubes and subsequent dispersal in the polymer matrix. This treatment can result in significant shortening of the tubes and degradation of the resulting mechanical and electrical transport properties. Here we present an alternate technique in which various conductive and non-conductive water-soluble polymers are physi-adsorbed to the surface of the nanotube. These interactions with the nanotubes result in highly uniform suspensions of water-based urethane coatings and bulk materials. We will examine the polymer chemistry and morphologies of these nanostructured materials and the resulting thermal, electrical and mechanical properties.

  2. Determination of the method of construction of 1650 B.C. wall paintings.

    PubMed

    Papaodysseus, Constantin; Fragoulis, Dimitrios K; Panagopoulos, Mihalis; Panagopoulos, Thanasis; Rousopoulos, Panayiotis; Exarhos, Mihalis; Skembris, Angelos

    2006-09-01

    In this paper, a methodology of general applicability is presented for answering the question if an artist used a number of archetypes to draw a painting or if he drew it freehand. In fact, the contour line parts of the drawn objects that potentially correspond to archetypes are initially spotted. Subsequently, the exact form of these archetypes and their appearance throughout the painting is determined. The method has been applied to celebrated Thera Late Bronze Age wall paintings with full success. It has been demonstrated that the artist or group of artists has used seven geometrical archetypes and seven corresponding well-constructed stencils (four hyperbolae, two ellipses, and one Archimedes' spiral) to draw the wall painting "Gathering of Crocus" in 1650 B.C. This method of drawing seems to be unique in the history of arts and of great importance for archaeology, and the history of mathematics and sciences, as well.

  3. Degradation of azurite in mural paintings: distribution of copper carbonate, chlorides and oxalates by SRFTIR

    NASA Astrophysics Data System (ADS)

    Lluveras, A.; Boularand, S.; Andreotti, A.; Vendrell-Saz, M.

    2010-05-01

    This article illustrates the analysis by synchrotron micro-analytical techniques of an azurite painting presenting greenish chromatic degradation. The challenge of the experiments was to obtain the spatial distribution of the degradation products of azurite. Copper hydroxychlorides, carbonates and copper oxalates have been mapped by SR FTIR imaging of cross sections in transmission mode. To complement the information, Py/GC/MS and GC/MS techniques were applied in order to characterize the binding media and organic materials present as well as their degradation products. Results contribute to a better understanding of the decay of blue areas in ancient paintings not only from the particular point of view of azurite weathering, but also by adding information regarding the oxalates’ formation and their distribution in painting samples. Synchrotron radiation demonstrates its capability for the mapping in painting cross sections.

  4. Pigments with or without organic binder? A survey of wall painting techniques during Antiquity

    SciTech Connect

    Walter, P.

    1996-01-01

    The identification of ancient artistic techniques is based on laboratory studies and, for historical cases, also on literary sources. An analytical approach using the techniques of physical chemistry reveals the technical expertise of the artists, right at the dawn of art. In the case of prehistoric parietal art, we show that the artists prepared their pigments with different ground and mixed minerals. They applied their material onto the wall and the particles remained embedded in the superficial calcite layer. Later, the prehistoric people prepared a real paint with the proper pigment, an extender and an organic binder to fix the paint on the wall. During Antiquity, new techniques appear. The paint is applied to the natural or artificial wall and is executed, either directly or on a previously applied plaster. The aim of this paper is to describe the evolution of the techniques. The underlying chemistry provides some interesting clues on the technical choices. {copyright} {ital 1996 American Institute of Physics.}

  5. Infrared spectroscopic and chemometric approach for identifying binding medium in Sukias mansion's wall paintings.

    PubMed

    Haghighi, Zahra; Karimy, Amir-Hossein; Karami, Farshad; Bagheri Garmarudi, Amir; Khanmohammadi, Mohammadreza

    2015-11-11

    This paper addresses the application of infrared spectroscopy in combination with chemometrics to identify wall painting's binding medium while employing pattern recognition techniques to process FTIR data-set of complex samples. In this regard, based on the historical documents and previous researches, firstly 56 standard samples were prepared to represent strata of Persian wall paintings in the Safavid period in addition to real historic samples from the case study; Sukias mansion. Then, each sample was analysed by the means of FTIR and chemometrics. Finally, SIMCA was applied to the whole region of studied IR spectra which predicted egg yolk as the binding medium of Sukias mansion samples.

  6. Investigating the Photocatalytic Degradation of Oil Paint using ATR-IR and AFM-IR.

    PubMed

    Morsch, Suzanne; van Driel, Birgit A; van den Berg, Klaas Jan; Dik, Joris

    2017-03-22

    As linseed oil has a longstanding and continuing history of use as a binder in artistic paints, developing an understanding of its degradation mechanism is critical to conservation efforts. At present, little can be done to detect the early stages of oil paint deterioration due to the complex chemical composition of degrading paints. In this work, we use advanced infrared analysis techniques to investigate the UV-induced deterioration of model linseed oil paints in detail. Subdiffraction limit infrared analysis (AFM-IR) is applied to identify and map accelerated degradation in the presence of two different grades of titanium white pigment particles (rutile or anatase TiO2). Differentiation between the degradation of these two formulations demonstrates the sensitivity of this approach. The identification of characteristic peaks and transient species residing at the paint surface allows infrared absorbance peaks related to degradation deeper in the film to be extricated from conventional ATR-FTIR spectra, potentially opening up a new approach to degradation monitoring.

  7. Potential for atmospheric-driven lead paint degradation in the South Coast Air Basin of California.

    PubMed

    Cohan, Alexander J; Edwards, Rufus D; Kleinman, Michael T; Dabdub, Donald

    2009-12-01

    Exposure to lead in paint or lead residues in house dust and soil is one of the leading environmental risks to the health of children in the United States. Components of photochemical smog can increase the degradation of binders in lead paint, leading to increased release of lead pigment granules to hands in surface contact or for deposition in house dust and soil. This study uses photochemical air quality modeling to map areas susceptible to increased lead paint degradation as a result of photochemical atmospheric pollutants to prioritize areas of concern. Typical air quality episodes in the South Coast Air Basin of California (SoCAB) are modeled for the 1970s, 1980s, and 1990s. Results indicate that large areas of the SoCAB were susceptible to atmospheric-driven accelerated lead paint degradation. Inner city urban areas from central Los Angeles to Azusa and most of Orange County had the highest susceptibility to accelerated lead paint degradation, followed by inland locations near the San Bernardino Mountains. This study identifies photochemical oxidant gases as contributors to greater lead release from indoor painted surfaces in urban areas.

  8. Radiation Induced Degradation of White Thermal Control Paint

    NASA Technical Reports Server (NTRS)

    Edwards, D. L.; Zwiener, J. M.; Wertz, G. E.; Vaughn, Jason A.; Kamenetzky, Rachel R.; Finckenor, M. M.; Meshishnek, M. J.

    1999-01-01

    This paper details a comparison analysis of the zinc-oxide pigmented white thermal control paints Z-93 and Z-93P. Both paints were simultaneously exposed to combined space environmental effects and analyzed using an in-vacuo reflectance technique. The dose applied to the paints was approximately equivalent to 5 yr in a geosynchronous orbit. This comparison analysis showed that Z-93P is an acceptable substitute for Z-93. Irradiated samples of Z-93 and Z-93P were subjected to additional exposures of ultraviolet (UV) radiation and analyzed using the in-vacuo reflectance technique to investigate UV activated reflectance recovery. Both samples showed minimal UV activated reflectance recovery after an additional 190 equivalent Sun hour (ESH) exposure. Reflectance response utilizing nitrogen as a repressurizing gas instead of air was also investigated. This investigation found the rates of reflectance recovery when repressurized with nitrogen are slower than when repressurized with air.

  9. Radiation Induced Degradation of White Thermal Control Paint

    NASA Technical Reports Server (NTRS)

    Edwards, D. L.; Zwiener, J. M.; Wertz, G. E.; Vaughn, Jason A.; Kamenetzky, Rachel R.; Finckenor, M. M.; Meshishnek, M. J.

    1998-01-01

    This paper details a comparison analysis of the zinc-oxide pigmented white thermal control paints Z-93 and Z-93P. Both paints were simultaneously exposed to combined space environmental effects and analyzed using an in-vacuo reflectance technique. The dose applied to the paints was approximately equivalent to 5 yr in a geosynchronous orbit. This comparison analysis showed that Z-93P is an acceptable substitute for Z-93. Irradiated samples of Z-93 and Z-93P were subjected to additional exposures of ultraviolet (UV) radiation and analyzed using the in-vacuo reflectance technique to investigate UV activated reflectance recovery. Both samples showed minimal UV activated reflectance recovery after an additional 190 equivalent Sun hour (ESH) exposure. Reflectance response utilizing nitrogen as a repressurizing gas instead of air was also investigated. This investigation found the rates of reflectance recovery when repressurized with nitrogen are slower than when repressurized with air.

  10. Radiation Induced Degradation of White Thermal Control Paint

    NASA Technical Reports Server (NTRS)

    Edwards, D. L.; Zwiener, J. M.; Wertz, G. E.; Vaughn, J. A.; Kamenetzky, R. R.; Finckenor, M. M.; Meshishnek, M. J.

    1998-01-01

    This paper details a comparison analysis of the Zinc Oxide pigmented white thermal control paints Z-93 and Z-93P. Both paints were simultaneously exposed to combined space environmental effects and analyzed using an in-vacuum reflectance technique. The dose applied to the paints was approximately equivalent to 5 years in a geosynchronous orbit. This comparison analysis showed that Z-93P is an acceptable substitute for Z-93. Irradiated samples of Z-93 and Z-93P were subjected to additional exposures of ultraviolet (UV) radiation and analyzed using the in-vacuum reflectance technique to investigate UV activated reflectance recovery. Both samples showed minimal UV activated reflectanc6 recovery after an additional 190 Equivalent Sun Hour (ESH) exposure. Reflectance response utilizing nitrogen as a repressurizing gas instead of air was also investigated. This investigation found the rates of reflectance recovery when repressurized with nitrogen are slower than when repressurized with air.

  11. Determination of early warning signs for photocatalytic degradation of titanium white oil paints by means of surface analysis

    NASA Astrophysics Data System (ADS)

    van Driel, B. A.; Wezendonk, T. A.; van den Berg, K. J.; Kooyman, P. J.; Gascon, J.; Dik, J.

    2017-02-01

    Titanium white (TiO2) has been widely used as a pigment in the 20th century. However, its most photocatalytic form (anatase) can cause severe degradation of the oil paint in which it is contained. UV light initiates TiO2-photocatalyzed processes in the paint film, degrading the oil binder into volatile components resulting in chalking of the paint. This will eventually lead to severe changes in the appearance of a painting. To date, limited examples of degraded works of art containing titanium white are known due to the relatively short existence of the paintings in question and the slow progress of the degradation process. However, UV light will inevitably cause degradation of paint in works of art containing photocatalytic titanium white. In this work, a method to detect early warning signs of photocatalytic degradation of unvarnished oil paint is proposed, using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Consequently, a four-stage degradation model was developed through in-depth study of TiO2-containing paint films in various stages of degradation. The XPS surface analysis proved very valuable for detecting early warning signs of paint degradation, whereas the AFM results provide additional confirmation and are in good agreement with bulk gloss reduction.

  12. Determination of early warning signs for photocatalytic degradation of titanium white oil paints by means of surface analysis.

    PubMed

    van Driel, B A; Wezendonk, T A; van den Berg, K J; Kooyman, P J; Gascon, J; Dik, J

    2017-02-05

    Titanium white (TiO2) has been widely used as a pigment in the 20th century. However, its most photocatalytic form (anatase) can cause severe degradation of the oil paint in which it is contained. UV light initiates TiO2-photocatalyzed processes in the paint film, degrading the oil binder into volatile components resulting in chalking of the paint. This will eventually lead to severe changes in the appearance of a painting. To date, limited examples of degraded works of art containing titanium white are known due to the relatively short existence of the paintings in question and the slow progress of the degradation process. However, UV light will inevitably cause degradation of paint in works of art containing photocatalytic titanium white. In this work, a method to detect early warning signs of photocatalytic degradation of unvarnished oil paint is proposed, using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Consequently, a four-stage degradation model was developed through in-depth study of TiO2-containing paint films in various stages of degradation. The XPS surface analysis proved very valuable for detecting early warning signs of paint degradation, whereas the AFM results provide additional confirmation and are in good agreement with bulk gloss reduction. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Nondestructive Raman investigation on wall paintings at Sala Vaccarini in Catania (Sicily)

    NASA Astrophysics Data System (ADS)

    Barone, Germana; Bersani, Danilo; Coccato, Alessia; Lauwers, Debbie; Mazzoleni, Paolo; Raneri, Simona; Vandenabeele, Peter; Manzini, Davide; Agostino, Giuseppe; Neri, Nicola Francesco

    2016-09-01

    In this work, the results of a Raman campaign for studying seventeenth-century Sicilian frescoes, by using two portable Raman systems, equipped with different excitation sources (785 and 1064 nm), are proposed. The measurements were performed with the aim to provide an in situ diagnostic analysis of the wall paintings (in terms of colorants and preparation layer) and to support the conservators in the framework of the ongoing restoration. The combined use of the two Raman spectrometers has given a complete overview on the artist palette and on the state of preservation of frescoes, also informing us about the technique employed by the painter. Natural pigments as hematite, vermillion, goethite, lead red, lead white and carbon-based black pigments have been identified. Additionally, the application of a transitional Romanesque-Renaissance frescoes method has been noticed by the systematic combined presence of calcite and gypsum in the substrate. Finally, the analyses have highlighted the presence of degradation products, mainly related to alteration of lead-based pigments.

  14. Evaluation of Tritium Behavior in the Epoxy Painted Concrete Wall of ITER Hot Cell

    SciTech Connect

    Nakamura, Hirofumi; Hayashi, Takumi; Kobayashi, Kazuhiro; Nishi, Masataka

    2005-07-15

    Tritium behavior released in the ITER hot cell has been investigated numerically using a combined analytical methods of a tritium transport analysis in the multi-layer wall (concrete and epoxy paint) with the one dimensional diffusion model and a tritium concentration analysis in the hot cell with the complete mixing model by the ventilation. As the results, it is revealed that tritium concentration decay and permeation issues are not serious problem in a viewpoint of safety, since it is expected that tritium concentration in the hot cell decrease rapidly within several days just after removing the tritium release source, and tritium permeation through the epoxy painted concrete wall will be negligible as long as the averaged realistic diffusion coefficient is ensured in the concrete wall. It is also revealed that the epoxy paint on the concrete wall prevents the tritium inventory increase in the concrete wall greatly (two orders of magnitudes), but still, the inventory in the wall is estimated to reach about 0.1 PBq for 20 years operation.

  15. OCT assessment of aortic wall degradation for surgical guidance

    NASA Astrophysics Data System (ADS)

    Real, E.; Val-Bernal, J. F.; Pontón, A.; Calvo Díez, M.; Mayorga, M.; Revuelta, J. M.; López-Higuera, J. M.; Conde, O. M.

    2014-05-01

    The degradation of the wall in large cardiovascular vessels, such as the aorta artery, induces weakness in the vessel that can lead to the formation of aneurysms and the rupture of the vessel. Characterization of the wall integrity is assessed by OCT for future intraoperative assistance in aneurysm graft surgery interventions. Optical Coherence Tomography (OCT) provides cross sectional images of the wall of the aortic media layer. Wall degradations appear as spatial anomalies in the reflectivity profile through the wall thickness. Wall degradation assessment is proposed by automatic identification and dimensioning of these anomalies within the homogeneous surrounding tissue.

  16. New highlights on degradation process of verdigris from easel paintings

    NASA Astrophysics Data System (ADS)

    Santoro, Carlotta; Zarkout, Karim; Le Hô, Anne-Solenn; Mirambet, François; Gourier, Didier; Binet, Laurent; Pagès-Camagna, Sandrine; Reguer, Solenn; Mirabaud, Sigrid; Le Du, Yann; Griesmar, Pascal; Lubin-Germain, Nadège; Menu, Michel

    2014-03-01

    Verdigris is a green copper organometallic pigment, widely used in paintings during the fifteenth and sixteenth centuries. With ageing, chromatic modifications like browning or darkening can be observed on those green painted layers. An original but crucial approach has been developed based on the characterization of a reference neutral verdigris pigment—anhydrous copper acetate—and model samples, made of verdigris and linseed oil. Samples have undergone artificial ageing (temperature, light) to reproduce the color change effect. They were analysed before and after accelerated ageing tests by a complementary set of classical techniques: colorimetry, electron paramagnetic resonance, X-ray absorption spectroscopy, and UV-visible absorption. Our experiments revealed that the incorporation of the verdigris pigment in linseed oil induces a transformation of the copper acetate bimetallic structure, with the formation of monomeric species. These monomers, however, are not directly responsible for the darkening. The chromatic alteration seems instead linked to the transient formation of Cu(I) in the copper complexes of the pigment/oil system. This formation could be initiated by ambient light absorption through ligand-to-metal charge transfer, which favors the decarboxylation of the copper complexes leading to the reduction of Cu(II) into Cu(I). Moreover, dioxygen can react with partially decarboxylated dimers to form peroxy-Cu dimer complexes that can be responsible for the darkening.

  17. Hydroxide nanoparticles for cultural heritage: consolidation and protection of wall paintings and carbonate materials.

    PubMed

    Chelazzi, David; Poggi, Giovanna; Jaidar, Yareli; Toccafondi, Nicola; Giorgi, Rodorico; Baglioni, Piero

    2013-02-15

    Colloids and Material Science are nowadays providing innovative and effective technological solutions in a wide range of applicative fields. In the last decade, nanomaterials have been specifically designed to ensure the long-term restoration and preservation of movable and immovable artworks. The main tasks to address by conservation scientists concern the cleaning, the deacidification and the consolidation of different kinds of artistic substrates. The aim of the present contribution is to provide an up-to-date overview on the synthesis and preparation of colloidal systems tailored to the consolidation and protection of wall paintings, plasters and stones, highlighting the most recent improvements. Two case studies, widely representative of typical consolidation problems, are presented, i.e. the preservation of wall paintings belonging to a Mesoamerican archeological site and the consolidation of two Italian Renaissance buildings.

  18. Optimization in differentiable manifolds in order to determine the method of construction of prehistoric wall paintings.

    PubMed

    Arabadjis, Dimitris; Rousopoulos, Panayiotis; Papaodysseus, Constantin; Exarhos, Michalis; Panagopoulos, Michail; Papazoglou-Manioudaki, Lena

    2011-11-01

    In this paper, a general methodology is introduced for the determination of potential prototype curves used for the drawing of prehistoric wall paintings. The approach includes 1) preprocessing of the wall-paintings contours to properly partition them, according to their curvature, 2) choice of prototype curves families, 3) analysis and optimization in 4-manifold for a first estimation of the form of these prototypes, 4) clustering of the contour parts and the prototypes to determine a minimal number of potential guides, and 5) further optimization in 4-manifold, applied to each cluster separately, in order to determine the exact functional form of the potential guides, together with the corresponding drawn contour parts. The methodology introduced simultaneously deals with two problems: 1) the arbitrariness in data-points orientation and 2) the determination of one proper form for a prototype curve that optimally fits the corresponding contour data. Arbitrariness in orientation has been dealt with a novel curvature based error, while the proper forms of curve prototypes have been exhaustively determined by embedding curvature deformations of the prototypes into 4-manifolds. Application of this methodology to celebrated wall paintings excavated at Tyrins, Greece, and the Greek island of Thera manifests that it is highly probable that these wall paintings were drawn by means of geometric guides that correspond to linear spirals and hyperbolae. These geometric forms fit the drawings’ lines with an exceptionally low average error, less than 0.39 mm. Hence, the approach suggests the existence of accurate realizations of complicated geometric entities more than 1,000 years before their axiomatic formulation in the Classical Ages.

  19. Use of different spectroscopic techniques in the analysis of Roman age wall paintings.

    PubMed

    Agnoli, Francesca; Calliari, Irene; Mazzocchin, Gian-Antonio

    2007-01-01

    In this paper the analysis of samples of Roman age wall paintings coming from: Pordenone, Vicenza and Verona is carried out by using three different techniques: energy dispersive x-rays spectroscopy (EDS), x-rays fluorescence (XRF) and proton induced x-rays emission (PIXE). The features of the three spectroscopic techniques in the analysis of samples of archaeological interest are discussed. The studied pigments were: cinnabar, yellow ochre, green earth, Egyptian blue and carbon black.

  20. Scientific evaluation of wall paintings from Bunesti Evangelical Church, Brasov county

    NASA Astrophysics Data System (ADS)

    Baciu, Annamaria; MǎruÅ£oiu, Constantin; Bibire, Cristina; Vornicu, Nicoleta; Dreve, Simina

    2013-11-01

    Evangelical Church in the village Bunesti, Brasov county, is part of the fortified churches built since the XIV century at the south-eastern territory of Transylvania. Developed by addition in several stages during centuries, the church begun as Catholic chapel, then that was amplified in the sixteenth century, when Reform was adopted by the Saxon communities. In that period the building was extended in length and height and the catholic specific iconographic decorations were cancelled by covering with different layers of plaster and paint. The campaign of introducing in touristic circuit of old Saxon fortified churches generated, in terms of maintenance and renovations undertaken, the discovery of significant wall paintings, as treasures to be rescued and put into value. Our present efforts are focused on scientific evaluation of mural paintings found in Evangelical Church from Bunesti, by XRF and specific analysis performed on 10 different samples of mural paintings, completing visual and artistic analysis in order to establish the strategies for their recovering and preservation.

  1. Byzantine wall paintings from Kastoria, northern Greece: Spectroscopic study of pigments and efflorescing salts

    NASA Astrophysics Data System (ADS)

    Iordanidis, Andreas; Garcia-Guinea, Javier; Strati, Aggeliki; Gkimourtzina, Amalia; Papoulidou, Androniki

    2011-02-01

    This study concerns the investigation of pigments and efflorescence phenomena on the wall paintings of Kastoria, a rural, non-metropolitan Byzantine town. A large number of representative samples were collected from the murals of three churches, dated to post-Byzantine era (14th-17th c. AD). The identified pigments for the red colour were hematite (Fe 2O 3), cinnabar (HgS) and minium (Pb 3O 4), while brown and yellow colours were attributed to mixtures of ochres (Fe-oxides and hydroxides) and lime. The utilization of admixtures of iron, lead and mercury compounds was also attested in order to render specific tones on the painted surfaces. Black and dark blue hues were prepared using black carbon and Mn in some cases. Grey colours were assigned to a mixture of black carbon and lime. Green colour is rather attributed to admixtures of Fe-rich minerals and lime and not to the commonly used green earths. Baryte (BaSO 4) was also evidenced as a filler or extender. Phosphorous was detected and connected to proteinaceous material and Mo and Sb were traced which are probably affiliated to Fe-oxides. Regarding efflorescing salts, the determined compounds are: calcite, dolomite, gypsum, halite, nitratine, natron and mirabilite, all of which are related to temperature and humidity changes and moisture fluctuations inside the wall paintings.

  2. Micro-Raman spectroscopy and X-ray fluorescence spectrometry on the characterization of the Persian pigments used in the pre-seventeenth century wall paintings of Masjid-i Jāme of Abarqū, central Iran.

    PubMed

    Holakooei, Parviz; Karimy, Amir-Hossein

    2015-01-05

    The pigments used in the wall paintings of the Masjid-i Jāme of Abarqū, central Iran, as less-known pigments used in the history of Persian painting, were investigated with micro-Raman spectroscopy, micro X-ray fluorescence (micro-XRF), scanning electron microscopy (SEM), and polarised light microscopy (PLM). The results showed that the green, red, and blue pigments were atacamite, red lead, and smalt mixed with natural ultramarine blue respectively applied on a white substrate composed of white huntite. Moreover, the blue smalt was identified to be used on the white huntite and under the paint layer in order to delineate the design of the wall paintings and to act as a rough sketch for the subsequent use of the other pigments. Glushinskite, as a less-reported mineral in historical wall paintings, was identified by micro-Raman spectroscopy and hypothesised to be associated with the degradation of the white huntite binder. Furthermore, micro-Raman spectroscopy studies surprisingly revealed the mineral woodhouseite sparely mixed with the green pigment. This paper strongly suggests micro-Raman spectroscopy for identifying archaeological pigments and for diagnosing their deterioration products. Conducting scientific methods of analysis, the pigments identified in this study are reported for the first time to be used in Persian wall paintings.

  3. Micro-Raman spectroscopy and X-ray fluorescence spectrometry on the characterization of the Persian pigments used in the pre-seventeenth century wall paintings of Masjid-i Jāme of Abarqū, central Iran

    NASA Astrophysics Data System (ADS)

    Holakooei, Parviz; Karimy, Amir-Hossein

    2015-01-01

    The pigments used in the wall paintings of the Masjid-i Jāme of Abarqū, central Iran, as less-known pigments used in the history of Persian painting, were investigated with micro-Raman spectroscopy, micro X-ray fluorescence (micro-XRF), scanning electron microscopy (SEM), and polarised light microscopy (PLM). The results showed that the green, red, and blue pigments were atacamite, red lead, and smalt mixed with natural ultramarine blue respectively applied on a white substrate composed of white huntite. Moreover, the blue smalt was identified to be used on the white huntite and under the paint layer in order to delineate the design of the wall paintings and to act as a rough sketch for the subsequent use of the other pigments. Glushinskite, as a less-reported mineral in historical wall paintings, was identified by micro-Raman spectroscopy and hypothesised to be associated with the degradation of the white huntite binder. Furthermore, micro-Raman spectroscopy studies surprisingly revealed the mineral woodhouseite sparely mixed with the green pigment. This paper strongly suggests micro-Raman spectroscopy for identifying archaeological pigments and for diagnosing their deterioration products. Conducting scientific methods of analysis, the pigments identified in this study are reported for the first time to be used in Persian wall paintings.

  4. The community distribution of bacteria and fungi on ancient wall paintings of the Mogao Grottoes

    PubMed Central

    Ma, Yantian; Zhang, He; Du, Ye; Tian, Tian; Xiang, Ting; Liu, Xiande; Wu, Fasi; An, Lizhe; Wang, Wanfu; Gu, Ji-Dong; Feng, Huyuan

    2015-01-01

    In this study, we compared the microbial communities colonising ancient cave wall paintings of the Mogao Grottoes exhibiting signs of biodeterioration. Ten samples were collected from five different caves built during different time periods and analysed using culture-independent and culture-dependent methods. The clone library results revealed high microbial diversity, including the bacterial groups Firmicutes, Proteobacteria, Actinobacteria, Acidobacteria, Cyanobacteria, Bacteroidetes, Gemmatimonadetes, Planctomycetes, and Chloroflexi and the fungal groups Euascomycetes, Dothideomycetes, Eurotiomycetes, Sordariomycetes, Saccharomycetes, Plectomycetes, Pezizomycetes, Zygomycota, and Basidiomycota. The bacterial community structures differed among the samples, with no consistent temporal or spatial trends. However, the fungal community diversity index correlated with the building time of the caves independent of environmental factors (e.g., temperature or relative humidity). The enrichment cultures revealed that many culturable strains were highly resistant to various stresses and thus may be responsible for the damage to cave paintings in the Mogao Grottoes. PMID:25583346

  5. D Survey of Pre-Hispanic Wall Painting with High Resolution Photogrammetry

    NASA Astrophysics Data System (ADS)

    Lucet, G.

    2013-07-01

    The survey and representation of pre-hispanic wall painting use to be done with traditional photography, we describe the difficulties and limitations found in this approach and we show another solution to improve the quality of this documentation. It relies on the use of photogrammetry and MicMac program. The calculated orthophotos have an accurate geometry, they are high resolution and the three-dimensional models present a high level of detail. We obtain a complete representation which satisfy the requirements of art historians and conservators to study the meanings of the paintings and their conservation state. Furthermore, as this improvement is achieved by following a particular strategy for the photo sessions and the mathematical processing on the images, it doesn't need the acquisition of additional equipment. We explain how we applied the method in the registration of a structure covered with pictorial representations that was discovered in the archaeological site of Las Higueras, México.

  6. The community distribution of bacteria and fungi on ancient wall paintings of the Mogao Grottoes

    NASA Astrophysics Data System (ADS)

    Ma, Yantian; Zhang, He; Du, Ye; Tian, Tian; Xiang, Ting; Liu, Xiande; Wu, Fasi; An, Lizhe; Wang, Wanfu; Gu, Ji-Dong; Feng, Huyuan

    2015-01-01

    In this study, we compared the microbial communities colonising ancient cave wall paintings of the Mogao Grottoes exhibiting signs of biodeterioration. Ten samples were collected from five different caves built during different time periods and analysed using culture-independent and culture-dependent methods. The clone library results revealed high microbial diversity, including the bacterial groups Firmicutes, Proteobacteria, Actinobacteria, Acidobacteria, Cyanobacteria, Bacteroidetes, Gemmatimonadetes, Planctomycetes, and Chloroflexi and the fungal groups Euascomycetes, Dothideomycetes, Eurotiomycetes, Sordariomycetes, Saccharomycetes, Plectomycetes, Pezizomycetes, Zygomycota, and Basidiomycota. The bacterial community structures differed among the samples, with no consistent temporal or spatial trends. However, the fungal community diversity index correlated with the building time of the caves independent of environmental factors (e.g., temperature or relative humidity). The enrichment cultures revealed that many culturable strains were highly resistant to various stresses and thus may be responsible for the damage to cave paintings in the Mogao Grottoes.

  7. The community distribution of bacteria and fungi on ancient wall paintings of the Mogao Grottoes.

    PubMed

    Ma, Yantian; Zhang, He; Du, Ye; Tian, Tian; Xiang, Ting; Liu, Xiande; Wu, Fasi; An, Lizhe; Wang, Wanfu; Gu, Ji-Dong; Feng, Huyuan

    2015-01-13

    In this study, we compared the microbial communities colonising ancient cave wall paintings of the Mogao Grottoes exhibiting signs of biodeterioration. Ten samples were collected from five different caves built during different time periods and analysed using culture-independent and culture-dependent methods. The clone library results revealed high microbial diversity, including the bacterial groups Firmicutes, Proteobacteria, Actinobacteria, Acidobacteria, Cyanobacteria, Bacteroidetes, Gemmatimonadetes, Planctomycetes, and Chloroflexi and the fungal groups Euascomycetes, Dothideomycetes, Eurotiomycetes, Sordariomycetes, Saccharomycetes, Plectomycetes, Pezizomycetes, Zygomycota, and Basidiomycota. The bacterial community structures differed among the samples, with no consistent temporal or spatial trends. However, the fungal community diversity index correlated with the building time of the caves independent of environmental factors (e.g., temperature or relative humidity). The enrichment cultures revealed that many culturable strains were highly resistant to various stresses and thus may be responsible for the damage to cave paintings in the Mogao Grottoes.

  8. Radiation induced degradation of polychlorinated biphenyls (PCBs) pollutants in paint scrapings.

    PubMed

    Singh, R K; Khandal, R K; Singh, Gurdeep

    2009-01-01

    Polychlorinated biphenyls (PCBs) are synthetic organic chemicals which have been commercially used worldwide in many specialty applications. In paints, PCBs were used because of their unique properties such as thermal stability, flame-resistance and low volatility. However, due to their adverse effects on human health and environment, the use of PCBs has now been banned. PCBs are today considered widespread pollutants in the global system . PCBs sources still exist in various products and in waste streams such as oil, paints, rubbers etc. Various remedial technologies have been developed in the world to detoxify PCBs. In the present study, radiolysis has been investigated as a safe means to reduce or destroy PCBs. Under this study, detoxification of PCBs in paint scrapings by gamma radiation using Cobalt 60 source has been investigated. The experimental results demonstrate that the gamma radiations can be an alternative environment- friendly technology for destroying PCBs. Gamma radiations also have the potential of being a preferred tool in comparison to the most widely used incineration method for destroying PCBs. The method used was found highly effective and destruction efficiency was as high as 91%. The degradation efficiency of PCBs was dependent on absorbed radiation dose, the type of PCBs and also on the source of paint scrapings.

  9. Stratigraphic investigation of wall painting fragments from Roman villas of the Sabina area

    NASA Astrophysics Data System (ADS)

    Paladini, Alessandra; Toschi, Francesco; Colosi, Francesca; Rubino, Gianluca; Santoro, Paola

    2015-01-01

    A number of plaster fragments of Roman wall paintings have been investigated through micro-Raman and laser-induced breakdown spectroscopy in order to characterize the different layers of paint. The samples come from two Roman villas in the Sabina area, a countryside close to Rome. The two sets of painted plasters present different palette of colors, pictorial technique and texture as the villas are dated one in the first century A.D. and the other in the second. Both micro-Raman and LIBS spectroscopies have supplied compositional information by consuming a microscopic amount of sample material and not requiring sophisticated and expansive preparation of the plaster. Depth profile analysis has also been performed by monitoring the intensities ratio of specific emission lines related to some characteristic elements. The spectroscopic results have been integrated with microscopic and profilometric investigation of the samples, allowing to analyze the depth and morphology of the craters produced by the penetration of the laser pulses into the samples.

  10. Solvent Extraction of Chemical Attribution Signature Compounds from Painted Wall Board: Final Report

    SciTech Connect

    Wahl, Jon H.; Colburn, Heather A.

    2009-10-29

    This report summarizes work that developed a robust solvent extraction procedure for recovery of chemical attribution signature (CAS) compound dimethyl methyl phosphonate (DMMP) (as well as diethyl methyl phosphonate (DEMP), diethyl methyl phosphonothioate (DEMPT), and diisopropyl methyl phosphonate (DIMP)) from painted wall board (PWB), which was selected previously as the exposed media by the chemical attribution scientific working group (CASWG). An accelerated solvent extraction approach was examined to determine the most effective method of extraction from PWB. Three different solvent systems were examined, which varied in solvent strength and polarity (i.e., 1:1 dichloromethane : acetone,100% methanol, and 1% isopropanol in pentane) with a 1:1 methylene chloride : acetone mixture having the most robust and consistent extraction for four original target organophosphorus compounds. The optimum extraction solvent was determined based on the extraction efficiency of the target analytes from spiked painted wallboard as determined by gas chromatography x gas chromatography mass spectrometry (GCxGC-MS) analysis of the extract. An average extraction efficiency of approximately 60% was obtained for these four compounds. The extraction approach was further demonstrated by extracting and detecting the chemical impurities present in neat DMMP that was vapor-deposited onto painted wallboard tickets.

  11. Photochemical degradation study of polyvinyl acetate paints used in artworks by Py-GC/MS.

    PubMed

    Wei, Shuya; Pintus, Valentina; Schreiner, Manfred

    2012-09-01

    Photochemical degradation of commercial polyvinyl acetate (PVAc) homopolymer and PVAc paints mixed with burnt umber, cobalt blue, cadmium red dark, nickel azo yellow and titanium white commonly used for artworks were studied by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR). Py-GC/MS with single-shot technique was used for the characterization of the thermal degradation of PVAc at different temperatures, while the double-shot technique of Py-GC/MS was used to reveal the differences in the specimens before and after UV ageing, including the changes of detectable amounts of deacetylation product - acetic acid and plasticizers such as diethyl phthalate (DEP). Furthermore, the relative concentration of the pyrolysis products of the paint samples could be measured and compared in the second step of the double-shot Py-GC/MS, which are highly dependent on the presence of pigments and the ageing status of PVAc paints.

  12. Photochemical degradation study of polyvinyl acetate paints used in artworks by Py–GC/MS

    PubMed Central

    Wei, Shuya; Pintus, Valentina; Schreiner, Manfred

    2012-01-01

    Photochemical degradation of commercial polyvinyl acetate (PVAc) homopolymer and PVAc paints mixed with burnt umber, cobalt blue, cadmium red dark, nickel azo yellow and titanium white commonly used for artworks were studied by pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) and Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR). Py–GC/MS with single-shot technique was used for the characterization of the thermal degradation of PVAc at different temperatures, while the double-shot technique of Py–GC/MS was used to reveal the differences in the specimens before and after UV ageing, including the changes of detectable amounts of deacetylation product – acetic acid and plasticizers such as diethyl phthalate (DEP). Furthermore, the relative concentration of the pyrolysis products of the paint samples could be measured and compared in the second step of the double-shot Py–GC/MS, which are highly dependent on the presence of pigments and the ageing status of PVAc paints. PMID:23024446

  13. Multi-analytical study of techniques and palettes of wall paintings of the monastery of Žiča, Serbia

    NASA Astrophysics Data System (ADS)

    Holclajtner-Antunović, Ivanka; Stojanović-Marić, Milica; Bajuk-Bogdanović, Danica; Žikić, Radiša; Uskoković-Marković, Snežana

    2016-03-01

    The present multi-analytical study concentrates on establishing the painting techniques and the identity of the wall painting materials used by the artists from the 13th and 14th centuries to decorate the Žiča monastery, Serbia. For this purpose, we demonstrate that micro-Raman spectroscopy is an efficient, non-destructive method with high spatial resolution which gives molecular and crystal structural information of a wide variety of both inorganic and organic materials. It is shown that elementary composition revealed through scanning electron microscopy with energy dispersive X-ray spectroscopy and energy dispersive X-ray fluorescence spectroscopy is necessary in some cases to confirm the identity of pigments and binders identified by micro-Raman spectroscopy. It was found that a fresco technique, in combination with mainly natural earth pigments such as red ochre, yellow ochre and green earth, was used. Expensive natural pigment lapis lazuli was exclusively used for obtaining blue colour while pure vermilion was used by the artists from the first period of decorations at the beginning of the 13th century. A mixture of pigments was used for attaining different colour shades. For the gilding of saint's haloes, thin golden foil was deposited over the tin sheet. In order to get a desirable optical and aesthetical impression, the metallic leaves were deposited over the yellow ochre preparatory layer. Deposits of gypsum on wall paintings as well as traces of weddellite are degradation products formed as a result of exposing wall paintings to environmental conditions.

  14. Multi-analytical study of techniques and palettes of wall paintings of the monastery of Žiča, Serbia.

    PubMed

    Holclajtner-Antunović, Ivanka; Stojanović-Marić, Milica; Bajuk-Bogdanović, Danica; Žikić, Radiša; Uskoković-Marković, Snežana

    2016-03-05

    The present multi-analytical study concentrates on establishing the painting techniques and the identity of the wall painting materials used by the artists from the 13th and 14th centuries to decorate the Žiča monastery, Serbia. For this purpose, we demonstrate that micro-Raman spectroscopy is an efficient, non-destructive method with high spatial resolution which gives molecular and crystal structural information of a wide variety of both inorganic and organic materials. It is shown that elementary composition revealed through scanning electron microscopy with energy dispersive X-ray spectroscopy and energy dispersive X-ray fluorescence spectroscopy is necessary in some cases to confirm the identity of pigments and binders identified by micro-Raman spectroscopy. It was found that a fresco technique, in combination with mainly natural earth pigments such as red ochre, yellow ochre and green earth, was used. Expensive natural pigment lapis lazuli was exclusively used for obtaining blue colour while pure vermilion was used by the artists from the first period of decorations at the beginning of the 13th century. A mixture of pigments was used for attaining different colour shades. For the gilding of saint's haloes, thin golden foil was deposited over the tin sheet. In order to get a desirable optical and aesthetical impression, the metallic leaves were deposited over the yellow ochre preparatory layer. Deposits of gypsum on wall paintings as well as traces of weddellite are degradation products formed as a result of exposing wall paintings to environmental conditions.

  15. In Situ Identification of Pigment Composition and Particle Size on Wall Paintings Using Visible Spectroscopy as a Noninvasive Measurement Method.

    PubMed

    Li, Junfeng; Wan, Xiaoxia; Bu, Yajing; Li, Chan; Liang, Jinxing; Liu, Qiang

    2016-11-01

    Noninvasive examination methods of chemical composition and particle size are presented here based on visible spectroscopy to achieve the identification and recording of mineral pigments used on ancient wall paintings. The normalized spectral curve, slope and curvature extracted from visible spectral reflectance are combined with adjustable weighting coefficients to construct the identification feature space, and Euclid distances between spectral reflectance from wall paintings and a reference database are calculated in the feature space as the discriminant criterion to identify the chemical composition of mineral pigments. A parametric relationship between the integral quantity of spectral reflectance and logarithm of mean particle size is established using a quadratic polynomial to accomplish the noninvasive prediction of mineral pigment particle size used on ancient wall paintings. The feasibility of the proposed methods is validated by the in situ nondestructive identification of the wall paintings in the Mogao Grottoes at Dunhuang. Chinese painting styles and historical evolution are then analyzed according to the identification results of 16 different grottoes constructed from the Sixteen Kingdoms to the Yuan Dynasty. © The Author(s) 2016.

  16. Enhanced delineation of degradation in aortic walls through OCT

    NASA Astrophysics Data System (ADS)

    Real, Eusebio; Val-Bernal, José Fernando; Revuelta, José M.; Pontón, Alejandro; Calvo Díez, Marta; Mayorga, Marta; López-Higuera, José M.; Conde, Olga M.

    2015-03-01

    Degradation of the wall of human ascending thoracic aorta has been assessed through Optical Coherence Tomography (OCT). OCT images of the media layer of the aortic wall exhibit micro-structure degradation in case of diseased aortas from aneurysmal vessels or in aortas prone to aortic dissections. The degeneration in vessel walls appears as low-reflectivity areas due to the invasive appearance of acidic polysaccharides and mucopolysaccharides within a typical ordered microstructure of parallel lamellae of smooth muscle cells, elastin and collagen fibers. An OCT indicator of wall degradation can be generated upon the spatial quantification of the extension of degraded areas in a similar way as conventional histopathology. This proposed OCT marker offers a real-time clinical insight of the vessel status to help cardiovascular surgeons in vessel repair interventions. However, the delineation of degraded areas on the B-scan image from OCT is sometimes difficult due to presence of speckle noise, variable SNR conditions on the measurement process, etc. Degraded areas could be outlined by basic thresholding techniques taking advantage of disorders evidences in B-scan images, but this delineation is not always optimum and requires complex additional processing stages. This work proposes an optimized delineation of degraded spots in vessel walls, robust to noisy environments, based on the analysis of the second order variation of image intensity of backreflection to determine the type of local structure. Results improve the delineation of wall anomalies providing a deeper physiological perception of the vessel wall conditions. Achievements could be also transferred to other clinical scenarios: carotid arteries, aorto-iliac or ilio-femoral sections, intracranial, etc.

  17. Methods for degrading or converting plant cell wall polysaccharides

    DOEpatents

    Berka, Randy; Cherry, Joel

    2008-08-19

    The present invention relates to methods for converting plant cell wall polysaccharides into one or more products, comprising: treating the plant cell wall polysaccharides with an effective amount of a spent whole fermentation broth of a recombinant microorganism, wherein the recombinant microorganism expresses one or more heterologous genes encoding enzymes which degrade or convert the plant cell wall polysaccharides into the one or more products. The present invention also relates to methods for producing an organic substance, comprising: (a) saccharifying plant cell wall polysaccharides with an effective amount of a spent whole fermentation broth of a recombinant microorganism, wherein the recombinant microorganism expresses one or more heterologous genes encoding enzymes which degrade or convert the plant cell wall polysaccharides into saccharified material; (b) fermenting the saccharified material of step (a) with one or more fermenting microoganisms; and (c) recovering the organic substance from the fermentation.

  18. Raman spectroscopic study of a post-medieval wall painting in need of conservation.

    PubMed

    Edwards, Howell G M; Farwell, Dennis W; Brooke, Christopher J

    2005-09-01

    Raman spectroscopic studies of four specimens from an important angel wall painting in need of conservation work in a medieval church have provided some information about the pigments and pigment compositions which will influence possible future preservation and restoration strategies. Excitation of the Raman spectra at 1,064 nm in macroscopic mode and at 785 nm in microscopic mode revealed that the white pigment on the angel's wings was a mixture of barytes with calcite and lead white in minor composition. Although the specimens provided were not directly associated with coloured regions of the painting, yellow and blue microcrystals were found and they were identified as chrome yellow and lazurite, respectively. Red and brown particles were identified as cinnabar/vermilion and haematite. Several green particles were also found but could not be identified. The green and blue crystals could be related to neighbouring coloured regions of the artwork and the yellow colour could be identified as a background to the angel figure. Particles of carbon were found to be dispersed throughout the specimens and can be ascribed to soot from candles, heating stoves or oil lamps providing lighting in the church. No evidence for biological deterioration was found from the spectra. The unusual pigment palette is strongly suggestive of a later date of painting than was originally believed but there is a possibility that an earlier rendition exists underneath. Following a review of the spectroscopic data, a more extensive sampling protocol is recommended, from which some stratigraphic evidence could identify the underlying plaster and possible artwork.

  19. Degradation study of XVIII century graffiti on the walls of Chiaramonte Palace (Palermo, Italy)

    NASA Astrophysics Data System (ADS)

    Alberghina, M. F.; Barraco, R.; Brai, M.; Casaletto, M. P.; Ingo, G. M.; Marrale, M.; Policarpo, D.; Schillaci, T.; Tranchina, L.

    2010-09-01

    A systematic investigation of the original materials and the degradation phenomena induced by soluble salts on the wall matrix and on the graffiti of the Inquisition jails of Chiaramonte Palace in Palermo (Italy) was carried out. Built in the XIV century, Chiaramonte Palace was used as Inquisition court during the XV-XVI centuries. The ancient graffiti, recently discovered, represent a unique historical witness of the prisoners that lived during that terrible period. In order to study the nature, the amount and the distribution of the salts in the masonry, stone materials sampled at different depth from the wall matrix and saline efflorescences were analysed. Different physical techniques were used, such as X-ray Photoelectron Spectroscopy, X-ray Fluorescence, Laser Induced Breakdown Spectroscopy, X-ray Diffraction and Ionic Chromatography. Results of the chemical and physical characterisation showed that the main cause of the degradation of graffiti and wall paintings was the presence of soluble salts, such as nitrates, chlorides and sulphates. Traces of oxalates, coming from a previous conservation treatment, were also found. The results obtained by the stratigraphical characterisation of soluble salts in the wall matrix can be used to recommend a procedure based on air humidification at high relative humidity values in order to avoid salt crystallisation and to prevent the crumbling process of the graffiti.

  20. A multi-analytical approach for the characterization of wall painting materials on contemporary buildings

    NASA Astrophysics Data System (ADS)

    Magrini, Donata; Bracci, Susanna; Cantisani, Emma; Conti, Claudia; Rava, Antonio; Sansonetti, Antonio; Shank, Will; Colombini, MariaPerla

    2017-02-01

    Samples from Keith Haring's wall painting of the Necker Children Hospital in Paris were studied by a multi-analytical protocol. X-ray fluorescence (XRF), powder X-ray diffraction (XRDP), Electron microscope (SEM-EDS), Infrared and Raman spectroscopy (μ-FT-IR and μ-Raman) measurements were performed in order to characterize the materials and to identify the art technique used to produce this contemporary work. Materials from the mural suffered from severe detachments of materials and several fragments were found on the ground beneath. Some of these fragments, which were representative of the whole palette and stratigraphic sequence, were collected and studied. The fragments were sufficiently large to enable non-invasive measurements to be performed in order to characterize the materials. A comparison of the data of the techniques applied revealed that Haring's palette was composed of organic pigments such as Naphtol red, phthalocyanine blue and green and Hansa yellow, in accordance with those used previously by the artist in other painted murals.

  1. Cinnabar alteration in archaeological wall paintings: an experimental and theoretical approach

    NASA Astrophysics Data System (ADS)

    Neiman, Madeleine Kegelman; Balonis, Magdalena; Kakoulli, Ioanna

    2015-11-01

    The red mineral pigment known as cinnabar (HgS) was commonly employed in Roman fresco wall paintings. Fresco artists of the period favored this pigment for its striking red color. However, upon excavation and exposure to air and light, cinnabar-pigmented surfaces recovered from archaeological contexts often proved to be unstable. Mural paintings colored with cinnabar that have been exposed in the open air frequently demonstrate a disfiguring, irreversible darkening of the surface. Traditionally, scholars have attributed this alteration to a light-induced phase change from red α-cinnabar to black β-cinnabar (meta-cinnabar). While this transformation has not been totally excluded, the prevailing view among conservation scientists is that chlorine plays a key role in the darkening process through the formation of light-sensitive mercury chloride compounds, or as a catalyst in the photochemical redox of Hg(II)S into Hg(0) and S(0). Using laboratory-based experiments and thermodynamic modeling, this paper attempts to further clarify the mechanism(s) and kinetics of cinnabar alteration in fresco applications, especially the role of light, humidity, and chlorine ions. Additionally, it explores possible pathways and preventive as well as remedial conservation treatments during or immediately following excavation, to inhibit or retard darkening of cinnabar-pigmented fresco surfaces.

  2. A multi-analytical approach for the characterization of wall painting materials on contemporary buildings.

    PubMed

    Magrini, Donata; Bracci, Susanna; Cantisani, Emma; Conti, Claudia; Rava, Antonio; Sansonetti, Antonio; Shank, Will; Colombini, MariaPerla

    2017-02-15

    Samples from Keith Haring's wall painting of the Necker Children Hospital in Paris were studied by a multi-analytical protocol. X-ray fluorescence (XRF), powder X-ray diffraction (XRDP), Electron microscope (SEM-EDS), Infrared and Raman spectroscopy (μ-FT-IR and μ-Raman) measurements were performed in order to characterize the materials and to identify the art technique used to produce this contemporary work. Materials from the mural suffered from severe detachments of materials and several fragments were found on the ground beneath. Some of these fragments, which were representative of the whole palette and stratigraphic sequence, were collected and studied. The fragments were sufficiently large to enable non-invasive measurements to be performed in order to characterize the materials. A comparison of the data of the techniques applied revealed that Haring's palette was composed of organic pigments such as Naphtol red, phthalocyanine blue and green and Hansa yellow, in accordance with those used previously by the artist in other painted murals.

  3. Cosmic billiards with painted walls in non-maximal supergravities: A worked out example

    NASA Astrophysics Data System (ADS)

    Fré, Pietro; Gargiulo, Floriana; Rulik, Ksenya

    2006-03-01

    The derivation of smooth cosmic billiard solutions by means of the compensator method, introduced by us sometimes ago, is extended to the case of supergravity with non-maximal supersymmetry. Here a new key feature is provided by the non-maximal split nature of the scalar coset manifold. To deal with this, one has to consider the theory of Tits-Satake projections leading to maximal split projected algebras, where the compensator method can be successfully applied and interesting solutions that display several smooth bounces can be derived. The generic bouncing feature of all exact solutions can thus be checked. From the analysis of the Tits-Satake projection emerges a regular scheme applicable to all non-maximal supergravity models and in particular a challenging so far unobserved structure, that of the paint group G. This latter, which is preserved through dimensional reduction, provides a powerful tool to codify solutions of the exact supergravity theories in terms of solutions of their Tits-Satake projected partners, which are much simpler and manageable. It appears that the dynamical walls on which the cosmic ball bounces come actually in painted copies rotated into each other by the paint group. So the effective cosmic dynamics is that dictated by the maximal split Tits-Satake manifold plus paint. In the present paper we work out in all minor details the example provided by N=6, D=4 supergravity, whose scalar manifold is the special Kählerian SO(12)/SU(6)×U(1) c-mapping in D=3 to the quaternionic E/SO(12)×SO(3). This choice was not random. It is the next one after maximal supergravity and at the same time can be reinterpreted in the context of N=2 supergravity. We plan indeed, in a future publication, to apply the results we obtained here, to the discussion of the Tits-Satake projection within the context of generic special Kähler manifolds. We also comment on the merging of the Tits-Satake projection with the affine Kač-Moody extension originating in

  4. Plant protein inhibitors of cell wall degrading enzymes.

    PubMed

    Juge, Nathalie

    2006-07-01

    Plant cell walls, which consist mainly of polysaccharides (i.e. cellulose, hemicelluloses and pectins), play an important role in defending plants against pathogens. Most phytopathogenic microorganisms secrete an array of cell wall degrading enzymes (CWDEs) capable of depolymerizing the polysaccharides in the plant host wall. In response, plants have evolved a diverse battery of defence responses including protein inhibitors of these enzymes. These include inhibitors of pectin degrading enzymes such as polygalacturonases, pectinmethyl esterases and pectin lyases, and hemicellulose degrading enzymes such as endoxylanases and xyloglucan endoglucanases. The discovery of these plant inhibitors and the recent resolution of their three-dimensional structures, free or in complex with their target enzymes, provide new lines of evidence regarding their function and evolution in plant-pathogen interactions.

  5. Hyperspectral remote sensing techniques applied to the noninvasive investigation of mural paintings: a feasibility study carried out on a wall painting by Beato Angelico in Florence

    NASA Astrophysics Data System (ADS)

    Cucci, Costanza; Picollo, Marcello; Chiarantini, Leandro; Sereni, Barbara

    2015-06-01

    Nowadays hyperspectral imaging is a well-established methodology for the non-invasive diagnostics of polychrome surfaces, and is increasingly utilized in museums and conservation laboratories for documentation purposes and in support of restoration procedures. However, so far the applications of hyperspectral imaging have been mainly limited to easel paintings or paper-based artifacts. Indeed, specifically designed hyperspectral imagers, are usually used for applications in museum context. These devices work at short-distances from the targets and cover limited size surfaces. Instead, almost still unexplored remain the applications of hyperspectral imaging to the investigations of frescoes and large size mural paintings. For this type of artworks a remote sensing approach, based on sensors capable of acquiring hyperspectral data from distances of the order of tens of meters, is needed. This paper illustrates an application of hyperspectral remote sensing to an important wall-painting by Beato Angelico, located in the San Marco Museum in Florence. Measurements were carried out using a re-adapted version of the Galileo Avionica Multisensor Hyperspectral System (SIM-GA), an avionic hyperspectral imager originally designed for applications from mobile platforms. This system operates in the 400-2500 nm range with over 700 channels, thus guaranteeing acquisition of high resolution hyperspectral data exploitable for materials identification and mapping. In the present application, the SIM-GA device was mounted on a static scanning platform for ground-based applications. The preliminary results obtained on the Angelico's wall-painting are discussed, with highlights on the main technical issues addressed to optimize the SIM-GA system for new applications on cultural assets.

  6. Effect of resin content and substrate on the emission of BTEX and carbonyls from low-VOC water-based wall paint.

    PubMed

    Zhao, Ping; Cheng, Yu-Hsiang; Lin, Chi-Chi; Cheng, Yu-Lin

    2016-02-01

    The primary aim of this work is to explore the effect of resin content and the effect of substrate on the emission of benzene, toluene, ethylbenzene, and xylene (BTEX) and carbonyls from low-VOC water-based wall paint. Four low-volatile organic compound (VOC) paints include paints A (20% acrylic), B (30% acrylic), C (20% polyvinyl acetate), and D (30% polyvinyl acetate) were painted on stainless steel specimen for the study of resin effect. Green calcium silicate, green cement, and stainless steel were painted with paints A and C for the study of substrate effect. Concentrations of the VOCs in the chamber decreased with the elapsed time. Both resin type and resin quantity in paint had effects on VOC emissions. Paints with acrylic resin emitted less BTEX and carbonyls than paints with polyvinyl acetate resin. However, the effects of resin quantity varied with VOCs. Porous substrates were observed to interact more strongly with paints than inert substrates. Both green calcium silicate and green cement substrates have strong power of adsorption of VOCs from wall paints, namely toluene, formaldehyde, acetaldehyde, 2-butanone, methacrolein, butyraldehyde, and benzaldehyde. Some compounds like toluene, formaldehyde, and butyaldehyde were desorbed very slowly from green calcium silicate and green cement substrates.

  7. Temperature-related degradation and colour changes of historic paintings containing vivianite

    NASA Astrophysics Data System (ADS)

    Čermáková, Zdeňka; Švarcová, Silvie; Hradilová, Janka; Bezdička, Petr; Lančok, Adriana; Vašutová, Vlasta; Blažek, Jan; Hradil, David

    2015-04-01

    Temperature-related degradation of pure synthetic as well as partly oxidised natural vivianite has been studied by high-temperature X-ray diffraction (HT-XRD) covering the whole extent of the temperature-related stability of its structure. While temperatures around 70 °C are already damaging to vivianite, exposition to 160 °C results in complete amorphisation of both the vivianite and its oxidation products. As indicated by Mössbauer spectroscopy, temperature-induced oxidation of vivianite starts at 90 °C. To study the occurring structural as well as accompanying colour changes in more detail, model vivianite paint layer samples with different historic binders were prepared and subjected to increased temperatures. Exposition to 80 °C caused pronounced colour changes of all the samples: ground natural blue vivianite became grey - a colour change which has been described in actual works of art. Regarding the binders, the oil seemed to facilitate the transfer of heat to vivianite's grains. To simulate conditions of conservation treatment under which the painting is exposed to increased temperatures, oil-on-canvas mock-ups with vivianite were prepared and relined in a traditional way using iron. The treatment affected preferentially larger grains of vivianite; the micro-samples documented their change to grey, and their Raman spectra showed the change from vivianite to metavivianite.

  8. Temperature-related degradation and colour changes of historic paintings containing vivianite.

    PubMed

    Čermáková, Zdeňka; Švarcová, Silvie; Hradilová, Janka; Bezdička, Petr; Lančok, Adriana; Vašutová, Vlasta; Blažek, Jan; Hradil, David

    2015-04-05

    Temperature-related degradation of pure synthetic as well as partly oxidised natural vivianite has been studied by high-temperature X-ray diffraction (HT-XRD) covering the whole extent of the temperature-related stability of its structure. While temperatures around 70°C are already damaging to vivianite, exposition to 160°C results in complete amorphisation of both the vivianite and its oxidation products. As indicated by Mössbauer spectroscopy, temperature-induced oxidation of vivianite starts at 90°C. To study the occurring structural as well as accompanying colour changes in more detail, model vivianite paint layer samples with different historic binders were prepared and subjected to increased temperatures. Exposition to 80°C caused pronounced colour changes of all the samples: ground natural blue vivianite became grey--a colour change which has been described in actual works of art. Regarding the binders, the oil seemed to facilitate the transfer of heat to vivianite's grains. To simulate conditions of conservation treatment under which the painting is exposed to increased temperatures, oil-on-canvas mock-ups with vivianite were prepared and relined in a traditional way using iron. The treatment affected preferentially larger grains of vivianite; the micro-samples documented their change to grey, and their Raman spectra showed the change from vivianite to metavivianite.

  9. Assessment of in-depth degradation of artificially aged triterpenoid paint varnishes using nonlinear microscopy techniques.

    PubMed

    Filippidis, George; Mari, Meropi; Kelegkouri, Lambrini; Philippidis, Aggelos; Selimis, Aleksandros; Melessanaki, Kristallia; Sygletou, Maria; Fotakis, Costas

    2015-04-01

    The present work investigates the applicability of nonlinear imaging microscopy for the precise assessment of degradation of the outer protective layers of painted artworks as a function of depth due to aging. Two fresh and artificially aged triterpenoid varnishes, dammar and mastic, were tested. Nonlinear imaging techniques have been employed as a new diagnostic tool for determination of the exact thickness of the affected region due to artificial aging of the natural varnishes. The measured thicknesses differ from the calculated mean penetration depths of the samples. These nondestructive, high resolution modalities are valuable analytical tools for aging studies and they have the potential to provide unique in-depth information. Single photon laser induced fluorescence measurements and Raman spectroscopy were used for the integrated investigation and analysis of aging effects in varnishes.

  10. Wall Painting Investigation by Means of Non-invasive Terahertz Time-Domain Imaging (THz-TDI): Inspection of Subsurface Structures Buried in Historical Plasters

    NASA Astrophysics Data System (ADS)

    Dandolo, Corinna Ludovica Koch; Jepsen, Peter Uhd

    2016-02-01

    Characterization of subsurface features of wall paintings is important in conservation and technical art history as well as in building archaeology and architecture fields. In this study, an area of the apsidal wall painting of Nebbelunde Church (Rødby, Denmark) has been investigated by means of terahertz time-domain imaging (THz-TDI). Subsurface structures have been detected at different depths inside the lime-based plaster of the wall painting until approximately 1 cm from the surface. The surface morphology of the buried structures has been 3D imaged in detail, providing a substantial contribution in their characterization.

  11. Investigation of the gilding technique in two post-Byzantine wall paintings using micro-analytical techniques

    NASA Astrophysics Data System (ADS)

    Katsibiri, Olga; Boon, Jaap J.

    2004-10-01

    The main churches of two important monasteries in Thessalia, Central Greece, are decorated with wall paintings that hail from the post-Byzantine period. The mural decoration of the main church of the St. Byssarionas Monastery at Doussiko has been attributed to the iconographer Tzortzis. The same painter is believed to have also operated in the main church of the Transfiguration Monastery at the monastic community of Meteora. The light microscopic (LM) examination of the cross-sections of samples taken from the gilded areas of the wall paintings, together with the direct temperature resolved mass spectrometric (DTMS) and scanning electron microscopy-energy dispersive X-ray spectroscopic (SEM-EDX) analysis, revealed a further resemblance of the materials and the methodology employed. The gold leaf was applied to the paintings by means of a mordant, which contains linseed oil mixed with a lead-containing dryer and an earth pigment or clay. The present study can constitute additional evidence to reinforce the idea that the two churches may have been painted by the same painter or workshop.

  12. Analysis of Roman age wall paintings found in Pordenone, Trieste and Montegrotto.

    PubMed

    Mazzocchin, G A; Agnoli, F; Salvadori, M

    2004-10-20

    The aim of the present work is the study of many fragments of wall painting from archaeological excavations in three different Roman age sites dating back to the I Century before Common Era: Pordenone (località Torre); Trieste (Crosada) and Padova (Montegrotto). The techniques used were optical microscopy, scanning electron microscopy (SEM), equipped with a EDS microanalysis detector, X-rays powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Fourier transform Raman spectroscopy (FT-Raman) and electron paramagnetic resonance (EPR) spectroscopy. The identified pigments were: cinnabar, hematite, celadonite, glauconite, cuprorivaite (Egyptian blue), yellow and red ochre, calcite, limonite, coal black. In general, the mortar preparation did not correspond to the complex procedure suggested by Vitruvius (De Architectura), but generally showed a porous layer, with crushed grains under the pigment layer. In some cases, two superimposed pigment layers were found: yellow superimposed on both red and pink, black on pink, green on black. The slight differences we found in the use of the pigments in the three studied sites might show that the same technology, culture and taste spread all over the Roman Empire in North Eastern Italy (X(a) Regio Venetia et Histria).

  13. Spectrofluorimetric study of the ageing of mixtions used in the gildings of mediaeval wall paintings.

    PubMed

    Mounier, Aurélie; Belin, Colette; Daniel, Floréal

    2011-06-01

    In the Middle Ages, we could find gildings on mural paintings. Gold, silver or tin leaves were applied according to distemper or mixtion technique. For the first one, a binder as glue is necessary, and for the second, a lipidic binder is used to stick the metallic leaf. Studies of gildings materials characterization show that the mixtion technique, with a mordant, is the most common. Linseed oil seems to be the binder used. It is always mixed with a siccative agent as lead. Because of bad conditions of conservation, the gildings do not resist anymore, only remain traces of metal or the adhesive under-layer. Thanks to the binder fluorescence, we can nowadays detect ancient gildings. The purpose of this paper is to study the degradation of the linseed oil, generally mixed with lead white to give a mordant for the metallic leaf, by spectrofluorimetry. To understand in situ fluorescence, gildings recreations, linseed oil and lead white are aged in hydro-thermal and ultraviolet (UV) light (313 nm) climatic rooms and under UV irradiation. Irradiation wavelengths are chosen according to the maximum of absorption of linseed oil and the bibliography (296, 313 and 366 nm = mercury bands). In comparison with results (in situ UV lamp, spectrofluorimetry), excitation wavelength chosen is 366 nm. Irradiations at 366 nm of linseed oil and linseed oil mixed with lead white show the most degrading effect in the fluorescence to the big wavelength. Lead white plays an important siccative role; it increases the intensity fluorescence and accelerates the drying of linseed oil. This study also allows to show that 366 nm wavelength is good for the in situ observation.

  14. Study of the effects of low-fluence laser irradiation on wall paintings: Test measurements on fresco model samples

    NASA Astrophysics Data System (ADS)

    Raimondi, Valentina; Cucci, Costanza; Cuzman, Oana; Fornacelli, Cristina; Galeotti, Monica; Gomoiu, Ioana; Lognoli, David; Mohanu, Dan; Palombi, Lorenzo; Picollo, Marcello; Tiano, Piero

    2013-11-01

    Laser-induced fluorescence is widely applied in several fields as a diagnostic tool to characterise organic and inorganic materials and could be also exploited for non-invasive remote investigation of wall paintings using the fluorescence lidar technique. The latter relies on the use of a low-fluence pulsed UV laser and a telescope to carry out remote spectroscopy on a given target. A first step to investigate the applicability of this technique is to assess the effects of low-fluence laser radiation on wall paintings. This paper presents a study devoted to investigate the effects of pulsed UV laser radiation on a set of fresco model samples prepared using different pigments. To irradiate the samples we used a tripled-frequency Q-switched Nd:YAG laser (emission wavelength: 355 nm; pulse width: 5 ns). We varied the laser fluence from 0.1 mJ/cm2 to 1 mJ/cm2 and the number of laser pulses from 1 to 500 shots. We characterised the investigated materials using several diagnostic and analytical techniques (colorimetry, optical microscopy, fibre optical reflectance spectroscopy and ATR-FT-IR microscopy) to compare the surface texture and their composition before and after laser irradiation. Results open good prospects for a non-invasive investigation of wall paintings using the fluorescence lidar technique.

  15. Polysaccharide-degrading Enzymes are Unable to Attack Plant Cell Walls without Prior Action by a "Wall-modifying Enzyme".

    PubMed

    Karr, A L; Albersheim, P

    1970-07-01

    A study of the degradation of plant cell walls by the mixture of enzymes present in Pectinol R-10 is described. A "wall-modifying enzyme" has been purified from this mixture by a combination of diethylaminoethyl cellulose, Bio Gel P-100, and carboxymethyl cellulose chromatography. Treatment of cell walls with the "wall-modifying enzyme" is shown to be a necessary prerequisite to wall degradation catalyzed by a mixture of polysaccharide-degrading enzymes prepared from Pectinol R-10 or by an alpha-galactosidase secreted by the pathogenic fungus Colletotrichum lindemuthianum. The action of the "wall-modifying enzyme" on cell walls is shown to result in both a release of water-soluble, 70% ethanol-insoluble polymers and an alteration of the residual cell wall. A purified preparation of the "wall-modifying enzyme" is unable to degrade a wide variety of polysaccharide, glycoside, and peptide substrates. However, the purified preparation of wall-modifying enzyme has a limited ability to degrade polygalacturonic acid. The fact that polygalacturonic acid inhibits the ability of the "wall-modifying enzyme" to affect cell walls suggests that the "wall-modifying enzyme" may be responsible for the limited polygalacturonic acid-degrading activity present in the purified preparation. The importance of a wall-modifying enzyme in developmental processes and in pathogenesis is discussed.

  16. Laser paint removal on the outside walls of the Church Abbey Saint Adoeno in Bisceglie (BAT), Italy: a case study

    NASA Astrophysics Data System (ADS)

    Daurelio, G.; Catalano, I. M.; Bassi, P.

    2010-09-01

    It is the oldest church in the city after the cathedral. It is among the purest examples of Romanesque. It was founded in 1074 and expenses for its construction helped the inhabitants of the agricultural hamlets of the Cirignano, Pacciano and Zappino. The church was dedicated to St. Adoeno Dado, bishop of Rouen, protector of Norman, because , according to tradition, the building also participated Norman soldiers. San Adoeno church has a façade at cusp with a truncated tympanum , crowned by an eagle. In the centre of the façade there is a rose ornament surrounded by four lions and a statue of St. Adoeno ( Figs. A to I ). On the outside walls of this Abbey many graffiti, produced by different coloured spray paints were found. After the usual photographical tests some Laser Paint Removal trials were executed to verify the damage threshold of the calcareous stony substrate as well as the possibility to ablate these paints by a Nd - YAG laser in Q-Switch mode. Even if all the classical four laser paint ablation techniques were employed some paints showed a great difficulty to be removed from the substrate. For these ones it was necessary to increase at maximum both the energy per pulse and the fluence value for obtaining some acceptable result but the substrate looked turned pale. It was decided to remove a small amount of these paints and subject to chemical analysis for determining whether they were acrylic based. At the same time it was investigated on the type of limestone substrate that appeared more porous and less hard on the surface than the common local limestone marble basin, that is, Trani or Bisceglie. So, on the light of these investigations, the possible solution for this hard laser ablation problem was carried out with an acceptable final result.

  17. Transcriptional regulation of plant cell wall degradation by filamentous fungi.

    PubMed

    Aro, Nina; Pakula, Tiina; Penttilä, Merja

    2005-09-01

    Plant cell wall consists mainly of the large biopolymers cellulose, hemicellulose, lignin and pectin. These biopolymers are degraded by many microorganisms, in particular filamentous fungi, with the aid of extracellular enzymes. Filamentous fungi have a key role in degradation of the most abundant biopolymers found in nature, cellulose and hemicelluloses, and therefore are essential for the maintenance of the global carbon cycle. The production of plant cell wall degrading enzymes, cellulases, hemicellulases, ligninases and pectinases, is regulated mainly at the transcriptional level in filamentous fungi. The genes are induced in the presence of the polymers or molecules derived from the polymers and repressed under growth conditions where the production of these enzymes is not necessary, such as on glucose. The expression of the genes encoding the enzymes is regulated by various environmental and cellular factors, some of which are common while others are more unique to either a certain fungus or a class of enzymes. This review summarises our current knowledge on the transcriptional regulation, focusing on the recently characterized transcription factors that regulate genes coding for enzymes involved in the breakdown of plant cell wall biopolymers.

  18. Determination of airborne isocyanates generated during the thermal degradation of car paint in body repair shops.

    PubMed

    Boutin, Michel; Dufresne, André; Ostiguy, Claude; Lesage, Jacques

    2006-06-01

    Polyurethanes are widely used in car paint formulations. During thermal degradation, such polymeric systems can generate powerful asthmatic sensitizing agents named isocyanates. In body repair shops, the thermal degradation of car paint can occur during abrasive processes that generate enough heat to involve release of isocyanates in air. An environmental monitoring study was performed in two body repair training schools and in a body repair shop to evaluate the workers' exposure to isocyanates during cutting, grinding and orbital sanding operations. For sampling, cassettes containing two 1-(2-methoxyphenyl)piperazine (MOPIP)-coated glass fiber filters (MFs) ( approximately 5 mg of MOPIP per filter) and bubblers containing 15 ml of MOPIP solution in toluene (1.0 mg ml(-1)) backed at the outlet with cassettes containing two MFs were used. Tandem mass spectrometry was used to analyze the MOPIP derivatives of isocyanic acid (HNCO), all the linear aliphatic isocyanates ranging from methyl isocyanate (Me-i) to hexyl isocyanate, all the alkenyl isocyanates ranging from propylene isocyanate to hexylene isocyanate, 1,6-hexamethylene diisocyanate (HDI), trans- and cis-isophorone diisocyanate (IPDI), 2,4- and 2,6-toluene diisocyanate (TDI), 2,4'-; 2,2'- and 4,4'-methylenediphenyl diisocyanate (MDI), phenyl isocyanate (Ph-i) and p-toluene isocyanate (p-Tol-i). The instrumental detection limits (LOD) were in the 0.13-0.75 microg of NCO per m(3) range for 15 l air samples converted into 3 ml liquid samples. The isocyanate concentrations detected in the workers' breathing zone were in the 1.07-9.80 microg of NCO per m(3) range for cutting, 0.63-3.62 microg of NCO per m(3) range for grinding and 0-1.29 microg of NCO per m(3) range for sanding. However, a rapid decrease of the isocyanate concentration was observed while moving away from the emission source. Among the isocyanates detected the most abundant were the monomers (MDI, HDI, TDI and IPDI) and Me-i.

  19. Extracellular entrapment and degradation of single-walled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Farrera, Consol; Bhattacharya, Kunal; Lazzaretto, Beatrice; Andón, Fernando T.; Hultenby, Kjell; Kotchey, Gregg P.; Star, Alexander; Fadeel, Bengt

    2014-05-01

    Neutrophils extrude neutrophil extracellular traps (NETs) consisting of a network of chromatin decorated with antimicrobial proteins to enable non-phagocytic killing of microorganisms. Here, utilizing a model of ex vivo activated human neutrophils, we present evidence of entrapment and degradation of carboxylated single-walled carbon nanotubes (SWCNTs) in NETs. The degradation of SWCNTs was catalyzed by myeloperoxidase (MPO) present in purified NETs and the reaction was facilitated by the addition of H2O2 and NaBr. These results show that SWCNTs can undergo acellular, MPO-mediated biodegradation and imply that the immune system may deploy similar strategies to rid the body of offending microorganisms and engineered nanomaterials.Neutrophils extrude neutrophil extracellular traps (NETs) consisting of a network of chromatin decorated with antimicrobial proteins to enable non-phagocytic killing of microorganisms. Here, utilizing a model of ex vivo activated human neutrophils, we present evidence of entrapment and degradation of carboxylated single-walled carbon nanotubes (SWCNTs) in NETs. The degradation of SWCNTs was catalyzed by myeloperoxidase (MPO) present in purified NETs and the reaction was facilitated by the addition of H2O2 and NaBr. These results show that SWCNTs can undergo acellular, MPO-mediated biodegradation and imply that the immune system may deploy similar strategies to rid the body of offending microorganisms and engineered nanomaterials. Electronic supplementary information (ESI) available: Suppl. Fig. 1 - length distribution of SWCNTs; suppl. Fig. 2 - characterization of pristine vs. oxidized SWCNTs; suppl. Fig. 3 - endotoxin evaluation; suppl. Fig. 4 - NET characterization; suppl. Fig. 5 - UV-Vis/NIR analysis of biodegradation of oxidized SWCNTs; suppl. Fig. 6 - cytotoxicity of partially degraded SWCNTs. See DOI: 10.1039/c3nr06047k

  20. Elemental and Molecular Segregation in Oil Paintings due to Lead Soap Degradation.

    PubMed

    Chen-Wiegart, Yu-Chen Karen; Catalano, Jaclyn; Williams, Garth J; Murphy, Anna; Yao, Yao; Zumbulyadis, Nicholas; Centeno, Silvia A; Dybowski, Cecil; Thieme, Juergen

    2017-09-14

    The formation of Pb, Zn, and Cu carboxylates (soaps) has caused visible deterioration in hundreds of oil paintings dating from the 15th century to the present. Through transport phenomena not yet understood, free fatty acids in the oil binding medium migrate through the paint and react with pigments containing heavy metals to form soaps. To investigate the complex correlation among the elemental segregation, types of chemical compounds formed, and possible mechanisms of the reactions, a paint sample cross-section from a 15th century oil painting was examined by synchrotron X-ray techniques. X-ray fluorescence (XRF) microscopy, quantified with elemental correlation density distribution, showed Pb and Sn segregation in the soap-affected areas. X-ray absorption near edge structure (XANES) around the Pb-L3 absorption edge showed that Pb pigments and Pb soaps can be distinguished while micro-XANES gave further information on the chemical heterogeneity in the paint film. The advantages and limitations of these synchrotron-based techniques are discussed and compared to those of methods routinely used to analyze paint samples. The results presented set the stage for improving the information extracted from samples removed from works of art and for correlating observations in model paint samples to those in the naturally aged samples, to shed light onto the mechanism of soap formation.

  1. Wall paintings facies and their possible genetic correlates in the ancient Pompeii: A bio-anthropologic message from the past?

    PubMed

    Ponti, Giovanni; Manfredini, Marco; Ruini, Cristel

    2016-09-10

    The figurative arts and precisely the ancient Pompeian wall paintings portraits can provide an additional source of information in supplementing bio-anthropological studies. There are several genetic diseases with a wide spectrum of congenital bone stigmata in association to distinctive facial features. Gorlin-Goltz syndrome, also named nevoid basal cell carcinoma syndrome, is an autosomal dominant syndrome characterized by unusual skeletal changes, such as macrocephaly, facial asymmetry, hypertelorism, frontal and parietal bossing caused by germline mutations of the gene PTCH1. The Gorlin syndrome, clinically defined in 1963, existed during Dynastic Egyptian times, as revealed by a spectrum of skeletal findings compatible with the syndrome in mummies dating back to three thousand years ago and, most likely, in the ancient population of Pompeii. In the present research, we discuss the potential relationship between Pompeian wall paintings portrait and the cranio-metric bone changes revealed among the Pompeian skull collections assuming that the ancient portraits can constitute an important tool that should be strictly integrated with osteologic and biomolecular data in order to argue a syndromic diagnosis in ancient population. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Radiation Induced Degradation of the White Thermal Control Paints Z-93 and Z-93P

    NASA Technical Reports Server (NTRS)

    Edwards, D. L.; Zwiener, J. M.; Wertz, G. E.; Vaughn, J. A.; Kamenetzky, R. R.; Finckenor, M. M.; Meshishnek, M. J.

    1996-01-01

    This paper details a comparison analysis of the zinc oxide pigmented white thermal control paints Z-93 and Z-93P. Both paints were simultaneously exposed to combined space environmental effects and analyzed using an in-vacuo reflectance technique. The dose applied to the paints was approximately equivalent to 5 years in a geosynchronous orbit. This comparison analysis showed that Z-93P is an acceptable substitute for Z-93. Irradiated samples of Z-93 and Z-93P were subjected to additional exposures of ultraviolet (UV) radiation and analyzed using the in-vacuo reflectance technique to investigate UV activated reflectance recovery. Both samples showed minimal UV activated reflectance recovery after an additional 190 equivalent sun hour (ESH) exposure. Reflectance response utilizing nitrogen as a repressurizing gas instead of air was also investigated. This investigation found the rates of reflectance recovery when repressurized with nitrogen are slower than when repressurized with air.

  3. Analytical imaging studies of the migration of degraded orpiment, realgar, and emerald green pigments in historic paintings and related conservation issues

    DOE PAGES

    Keune, Katrien; Mass, Jennifer; Mehta, Apurva; ...

    2016-04-21

    Yellow orpiment (As2S3) and red–orange realgar (As4S4) photo-degrade and the nineteenth-century pigment emerald green (Cu(C2H3O2)2·3Cu(AsO2)2) degrades into arsenic oxides. Because of their solubility in water, arsenic oxides readily migrate and are found throughout the multi-layered paint system. The widespread arsenic migration has consequences for conservation, and this paper provides better insight into the extent of the problem. Five paint samples containing orpiment, realgar or emerald green pigments deriving from paintings by De Heem (17th C), Van Gogh (19th C), Rousseau (19th C), an unknown 17th C northern European artist and an Austrian painted cupboard (19th C) were investigated using SEM/EDX,more » imaging ATR-FTIR and arsenic (As) K–edge μ-XANES to obtain the spatial distribution and chemical speciation of arsenic in the paint system. In all of the samples investigated arsenic had migrated throughout the multi-layered paint structure of the art object, from support to varnish. Furthermore, As5+-species were found throughout the entire paint sample. We hypothesize that arsenic trioxide is first formed, dissolves in water, further oxidizes to arsenic pentaoxide, and then reacts with lead, calcium and other ions and is deposited in the paint system as insoluble arsenates. Since the degradation of arsenic pigments such as orpiment, realgar and emerald green occurs through a highly mobile intermediate stage, it not only affects the regions rich in arsenic pigments, but also the entire object, including substrate and top varnish layers. Furthermore, because of this widespread potential for damage, preventing degradation of arsenic pigments should be prioritized and conservators should minimize exposure of objects containing arsenic pigments to strong light, large fluctuations in relative humidity and water-based cleaning agents.« less

  4. Portable Raman, DRIFTS, and XRF Analysis to Diagnose the Conservation State of Two Wall Painting Panels from Pompeii Deposited in the Naples National Archaeological Museum (Italy).

    PubMed

    Madariaga, Juan Manuel; Maguregui, Maite; Castro, Kepa; Knuutinen, Ulla; Martínez-Arkarazo, Irantzu

    2016-01-01

    This work presents a methodology that combines spectroscopic speciation, performed through portable Raman spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and energy dispersive X-ray fluorescence spectrometry (ED-XRF) working in situ, and thermodynamic speciation to diagnose the environmental impacts, induced by past and current events, on two wall painting panels (Nos. 9103 and 9255) extracted more than 150 years ago from the walls of a Pompeian house (Marcus Lucretius House, Regio IX, Insula 3, House 5/24) and deposited in the Naples National Archaeological Museum (MANN). The results show a severe chemical attack of the acid gases that can be explained only by the action of H2S during and just after the eruption of the Vesuvius volcano, that expelled a high concentration of sulfur gases. This fact can be considered as the most important process impacting the wall painting panels deposited in the museum, while the rain-wash processes and the colonization of microorganisms have not been observed in contrast to the impacts shown by the wall paintings left outside in the archaeological site of Pompeii. Moreover, the systematic presence of lead traces and strontium in both wall paintings suggests their presence as impurities of the calcite mortars (intonacco) or calcite binder of these particular fresco Pompeian murals. © The Author(s) 2015.

  5. Egyptian Tomb Painting.

    ERIC Educational Resources Information Center

    Schroeder, Liesa

    1999-01-01

    Provides an activity where sixth-grade students replicated the Egyptian art form of tomb painting. Explains that the students researched information about Egyptian culture and history in order to familiarize themselves with Egyptian wall-painting style. Discusses the process of creating tomb paintings in detail. (CMK)

  6. Recording Earthen Architecture at the Peruvian Andes: the Case of KUÑO Tambo CHURCH'S Historic Wall Paintings

    NASA Astrophysics Data System (ADS)

    Percy, K.; Hanley, C.; Santana Quintero, M.; Fai, S.; Ouimet, C.; Cancino, C.; Rainer, L.; Villacorta-Santamato, L.

    2013-07-01

    According to UNESCO "Earthen architecture is one of the most original and powerful expressions of our ability to create a built environment with readily available resources. It includes a great variety of structures, ranging from mosques, palaces and granaries, to historic city centres, cultural landscapes and archaeological sites" (WHEAP, 2007). This contribution looks at developing effective methods for recording earthen historic structures for their rehabilitation and preservation using the Kuño Tambo church in Peru, which is a Peruvian national historic site that requires serious rehabilitation work, as a case study. This project describes the compilation of an effective metric record of the "state-of-conservation" - "as found" of wall paintings in this important and remote building using a toolbox of different "off-the-shelf" heritage recording techniques. This approach was applied by Carleton Immersive Media Studio (CIMS), as part of the Earthen Architecture Initiative of the Getty Conservation Institute (GCI).

  7. 2D X-ray and FTIR micro-analysis of the degradation of cadmium yellow pigment in paintings of Henri Matisse

    NASA Astrophysics Data System (ADS)

    Pouyet, E.; Cotte, M.; Fayard, B.; Salomé, M.; Meirer, F.; Mehta, A.; Uffelman, E. S.; Hull, A.; Vanmeert, F.; Kieffer, J.; Burghammer, M.; Janssens, K.; Sette, F.; Mass, J.

    2015-11-01

    The chemical and physical alterations of cadmium yellow (CdS) paints in Henri Matisse's The Joy of Life (1905-1906, The Barnes Foundation) have been recognized since 2006, when a survey by portable X-ray fluorescence identified this pigment in all altered regions of the monumental painting. This alteration is visible as fading, discoloration, chalking, flaking, and spalling of several regions of light to medium yellow paint. Since that time, synchrotron radiation-based techniques including elemental and spectroscopic imaging, as well as X-ray scattering have been employed to locate and identify the alteration products observed in this and related works by Henri Matisse. This information is necessary to formulate one or multiple mechanisms for degradation of Matisse's paints from this period, and thus ensure proper environmental conditions for the storage and the display of his works. This paper focuses on 2D full-field X-ray Near Edge Structure imaging, 2D micro-X-ray Diffraction, X-ray Fluorescence, and Fourier Transform Infra-red imaging of the altered paint layers to address one of the long-standing questions about cadmium yellow alteration—the roles of cadmium carbonates and cadmium sulphates found in the altered paint layers. These compounds have often been assumed to be photo-oxidation products, but could also be residual starting reagents from an indirect wet process synthesis of CdS. The data presented here allow identifying and mapping the location of cadmium carbonates, cadmium chlorides, cadmium oxalates, cadmium sulphates, and cadmium sulphides in thin sections of altered cadmium yellow paints from The Joy of Life and Matisse's Flower Piece (1906, The Barnes Foundation). Distribution of various cadmium compounds confirms that cadmium carbonates and sulphates are photo-degradation products in The Joy of Life, whereas in Flower Piece, cadmium carbonates appear to have been a [(partially) unreacted] starting reagent for the yellow paint, a role

  8. Technological Characterization of Wall Paintings from the A Mithraic Tomb Dated to 4th-5th Century AD, Gargaresc, Libya

    NASA Astrophysics Data System (ADS)

    Abd El Salam, S.; Maniatis, Y.

    2009-04-01

    The excavations of Gargaresc started in 1965 and were one of the most important archaeological sites in Tripoli because it includes a period of about 500 years starting from the 1stc. AD was and continuing until the 5th century AD. The Mithraic tomb is one of the most important outlying monuments of Oea, 200 yards south of the western end of Gargaresc oasis, on the left of the Tripoli-Zuara road between kilometers 5 & 6. The tomb is cut in an outcrop of soft sandstone. The wall paintings found were symbolic to the religion of that period; which contained a mixture of older religions and Christian, and presented the interaction between the artistic and religious elements of that time. Several optical, chemical and mineralogical methods were applied to identify the materials, composition and technology of the plasters and mortars, as well as, the pigments used in the tomb. These are: -OP: Optical microscopy was used as the initial examination of polished cross-sections to identify the structure and microstratigraphy of the plasters and mortars as well as the painted layers. -MCT: Micro-chemical tests were used to identify the type of the plasters and mortars- calcium aluminium silicate and water-soluble salt to identify sulphates, chlorides, carbonates, nitrites and nitrates. -SM: Standard methods for chemical analysis to identify the quantitative and qualitative nature of the plasters and mortars and their mixture. -SEM & EDS: Analytical Scanning electron microscope with energy dispersive x-ray analysis system to examine the micrmorphology and determine the chemical composition of the plasters, pigments and the inclusions. -XRD: X-ray powder diffraction to identify the mineralogical composition of the plasters, mortars and pigments. On the bases of all the data obtained, it was possible to establish the nature of the plasters, mortars and their binder. The examination and analysis gave a full picture about the materials and the approximate ratio of amount of

  9. Plant cell walls: Protecting the barrier from degradation by microbial enzymes.

    PubMed

    Lagaert, Stijn; Beliën, Tim; Volckaert, Guido

    2009-12-01

    Plant cell walls are predominantly composed of polysaccharides, which are connected in a strong, yet resilient network. They determine the size and shape of plant cells and form the interface between the cell and its often hostile environment. To penetrate the cell wall and thus infect plants, most phytopathogens secrete numerous cell wall degrading enzymes. Conversely, as a first line of defense, plant cell walls contain an array of inhibitors of these enzymes. Scientific knowledge on these inhibitors significantly progressed in the past years and this review is meant to give a comprehensive overview of plant inhibitors against microbial cell wall degrading enzymes and their role in plant protection.

  10. Analytical procedure for characterization of medieval wall-paintings by X-ray fluorescence spectrometry, laser ablation inductively coupled plasma mass spectrometry and Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Syta, Olga; Rozum, Karol; Choińska, Marta; Zielińska, Dobrochna; Żukowska, Grażyna Zofia; Kijowska, Agnieszka; Wagner, Barbara

    2014-11-01

    Analytical procedure for the comprehensive chemical characterization of samples from medieval Nubian wall-paintings by means of portable X-ray fluorescence (pXRF), laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) and Raman spectroscopy (RS) was proposed in this work. The procedure was used for elemental and molecular investigations of samples from archeological excavations in Nubia (modern southern Egypt and northern Sudan). Numerous remains of churches with painted decorations dated back to the 7th-14th century were excavated in the region of medieval kingdoms of Nubia but many aspects of this art and its technology are still unknown. Samples from the selected archeological sites (Faras, Old Dongola and Banganarti) were analyzed in the form of transfers (n = 26), small fragments collected during the excavations (n = 35) and cross sections (n = 15). XRF was used to collect data about elemental composition, LA-ICPMS allowed mapping of selected elements, while RS was used to get the molecular information about the samples. The preliminary results indicated the usefulness of the proposed analytical procedure for distinguishing the substances, from both the surface and sub-surface domains of the wall-paintings. The possibility to identify raw materials from the wall-paintings will be used in the further systematic, archeometric studies devoted to the detailed comparison of various historic Nubian centers.

  11. Cell wall degradation is required for normal starch mobilisation in barley endosperm

    PubMed Central

    Andriotis, Vasilios M. E.; Rejzek, Martin; Barclay, Elaine; Rugen, Michael D.; Field, Robert A.; Smith, Alison M.

    2016-01-01

    Starch degradation in barley endosperm provides carbon for early seedling growth, but the control of this process is poorly understood. We investigated whether endosperm cell wall degradation is an important determinant of the rate of starch degradation. We identified iminosugar inhibitors of enzymes that degrade the cell wall component arabinoxylan. The iminosugar 1,4-dideoxy-1, 4-imino-l-arabinitol (LAB) inhibits arabinoxylan arabinofuranohydrolase (AXAH) but does not inhibit the main starch-degrading enzymes α- and β-amylase and limit dextrinase. AXAH activity in the endosperm appears soon after the onset of germination and resides in dimers putatively containing two isoforms, AXAH1 and AXAH2. Upon grain imbibition, mobilisation of arabinoxylan and starch spreads across the endosperm from the aleurone towards the crease. The front of arabinoxylan degradation precedes that of starch degradation. Incubation of grains with LAB decreases the rate of loss of both arabinoxylan and starch, and retards the spread of both degradation processes across the endosperm. We propose that starch degradation in the endosperm is dependent on cell wall degradation, which permeabilises the walls and thus permits rapid diffusion of amylolytic enzymes. AXAH may be of particular importance in this respect. These results provide new insights into the mobilization of endosperm reserves to support early seedling growth. PMID:27622597

  12. Degradation of barley straw, ryegrass, and alfalfa cell walls by Clostridium longisporum and Ruminococcus albus.

    PubMed

    Varel, V H; Richardson, A J; Stewart, C S

    1989-12-01

    The recently isolated ruminal sporeforming cellulolytic anaerobe Clostridium longisporum B6405 was examined for its ability to degrade barley straw, nonlignified cell walls (mesophyll and epidermis) and lignified cell walls (fiber) of ryegrass, and alfalfa cell walls in comparison with strains of Ruminococcus albus. R. albus strains degraded 20 to 28% of the dry matter in barley straw in 10 days, while the clostridium degraded less than 2%. A combined inoculum of R. albus SY3 and strain B6405 was no more efficient than SY3 alone, and the presence of Methanobacterium smithii PS did not increase the amount of dry matter degraded. In contrast, with alfalfa cell walls as the substrate, the clostridium was twice as active (28% weight loss) as R. albus SY3 (15%). The percentages of dry matter degraded from ryegrass cell walls of mesophyll, epidermis, and fiber for the clostridium were 50, 47, and 32%, respectively, and for R. albus SY3 they were 77, 73, and 63%, respectively. Analyses of the predominant neutral sugars (arabinose, xylose, and glucose) in the plant residues after bacterial attack were consistent with the values for dry matter weight loss. Measurements of the amount of carbon appearing in the fermentation products indicated that R. albus SY3 degraded ryegrass mesophyll cell walls most rapidly, with epidermis and fiber cell walls being degraded at similar rates. Strain B6405 attacked alfalfa cell walls at a rate greater than that of any of the ryegrass substrates. These results indicate an unexpected degree of substrate specificity in the ability of C. longisporum to degrade plant cell wall material.

  13. Signaling role of oligogalacturonides derived during cell wall degradation

    PubMed Central

    Vallarino, José G.; Osorio, Sonia

    2012-01-01

    In addition to the role of the cell wall as a physical barrier against pathogens, some of its constituents, such as pectin-derived oligogalacturonides (OGAs) are essential components to trigger signaling pathways that induce rapid defense responses. Many pathogens directly penetrate the cell wall to access water and nutrients of the plant protoplast, and a rigid cell wall can fend off pathogen attack by forming an impenetrable physical barrier. Thus, cell wall integrity sensing is one mechanism by which plants may detect pathogen attack. Moreover, when the plant-pathogen interaction occurred, OGAs released during cell wall modification can trigger plant defense (e.g., production of reactive oxygen species, production of anti-microbial metabolites and synthesis of pathogenesis-related proteins). This review documents and discusses studies suggesting that OGAs play a dual signaling role during pathogen attack by inducing defense responses and plant architecture adjustment. PMID:22918501

  14. Polysaccharide-degrading Enzymes are Unable to Attack Plant Cell Walls without Prior Action by a “Wall-modifying Enzyme” 1

    PubMed Central

    Karr, Arthur L.; Albersheim, Peter

    1970-01-01

    A study of the degradation of plant cell walls by the mixture of enzymes present in Pectinol R-10 is described. A “wall-modifying enzyme” has been purified from this mixture by a combination of diethylaminoethyl cellulose, Bio Gel P-100, and carboxymethyl cellulose chromatography. Treatment of cell walls with the “wall-modifying enzyme” is shown to be a necessary prerequisite to wall degradation catalyzed by a mixture of polysaccharide-degrading enzymes prepared from Pectinol R-10 or by an α-galactosidase secreted by the pathogenic fungus Colletotrichum lindemuthianum. The action of the “wall-modifying enzyme” on cell walls is shown to result in both a release of water-soluble, 70% ethanol-insoluble polymers and an alteration of the residual cell wall. A purified preparation of the “wall-modifying enzyme” is unable to degrade a wide variety of polysaccharide, glycoside, and peptide substrates. However, the purified preparation of wall-modifying enzyme has a limited ability to degrade polygalacturonic acid. The fact that polygalacturonic acid inhibits the ability of the “wall-modifying enzyme” to affect cell walls suggests that the “wall-modifying enzyme” may be responsible for the limited polygalacturonic acid-degrading activity present in the purified preparation. The importance of a wall-modifying enzyme in developmental processes and in pathogenesis is discussed. PMID:16657425

  15. Sub-surface terahertz imaging through uneven surfaces: visualizing Neolithic wall paintings in Çatalhöyük.

    PubMed

    Walker, Gillian C; Bowen, John W; Matthews, Wendy; Roychowdhury, Soumali; Labaune, Julien; Mourou, Gerard; Menu, Michel; Hodder, Ian; Jackson, J Bianca

    2013-04-08

    Pulsed terahertz imaging is being developed as a technique to image obscured mural paintings. Due to significant advances in terahertz technology, portable systems are now capable of operating in unregulated environments and this has prompted their use on archaeological excavations. August 2011 saw the first use of pulsed terahertz imaging at the archaeological site of Çatalhöyük, Turkey, where mural paintings dating from the Neolithic period are continuously being uncovered by archaeologists. In these particular paintings the paint is applied onto an uneven surface, and then covered by an equally uneven surface. Traditional terahertz data analysis has proven unsuccessful at sub-surface imaging of these paintings due to the effect of these uneven surfaces. For the first time, an image processing technique is presented, based around Gaussian beam-mode coupling, which enables the visualization of the obscured painting.

  16. Analytical imaging studies of the migration of degraded orpiment, realgar, and emerald green pigments in historic paintings and related conservation issues

    SciTech Connect

    Keune, Katrien; Mass, Jennifer; Mehta, Apurva; Church, Jonathan; Meirer, Florian

    2016-04-21

    Yellow orpiment (As2S3) and red–orange realgar (As4S4) photo-degrade and the nineteenth-century pigment emerald green (Cu(C2H3O2)2·3Cu(AsO2)2) degrades into arsenic oxides. Because of their solubility in water, arsenic oxides readily migrate and are found throughout the multi-layered paint system. The widespread arsenic migration has consequences for conservation, and this paper provides better insight into the extent of the problem. Five paint samples containing orpiment, realgar or emerald green pigments deriving from paintings by De Heem (17th C), Van Gogh (19th C), Rousseau (19th C), an unknown 17th C northern European artist and an Austrian painted cupboard (19th C) were investigated using SEM/EDX, imaging ATR-FTIR and arsenic (As) K–edge μ-XANES to obtain the spatial distribution and chemical speciation of arsenic in the paint system. In all of the samples investigated arsenic had migrated throughout the multi-layered paint structure of the art object, from support to varnish. Furthermore, As5+-species were found throughout the entire paint sample. We hypothesize that arsenic trioxide is first formed, dissolves in water, further oxidizes to arsenic pentaoxide, and then reacts with lead, calcium and other ions and is deposited in the paint system as insoluble arsenates. Since the degradation of arsenic pigments such as orpiment, realgar and emerald green occurs through a highly mobile intermediate stage, it not only affects the regions rich in arsenic pigments, but also the entire object, including substrate and top varnish layers. Furthermore, because of this widespread potential for damage, preventing degradation of arsenic pigments should be prioritized and conservators should minimize exposure of objects containing arsenic pigments to strong light, large fluctuations in relative humidity and water-based cleaning agents.

  17. Understanding how the complex molecular architecture of mannan-degrading hydrolases contributes to plant cell wall degradation.

    PubMed

    Zhang, Xiaoyang; Rogowski, Artur; Zhao, Lei; Hahn, Michael G; Avci, Utku; Knox, J Paul; Gilbert, Harry J

    2014-01-24

    Microbial degradation of plant cell walls is a central component of the carbon cycle and is of increasing importance in environmentally significant industries. Plant cell wall-degrading enzymes have a complex molecular architecture consisting of catalytic modules and, frequently, multiple non-catalytic carbohydrate binding modules (CBMs). It is currently unclear whether the specificities of the CBMs or the topology of the catalytic modules are the primary drivers for the specificity of these enzymes against plant cell walls. Here, we have evaluated the relationship between CBM specificity and their capacity to enhance the activity of GH5 and GH26 mannanases and CE2 esterases against intact plant cell walls. The data show that cellulose and mannan binding CBMs have the greatest impact on the removal of mannan from tobacco and Physcomitrella cell walls, respectively. Although the action of the GH5 mannanase was independent of the context of mannan in tobacco cell walls, a significant proportion of the polysaccharide was inaccessible to the GH26 enzyme. The recalcitrant mannan, however, was fully accessible to the GH26 mannanase appended to a cellulose binding CBM. Although CE2 esterases display similar specificities against acetylated substrates in vitro, only CjCE2C was active against acetylated mannan in Physcomitrella. Appending a mannan binding CBM27 to CjCE2C potentiated its activity against Physcomitrella walls, whereas a xylan binding CBM reduced the capacity of esterases to deacetylate xylan in tobacco walls. This work provides insight into the biological significance for the complex array of hydrolytic enzymes expressed by plant cell wall-degrading microorganisms.

  18. Genetic and functional genomic approaches for the study of plant cell wall degradation in Cellvibrio japonicus.

    PubMed

    Gardner, Jeffrey G; Keating, David H

    2012-01-01

    Microbial degradation of plant cell walls is a critical contributor to the global carbon cycle, and enzymes derived from microbes play a key role in the sustainable biofuels industry. Despite its biological and biotechnological importance, relatively little is known about how microbes degrade plant cell walls. Much of this gap in knowledge has resulted from difficulties in extending modern molecular tools to the study of plant cell wall-degrading microbes. The bacterium Cellvibrio japonicus has recently emerged as a powerful model system for the study of microbial plant cell wall degradation. C. japonicus is unique among microbial model systems in that it possesses the ability to carry out the complete degradation of plant cell wall polysaccharides. Furthermore, an extensive array of genetic and molecular tools exists for functional genomic analysis. In this review, we describe progress in the development of methodology for the functional genomic study of plant cell wall degradation by this microbe, and discuss future directions for research. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods. 2. Original paint layer samples.

    PubMed

    Monico, Letizia; Van der Snickt, Geert; Janssens, Koen; De Nolf, Wout; Miliani, Costanza; Dik, Joris; Radepont, Marie; Hendriks, Ella; Geldof, Muriel; Cotte, Marine

    2011-02-15

    The darkening of the original yellow areas painted with the chrome yellow pigment (PbCrO(4), PbCrO(4)·xPbSO(4), or PbCrO(4)·xPbO) is a phenomenon widely observed on several paintings by Vincent van Gogh, such as the famous different versions of Sunflowers. During our previous investigations on artificially aged model samples of lead chromate, we established for the first time that darkening of chrome yellow is caused by reduction of PbCrO(4) to Cr(2)O(3)·2H(2)O (viridian green), likely accompanied by the presence of another Cr(III) compound, such as either Cr(2)(SO(4))(3)·H(2)O or (CH(3)CO(2))(7)Cr(3)(OH)(2) [chromium(III) acetate hydroxide]. In the second part of this work, in order to demonstrate that this reduction phenomenon effectively takes place in real paintings, we study original paint samples from two paintings of V. van Gogh. As with the model samples, in view of the thin superficial alteration layers that are present, high lateral resolution spectroscopic methods that make use of synchrotron radiation (SR), such as microscopic X-ray absorption near edge (μ-XANES) and X-ray fluorescence spectrometry (μ-XRF) were employed. Additionally, μ-Raman and mid-FTIR analyses were carried out to completely characterize the samples. On both paint microsamples, the local presence of reduced Cr was demonstrated by means of μ-XANES point measurements. The presence of Cr(III) was revealed in specific areas, in some cases correlated to the presence of Ba(sulfate) and/or to that of aluminum silicate compounds.

  20. Study by micro-Raman spectroscopy of wall paints (external parts and cross-sections) from reales alcazares of Seville (Spain)

    NASA Astrophysics Data System (ADS)

    Perez-Rodriguez, José Luis; Centeno, Miguel Angel; Robador, María Dolores; Siguenza, Belinda; Durán, Adrián

    2013-04-01

    The Reales Alcazares of Sevilla was originally builded by the Arabic in the year 913. The Mudejar Palace was built by Christian King Pedro I between 1364 and 1366. At the end of XV century the Catholic Kings, Isabel and Fernando made important transformations especially in the Mudejar Palace. Recently, wall paints from Catholic Kings periods were found during works of conservations in the first floor of the Palace. The study of these paints by non-destructive techniques was considered of great interest in order to determine the technology of manufacture and the originality of the artwork. The main objective of this work was to apply the Raman spectroscopy technique on the surface of the wall and on the different layers of the cross-sections prepared in order to characterize the pigments and the plaster present in these wall paints. Little information was obtained using a portable Raman spectrometer. In this case the dispersive integrated Horiba Jobin-Yvon LabRaman HR800 system was employed. Small samples of black, red, yellow, white and green colour were taken from the artwork. The surface of the samples were directly studed by the Raman spectroscopy instrument using red (785 nm) and green (522 nm) lasers, similarly to non-invasive experimental technique. This technique showed the presence of gypsum (SO4Ca.2H2O) and calcite (CaCO3) in all the studied samples However, the pigments responsible of different colours were not detected. The surface of these wall paints was covered with gypsum and calcite due to contamination. These mineras were also characterized by XRD and SEM-EDX. The presence of these compounds and the heterogeneous surface did not permit the characterization of the pigments responsible of the colour. In order to better characterization of the pigments and plaster used the study was carried out on cross-sections. The black colour was performed using carbon black. Two different red layers were detected one constituted by cinnabar and lead carbonate and

  1. Rumen Bacterial Degradation of Forage Cell Walls Investigated by Electron Microscopy

    PubMed Central

    Akin, Danny E.; Amos, Henry E.

    1975-01-01

    The association of rumen bacteria with specific leaf tissues of the forage grass Kentucky-31 tall fescue (Festuca arundinacea Schreb.) during in vitro degradation was investigated by transmission and scanning electron microscopy. Examination of degraded leaf cross-sections revealed differential rates of tissue degradation in that the cell walls of the mesophyll and pholem were degraded prior to those of the outer bundle sheath and epidermis. Rumen bacteria appeared to degrade the mesophyll, in some cases, and phloem without prior attachment to the plant cell walls. The degradation of bundle sheath and epidermal cell walls appeared to be preceded by attachment of bacteria to the plant cell wall. Ultrastructural features apparently involved in the adhesion of large cocci to plant cells were observed by transmission and scanning electron microscopy. The physical association between plant and rumen bacterial cells during degradation apparently varies with tissue types. Bacterial attachment, by extracellular features in some microorganisms, is required prior to degradation of the more resistant tissues. Images PMID:16350017

  2. Characterization of a degraded cadmium yellow (CdS) pigment in an oil painting by means of synchrotron radiation based X-ray techniques.

    PubMed

    Van der Snickt, Geert; Dik, Joris; Cotte, Marine; Janssens, Koen; Jaroszewicz, Jakub; De Nolf, Wout; Groenewegen, Jasper; Van der Loeff, Luuk

    2009-04-01

    On several paintings of James Ensor (1860-1949), a gradual fading of originally bright yellow areas, painted with the pigment cadmium yellow (CdS), is observed. Additionally, in some areas exposed to light, the formation of small white-colored globules on top of the original paint surface is observed. In this paper the chemical transformation leading to the color change and to the formation of the globules is elucidated. Microscopic X-ray absorption near-edge spectroscopy (mu-XANES) experiments show that sulfur, originally present in sulfidic form (S(2-)), is oxidized during the transformation to the sulfate form (S(6+)). Upon formation (at or immediately below the surface), the highly soluble cadmium sulfate is assumed to be transported to the surface in solution and reprecipitates there, forming the whitish globules. The presence of cadmium sulfate (CdSO(4).2H(2)O) and ammonium cadmium sulfate [(NH(4))(2)Cd(SO(4))(2)] at the surface is confirmed by microscopic X-ray diffraction measurements, where the latter salt is suspected to result from a secondary reaction of cadmium sulfate with ammonia. Measurements performed on cross sections reveal that the oxidation front has penetrated into the yellow paint down to ca. 1-2 microm. The morphology and elemental distribution of the paint and degradation product were examined by means of scanning electron microscopy equipped with an energy-dispersive spectrometer (SEM-EDS) and synchrotron radiation based micro-X-ray fluorescence spectrometry (SR micro-XRF). In addition, ultraviolet-induced visible fluorescence photography (UIVFP) revealed itself to be a straightforward technique for documenting the occurrence of this specific kind of degradation on a macroscale by painting conservators.

  3. Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods. Part 5. Effects of nonoriginal surface coatings into the nature and distribution of chromium and sulfur species in chrome yellow paints.

    PubMed

    Monico, Letizia; Janssens, Koen; Vanmeert, Frederik; Cotte, Marine; Brunetti, Brunetto Giovanni; Van der Snickt, Geert; Leeuwestein, Margje; Salvant Plisson, Johanna; Menu, Michel; Miliani, Costanza

    2014-11-04

    investigation of aged model paints in the last Part 4 paper, in this study we aim to characterize a possible relation between the chemical composition of the coating and the chrome yellow degradation pathways by studying photochemically aged model samples covered with a dammar varnish contaminated with sulfide and sulfate salts. Cr speciation results did not show any evidence of the active role of the varnish and added S species on the reduction process of chrome yellows.

  4. A multi-analytical approach for the study of the pigments used in the wall paintings from a building complex on the Caelian Hill (Rome)

    NASA Astrophysics Data System (ADS)

    Fermo, Paola; Piazzalunga, Andrea; de Vos, Mariette; Andreoli, Martina

    2013-12-01

    In the present study, shards from Roman wall paintings (from the end of the first century to the fourth century A.D.) decorating the domus below the Basilica of SS. John and Paul on the Caelian Hill (Rome), were analyzed in order to identify the pigments used. The analytical techniques employed for the characterization of the pigments were the scanning electron microscope coupled with an energy dispersive spectrometer (SEM-EDS) and infrared spectroscopy (ATR and micro ATR). While SEM-EDS allowed to perform a qualitative analysis of the material, by FT-IR chemical species have been identified. The pigments identified were those mentioned in the literature for the Imperial Roman fresco painting: different types of ochre (yellow and red), mixtures containing lead, green earths and precious pigments such as cinnabar and Egyptian blue. They were often used as mixtures and the use of the most valuable pigments (cinnabar and Egyptian blue) were found in the most ancient rooms.

  5. Micro-attenuated total reflection spectral imaging in archaeology: application to Maya paint and plaster wall decorations.

    PubMed

    Goodall, Rosemary A; Hall, Jay; Sharer, Robert J; Traxler, Loa; Rintoul, Llew; Fredericks, Peter M

    2008-01-01

    Fourier transform infrared (FT-IR) attenuated total reflection (ATR) imaging has been successfully used to identify individual mineral components of ancient Maya paint. The high spatial resolution of a micro FT-IR-ATR system in combination with a focal plane array detector has allowed individual particles in the paint to be resolved and identified from their spectra. This system has been used in combination with micro-Raman spectroscopy to characterize the paint, which was found to be a mixture of hematite and silicate particles with minor amounts of calcite, carbon, and magnetite particles in a sub-micrometer hematite and calcite matrix. The underlying stucco was also investigated and found to be a combination of calcite with fine carbon particles, making a dark sub-ground for the paint.

  6. Identification of polysaccharide hydrolases involved in autolytic degradation of Zea cell walls

    SciTech Connect

    Nock, L.P.; Smith, C.J. )

    1987-08-01

    Cell walls of Zea mays (cv L.G.11) seedlings labeled with {sup 14}C were treated with {alpha}-amylase from Bacillus subtilis to remove starch and mixed linkage glucans. These walls released arabinose, xylose, galactose, and galacturonic acid in addition to glucose when they were allowed to autolyze. Methylation analysis was performed on samples of wall which had been incubated autolytically and the results indicated that degradation of the major polymer of the wall, the glucoarabinoxylan, had occurred. A number of glycanases could be dissociated from the wall by use of 3 M LiCL. The proteins which were released were found to contain a number of exoglycosidase activities in addition to being effective in degrading the polysaccharide substrates, araban, xylan, galactan, laminarin, mannan, and polygalacturonic acid. The effects of these enzymes on the wall during autolysis appear to result from endo-activity in addition to exo-activity. The structural changes that occurred in the cell walls during autolysis were found to be related to the changes previously found to occur in cell walls during auxin induced extension.

  7. A Cell Wall-degrading Endopolygalacturonase Secreted by Colletotrichum lindemuthianum.

    PubMed

    English, P D; Maglothin, A; Keegstra, K; Albersheim, P

    1972-03-01

    Cultures of Colletotrichum lindemuthianum (Saccardo and Magnus) Scribner have been induced to secrete an endopolygalacturonase (polygalacturonide glycanohydrolase EC3.2. 1.15). This enzyme has been brought to a high state of purity by ion exchange, gel filtration, and agarose affinity chromatography. The enzyme has optimal activity at pH 5, has an apparent molecular weight as determined by gel filtration of about 70,000, and prefers polygalacturonic acid to pectin as its substrate. The enzyme, while hydrolyzing only 1% of the glycosidic bonds, reduces the viscosity of a polygalacturonic solution by 50%. Nevertheless, the initial as well as the final products of polygalacturonic acid hydrolysis are predominantly tri- and digalacturonic acid and, to a lesser extent, monogalacturonic acid. The purified enzyme catalyzes the removal of about 80% of the galacturonic acid residues of cell walls isolated from suspension-cultured sycamore cells (Acer pseudoplatanus) as well as from the walls isolated from 8-day-old Red Kidney bean (Phaseolus vulgaris) hypocotyls.

  8. Regulation of Aspergillus genes encoding plant cell wall polysaccharide-degrading enzymes; relevance for industrial production.

    PubMed

    de Vries, R P

    2003-03-01

    The genus Aspergillus is widely used for the production of plant cell wall polysaccharide-degrading enzymes. The range of enzymes purified from these fungi covers nearly every function required for the complete degradation of cellulose, xyloglucan, xylan, galacto(gluco)mannan and pectin. This paper describes the Aspergillus enzymes involved in the degradation of these polysaccharides and discusses the regulatory systems involved in the expression of the genes encoding these proteins. The latter is of major importance in the large-scale production of these enzymes for industrial applications.

  9. Use of mid-infrared fiber-optic reflectance spectroscopy (FORS) to evaluate efficacy of nanostructured systems in wall painting conservation

    NASA Astrophysics Data System (ADS)

    Rosenzweig, B.; Carretti, E.; Picollo, M.; Baglioni, P.; Dei, L.

    2006-06-01

    Mid-infrared fiber-optic reflectance spectroscopy (Mid-IR FORS), a sensitive, non-invasive technique for determining chemicals present on a surface, has been used to test efficacy of oil-in-water microemulsions and micellar solutions in cleaning of painted surfaces. The target of the application of these innovative nanostructured systems was the selective removal of an undesired polymeric layer from a fresco surface. The experiments were carried out by first coating frosted glass slides and painted mortar simulating a real fresco with four acrylic and vinyl polymer varnishes commonly used in wall painting restoration. Spectra of the samples were then collected by means of microreflectance single-beam infrared spectroscopy and Mid-IR FORS before and after the application of the aqueous dispersed systems based cleaning agents. Sharp, strong peaks due to the stretching of the estereous C=O bond of the polymers in a wavelength range between 1730 and 1750 cm-1 were used as marker for the presence of these organic materials. Through Mid-IR FORS semiquantitative spectroscopy, the efficiency of the treatment has been clearly demonstrated, indicating that the nanotechnology approach represents a new, safe, and very efficient way of removing aged polymers from fresco surfaces.

  10. Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of synchrotron X-ray spectromicroscopy and related methods. 1. Artificially aged model samples.

    PubMed

    Monico, Letizia; Van der Snickt, Geert; Janssens, Koen; De Nolf, Wout; Miliani, Costanza; Verbeeck, Johan; Tian, He; Tan, Haiyan; Dik, Joris; Radepont, Marie; Cotte, Marine

    2011-02-15

    On several paintings by artists of the end of the 19th century and the beginning of the 20th Century a darkening of the original yellow areas, painted with the chrome yellow pigment (PbCrO(4), PbCrO(4)·xPbSO(4), or PbCrO(4)·xPbO) is observed. The most famous of these are the various Sunflowers paintings Vincent van Gogh made during his career. In the first part of this work, we attempt to elucidate the degradation process of chrome yellow by studying artificially aged model samples. In view of the very thin (1-3 μm) alteration layers that are formed, high lateral resolution spectroscopic methods such as microscopic X-ray absorption near edge (μ-XANES), X-ray fluorescence spectrometry (μ-XRF), and electron energy loss spectrometry (EELS) were employed. Some of these use synchrotron radiation (SR). Additionally, microscopic SR X-ray diffraction (SR μ-XRD), μ-Raman, and mid-FTIR spectroscopy were employed to completely characterize the samples. The formation of Cr(III) compounds at the surface of the chrome yellow paint layers is particularly observed in one aged model sample taken from a historic paint tube (ca. 1914). About two-thirds of the chromium that is present at the surface has reduced from the hexavalent to the trivalent state. The EELS and μ-XANES spectra are consistent with the presence of Cr(2)O(3)·2H(2)O (viridian). Moreover, as demonstrated by μ-XANES, the presence of another Cr(III) compound, such as either Cr(2)(SO(4))(3)·H(2)O or (CH(3)CO(2))(7)Cr(3)(OH)(2) [chromium(III) acetate hydroxide], is likely.

  11. Microorganisms and methods for degrading plant cell walls and complex hydrocarbons

    SciTech Connect

    Polne-Fuller, M.

    1991-09-24

    This patent describes a biologically pure multinucleated marine amoeba having the identifying characteristics of ATCC 40319. The amoeba being capable of digesting algal cell walls and having the further capacity to degrade paraffin, wax, polyethylene, polypropylene, polyvinyl chloride polyvinylidene di-chloride and mixtures thereof.

  12. Triggering of autolytic cell wall degradation in Escherichia coli by beta-lactam antibiotics.

    PubMed Central

    Kitano, K; Tomasz, A

    1979-01-01

    A biochemical method was developed to quantitatively compare the effectiveness of beta-lactams in triggering murein degradation (autolysin activity) in Escherichia coli. Bacteria prelabeled in their cell walls with radioactive diaminopimelic acid in growth medium were exposed for 10 min to the antibiotics at the appropriate minimal growth inhibitory concentrations and at multiples of these values, and the rate of cell wall degradation was followed during subsequent penicillin-binding protein (PBP)-1 were the most effective triggers of autolytic wall degradation; beta-lactams selective for PBP-2 were the poorest; and antibiotics preferentially binding to PBP-3 showed intermediate activities. The relative effectiveness of beta-lactams in autolysin triggering was found to parallel the effectiveness of the same drugs in causing rapid loss of viability, culture lysis, and spheroplast formation. Autolysin triggering was suppressed by inhibitors of protein and ribonucleic acid biosynthesis but not by inhibitors of deoxyribonucleic acid synthesis. The beta-lactam-induced cell wall degradation did not seem to involve a direct stimulation of enzyme activity or synthesis of new enzyme molecules, and murein sacculi isolated from cells that had been preexposed to a triggering dose of beta-lactam treatment exhibited the same sensitivity to crude, homologous autolysins as sacculi prepared from untreated control bacteria. On the basis of these observations, mechanisms are considered for the triggering of E. coli autolysins and for the role of autolytic activity in bacterial spheroplast formation, lysis, and death. Images PMID:93877

  13. Arsenal of plant cell wall degrading enzymes reflects host preference among plant pathogenic fungi

    USDA-ARS?s Scientific Manuscript database

    Discovery and development of novel plant cell wall degrading enzymes is a key step towards more efficient depolymerization of polysaccharides to fermentable sugars for production of liquid transportation biofuels and other bioproducts. The industrial fungus Trichoderma reesei is known to be highly c...

  14. Chemical composition and cell wall polysaccharide degradability of pith and rind tissues from mature maize internodes

    USDA-ARS?s Scientific Manuscript database

    This study was undertaken to identify tissue-specific biochemical traits that may be targeted in breeding programs for improving forage digestibility. We compared cell wall chemical composition and 24- and 96-h in vitro degradabilities in separated pith and rind tissues of the fourth above-ground in...

  15. Chemical composition and cell wall polysaccharide degradability of pith and rind tissues from mature maize internodes

    USDA-ARS?s Scientific Manuscript database

    Our study was undertaken to identify tissue-specific biochemical traits that may be targeted in breeding programs for improving forage digestibility. We compared cell wall chemical composition and 24- and 96-h in vitro degradabilities in separated pith and rind tissues from six maize inbred lines. A...

  16. NADPH oxidase-dependent degradation of single-walled carbon nanotubes in macrophages.

    PubMed

    Ding, Yun; Tian, Rong; Yang, Zhen; Chen, Jianfa; Lu, Naihao

    2017-01-01

    Previous studies have shown that carboxylated single-walled carbon nanotubes (SWCNTs) could be oxidatively biodegraded by neutrophil myeloperoxidase (MPO) and peroxynitrite (ONOO(-)). However, the biodegradation mechanism of nanotubes in macrophages has not been explored enough. Here, we showed that both MPO and ONOO(-) could effectively oxidize SWCNTs to generate shorter and oxidative nanotubes in vitro. SWCNTs were significantly degraded in zymosan-stimulated macrophages, and the degradation mechanism was dependent on MPO and ONOO(-)-driven oxidative pathways of activated macrophages, where NADPH oxidase was found to be a major determinant of the biodegradation process. Moreover, the functionalization of IgG to SWCNTs could stimulate MPO release and ONOO(-) formation in macrophages, thereby creating the conditions favorable for degradation of nanotubes and subsequently contributing to the higher degradation degree of IgG-coated SWCNTs. Therefore, our discovery of NADPH oxidase-dependent SWCNTs degradation in activated macrophages will open new opportunities for the regulation of SWCNTs fate in vivo.

  17. Effects of X-irradiation on artificial blood vessel wall degradation by invasive tumor cells

    SciTech Connect

    Heisel, M.A.; Laug, W.E.; Stowe, S.M.; Jones, P.A.

    1984-06-01

    Artificial vessel wall cultures, constructed by growing arterial endothelial cells on preformed layers of rat smooth muscle cells, were used to evaluate the effects of X-irradiation on tumor cell-induced tissue degradation. Bovine endothelial cells had radiation sensitivities similar to those of rat smooth muscle cells. Preirradiation of smooth muscle cells, before the addition of human fibrosarcoma (HT 1080) cells, did not increase the rate of degradation and destruction by the invasive cells. However, the degradation rate was decreased if the cultures were irradiated after the addition of HT 1080 cells. The presence of bovine endothelial cells markedly inhibited the destructive abilities of fibrosarcoma cells, but preirradiation of artificial vessel walls substantially decreased their capabilities to resist HT 1080-induced lysis. These findings suggest that the abilities of blood vessels to limit extravasation may be compromised by ionizing radiation.

  18. Selective degradation of the recalcitrant cell wall of Scenedesmus quadricauda CASA CC202.

    PubMed

    Reshma, Ragini; Arumugam, Muthu

    2017-07-06

    An eco-friendly cell wall digestion strategy was developed to enhance the availability of nutritionally important bio molecules of edible microalgae and exploit them for cloning, transformation, and expression of therapeutic proteins. Microalgae are the source for many nutritionally important bioactive compounds and potential drugs. Even though edible microalgae are rich in nutraceutical, bioavailability of all these molecules is very less due to their rigid recalcitrant cell wall. For example, the cell wall of Scenedesmus quadricauda CASA CC202 is made up of three layers comprising of rigid outer pectin and inner cellulosic layer separated by a thin middle layer. In the present investigation, a comprehensive method has been developed for the selective degradation of S. quadricauda CASA CC202 cell wall, by employing both mechanical and enzymatic treatments. The efficiency of cell wall removal was evaluated by measuring total reducing sugar (TRS), tannic acid-ferric chloride staining, calcoflour white staining, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) analysis. It was confirmed that the yield of TRS increased from 129.82 mg/g in 14 h from pectinase treatment alone to 352.44 mg/g by combined sonication and enzymatic treatment within 12 h. As a result, the combination method was found to be effective for the selective degradation of S. quadricauda CASA CC202 cell wall. This study will form a base for our future works, where this will help to enhance the digestibility and availability of nutraceutically important proteins.

  19. PAINT SHOP, FIRST FLOOR, NORTHEAST CORNER OFFICE INTERIOR, LOOKING WEST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PAINT SHOP, FIRST FLOOR, NORTHEAST CORNER OFFICE INTERIOR, LOOKING WEST. PROJECTING WALLS WITH INFILLED ARCHES WERE PART OF ONE PAINTING BOOTH IN ORIGINAL STRUCTURE. - Southern Pacific, Sacramento Shops, Paint Shop, 111 I Street, Sacramento, Sacramento County, CA

  20. Identification of vessel wall degradation in ascending thoracic aortic aneurysms with OCT

    PubMed Central

    Real, Eusebio; Val-Bernal, José Fernando; Revuelta, José M.; Pontón, Alejandro; Díez, Marta Calvo; Mayorga, Marta; López-Higuera, José M.; Conde, Olga M.

    2014-01-01

    Degradation of the wall of human ascending thoracic aorta has been assessed through Optical Coherence Tomography (OCT). OCT images of the media layer of the aortic wall exhibit micro-structure degradation in case of diseased aortas from aneurysmal vessels. The OCT indicator of degradation depends on the dimension of areas of the media layer where backscattered reflectivity becomes smaller due to a disorder on the morphology of elastin, collagen and smooth muscle cells (SMCs). Efficient pre-processing of the OCT images is required to accurately extract the dimension of degraded areas after an optimized thresholding procedure. OCT results have been validated against conventional histological analysis. The OCT qualitative assessment has achieved a pair sensitivity-specificity of 100%-91.6% in low-high degradation discrimination when a threshold of 4965.88µm2 is selected. This threshold suggests to have physiological meaning. The OCT quantitative evaluation of degradation achieves a correlation of 0.736 between the OCT indicator and the histological score. This in-vitro study can be transferred to the clinical scenario to provide an intraoperative assessment tool to guide cardiovascular surgeons in open repair interventions. PMID:25426332

  1. Reaction of Pb(II) and Zn(II) with Ethyl Linoleate To Form Structured Hybrid Inorganic–Organic Complexes: A Model for Degradation in Historic Paint Films

    DOE PAGES

    MacDonald, Margaret G.; Palmer, Michael R.; Suchomel, Matthew R.; ...

    2016-09-07

    To investigate soap formation in drying oils in historic paints, the reaction between metal acetates (K+, Zn2+, Pb2+) and ethyl linoleate (EL) was studied using optical microscopy, X-ray powder diffraction, and electron microscopy. Pb(II) and Zn(II) react rapidly with EL to form highly structured, spherulitic, luminescent crystallites that aggregate. Evidence from Fourier transform infrared (FTIR) and scanning electron microscopy/energy dispersive X-ray analysis and high-resolution synchrotron powder X-ray diffraction indicates that these are organic-inorganic hybrid complexes or coordination polymers. FTIR absorbance peaks at ca. 1540 cm-1 for Pb(II) and ca. 1580 cm-1 for Zn(II) are consistent with the formation of carboxylatemore » complexes. The complexes formed offer insight into the degradation processes observed in oil paint films, suggesting that soap formation is rapid when metal ions are solubilized and can occur with unsaturated fatty acids that are present in fresh oils. Finally, these complexes may account for the atypical luminescence observed in lead-containing cured oil paint films.« less

  2. Reaction of Pb(II) and Zn(II) with Ethyl Linoleate To Form Structured Hybrid Inorganic–Organic Complexes: A Model for Degradation in Historic Paint Films

    SciTech Connect

    MacDonald, Margaret G.; Palmer, Michael R.; Suchomel, Matthew R.; Berrie, Barbara H.

    2016-09-23

    To investigate soap formation in drying oils in historic paints, the reaction between metal acetates (K+, Zn2+, Pb2+) and ethyl linoleate (EL) was studied using optical microscopy, X-ray powder diffraction, and electron microscopy. Pb(II) and Zn(II) react rapidly with EL to form highly structured, spherulitic, luminescent crystallites that aggregate. Evidence from Fourier transform infrared (FTIR) and scanning electron microscopy/energy dispersive X-ray analysis and high-resolution synchrotron powder X-ray diffraction indicates that these are organic–inorganic hybrid complexes or coordination polymers. FTIR absorbance peaks at ca. 1540 cm–1 for Pb(II) and ca. 1580 cm–1 for Zn(II) are consistent with the formation of carboxylate complexes. The complexes formed offer insight into the degradation processes observed in oil paint films, suggesting that soap formation is rapid when metal ions are solubilized and can occur with unsaturated fatty acids that are present in fresh oils. These complexes may account for the atypical luminescence observed in lead-containing cured oil paint films.

  3. Optical coherence tomography assessment of vessel wall degradation in thoracic aortic aneurysms

    NASA Astrophysics Data System (ADS)

    Real, Eusebio; Eguizabal, Alma; Pontón, Alejandro; Díez, Marta Calvo; Fernando Val-Bernal, José; Mayorga, Marta; Revuelta, José M.; López-Higuera, José M.; Conde, Olga M.

    2013-12-01

    Optical coherence tomography images of human thoracic aorta from aneurysms reveal elastin disorders and smooth muscle cell alterations when visualizing the media layer of the aortic wall. These disorders can be employed as indicators for wall degradation and, therefore, become a hallmark for diagnosis of risk of aneurysm under intraoperative conditions. Two approaches are followed to evaluate this risk: the analysis of the reflectivity decay along the penetration depth and the textural analysis of a two-dimensional spatial distribution of the aortic wall backscattering. Both techniques require preprocessing stages for the identification of the air-sample interface and for the segmentation of the media layer. Results show that the alterations in the media layer of the aortic wall are better highlighted when the textural approach is considered and also agree with a semiquantitative histopathological grading that assesses the degree of wall degradation. The correlation of the co-occurrence matrix attains a sensitivity of 0.906 and specificity of 0.864 when aneurysm automatic diagnosis is evaluated with a receiver operating characteristic curve.

  4. Time-Resolved Visualization of Görtler Vortices in a Pulsed Convex Wall Jet using Fast Pressure-Sensitive Paint

    NASA Astrophysics Data System (ADS)

    Gregory, James; Danon, Ron; Greenblatt, David

    2015-11-01

    The time-resolved formation and structure of Görtler vortices in a pulsed convex wall jet are studied in this work. While the presence of Görtler vortices in laminar boundary layers on concave surfaces can be clearly observed, their presence in wall jets flowing over convex surfaces is difficult to discern due to transition to turbulence in the outer part of the jet. This work employed fast-response pressure-sensitive paint (PSP), which has a documented flat frequency response greater than 5 kHz, to visualize the time-resolved formation of the wall jet and the details of the Görtler vortices. The radius of curvature of the wall jet was 8 cm, and the Reynolds number (based on slot height and jet exit velocity) was varied between 5 ×102 and 4 ×104 . The characteristic spanwise wavelength of the vortices was studied as a function of jet Reynolds number. Furthermore, as the Reynolds number was increased, various secondary instabilities were observed that led to laminar-turbulent transition. Funding provided by the U.S. Fulbright Scholar Program.

  5. [Research on biocompatibility and in vivo degradation of biodegradable chest wall prosthesis materials in experimental animals].

    PubMed

    Gong, Zhiyun; Xu, Zhifei; Qin, Xiong

    2007-08-01

    To evaluate the biocompatibility and in vivo degradation of novel chest wall prosthesis materials and provide some data for their clinical application. According to the standard for the biological evaluation of the medical devices, several tests were performed to evaluate the tissue toxic effects induced by polydioxanone (Group A), chitosan (Group B), and hydroxyapitite/collagen (Group C), which were tested as component materials of the chest wall prosthesis. In the hemolysis test, 0.2 ml of the anticoagulant rabbit blood was added to the component materials and the normal saline (negative control) and to the distilled water (positive control). Five samples were made in each group. Absorbency was measured and the hemolysis rate was determined. In the acute systemic toxicity test, 20 mice were randomly divided into 4 groups (Groups A, B and C, and the normal saline group, n=5). The leaching liquid (50 ml/kg) was injected through the caudal vein, which was observed at 24, 48 and 72 hours. In the pyrogen test, 12 rabbits were randomly divided into 4 groups (Groups A, B, C and the normal saline group, n=3) the leaching liquid(10 ml/kg) was injected through the ear vein, and the body temperature was recorded within 3 hours. In the in vivo degradable test, the component materials (10 mm x 10 mm) were implanted in 12 rabbits at 2, 4, 8, 12, 16 and 24 weeks, respectively, after operation. Two rabbits were sacrificed for the macroscopic and the microscopic examinations. The chest wall component materials had no hemolytic reaction, no acute systemic toxicity, and no pyrogen reaction. The results demonstrated that the implanted materials had only a mild inflammatory reaction during the early days of the grafting, which subsided gradually. There was no tissue denaturation, necrosis or pathological hyperplasia when the prosthesis materials were degraded. The degradable materials of the chest wall prosthesis have a good biocompatibility and a great biological safety though their

  6. Plant cell wall degradation by saprophytic Bacillus subtilis strains: gene clusters responsible for rhamnogalacturonan depolymerization.

    PubMed

    Ochiai, Akihito; Itoh, Takafumi; Kawamata, Akiko; Hashimoto, Wataru; Murata, Kousaku

    2007-06-01

    Plant cell wall degradation is a premier event when Bacillus subtilis, a typical saprophytic bacterium, invades plants. Here we show the degradation system of rhamnogalacturonan type I (RG-I), a component of pectin from the plant cell wall, in B. subtilis strain 168. Strain 168 cells showed a significant growth on plant cell wall polysaccharides such as pectin, polygalacturonan, and RG-I as a carbon source. DNA microarray analysis indicated that three gene clusters (yesOPQRSTUVWXYZ, ytePQRST, and ybcMOPST-ybdABDE) are inducibly expressed in strain 168 cells grown on RG-I. Cells of an industrially important bacterium, B. subtilis strain natto, fermenting soybeans also express the gene cluster including the yes series during the assimilation of soybean used as a carbon source. Among proteins encoded in the yes cluster, YesW and YesX were found to be novel types of RG lyases releasing disaccharide from RG-I. Genetic and enzymatic properties of YesW and YesX suggest that strain 168 cells secrete YesW, which catalyzes the initial cleavage of the RG-I main chain, and the resultant oligosaccharides are converted to disaccharides through the extracellular exotype YesX reaction. The disaccharide is finally degraded into its constituent monosaccharides through the reaction of intracellular unsaturated galacturonyl hydrolases YesR and YteR. This enzymatic route for RG-I degradation in strain 168 differs significantly from that in plant-pathogenic fungus Aspergillus aculeatus. This is, to our knowledge, the first report on the bacterial system for complete RG-I main chain degradation.

  7. Plant Cell Wall Degradation by Saprophytic Bacillus subtilis Strains: Gene Clusters Responsible for Rhamnogalacturonan Depolymerization▿

    PubMed Central

    Ochiai, Akihito; Itoh, Takafumi; Kawamata, Akiko; Hashimoto, Wataru; Murata, Kousaku

    2007-01-01

    Plant cell wall degradation is a premier event when Bacillus subtilis, a typical saprophytic bacterium, invades plants. Here we show the degradation system of rhamnogalacturonan type I (RG-I), a component of pectin from the plant cell wall, in B. subtilis strain 168. Strain 168 cells showed a significant growth on plant cell wall polysaccharides such as pectin, polygalacturonan, and RG-I as a carbon source. DNA microarray analysis indicated that three gene clusters (yesOPQRSTUVWXYZ, ytePQRST, and ybcMOPST-ybdABDE) are inducibly expressed in strain 168 cells grown on RG-I. Cells of an industrially important bacterium, B. subtilis strain natto, fermenting soybeans also express the gene cluster including the yes series during the assimilation of soybean used as a carbon source. Among proteins encoded in the yes cluster, YesW and YesX were found to be novel types of RG lyases releasing disaccharide from RG-I. Genetic and enzymatic properties of YesW and YesX suggest that strain 168 cells secrete YesW, which catalyzes the initial cleavage of the RG-I main chain, and the resultant oligosaccharides are converted to disaccharides through the extracellular exotype YesX reaction. The disaccharide is finally degraded into its constituent monosaccharides through the reaction of intracellular unsaturated galacturonyl hydrolases YesR and YteR. This enzymatic route for RG-I degradation in strain 168 differs significantly from that in plant-pathogenic fungus Aspergillus aculeatus. This is, to our knowledge, the first report on the bacterial system for complete RG-I main chain degradation. PMID:17449691

  8. Plant cell wall-degrading enzymes and their secretion in plant-pathogenic fungi.

    PubMed

    Kubicek, Christian P; Starr, Trevor L; Glass, N Louise

    2014-01-01

    Approximately a tenth of all described fungal species can cause diseases in plants. A common feature of this process is the necessity to pass through the plant cell wall, an important barrier against pathogen attack. To this end, fungi possess a diverse array of secreted enzymes to depolymerize the main structural polysaccharide components of the plant cell wall, i.e., cellulose, hemicellulose, and pectin. Recent advances in genomic and systems-level studies have begun to unravel this diversity and have pinpointed cell wall-degrading enzyme (CWDE) families that are specifically present or enhanced in plant-pathogenic fungi. In this review, we discuss differences between the CWDE arsenal of plant-pathogenic and non-plant-pathogenic fungi, highlight the importance of individual enzyme families for pathogenesis, illustrate the secretory pathway that transports CWDEs out of the fungal cell, and report the transcriptional regulation of expression of CWDE genes in both saprophytic and phytopathogenic fungi.

  9. Recovering data from noisy fringe patterns from a portable digital speckle pattern interferometer for in-situ inspection of painting hanging on the wall

    NASA Astrophysics Data System (ADS)

    Memmolo, P.; Arena, G.; Paturzo, M.; Fatigati, G.; Grilli, M.; Pezzati, L.; Ferraro, Pietro

    2015-03-01

    We report on a method for recovering data from a simple portable Digital Speckle Pattern Interferometer intended for utilization outside of laboratory conditions, without anti-vibration devices. We used the system for monitoring the structural behavior of a painting on wood, hanging on a wall. In such a situation, fringes, produced by the object displacements, were affected by random distortions caused by environment noise. However a satisfactory number of undistorted, or barely distorted, fringe patterns were found and utilized for processing. We performed fast continuous acquisitions of consecutive interferograms, picking usable fringe patterns out of a large amount of recorded frames. This is the crucial task in the measurement procedure. For this purpose we developed a software routine, based on jointly analysis of both spectral content and fringe image sharpne ss, as selection rule. From the selected frames, by using a simple approach based on Hilbert Transform and Phase Unwrapping, via MAx-flow (PUMA) algorithm, we were able to evaluate the painting whole structure deformations, caused by environmental thermo-hygrometric fluctuations.

  10. Ochre-differentiation through micro-Raman and micro-FTIR spectroscopies: application on wall paintings at Meteora and Mount Athos, Greece.

    PubMed

    Bikiaris, D; Daniilia Sister; Sotiropoulou, S; Katsimbiri, O; Pavlidou, E; Moutsatsou, A P; Chryssoulakis, Y

    2000-01-01

    The most widely-used inorganic pigments of Byzantine and post-Byzantine hagiography are earth pigments called ochres such as, red and yellow ochres, limonite, goethite, raw and burnt sienna, caput mortuum and hematite. The present experimental work proposes a technique of differentiation that allows one to distinguish among all the different kinds of iron oxides, thereby providing a better understanding of the painting technique used on portable icons and wall paintings. The ratios between the main spectroscopic peaks, attributable to the major components usually present in ochres, were calculated and compared, one against the another, from the spectra obtained through micro-Raman spectroscopy. Elementary composition is also revealed through a scanning electron microscopy (SEM) analysis. The possibility for detailed study on a particular Byzantine ochre palette can thus be performed based on the small differences in its nature and composition. These differences can first be observed and then measured among all of the natural earth pigments, through microRaman and microFTIR spectroscopies.

  11. Ochre-differentiation through micro-Raman and micro-FTIR spectroscopies: application on wall paintings at Meteora and Mount Athos, Greece

    NASA Astrophysics Data System (ADS)

    Bikiaris, D.; Daniilia, Sister; Sotiropoulou, S.; Katsimbiri, O.; Pavlidou, E.; Moutsatsou, A. P.; Chryssoulakis, Y.

    2000-01-01

    The most widely-used inorganic pigments of Byzantine and post-Byzantine hagiography are earth pigments called ochres such as, red and yellow ochres, limonite, goethite, raw and burnt sienna, caput mortuum and hematite. The present experimental work proposes a technique of differentiation that allows one to distinguish among all the different kinds of iron oxides, thereby providing a better understanding of the painting technique used on portable icons and wall paintings. The ratios between the main spectroscopic peaks, attributable to the major components usually present in ochres, were calculated and compared, one against the another, from the spectra obtained through micro-Raman spectroscopy. Elementary composition is also revealed through a scanning electron microscopy (SEM) analysis. The possibility for detailed study on a particular Byzantine ochre palette can thus be performed based on the small differences in its nature and composition. These differences can first be observed and then measured among all of the natural earth pigments, through μRaman and μFTIR spectroscopies.

  12. Effects of serum albumin on the degradation and cytotoxicity of single-walled carbon nanotubes.

    PubMed

    Ding, Yun; Tian, Rong; Yang, Zhen; Chen, Jianfa; Lu, Naihao

    2017-03-01

    Neutrophil myeloperoxidase (MPO) and peroxynitrite (ONOO(-)) can oxidatively biodegrade carboxylated single-walled carbon nanotubes (SWCNTs). The protein-SWCNTs interactions will play an important role in the degradation and cytotoxicity of nanotubes. Here, we investigated the binding of bovine serum albumin (BSA, a common and well-characterized model blood serum protein) to SWCNTs, and found that the hydrophobic and electrostatic interactions might be crucial factors in stabilizing the binding of SWCNTs with BSA. The binding of BSA could impair SWCNTs biodegradation in vitro through the competitive adsorption to nanotube. Both SWCNTs and BSA-SWCNTs were significantly degraded in zymosan-stimulated macrophages, and the degradation degree was more for BSA-SWCNTs. The mechanism for SWCNTs degradation in activated macrophages was further investigated to demonstrate the dominant participation of MPO and ONOO(-)-driven pathways. Moreover, binding of BSA to SWCNTs reduced cytotoxicity and degraded nanotubes induced less cytotoxicity than non-degraded nanotubes. The binding of BSA may be an important determinant for the biodegradation and cytotoxicity of SWCNTs in inflammatory cells, and therefore, provide a new route to mitigate the potential toxicity of nanotubes in future biomedical applications.

  13. Formation of indoor nitrous acid (HONO) by light-induced NO2 heterogeneous reactions with white wall paint.

    PubMed

    Bartolomei, Vincent; Sörgel, Matthias; Gligorovski, Sasho; Alvarez, Elena Gómez; Gandolfo, Adrien; Strekowski, Rafal; Quivet, Etienne; Held, Andreas; Zetzsch, Cornelius; Wortham, Henri

    2014-01-01

    Gaseous nitrogen dioxide (NO2) represents an oxidant that is present in relatively high concentrations in various indoor settings. Remarkably increased NO2 levels up to 1.5 ppm are associated with homes using gas stoves. The heterogeneous reactions of NO2 with adsorbed water on surfaces lead to the generation of nitrous acid (HONO). Here, we present a HONO source induced by heterogeneous reactions of NO2 with selected indoor paint surfaces in the presence of light (300 nm<λ<400 nm). We demonstrate that the formation of HONO is much more pronounced at elevated relative humidity. In the presence of light (5.5 W m(-2)), an increase of HONO production rate of up to 8.6·10(9) molecules cm(-2) s(-1) was observed at [NO2]=60 ppb and 50% relative humidity (RH). At higher light intensity of 10.6 (W m(-2)), the HONO production rate increased to 2.1·10(10) molecules cm(-2) s(-1). A high NO2 to HONO conversion yield of up to 84% was observed. This result strongly suggests that a light-driven process of indoor HONO production is operational. This work highlights the potential of paint surfaces to generate HONO within indoor environments by light-induced NO2 heterogeneous reactions.

  14. Microscopy and Microanalysis of an Extreme Case of Salt and Biodegradation in 17th Century Wall Paintings.

    PubMed

    Gil, Milene; Martins, Maria Rosário; Carvalho, Maria Luisa; Souto, Cátia; Longelin, Stephane; Cardoso, Ana; Mirão, José; Candeias, António Estevão

    2015-06-01

    The present study characterizes the main deterioration mechanisms affecting the early 17th frescoes of Casa de Fresco, the only known example in Portugal of a semi-underground leisure room richly decorated with a balcony over a water well. Frescoes from the vault are at risk due to salt weathering and biodeterioration. The aim of the research was identification of the deterioration materials, determination of their origin, and their effect on the frescoes before future intervention. Scanning electron microscopy with an energy-dispersive X-ray detector (SEM-EDS) was used to determine salt morphology and microanalysis. The mineralogical characterization was performed by X-ray powder diffraction, complemented with µ-Raman and µ-Fourier transform infrared spectroscopy. Biological assessment was evaluated with optical microscopy and SEM-EDS. Bacterial and fungal isolation and identification were performed using standard culture media and methods according to Bergey's Manual of Systematic Bacteriology and from the Compendium of Soil Fungi. The results show that Ca and Ca-Mg carbonates from the paint renderings are the predominant salt species affecting the site. Bacterial strains from the genera Bacillus and Pseudomonas and fungal strains from the Cladosporium spp. and Penicillium spp. were isolated in the salt formations, within and between the mortar layers. Azurite, malachite, and smalt paint layers are the most affected by the weathering conditions.

  15. Recognition and degradation of plant cell wall polysaccharides by two human gut symbionts.

    PubMed

    Martens, Eric C; Lowe, Elisabeth C; Chiang, Herbert; Pudlo, Nicholas A; Wu, Meng; McNulty, Nathan P; Abbott, D Wade; Henrissat, Bernard; Gilbert, Harry J; Bolam, David N; Gordon, Jeffrey I

    2011-12-01

    Symbiotic bacteria inhabiting the human gut have evolved under intense pressure to utilize complex carbohydrates, primarily plant cell wall glycans in our diets. These polysaccharides are not digested by human enzymes, but are processed to absorbable short chain fatty acids by gut bacteria. The Bacteroidetes, one of two dominant bacterial phyla in the adult gut, possess broad glycan-degrading abilities. These species use a series of membrane protein complexes, termed Sus-like systems, for catabolism of many complex carbohydrates. However, the role of these systems in degrading the chemically diverse repertoire of plant cell wall glycans remains unknown. Here we show that two closely related human gut Bacteroides, B. thetaiotaomicron and B. ovatus, are capable of utilizing nearly all of the major plant and host glycans, including rhamnogalacturonan II, a highly complex polymer thought to be recalcitrant to microbial degradation. Transcriptional profiling and gene inactivation experiments revealed the identity and specificity of the polysaccharide utilization loci (PULs) that encode individual Sus-like systems that target various plant polysaccharides. Comparative genomic analysis indicated that B. ovatus possesses several unique PULs that enable degradation of hemicellulosic polysaccharides, a phenotype absent from B. thetaiotaomicron. In contrast, the B. thetaiotaomicron genome has been shaped by increased numbers of PULs involved in metabolism of host mucin O-glycans, a phenotype that is undetectable in B. ovatus. Binding studies of the purified sensor domains of PUL-associated hybrid two-component systems in conjunction with transcriptional analyses demonstrate that complex oligosaccharides provide the regulatory cues that induce PUL activation and that each PUL is highly specific for a defined cell wall polymer. These results provide a view of how these species have diverged into different carbohydrate niches by evolving genes that target unique suites of

  16. Arsenal of plant cell wall degrading enzymes reflects host preference among plant pathogenic fungi.

    PubMed

    King, Brian C; Waxman, Katrina D; Nenni, Nicholas V; Walker, Larry P; Bergstrom, Gary C; Gibson, Donna M

    2011-02-16

    The discovery and development of novel plant cell wall degrading enzymes is a key step towards more efficient depolymerization of polysaccharides to fermentable sugars for the production of liquid transportation biofuels and other bioproducts. The industrial fungus Trichoderma reesei is known to be highly cellulolytic and is a major industrial microbial source for commercial cellulases, xylanases and other cell wall degrading enzymes. However, enzyme-prospecting research continues to identify opportunities to enhance the activity of T. reesei enzyme preparations by supplementing with enzymatic diversity from other microbes. The goal of this study was to evaluate the enzymatic potential of a broad range of plant pathogenic and non-pathogenic fungi for their ability to degrade plant biomass and isolated polysaccharides. Large-scale screening identified a range of hydrolytic activities among 348 unique isolates representing 156 species of plant pathogenic and non-pathogenic fungi. Hierarchical clustering was used to identify groups of species with similar hydrolytic profiles. Among moderately and highly active species, plant pathogenic species were found to be more active than non-pathogens on six of eight substrates tested, with no significant difference seen on the other two substrates. Among the pathogenic fungi, greater hydrolysis was seen when they were tested on biomass and hemicellulose derived from their host plants (commelinoid monocot or dicot). Although T. reesei has a hydrolytic profile that is highly active on cellulose and pretreated biomass, it was less active than some natural isolates of fungi when tested on xylans and untreated biomass. Several highly active isolates of plant pathogenic fungi were identified, particularly when tested on xylans and untreated biomass. There were statistically significant preferences for biomass type reflecting the monocot or dicot host preference of the pathogen tested. These highly active fungi are promising targets

  17. Effect of venous wall immobilization on the thermal degradation of collagen

    NASA Astrophysics Data System (ADS)

    Ignat'eva, N. Yu.; Zakharkina, O. L.; Lunin, V. V.; Sergeeva, E. A.; Mazaishvili, K. V.; Maksimov, S. V.

    2013-11-01

    The results from a comparative study of the thermal denaturation of collagen in the venous walls of reference samples and samples with varicose disease are presented. Changes in the organization of collagen network of the tissue matrix are detected via thermal analysis and multiphoton microscopy with recording of the second harmonic generation (SHG). It is established that the collagen network of venous walls degrades in varicose disease. It is shown that the disordering of the tertiary structure of collagen molecules is reflected in a 40% drop in the enthalpy of protein denaturation compared to reference (Δ H D = 12.4 ± 4.9 J/g dry residue). The disorganization of fiber structures is recorded on SHG images. It is shown that upon the hydrothermal heating of sequestered samples of venous walls, the complete degradation of the tissue network occurs at 75°C. However, it is noted that upon the mechanical immobilization of samples of both types, the stability of collagen increases and complete denaturation is observed at temperatures above 84°C. It is suggested that the number of available conformations of polypeptide chains in the random coil state falls under tension, lowering Δ S D and raising the temperature of the denaturation of protein.

  18. Degradation of lignified secondary cell walls of lucerne (Medicago sativa L.) by rumen fungi growing in methanogenic co-culture.

    PubMed

    Bootten, T J; Joblin, K N; McArdle, B H; Harris, P J

    2011-11-01

    To compare the abilities of the monocentric rumen fungi Neocallimastix frontalis, Piromyces communis and Caecomyces communis, growing in coculture with Methanobrevibacter smithii, to colonize and degrade lignified secondary cell walls of lucerne (alfalfa) hay. The cell walls of xylem cylinders isolated from stems of lucerne contained mostly xylans, cellulose and lignin together with a small proportion of pectic polysaccharides. All of these major components were removed during incubation with the three fungi, and differing cell wall polysaccharides were degraded to different extents. The greatest dry weight loss was found with N. frontalis and least with C. communis, and scanning electron microscopy revealed that these extensively colonized different cell types. C. communis specifically colonized secondary xylem fibres and showed much less degradation than N. frontalis and P. communis. Neocallimastix frontalis and P. communis were efficient degraders of the cell walls of lucerne xylem cylinders. Degradation occurred of pectic polysaccharides, xylan and cellulose. Loss of lignin from the xylem cylinders probably resulted from the cleavage of xylan releasing xylan-lignin complexes. Unlike rumen bacteria, the rumen fungi N. frontalis, P. communis and C. communis are able to degrade lignified secondary walls in lucerne stems. These fungi could improve forage utilization by ruminants and may have potential in the degradation of lignocellulosic biomass in the production of biofuels. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  19. Optical coherence tomography assessment of vessel wall degradation in aneurysmatic thoracic aortas

    NASA Astrophysics Data System (ADS)

    Real, Eusebio; Eguizabal, Alma; Pontón, Alejandro; Val-Bernal, J. Fernando; Mayorga, Marta; Revuelta, José M.; López-Higuera, José; Conde, Olga M.

    2013-06-01

    Optical coherence tomographic images of ascending thoracic human aortas from aneurysms exhibit disorders on the smooth muscle cell structure of the media layer of the aortic vessel as well as elastin degradation. Ex-vivo measurements of human samples provide results that correlate with pathologist diagnosis in aneurysmatic and control aortas. The observed disorders are studied as possible hallmarks for aneurysm diagnosis. To this end, the backscattering profile along the vessel thickness has been evaluated by fitting its decay against two different models, a third order polynomial fitting and an exponential fitting. The discontinuities present on the vessel wall on aneurysmatic aortas are slightly better identified with the exponential approach. Aneurysmatic aortic walls present uneven reflectivity decay when compared with healthy vessels. The fitting error has revealed as the most favorable indicator for aneurysm diagnosis as it provides a measure of how uniform is the decay along the vessel thickness.

  20. Stereo Painting Display Devices

    NASA Astrophysics Data System (ADS)

    Shafer, David

    1982-06-01

    The Spanish Surrealist artist Salvador Dali has recently perfected the art of producing two paintings which are stereo pairs. Each painting is separately quite remarkable, presenting a subject with the vivid realism and clarity for which Dali is famous. Due to the surrealistic themes of Dali's art, however, the subjects preser.ted with such naturalism only exist in his imagination. Despite this considerable obstacle to producing stereo art, Dali has managed to paint stereo pairs that display subtle differences of coloring and lighting, in addition to the essential perspective differences. These stereo paintings require a display method that will allow the viewer to experience stereo fusion, but which will not degrade the high quality of the art work. This paper gives a review of several display methods that seem promising in terms of economy, size, adjustability, and image quality.

  1. In situ X-ray fluorescence-based method to differentiate among red ochre pigments and yellow ochre pigments thermally transformed to red pigments of wall paintings from Pompeii.

    PubMed

    Marcaida, Iker; Maguregui, Maite; Fdez-Ortiz de Vallejuelo, Silvia; Morillas, Héctor; Prieto-Taboada, Nagore; Veneranda, Marco; Castro, Kepa; Madariaga, Juan Manuel

    2017-06-01

    Most of the magnificent wall paintings from the ancient city of Pompeii are decorated with red and yellow colors coming from the ochre pigments used. The thermal impact of the pyroclastic flow from the eruption of Vesuvius, in AD 79, promoted the transformation of some yellow painted areas to red. In this work, original red ochre, original yellow ochre, and transformed yellow ochre (nowadays showing a red color) of wall paintings from Pompeian houses (House of Marcus Lucretius and House of Gilded Cupids) were analyzed by means of a handheld energy-dispersive X-ray fluorescence spectrometer to develop a fast method that allows chemical differentiation of the original red ochre and the transformed yellow ochre. Principal component analysis of the multivariate obtained data showed that arsenic is the tracer element to distinguish between both red colored ochres. Moreover, Pompeian raw red and yellow ochre pigments recovered from the burial were analyzed in the laboratory with use of a benchtop energy-dispersive X-ray fluorescence spectrometer to confirm the elemental composition and the conclusions drawn from the in situ analysis according to the yellow ochre pigment transformation in real Pompeian wall paintings.

  2. Systems analysis of plant cell wall degradation by the model filamentous fungus Neurospora crassa

    PubMed Central

    Tian, Chaoguang; Beeson, William T.; Iavarone, Anthony T.; Sun, Jianping; Marletta, Michael A.; Cate, Jamie H. D.; Glass, N. Louise

    2009-01-01

    The filamentous fungus Neurospora crassa is a model laboratory organism, but in nature is commonly found growing on dead plant material, particularly grasses. Using functional genomics resources available for N. crassa, which include a near-full genome deletion strain set and whole genome microarrays, we undertook a system-wide analysis of plant cell wall and cellulose degradation. We identified approximately 770 genes that showed expression differences when N. crassa was cultured on ground Miscanthus stems as a sole carbon source. An overlap set of 114 genes was identified from expression analysis of N. crassa grown on pure cellulose. Functional annotation of up-regulated genes showed enrichment for proteins predicted to be involved in plant cell wall degradation, but also many genes encoding proteins of unknown function. As a complement to expression data, the secretome associated with N. crassa growth on Miscanthus and cellulose was determined using a shotgun proteomics approach. Over 50 proteins were identified, including 10 of the 23 predicted N. crassa cellulases. Strains containing deletions in genes encoding 16 proteins detected in both the microarray and mass spectrometry experiments were analyzed for phenotypic changes during growth on crystalline cellulose and for cellulase activity. While growth of some of the deletion strains on cellulose was severely diminished, other deletion strains produced higher levels of extracellular proteins that showed increased cellulase activity. These results show that the powerful tools available in N. crassa allow for a comprehensive system level understanding of plant cell wall degradation mechanisms used by a ubiquitous filamentous fungus. PMID:20018766

  3. Comparison of corn stover cell wall polysaccharide degradability by rumen microbes and a cellulosic ethanol conversion process

    USDA-ARS?s Scientific Manuscript database

    Release of fermentable cell wall sugars in the cellulosic ethanol conversion process is assumed similar to rumen degradability; however, available literature has only reported surrogate rumen degradation measures (dry matter, neutral detergent fiber, and fermentation gases). We determined 72-h in vi...

  4. Putative Seedling Ferulate Ester (sfe) Maize Mutant: Morphology, Biomass Yield, and Stover Cell Wall Composition and Rumen Degradability

    USDA-ARS?s Scientific Manuscript database

    Ferulate cross linking of lignin to arabinoxylan contributes to poor cell wall degradability of grass forages. We hypothesized that reduced ferulate ester deposition will result in formation of fewer ferulate ether cross links and improved degradability. Objectives were to determine if the putative ...

  5. Paint-Overspray Catcher

    NASA Technical Reports Server (NTRS)

    Weinstein, Leonard M.

    2003-01-01

    An apparatus to catch paint overspray has been proposed. Overspray is an unavoidable parasitic component of spray that occurs because the flow of air or other gas in the spray must turn at the sprayed surface. Very small droplets are carried away in this turning flow, and some land on adjacent surfaces not meant to be painted. The basic principle of the paint-spray catcher is to divert the overspray into a suction system at the boundary of the area to be painted. The paint-spray catcher (see figure) would include a toroidal plenum connected through narrow throat to a nozzle that would face toward the center of the torus, which would be positioned over the center of the area to be spray-painted. The plenum would be supported by four tubes that would also serve as suction exhaust ducts. The downstream ends of the tubes (not shown in the figure) would be connected to a filter on a suction pump. The pump would be rated to provide a suction mass flow somewhat greater than that of the directed spray gas stream, so that the nozzle would take in a small excess of surrounding gas and catch nearly all of the overspray. A small raised lip at the bottom edge of the nozzle would catch paint that landed inside the nozzle. Even if the paint is directly piston pumped, the droplets entrain an air flow by time they approach the wall, so there is always a gas stream to carry the excess droplets to the side. For long-duration spraying operations, it could be desirable to include a suction-drain apparatus to prevent overflowing and dripping of paint from inside the lip. A version without an external contraction and with the throat angled downward would be a more compact version of catcher, although it might be slightly less efficient.

  6. Paint Analysis

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Lewis Research Center (LEW) has assisted The Cleveland Museum of Art (CMA) in analyzing the museum's paintings. Because of the many layers of paint that are often involved, this is a complex process. The cross-section of a paint chip must be scanned with a microscope to determine whether a paint layer is original or a restoration. The paint samples, however, are rarely flat enough for high magnification viewing and are frequently scratched. LEW devised an automated method that produces intact, flat, polished paint cross-sections. A sophisticated microprocessor-controlled grinding and polishing machine was manually employed in preparation of exotic samples for aerospace research was a readily adaptable technique. It produced perfectly flat samples with clearly defined layers. The process has been used successfully on a number of paintings, and LEW and CMA are considering additional applications.

  7. Paint it nanoblack

    NASA Astrophysics Data System (ADS)

    Perkowitz, Sidney

    2016-08-01

    Ever since our ancestors painted images on the walls of caves, artists have sought pigments to represent the 10 million tints that humans can differentiate. Now they have a new ally: researchers who are using optical design principles, nanotechnology and inspiration from nature to create deeper blacks and purer whites.

  8. Bacteriophage Tuc2009 Encodes a Tail-Associated Cell Wall-Degrading Activity

    PubMed Central

    Kenny, John G.; McGrath, Stephen; Fitzgerald, Gerald F.; van Sinderen, Douwe

    2004-01-01

    Tuc2009 is a P335-type member of the tailed-phage supergroup Siphoviridae and was originally identified as a resident prophage of the gram-positive bacterium Lactococcus lactis UC509. A Tuc2009 gene designated tal2009 which is located within the morphogenic module was shown to specify a lytic activity within the 3′ portion of its coding region. Comparative sequence analysis indicated that the cell wall-degrading part of Tal2009 is a member of the M37 protein family and that Tal2009 lacks a cell-binding domain, a finding supported by binding studies. Tal2009 appears to undergo self-mediated posttranslational processing in both L. lactis and Escherichia coli. Antibodies directed against a purified C-terminal portion of Tal2009 were used for immunoelectron microscopy, which showed that Tal2009 is located at the tail tip of Tuc2009. Antibody neutralization studies demonstrated that Tal2009-directed antibodies inhibited the ability of phage to mediate host lysis by more than 100-fold. These data indicate that tal2009 encodes a tail-associated lysin involved in localized cell wall degradation, thus allowing the Tuc2009 DNA injection machinery access to the membrane of its bacterial host. PMID:15150235

  9. Deposition of lithium on a plasma edge probe in TFTR -- Behavior of lithium-painted walls interacting with edge plasmas

    SciTech Connect

    Hirooka, Y.; Ashida, K.; Kugel, H.

    1998-05-01

    Recent observations have indicated that lithium pellet injection wall conditioning plays an important role in achieving the enhanced supershot regime in TFTR. However, little is understood about the behavior of lithium-coated limiter walls, interacting with edge plasmas. In the final campaign of TFTR, a cylindrical carbon fiber composite probe was inserted into the boundary plasma region and exposed to ohmically-heated deuterium discharges with lithium pellet injection. The ion-drift side probe surface exhibits a sign of codeposition of lithium, carbon, oxygen, and deuterium, whereas the electron side essentially indicates high-temperature erosion. It is found that lithium is incorporated in these codeposits in the form of oxide at the concentration of a few percent. In the electron side, lithium has been found to penetrate deeply into the probe material, presumably via rapid diffusion through interplane spaces in the graphite crystalline. Though it is not conclusive, materials mixing in the carbon and lithium system appears to be a key process in successful lithium wall conditioning.

  10. Characterization of Wall Teichoic Acid Degradation by the Bacteriophage ϕ29 Appendage Protein GP12 Using Synthetic Substrate Analogs*

    PubMed Central

    Myers, Cullen L.; Ireland, Ronald G.; Garrett, Teresa A.; Brown, Eric D.

    2015-01-01

    The genetics and enzymology of the biosynthesis of wall teichoic acid have been the extensively studied, however, comparatively little is known regarding the enzymatic degradation of this biological polymer. The GP12 protein from the Bacillus subtilis bacteriophage ϕ29 has been implicated as a wall teichoic acid hydrolase. We have studied the wall teichoic acid hydrolase activity of pure, recombinant GP12 using chemically defined wall teichoic acid analogs. The GP12 protein had potent wall teichoic acid hydrolytic activity in vitro and demonstrated ∼13-fold kinetic preference for glycosylated poly(glycerol phosphate) teichoic acid compared with non-glycosylated. Product distribution patterns suggested that the degradation of glycosylated polymers proceeded from the hydroxyl terminus of the polymer, whereas hydrolysis occurred at random sites in the non-glycosylated polymer. In addition, we present evidence that the GP12 protein possesses both phosphodiesterase and phosphomonoesterase activities. PMID:26085106

  11. Characterization of Wall Teichoic Acid Degradation by the Bacteriophage ϕ29 Appendage Protein GP12 Using Synthetic Substrate Analogs.

    PubMed

    Myers, Cullen L; Ireland, Ronald G; Garrett, Teresa A; Brown, Eric D

    2015-07-31

    The genetics and enzymology of the biosynthesis of wall teichoic acid have been the extensively studied, however, comparatively little is known regarding the enzymatic degradation of this biological polymer. The GP12 protein from the Bacillus subtilis bacteriophage ϕ29 has been implicated as a wall teichoic acid hydrolase. We have studied the wall teichoic acid hydrolase activity of pure, recombinant GP12 using chemically defined wall teichoic acid analogs. The GP12 protein had potent wall teichoic acid hydrolytic activity in vitro and demonstrated ∼13-fold kinetic preference for glycosylated poly(glycerol phosphate) teichoic acid compared with non-glycosylated. Product distribution patterns suggested that the degradation of glycosylated polymers proceeded from the hydroxyl terminus of the polymer, whereas hydrolysis occurred at random sites in the non-glycosylated polymer. In addition, we present evidence that the GP12 protein possesses both phosphodiesterase and phosphomonoesterase activities.

  12. Comparative analysis of fungal genomes reveals different plant cell wall degrading capacity in fungi

    PubMed Central

    2013-01-01

    Background Fungi produce a variety of carbohydrate activity enzymes (CAZymes) for the degradation of plant polysaccharide materials to facilitate infection and/or gain nutrition. Identifying and comparing CAZymes from fungi with different nutritional modes or infection mechanisms may provide information for better understanding of their life styles and infection models. To date, over hundreds of fungal genomes are publicly available. However, a systematic comparative analysis of fungal CAZymes across the entire fungal kingdom has not been reported. Results In this study, we systemically identified glycoside hydrolases (GHs), polysaccharide lyases (PLs), carbohydrate esterases (CEs), and glycosyltransferases (GTs) as well as carbohydrate-binding modules (CBMs) in the predicted proteomes of 103 representative fungi from Ascomycota, Basidiomycota, Chytridiomycota, and Zygomycota. Comparative analysis of these CAZymes that play major roles in plant polysaccharide degradation revealed that fungi exhibit tremendous diversity in the number and variety of CAZymes. Among them, some families of GHs and CEs are the most prevalent CAZymes that are distributed in all of the fungi analyzed. Importantly, cellulases of some GH families are present in fungi that are not known to have cellulose-degrading ability. In addition, our results also showed that in general, plant pathogenic fungi have the highest number of CAZymes. Biotrophic fungi tend to have fewer CAZymes than necrotrophic and hemibiotrophic fungi. Pathogens of dicots often contain more pectinases than fungi infecting monocots. Interestingly, besides yeasts, many saprophytic fungi that are highly active in degrading plant biomass contain fewer CAZymes than plant pathogenic fungi. Furthermore, analysis of the gene expression profile of the wheat scab fungus Fusarium graminearum revealed that most of the CAZyme genes related to cell wall degradation were up-regulated during plant infection. Phylogenetic analysis also

  13. Comparative analysis of fungal genomes reveals different plant cell wall degrading capacity in fungi.

    PubMed

    Zhao, Zhongtao; Liu, Huiquan; Wang, Chenfang; Xu, Jin-Rong

    2013-04-23

    Fungi produce a variety of carbohydrate activity enzymes (CAZymes) for the degradation of plant polysaccharide materials to facilitate infection and/or gain nutrition. Identifying and comparing CAZymes from fungi with different nutritional modes or infection mechanisms may provide information for better understanding of their life styles and infection models. To date, over hundreds of fungal genomes are publicly available. However, a systematic comparative analysis of fungal CAZymes across the entire fungal kingdom has not been reported. In this study, we systemically identified glycoside hydrolases (GHs), polysaccharide lyases (PLs), carbohydrate esterases (CEs), and glycosyltransferases (GTs) as well as carbohydrate-binding modules (CBMs) in the predicted proteomes of 103 representative fungi from Ascomycota, Basidiomycota, Chytridiomycota, and Zygomycota. Comparative analysis of these CAZymes that play major roles in plant polysaccharide degradation revealed that fungi exhibit tremendous diversity in the number and variety of CAZymes. Among them, some families of GHs and CEs are the most prevalent CAZymes that are distributed in all of the fungi analyzed. Importantly, cellulases of some GH families are present in fungi that are not known to have cellulose-degrading ability. In addition, our results also showed that in general, plant pathogenic fungi have the highest number of CAZymes. Biotrophic fungi tend to have fewer CAZymes than necrotrophic and hemibiotrophic fungi. Pathogens of dicots often contain more pectinases than fungi infecting monocots. Interestingly, besides yeasts, many saprophytic fungi that are highly active in degrading plant biomass contain fewer CAZymes than plant pathogenic fungi. Furthermore, analysis of the gene expression profile of the wheat scab fungus Fusarium graminearum revealed that most of the CAZyme genes related to cell wall degradation were up-regulated during plant infection. Phylogenetic analysis also revealed a complex

  14. Improved thermal paint formulation

    NASA Technical Reports Server (NTRS)

    Gates, D. W.; Roger, F. O.; Zerlaut, G. A.

    1971-01-01

    Potassium silicate-treated zinc oxide paint stabilizes pigment against ultraviolet-induced, bleachable degradation in infrared region, and permits use of ZnO as pigment in ultraviolet-stable coatings based upon polymethyl siloxane elastomers and resins. Material has low absorptance/emittance ratio.

  15. Use of in situ and confocal Raman spectroscopy to study the nature and distribution of carotenoids in brown patinas from a deteriorated wall painting in Marcus Lucretius House (Pompeii).

    PubMed

    Maguregui, M; Knuutinen, U; Trebolazabala, J; Morillas, H; Castro, K; Martinez-Arkarazo, I; Madariaga, J M

    2012-02-01

    Colonisation of wall paintings by microorganisms and other organisms is a well-known problematic phenomenon. Besides taxonomic identification of the biodeteriogen, it is essential to evaluate the consequences of the colonisation, e.g., unsightly coloured patinas. This work proposes new methodology for characterisation of the nature of the main carotenoids and their distribution in brown stains or patinas of a deteriorated wall painting on the north wall of the atrium of Marcus Lucretius House (Pompeii, Italy). Characterisation of the brown patinas and surrounding areas (plaster and polychromy) from the wall painting started with in situ screening using, mainly, a portable Raman instrument with a handheld FTIR (DRIFTS sampling interface) in order to select the sampling areas suitable for further analysis in the laboratory. Two wall painting fragments were then analysed in the laboratory in two steps. First, microscopic observations (SEM and phase-contrast microscopy) were used to determine whether biodeteriogens were present in the samples. In a second step, confocal Raman microscopy (785 and 514 nm excitation lasers) was used to characterise the main biogenic compounds of the brown stains. Because of the resonance Raman effect (514 nm excitation laser), it was possible to obtain reliable Raman features to assign not only the nature of the main biogenic pigments (carotenoids) present in the stains, but also their spatial conformation. Moreover, Raman confocal applications, for example, Raman imaging and depth profiling were also used in a first attempt to determine the distribution of biosynthesised carotenoids in the stains, and to determine the thickness of the brown patinas.

  16. Diversity of Beetle Genes Encoding Novel Plant Cell Wall Degrading Enzymes

    PubMed Central

    Pauchet, Yannick; Wilkinson, Paul; Chauhan, Ritika; ffrench-Constant, Richard H.

    2010-01-01

    Plant cell walls are a heterogeneous mixture of polysaccharides and proteins that require a range of different enzymes to degrade them. Plant cell walls are also the primary source of cellulose, the most abundant and useful biopolymer on the planet. Plant cell wall degrading enzymes (PCWDEs) are therefore important in a wide range of biotechnological processes from the production of biofuels and food to waste processing. However, despite the fact that the last common ancestor of all deuterostomes was inferred to be able to digest, or even synthesize, cellulose using endogenous genes, all model insects whose complete genomes have been sequenced lack genes encoding such enzymes. To establish if the apparent “disappearance” of PCWDEs from insects is simply a sampling problem, we used 454 mediated pyrosequencing to scan the gut transcriptomes of beetles that feed on a variety of plant derived diets. By sequencing the transcriptome of five beetles, and surveying publicly available ESTs, we describe 167 new beetle PCWDEs belonging to eight different enzyme families. This survey proves that these enzymes are not only present in non-model insects but that the multigene families that encode them are apparently undergoing complex birth-death dynamics. This reinforces the observation that insects themselves, and not just their microbial symbionts, are a rich source of PCWDEs. Further it emphasises that the apparent absence of genes encoding PCWDEs from model organisms is indeed simply a sampling artefact. Given the huge diversity of beetles alive today, and the diversity of their lifestyles and diets, we predict that beetle guts will emerge as an important new source of enzymes for use in biotechnology. PMID:21179425

  17. Degradation of starchy endosperm cell walls in nongerminating sterilized barley by fungi.

    PubMed

    Noots, I; Derycke, V; Cornelis, K; Michiels, C; Delcour, J A; Delrue, R; De Keersmaeker, J; Coppens, T

    2001-02-01

    Strains of fungi from different origins, including isolates of the natural microflora of barley, were screened for their ability to modify barley starchy endosperm cell walls in situ. In an initial step, fungi were selected that degrade the major component of the cell walls, that is, (1-->3),(1-->4)-beta-D-glucan, in vitro on artificial media. Nongerminating, sterilized barley, obtained by gamma-irradiation, was inoculated with such fungi and subjected to solid state fermentation under conditions resembling those of a traditional malting process. For some strains of fungi, a clear correlation between the production of endo-beta-glucanase and the friability of the treated kernels was found. Image analysis of Calcofluor stained longitudinal sections of barley kernels fermented with the endo-beta-glucanase producing strains showed that starchy endosperm cell walls were modified. As malt quality is inversely related to its (1-->3),(1-->4)-beta-D-glucan content, the selected strains have high potential to be used as starter cultures during malt production, contributing to the processing quality of the final product.

  18. Ofloxacin-like antibiotics inhibit pneumococcal cell wall-degrading virulence factors.

    PubMed

    Fernández-Tornero, Carlos; García, Ernesto; de Pascual-Teresa, Beatriz; López, Rubens; Giménez-Gallego, Guillermo; Romero, Antonio

    2005-05-20

    The search for new drugs against Streptococcus pneumoniae (pneumococcus) is driven by the 1.5 million deaths it causes annually. Choline-binding proteins attach to the pneumococcal cell wall through domains that recognize choline moieties, and their involvement in pneumococcal virulence makes them potential targets for drug development. We have defined chemical criteria involved in the docking of small molecules from a three-dimensional structural library to the major pneumococcal autolysin (LytA) choline binding domain. These criteria were used to identify compounds that could interfere with the attachment of this protein to the cell wall, and several quinolones that fit this framework were found to inhibit the cell wall-degrading activity of LytA. Furthermore, these compounds produced similar effects on other enzymes with different catalytic activities but that contained a similar choline binding domain; that is, autolysin (LytC) and the phage lytic enzyme (Cpl-1). Finally, we resolved the crystal structure of the complex between the choline binding domain of LytA and ofloxacin at a resolution of 2.6 Angstroms. These data constitute an important launch pad from which effective drugs to combat pneumococcal infections can be developed.

  19. SEM backscattered-electron images of paint cross sections as information source for the presence of the lead white pigment and lead-related degradation and migration phenomena in oil paintings.

    PubMed

    Keune, Katrien; van Loon, Annelies; Boon, Jaap J

    2011-10-01

    Scanning electron microscopy backscattered-electron images of paint cross sections show the compositional contrast within the paint system. They not only give valuable information about the pigment composition and layer structure but also about the aging processes in the paint. This article focuses on the reading of backscatter images of lead white-containing samples from traditional oil paintings (17th-19th centuries). In contrast to modern lead white, traditional stack process lead white is characterized by a wide particle size distribution. Changes in particle morphology and distribution are indications of chemical/physical reactivity in the paint. Lead white can be affected by free fatty acids to form lead soaps. The dissolution of lead white can be recognized in the backscatter image by gray (less scattering) peripheries around particles and gray amorphous areas as opposed to the well-defined, highly scattering intact lead white particles. The small particles react away first, while the larger particles/lumps can still be visible. Formed lead soaps appear to migrate or diffuse through the semipermeable paint system. Lead-rich bands around particles, at layer interfaces and in the paint medium, are indications of transport. The presence of lead-containing crystals at the paint surface or inside aggregates furthermore point to the migration and mineralization of lead soaps.

  20. Comparative secretome analysis suggests low plant cell wall degrading capacity in Frankia symbionts

    PubMed Central

    Mastronunzio, Juliana E; Tisa, Louis S; Normand, Philippe; Benson, David R

    2008-01-01

    cell wall polysaccharide degradation may not be crucial to root infection, or that this degradation varies among strains. We hypothesize that the relative lack of secreted polysaccharide-degrading enzymes in Frankia reflects a strategy used by these bacteria to avoid eliciting host defense responses. The esterases, lipases, and proteases found in the core Frankia secretome might facilitate hyphal penetration through the cell wall, release carbon sources, or modify chemical signals. The core secretome also includes extracellular solute-binding proteins and Frankia-specific hypothetical proteins that may enable the actinorhizal symbiosis. PMID:18226217

  1. Divergent selection for ester-linked diferulates in maize pith stalk tissues. Effects on cell wall composition and degradability.

    PubMed

    Barros-Rios, Jaime; Malvar, Rosa A; Jung, Hans-Joachim G; Bunzel, Mirko; Santiago, Rogelio

    2012-11-01

    Cross-linking of grass cell wall components through diferulates (DFAs) has a marked impact on cell wall properties. However, results of genetic selection for DFA concentration have not been reported for any grass species. We report here the results of direct selection for ester-linked DFA concentration in maize stalk pith tissues and the associated changes in cell wall composition and biodegradability. After two cycles of divergent selection, maize populations selected for higher total DFA (DFAT) content (CHs) had 16% higher DFAT concentrations than populations selected for lower DFAT content (CLs). These significant DFA concentration gains suggest that DFA deposition in maize pith parenchyma cell walls is a highly heritable trait that is genetically regulated and can be modified trough conventional breeding. Maize populations selected for higher DFAT had 13% less glucose and 10% lower total cell wall concentration than CLs, suggesting that increased cross-linking of feruloylated arabinoxylans results in repacking of the matrix and possibly in thinner and firmer cell walls. Divergent selection affected esterified DFAT and monomeric ferulate ether cross link concentrations differently, supporting the hypothesis that the biosynthesis of these cell wall components are separately regulated. As expected, a more higher DFA ester cross-coupled arabinoxylan network had an effect on rumen cell wall degradability (CLs showed 12% higher 24-h total polysaccharide degradability than CHs). Interestingly, 8-8-coupled DFAs, previously associated with cell wall strength, were the best predictors of pith cell wall degradability (negative impact). Thus, further research on the involvement of these specific DFA regioisomers in limiting cell wall biodegradability is encouraged.

  2. Systems Identification and Characterization of Cell Wall Reassembly and Degradation Related Genes in Glycine max (L.) Merill, a Bioenergy Legume.

    PubMed

    Nawaz, Muhammad Amjad; Rehman, Hafiz Mamoon; Imtiaz, Muhammad; Baloch, Faheem Shehzad; Lee, Jeong Dong; Yang, Seung Hwan; Lee, Soo In; Chung, Gyuhwa

    2017-09-07

    Soybean is a promising biomass resource for generation of second-generation biofuels. Despite the utility of soybean cellulosic biomass and post-processing residues in biofuel generation, there is no comprehensive information available on cell wall loosening and degradation related gene families. In order to achieve enhanced lignocellulosic biomass with softened cell walls and reduced recalcitrance, it is important to identify genes involved in cell wall polymer loosening and degrading. Comprehensive genome-wide analysis of gene families involved in cell wall modifications is an efficient stratagem to find new candidate genes for soybean breeding for expanding biofuel industry. We report the identification of 505 genes distributed among 12 gene families related to cell wall loosening and degradation. 1262 tandem duplication events contributed towards expansion and diversification of studied gene families. We identified 687 Simple Sequence Repeat markers and 5 miRNA families distributed on 316 and 10 genes, respectively. Publically available microarray datasets were used to explore expression potential of identified genes in soybean plant developmental stages, 68 anatomical parts, abiotic and biotic stresses. Co-expression networks revealed transcriptional coordination of different gene families involved in cell wall loosening and degradation process.

  3. Metatranscriptomic Analyses of Plant Cell Wall Polysaccharide Degradation by Microorganisms in the Cow Rumen

    PubMed Central

    Dai, Xin; Tian, Yan; Li, Jinting; Su, Xiaoyun; Wang, Xuewei; Zhao, Shengguo; Liu, Li; Luo, Yingfeng; Liu, Di; Zheng, Huajun; Wang, Jiaqi; Dong, Zhiyang

    2014-01-01

    The bovine rumen represents a highly specialized bioreactor where plant cell wall polysaccharides (PCWPs) are efficiently deconstructed via numerous enzymes produced by resident microorganisms. Although a large number of fibrolytic genes from rumen microorganisms have been identified, it remains unclear how they are expressed in a coordinated manner to efficiently degrade PCWPs. In this study, we performed a metatranscriptomic analysis of the rumen microbiomes of adult Holstein cows fed a fiber diet and obtained a total of 1,107,083 high-quality non-rRNA reads with an average length of 483 nucleotides. Transcripts encoding glycoside hydrolases (GHs) and carbohydrate binding modules (CBMs) accounted for ∼1% and ∼0.1% of the total non-rRNAs, respectively. The majority (∼98%) of the putative cellulases belonged to four GH families (i.e., GH5, GH9, GH45, and GH48) and were primarily synthesized by Ruminococcus and Fibrobacter. Notably, transcripts for GH48 cellobiohydrolases were relatively abundant compared to the abundance of transcripts for other cellulases. Two-thirds of the putative hemicellulases were of the GH10, GH11, and GH26 types and were produced by members of the genera Ruminococcus, Prevotella, and Fibrobacter. Most (∼82%) predicted oligosaccharide-degrading enzymes were GH1, GH2, GH3, and GH43 proteins and were from a diverse group of microorganisms. Transcripts for CBM10 and dockerin, key components of the cellulosome, were also relatively abundant. Our results provide metatranscriptomic evidence in support of the notion that members of the genera Ruminococcus, Fibrobacter, and Prevotella are predominant PCWP degraders and point to the significant contribution of GH48 cellobiohydrolases and cellulosome-like structures to efficient PCWP degradation in the cow rumen. PMID:25501482

  4. Development and application of a suite of polysaccharide-degrading enzymes for analyzing plant cell walls

    PubMed Central

    Bauer, Stefan; Vasu, Prasanna; Persson, Staffan; Mort, Andrew J.; Somerville, Chris R.

    2006-01-01

    To facilitate analysis of plant cell wall polysaccharide structure and composition, we cloned 74 genes encoding polysaccharide-degrading enzymes from Aspergillus nidulans, Aspergillus fumigatus, and Neurospora crassa and expressed the genes as secreted proteins with C-terminal Myc and 6× His tags. Most of the recombinant enzymes were active in enzyme assays, and optima for pH and temperature were established. A subset of the enzymes was used to fragment polysaccharides from the irregular xylem 9 (irx9) mutant of Arabidopsis. The analysis revealed a decrease in the abundance of xylan in the mutant, indicating that the IRX9 gene, which encodes a putative family 43 glycosyltransferase, is required for xylan synthesis. PMID:16844780

  5. Development and application of a suite of polysaccharide-degrading enzymes for analyzing plant cell walls.

    PubMed

    Bauer, Stefan; Vasu, Prasanna; Persson, Staffan; Mort, Andrew J; Somerville, Chris R

    2006-07-25

    To facilitate analysis of plant cell wall polysaccharide structure and composition, we cloned 74 genes encoding polysaccharide-degrading enzymes from Aspergillus nidulans, Aspergillus fumigatus, and Neurospora crassa and expressed the genes as secreted proteins with C-terminal Myc and 6x His tags. Most of the recombinant enzymes were active in enzyme assays, and optima for pH and temperature were established. A subset of the enzymes was used to fragment polysaccharides from the irregular xylem 9 (irx9) mutant of Arabidopsis. The analysis revealed a decrease in the abundance of xylan in the mutant, indicating that the IRX9 gene, which encodes a putative family 43 glycosyltransferase, is required for xylan synthesis.

  6. Painted Pickup.

    ERIC Educational Resources Information Center

    Wheeler, Kimberly

    2001-01-01

    Discusses a six week art class project for elementary school children that lasted for six weeks. Explains that the students painted sunflowers in the style of Vincent van Gogh over the rust spots of a pickup truck. Reports that the painting served as great publicity for the art classes. (CMK)

  7. Painted Pickup.

    ERIC Educational Resources Information Center

    Wheeler, Kimberly

    2001-01-01

    Discusses a six week art class project for elementary school children that lasted for six weeks. Explains that the students painted sunflowers in the style of Vincent van Gogh over the rust spots of a pickup truck. Reports that the painting served as great publicity for the art classes. (CMK)

  8. Painted Rhythms.

    ERIC Educational Resources Information Center

    Bastian, Duane

    1985-01-01

    In this art activity gifted students, ages 10 to 13, learn about internal and external rhythms and make a painting of an internal rhythm. The lesson can be expanded with a discussion of Kandinsky, Pollock, and other painters who have painted sound or have demonstrated rhythms. (RM)

  9. Face Painting.

    ERIC Educational Resources Information Center

    Brooks, Diana

    1995-01-01

    Discusses the use of face painting as a technique for making the endangered species issue tangible for children while addressing the complexity of the issue. Children are "given" an animal of their own and are educated about the animal while having their faces painted to resemble the animal. (LZ)

  10. Monster Paintings

    ERIC Educational Resources Information Center

    Huggler, Silvia

    2010-01-01

    In this article, the author describes a unit on monsters wherein students were charged with painting an imaginary character and, in so doing, demonstrated mastery of expression, organization of space, control of paint media, and application of the elements of art. Students discovered how color and line could be used to convey expression. The media…

  11. Monster Paintings

    ERIC Educational Resources Information Center

    Huggler, Silvia

    2010-01-01

    In this article, the author describes a unit on monsters wherein students were charged with painting an imaginary character and, in so doing, demonstrated mastery of expression, organization of space, control of paint media, and application of the elements of art. Students discovered how color and line could be used to convey expression. The media…

  12. Heterologous Expression of Plant Cell Wall Degrading Enzymes for Effective Production of Cellulosic Biofuels

    PubMed Central

    Jung, Sang-Kyu; Parisutham, Vinuselvi; Jeong, Seong Hun; Lee, Sung Kuk

    2012-01-01

    A major technical challenge in the cost-effective production of cellulosic biofuel is the need to lower the cost of plant cell wall degrading enzymes (PCDE), which is required for the production of sugars from biomass. Several competitive, low-cost technologies have been developed to produce PCDE in different host organisms such as Escherichia coli, Zymomonas mobilis, and plant. Selection of an ideal host organism is very important, because each host organism has its own unique features. Synthetic biology-aided tools enable heterologous expression of PCDE in recombinant E. coli or Z. mobilis and allow successful consolidated bioprocessing (CBP) in these microorganisms. In-planta expression provides an opportunity to simplify the process of enzyme production and plant biomass processing and leads to self-deconstruction of plant cell walls. Although the future of currently available technologies is difficult to predict, a complete and viable platform will most likely be available through the integration of the existing approaches with the development of breakthrough technologies. PMID:22911272

  13. Chapter 3.03 - Multifunctional Enzyme Systems for Plant Cell Wall Degradation

    SciTech Connect

    Xu, Qi; Luo, Yonghua; Ding, Shi-You; Himmel, Michael E.; Bu, Lintao; Lamed, Raphael; Bayer, Edward A.

    2011-10-14

    Multifunctional enzymes refer to proteins that consist of two or more catalytic modules. Many microorganisms use multifunctional enzymes to efficiently break down the recalcitrant polymeric networks that constitute plant cell walls. Future applications of multifunctional enzymes may represent a potential solution to the problem of high enzyme cost for processing lignocellulosic biomass into fermentable sugars. Currently, commercial enzyme mixtures used in simultaneous saccharification fermentation process for biofuel production are derived primarily from free enzyme systems produced by fungi. In this context, we have analyzed the modular structures of 16 937 genes corresponding to 34 glycoside hydrolase families putatively related to the degradation of lignocellulose in the Carbohydrate Active enZyme (CAZy) database. Among these genes, 64 gene sequences have been identified to putatively encode multifunctional enzymes, and up to five catalytic modules have been found in a single polypeptide. Based on their deduced polypeptide sequences, they can be classified into four types, that is, cellulase-cellulase, cellulase-hemicellulase, hemicellulase-hemicellulase, and hemicellulase-carbohydrate esterase. The compositional modules and architectural structures of these enzymes are analyzed here, and their putative activities on breaking down cell walls are discussed. We further discuss the predicted intramolecular synergistic mechanisms between the catalytic modules, including substrate channeling, which is a mechanism often proposed for carbohydrate-binding modules residing in multifunctional enzymes. Furthermore, the potential applications of native and engineered multifunctional enzymes for biomass conversion technology are also reviewed.

  14. Correction: Comparative analysis of fungal genomes reveals different plant cell wall degrading capacity in fungi

    PubMed Central

    2014-01-01

    . Importantly, cellulases of some GH families are present in fungi that are not known to have cellulose-degrading ability. In addition, our results also showed that in general, plant pathogenic fungi have the highest number of CAZymes. Biotrophic fungi tend to have fewer CAZymes than necrotrophic and hemibiotrophic fungi. Pathogens of dicots often contain more pectinases than fungi infecting monocots. Interestingly, besides yeasts, many saprophytic fungi that are highly active in degrading plant biomass contain fewer CAZymes than plant pathogenic fungi. Furthermore, analysis of the gene expression profile of the wheat scab fungus Fusarium graminearum revealed that most of the CAZyme genes related to cell wall degradation were up-regulated during plant infection. Phylogenetic analysis also revealed a complex history of lineage-specific expansions and attritions for the PL1 family. Conclusions Our study provides insights into the variety and expansion of fungal CAZyme classes and revealed the relationship of CAZyme size and diversity with their nutritional strategy and host specificity. PMID:24422981

  15. Correction: Comparative analysis of fungal genomes reveals different plant cell wall degrading capacity in fungi.

    PubMed

    Zhao, Zhongtao; Liu, Huiquan; Wang, Chenfang; Xu, Jin-Rong

    2014-01-03

    families are present in fungi that are not known to have cellulose-degrading ability. In addition, our results also showed that in general, plant pathogenic fungi have the highest number of CAZymes. Biotrophic fungi tend to have fewer CAZymes than necrotrophic and hemibiotrophic fungi. Pathogens of dicots often contain more pectinases than fungi infecting monocots. Interestingly, besides yeasts, many saprophytic fungi that are highly active in degrading plant biomass contain fewer CAZymes than plant pathogenic fungi. Furthermore, analysis of the gene expression profile of the wheat scab fungus Fusarium graminearum revealed that most of the CAZyme genes related to cell wall degradation were up-regulated during plant infection. Phylogenetic analysis also revealed a complex history of lineage-specific expansions and attritions for the PL1 family. Our study provides insights into the variety and expansion of fungal CAZyme classes and revealed the relationship of CAZyme size and diversity with their nutritional strategy and host specificity.

  16. The sfe Maize Mutant: Reduced Ferulate Cross Linking Improves Rumen Cell Wall Degradability and Milk Production by Dairy Cows

    USDA-ARS?s Scientific Manuscript database

    A putative mutant has been identified in maize that reduces ferulate cross linking of lignin to arabinoxylan in mature stover, increases in vitro rumen cell wall degradability, and increases milk production by cows. The seedling ferulate ester (sfe) mutant was discovered in a Mu transposon-mutated p...

  17. Genomic characterization of plant cell wall degrading enzymes and in silico analysis of xylanses and polygalacturonases of Fusarium virguliforme

    USDA-ARS?s Scientific Manuscript database

    Plant cell wall degrading enzymes (PCWDEs) are important effectors for plant pathogens to invade plants. In this study, the composition of PCWDEs in Fusarium virguliforme that were grown for 5-days and 20 days in liquid medium was determined by RNA-Seq. Differential expression analysis showed more P...

  18. Space Paint

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Developed at Goddard, this improved inorganic paint may help protect coastal bridges subject to extreme corrosion from seawater spray. Potassium silicate formulated into a thin waterbase binder that sprays easily, adheres readily, and can be heavily loaded with zinc particles to provide uniform coverage in a single coat. Stanford Research Institute has measured an annual market in excess of $2 billion in painting highway bridges, utility pipelines, nuclear reactors, and railcar hoppers. Other suitable markets include offshore drilling facilities, railroad bridges, and ships.

  19. Differential expression of endogenous plant cell wall degrading enzyme genes in the stick insect (Phasmatodea) midgut.

    PubMed

    Shelomi, Matan; Jasper, W Cameron; Atallah, Joel; Kimsey, Lynn S; Johnson, Brian R

    2014-10-21

    Stick and leaf insects (Phasmatodea) are an exclusively leaf-feeding order of insects with no record of omnivory, unlike other "herbivorous" Polyneoptera. They represent an ideal system for investigating the adaptations necessary for obligate folivory, including plant cell wall degrading enzymes (PCWDEs). However, their physiology and internal anatomy is poorly understood, with limited genomic resources available. We de novo assembled transcriptomes for the anterior and posterior midguts of six diverse Phasmatodea species, with RNA-Seq on one exemplar species, Peruphasma schultei. The latter's assembly yielded >100,000 transcripts, with over 4000 transcripts uniquely or more highly expressed in specific midgut sections. Two to three dozen PCWDE encoding gene families, including cellulases and pectinases, were differentially expressed in the anterior midgut. These genes were also found in genomic DNA from phasmid brain tissue, suggesting endogenous production. Sequence alignments revealed catalytic sites on most PCWDE transcripts. While most phasmid PCWDE genes showed homology with those of other insects, the pectinases were homologous to bacterial genes. We identified a large and diverse PCWDE repertoire endogenous to the phasmids. If these expressed genes are translated into active enzymes, then phasmids can theoretically break plant cell walls into their monomer components independently of microbial symbionts. The differential gene expression between the two midgut sections provides the first molecular hints as to their function in living phasmids. Our work expands the resources available for industrial applications of animal-derived PCWDEs, and facilitates evolutionary analysis of lower Polyneopteran digestive enzymes, including the pectinases whose origin in Phasmatodea may have been a horizontal transfer event from bacteria.

  20. Coevolution and Life Cycle Specialization of Plant Cell Wall Degrading Enzymes in a Hemibiotrophic Pathogen

    PubMed Central

    Brunner, Patrick C.; Torriani, Stefano F.F.; Croll, Daniel; Stukenbrock, Eva H.; McDonald, Bruce A.

    2013-01-01

    Zymoseptoria tritici is an important fungal pathogen on wheat that originated in the Fertile Crescent. Its closely related sister species Z. pseudotritici and Z. ardabiliae infect wild grasses in the same region. This recently emerged host–pathogen system provides a rare opportunity to investigate the evolutionary processes shaping the genome of an emerging pathogen. Here, we investigate genetic signatures in plant cell wall degrading enzymes (PCWDEs) that are likely affected by or driving coevolution in plant-pathogen systems. We hypothesize four main evolutionary scenarios and combine comparative genomics, transcriptomics, and selection analyses to assign the majority of PCWDEs in Z. tritici to one of these scenarios. We found widespread differential transcription among different members of the same gene family, challenging the idea of functional redundancy and suggesting instead that specialized enzymatic activity occurs during different stages of the pathogen life cycle. We also find that natural selection has significantly affected at least 19 of the 48 identified PCWDEs. The majority of genes showed signatures of purifying selection, typical for the scenario of conserved substrate optimization. However, six genes showed diversifying selection that could be attributed to either host adaptation or host evasion. This study provides a powerful framework to better understand the roles played by different members of multigene families and to determine which genes are the most appropriate targets for wet laboratory experimentation, for example, to elucidate enzymatic function during relevant phases of a pathogen’s life cycle. PMID:23515261

  1. Structure, physicochemical properties and in vitro fermentation of enzymatically degraded cell wall materials from apples.

    PubMed

    Förster, S; Dongowski, G; Kunzek, H

    2002-06-01

    Cell wall materials (CWM) prepared from apple parenchyma tissue by treatment with commercial enzymes for maceration, mash fermentation and liquefaction were characterised with regard to their composition and structure as well as their physicochemical and physiological properties. Increasing enzymatic degradation of the CWM resulted in growing loss of the pectin matrix, decreasing porosity as well as increasing particle aggregation. Due to these structural alterations the water binding, the viscoelastic properties of the CWM-water-suspensions and the in vitro fermentation, forming short chain fatty acids, were reduced. The investigations showed that interrelations exist between enzymatic treatment and changes of (i) structure and state of matrices (evaluated by means of thermal analysis), (ii) physicochemical properties and (iii) physiological properties. So the application of liquefying enzymes can lead to a complete removal of the pectin matrix, causing an essentially improved thermal stability of the CWM preparation, but strongly reduced water binding and reduced structure-forming properties into the CWM-water-suspensions. The formation of short-chain fatty acids during in vitro fermentation of the CWM preparations by fresh human faeces flora depended on the portion and the state of the pectin matrix and the cellulose network, respectively.

  2. Suppression of Polyfluorene Photo-Oxidative Degradation via Encapsulation of Single-Walled Carbon Nanotubes.

    PubMed

    Luck, Kyle A; Arnold, Heather N; Shastry, Tejas A; Marks, Tobin J; Hersam, Mark C

    2016-10-10

    Polyfluorenes have achieved noteworthy performance in organic electronic devices, but exhibit undesired green band emission under photo-oxidative conditions that have limited their broad utility in optoelectronic applications. In addition, polyfluorenes are well-known dispersants of single-walled carbon nanotubes (SWCNTs), although the influence of SWCNTs on polyfluorene photo-oxidative stability has not yet been defined. Here we quantitatively explore the photophysical properties of poly[(9,9-bis(3/-(N,N-dimethylamino)propyl)-2,7-fluorene)-alt-2,7-(9,9-dioctylfluorene)] (PFN) under photo-oxidative conditions when it is in van der Waals contact with SWCNTs. Photoluminescence spectroscopy tracks the spectral evolution of the polymer emission following ambient ultraviolet (UV) exposure, confirming that PFN exhibits green band emission. In marked contrast, PFN-wrapped SWCNTs possess high spectral stability without green band emission under the same ambient UV exposure conditions. By investigating a series of PFN thin films as a function of SWCNT content, it is shown that SWCNT loadings as low as ~23 wt% suppress photo-oxidative degradation. These findings suggest that PFN-SWCNT composites provide an effective pathway toward utilizing polyfluorenes in organic optoelectronics.

  3. Manganese peroxidase degrades pristine but not surface-oxidized (carboxylated) single-walled carbon nanotubes.

    PubMed

    Zhang, Chengdong; Chen, Wei; Alvarez, Pedro J J

    2014-07-15

    The transformation of engineered nanomaterials in the environment can significantly affect their transport, fate, bioavailability, and toxicity. Little is known about the biotransformation potential of single-walled carbon nanotubes (SWNTs). In this study, we compared the enzymatic transformation of SWNTs and oxidized (carboxylated) SWNTs (O-SWNTs) using three ligninolytic enzymes: lignin peroxidase, manganese peroxidase (MnP), and laccase. Only MnP was capable of transforming SWNTs, as determined by Raman spectroscopy, near-infrared spectroscopy, and transmission electron microscopy. Interestingly, MnP degraded SWNTs but not O-SWNTs. The recalcitrance of O-SWNTs to enzymatic transformation is likely attributable to the binding of Mn2+ by their surface carboxyl groups at the enzyme binding site, which inhibits critical steps in the MnP catalytic cycle (i.e., Mn2+ oxidation and Mn3+ dissociation from the enzyme). Our results suggest that oxygen-containing surface functionalities do not necessarily facilitate the biodegradation of carbonaceous nanomaterials, as is commonly assumed.

  4. Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods. 3. Synthesis, characterization, and detection of different crystal forms of the chrome yellow pigment.

    PubMed

    Monico, Letizia; Janssens, Koen; Miliani, Costanza; Brunetti, Brunetto Giovanni; Vagnini, Manuela; Vanmeert, Frederik; Falkenberg, Gerald; Abakumov, Artem; Lu, Yinggang; Tian, He; Verbeeck, Johan; Radepont, Marie; Cotte, Marine; Hendriks, Ella; Geldof, Muriel; van der Loeff, Luuk; Salvant, Johanna; Menu, Michel

    2013-01-15

    The painter, Vincent van Gogh, and some of his contemporaries frequently made use of the pigment chrome yellow that is known to show a tendency toward darkening. This pigment may correspond to various chemical compounds such as PbCrO(4) and PbCr(1-x)S(x)O(4), that may each be present in various crystallographic forms with different tendencies toward degradation. Investigations by X-ray diffraction (XRD), mid-Fourier Transform infrared (FTIR), and Raman instruments (benchtop and portable) and synchrotron radiation-based micro-XRD and X-ray absorption near edge structure spectroscopy performed on oil-paint models, prepared with in-house synthesized PbCrO(4) and PbCr(1-x)S(x)O(4), permitted us to characterize the spectroscopic features of the various forms. On the basis of these results, an extended study has been carried out on historic paint tubes and on embedded paint microsamples taken from yellow-orange/pale yellow areas of 12 Van Gogh paintings, demonstrating that Van Gogh effectively made use of different chrome yellow types. This conclusion was also confirmed by in situ mid-FTIR investigations on Van Gogh's Portrait of Gauguin (Van Gogh Museum, Amsterdam).

  5. How endogenous plant cell-wall degradation mechanisms can help achieve higher efficiency in saccharification of biomass.

    PubMed

    Tavares, Eveline Q P; De Souza, Amanda P; Buckeridge, Marcos S

    2015-07-01

    Cell-wall recalcitrance to hydrolysis still represents one of the major bottlenecks for second-generation bioethanol production. This occurs despite the development of pre-treatments, the prospect of new enzymes, and the production of transgenic plants with less-recalcitrant cell walls. Recalcitrance, which is the intrinsic resistance to breakdown imposed by polymer assembly, is the result of inherent limitations in its three domains. These consist of: (i) porosity, associated with a pectin matrix impairing trafficking through the wall; (ii) the glycomic code, which refers to the fine-structural emergent complexity of cell-wall polymers that are unique to cells, tissues, and species; and (iii) cellulose crystallinity, which refers to the organization in micro- and/or macrofibrils. One way to circumvent recalcitrance could be by following cell-wall hydrolysis strategies underlying plant endogenous mechanisms that are optimized to precisely modify cell walls in planta. Thus, the cell-wall degradation that occurs during fruit ripening, abscission, storage cell-wall mobilization, and aerenchyma formation are reviewed in order to highlight how plants deal with recalcitrance and which are the routes to couple prospective enzymes and cocktail designs with cell-wall features. The manipulation of key enzyme levels in planta can help achieving biologically pre-treated walls (i.e. less recalcitrant) before plants are harvested for bioethanol production. This may be helpful in decreasing the costs associated with producing bioethanol from biomass. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  6. Electrochemical detection and degradation of ibuprofen from water on multi-walled carbon nanotubes-epoxy composite electrode.

    PubMed

    Motoc, Sorina; Remes, Adriana; Pop, Aniela; Manea, Florica; Schoonman, Joop

    2013-04-01

    This work describes the electrochemical behaviour of ibuprofen on two types of multi-walled carbon nanotubes based composite electrodes, i.e., multi-walled carbon nanotubes-epoxy (MWCNT) and silver-modified zeolite-multi-walled carbon nanotubes-epoxy (AgZMWCNT) composites electrodes. The composite electrodes were obtained using two-roll mill procedure. SEM images of surfaces of the composites revealed a homogeneous distribution of the composite components within the epoxy matrix. AgZMWCNT composite electrode exhibited the better electrical conductivity and larger electroactive surface area. The electrochemical determination of ibuprofen (IBP) was achieved using AgZMWCNT by cyclic voltammetry, differential-pulsed voltammetry, square-wave voltammetry and chronoamperometry. The IBP degradation occurred on both composite electrodes under controlled electrolysis at 1.2 and 1.75 V vs. Ag/AgCl, and IBP concentration was determined comparatively by differential-pulsed voltammetry, under optimized conditions using AgZMWCNT electrode and UV-Vis spectrophotometry methods to determine the IBP degradation performance for each electrode. AgZMWCNT electrode exhibited a dual character allowing a double application in IBP degradation process and its control.

  7. Dye Painting!

    ERIC Educational Resources Information Center

    Johnston, Ann

    This resource provides practical instructions for applying color and design directly to fabric. Basic information about the dye painting process is given. The guide addresses the technical aspects of fabric dye and color use and offers suggestions for fabric manipulation and dye application in order to achieve various design effects. This…

  8. Dye Painting!

    ERIC Educational Resources Information Center

    Johnston, Ann

    This resource provides practical instructions for applying color and design directly to fabric. Basic information about the dye painting process is given. The guide addresses the technical aspects of fabric dye and color use and offers suggestions for fabric manipulation and dye application in order to achieve various design effects. This…

  9. Perspective Painting.

    ERIC Educational Resources Information Center

    Gray, Joni

    2002-01-01

    One fourth grade class studied Van Gogh by investigating his art and life on the computer, painting still lifes, then learning to draw in perspective, creating colorful images of their own bedrooms using Van Gogh's bedroom as a model. Students extended their learning by examining relevant literature and completing timelines, biographical reports,…

  10. Ethylene-induced changes in lignification and cell wall-degrading enzymes in the roots of mungbean (Vigna radiata) sprouts.

    PubMed

    Huang, Wei-Na; Liu, Hong-Kai; Zhang, Hua-Hua; Chen, Zhen; Guo, Yang-Dong; Kang, Yu-Fan

    2013-12-01

    As an important regulator, ethylene inhibits root growth and development in plants. To determine the mechanism of ethylene on root elongation growth and lateral root formation, ethylene-induced lignification and cell wall-degrading enzymes in the roots of mungbean sprouts were tested. We initially observed that primary root elongation and lateral root numbers were inhibited, while lignin content was enhanced by ethephon (ETH). Cell wall remolding proteins, polygalacturonase (PG) and carboxymethyl cellulose (Cx) activities were reduced, but α-expansins and xyloglucan endotransglucosylases/hydrolases (XTH) were enhanced by ETH. The promotion in lignin production was correlated with changes in activities of key lignin biosynthesis enzymes and hydrogen peroxide (H2O2) content. These actions induced by ETH were altered via treatment with an ethylene perception antagonist (Ag+). We subsequently demonstrated that the role of endogenous ethylene in regulating root elongation growth and lateral root formation were correlated with lignification and cell wall-degrading enzymes, respectively. These results suggested that the ethylene-regulated inhibition of primary root elongation growth was caused by an increase in lignification that reinforced the cell wall and shortened root length, and the suppression of lateral root formation was linked to activities of PG, Cx, α-expansins and XTH. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  11. ASSOCIATION BETWEEN SPORULATION AND CELL-WALL DEGRADING ENZYMES IN THE WHEAT PATHOGEN MYCOSPHAERELLA GRAMINICOLA.

    PubMed

    Ors, M; Siah, A; Randoux, B; Selim, S; Couleaud, G; Maumene, C; Reignault, Ph; Halama, P

    2015-01-01

    Mycosphaerella graminicola is a hemibiotrophic fungus that causes Septoria tritici blotch (STB), one of the most serious foliar diseases of wheat. STB can occur with a wide range of disease levels on the host, which depend not only on the pathogenicity of fungal strains, but also on the resistance of host cultivars. Here, we investigated the association between the disease level and fungal cell-wall degrading enzyme and protease activities in three wheat cultivars differing in their resistance levels against M. graminicola. The experiments were carried out in the greenhouse using artificial inoculations with the M. graminicola strain T01193. Disease symptoms scored at 21-day post-inoculation (dpi) were significantly higher on the susceptible and moderately resistant cultivars, Alixan and Premio (48% and 42% of diseased leaf area, respectively), than in the resistant one, Altigo (28% of diseased leaf area). Regarding sporulation, the rate of pycnidial density was significantly higher on Alixan (2.9) compared to Premio and Altigo (1.1 and 1.0, respectively). Further biochemical investigations revealed, by 17 dpi, significant fungal beta-1,4-endoxylanase, beta-1,4-endoglucanase and protease activities, whose amounts increased according to the pycnidial density recorded on the infected leaves. At 21 dpi, the amounts of these activities were significantly higher on Alixan compared to Premio and Altigo (0.36 U/mg, 0.63 U/mg and 2.70 mU/mg total proteins on Alixan, 0.09 U/mg, 0.19 U/mg and 0.72 mU/mg total proteins on Premio and 0.05 U/mg, 0.15 U/mg and 0.52 mU/mg total proteins on Altigo for beta-1,4-endoxylanase, beta-1,4-endoglucanase and protease activities, respectively). These results confirm the importance of CWDE and protease activities in the process of fungal sporulation during the necrotrophic phase of M. graminicola.

  12. Assessment of dry-stone terrace wall degradation with a 3D approach

    NASA Astrophysics Data System (ADS)

    Djuma, Hakan; Camera, Corrado; Faka, Marina; Bruggeman, Adriana; Hermon, Sorin

    2016-04-01

    In the Mediterranean basin, terracing is a common element of agricultural lands. Terraces retained by dry-stone walls are used to conserve arable soil, delay erosion processes and retain rainfall runoff. Currently, agricultural land abandonment is widespread in the Mediterranean region leading to terrace wall failure due to lack of maintenance and consequently an increase in soil erosion. The objective of this study is to test the applicability of digital 3D documentation on mountainous agricultural areas for assessing changes in terrace wall geometry, including terrace wall failures and associated soil erosion. The study area is located at 800-1100 m above sea level, in the Ophiolite complex of the Troodos Mountains in Cyprus. Average annual precipitation is 750 mm. Two sites with dry-stone terraces were selected for this study. The first site had a sequence of three terrace walls that were surveyed. The uppermost terrace wall was collapsed at several locations; the middle at few locations; and the lowest was still intact. Three fieldwork campaigns were conducted at this site: during the dry season (initial conditions), the middle and end of the wet season. The second site had one terrace wall that was almost completely collapsed. This terrace was restored during a communal terrace rehabilitation event. Two fieldwork campaigns were conducted for this terrace: before and after the terrace wall restoration. Terrace walls were documented with a set of digital images, and transformed into a 3D point cloud (using web-based services and commercial software - Autodesk 123D catch and Menci Software uMap, respectively). A set of points, registered with the total station and geo-referenced with a GPS, enabled the scaling of the 3D model and aligning the terrace walls within the same reference system. The density (distance between each point) of the reconstructed point clouds is 0.005 m by Umap and 0.025 m by 123D Catch. On the first site, the model analysis identified wall

  13. Genome wide comprehensive analysis and web resource development on cell wall degrading enzymes from phyto-parasitic nematodes.

    PubMed

    Rai, Krishan Mohan; Balasubramanian, Vimal Kumar; Welker, Cassie Marie; Pang, Mingxiong; Hii, Mei Mei; Mendu, Venugopal

    2015-08-01

    The plant cell wall serves as a primary barrier against pathogen invasion. The success of a plant pathogen largely depends on its ability to overcome this barrier. During the infection process, plant parasitic nematodes secrete cell wall degrading enzymes (CWDEs) apart from piercing with their stylet, a sharp and hard mouthpart used for successful infection. CWDEs typically consist of cellulases, hemicellulases, and pectinases, which help the nematode to infect and establish the feeding structure or form a cyst. The study of nematode cell wall degrading enzymes not only enhance our understanding of the interaction between nematodes and their host, but also provides information on a novel source of enzymes for their potential use in biomass based biofuel/bioproduct industries. Although there is comprehensive information available on genome wide analysis of CWDEs for bacteria, fungi, termites and plants, but no comprehensive information available for plant pathogenic nematodes. Herein we have performed a genome wide analysis of CWDEs from the genome sequenced phyto pathogenic nematode species and developed a comprehensive publicly available database. In the present study, we have performed a genome wide analysis for the presence of CWDEs from five plant parasitic nematode species with fully sequenced genomes covering three genera viz. Bursaphelenchus, Glorodera and Meloidogyne. Using the Hidden Markov Models (HMM) conserved domain profiles of the respective gene families, we have identified 530 genes encoding CWDEs that are distributed among 24 gene families of glycoside hydrolases (412) and polysaccharide lyases (118). Furthermore, expression profiles of these genes were analyzed across the life cycle of a potato cyst nematode. Most genes were found to have moderate to high expression from early to late infectious stages, while some clusters were invasion stage specific, indicating the role of these enzymes in the nematode's infection and establishment process

  14. Insight into Enzymatic Degradation of Corn, Wheat, and Soybean Cell Wall Cellulose Using Quantitative Secretome Analysis of Aspergillus fumigatus.

    PubMed

    Sharma Ghimire, Prakriti; Ouyang, Haomiao; Wang, Qian; Luo, Yuanming; Shi, Bo; Yang, Jinghua; Lü, Yang; Jin, Cheng

    2016-12-02

    Lignocelluloses contained in animal forage cannot be digested by pigs or poultry with 100% efficiency. On contrary, Aspergillus fumigatus, a saprophytic filamentous fungus, is known to harbor 263 glycoside hydrolase encoding genes, suggesting that A. fumigatus is an efficient lignocellulose degrader. Hence the present study uses corn, wheat, or soybean as a sole carbon source to culture A. fumigatus under animal physiological condition to understand how cellulolytic enzymes work together to achieve an efficient degradation of lignocellulose. Our results showed that A. fumigatus produced different sets of enzymes to degrade lignocelluloses derived from corn, wheat, or soybean cell wall. In addition, the cellulolytic enzymes produced by A. fumigatus were stable under acidic condition or at higher temperatures. Using isobaric tags for a relative and absolute quantification (iTRAQ) approach, a total of ∼600 extracellular proteins were identified and quantified, in which ∼50 proteins were involved in lignocellulolysis, including cellulases, hemicellulases, lignin-degrading enzymes, and some hypothetical proteins. Data are available via ProteomeXchange with identifier PXD004670. On the basis of quantitative iTRAQ results, 14 genes were selected for further confirmation by RT-PCR. Taken together, our results indicated that the expression and regulation of lignocellulolytic proteins in the secretome of A. fumigatus were dependent on both nature and complexity of cellulose, thus suggesting that a different enzyme system is required for degradation of different lignocelluloses derived from plant cells. Although A. fumigatus is a pathogenic fungus and cannot be directly used as an enzyme source, as an efficient lignocellulose degrader its strategy to synergistically degrade various lignocelluloses with different enzymes can be used to design enzyme combination for optimal digestion and absorption of corn, wheat, or soybean that are used as forage of pig and poultry.

  15. Combined use of synchrotron radiation based micro-X-ray fluorescence, micro-X-ray diffraction, micro-X-ray absorption near-edge, and micro-fourier transform infrared spectroscopies for revealing an alternative degradation pathway of the pigment cadmium yellow in a painting by Van Gogh.

    PubMed

    Van der Snickt, Geert; Janssens, Koen; Dik, Joris; De Nolf, Wout; Vanmeert, Frederik; Jaroszewicz, Jacub; Cotte, Marine; Falkenberg, Gerald; Van der Loeff, Luuk

    2012-12-04

    Over the past years a number of studies have described the instability of the pigment cadmium yellow (CdS). In a previous paper we have shown how cadmium sulfide on paintings by James Ensor oxidizes to CdSO(4)·H(2)O. The degradation process gives rise to the fading of the bright yellow color and the formation of disfiguring white crystals that are present on the paint surface in approximately 50 μm sized globular agglomerations. Here, we study cadmium yellow in the painting "Flowers in a blue vase" by Vincent van Gogh. This painting differs from the Ensor case in the fact that (a) a varnish was superimposed onto the degraded paint surface and (b) the CdS paint area is entirely covered with an opaque crust. The latter obscures the yellow color completely and thus presents a seemingly more advanced state of degradation. Analysis of a cross-sectioned and a crushed sample by combining scanning microscopic X-ray diffraction (μ-XRD), microscopic X-ray absorption near-edge spectroscopy (μ-XANES), microscopic X-ray fluorescence (μ-XRF) based chemical state mapping and scanning microscopic Fourier transform infrared (μ-FT-IR) spectrometry allowed unravelling the complex alteration pathway. Although no crystalline CdSO(4) compounds were identified on the Van Gogh paint samples, we conclude that the observed degradation was initially caused by oxidation of the original CdS pigment, similar as for the previous Ensor case. However, due to the presence of an overlying varnish containing lead-based driers and oxalate ions, secondary reactions took place. In particular, it appears that upon the photoinduced oxidation of its sulfidic counterion, the Cd(2+) ions reprecipitated at the paint/varnish interface after having formed a complex with oxalate ions that themselves are considered to be degradation products of the resin and/or oil in the varnish. The SO(4)(2-) anions, for their part, found a suitable reaction partner in Pb(2+) ions stemming from a dissolved lead

  16. Simultaneous determination of pyridine-triphenylborane anti-fouling agent and its degradation products in paint-waste samples using capillary zone electrophoresis with field-amplified sample injection.

    PubMed

    Kaewchuay, Netnapit; Fukushi, Keiichi; Tsuboi, Ai; Okamura, Hideo; Saito, Keiitsu; Hirokawa, Takeshi

    2012-01-01

    We proposed a capillary zone electrophoresis (CZE) procedure using field-amplified sample injection (FASI) for the simultaneous determination of pyridine-triphenylborane (PTPB) and its degradation products: diphenylborinic acid (DPB), phenylboronic acid (MPB), and phenol. The LODs for PTPB, DPB, MPB, and phenol were, respectively, 0.85, 0.88, 44, and 28 μg L(-1). The RSDs (n = 4) for the analytes listed above were in respective ranges of 6.2 - 14, 5.9 - 10, and 0.49 - 0.62% for the peak area, peak height, and migration time. The compounds were extracted from paint-waste samples collected from shipyards using a siliga-gel column. The extract was dissolved with acetonitrile containing 1% (v/v) pyridine. The samples were then analyzed using CZE, revealing respective concentrations of 0.076 - 0.53, 0.015 - 0.36, 1.7 - 22, and 1.2 - 13 μg g(-1). The proposed FASI-CZE method is a simple and promising procedure that is expected to be useful for the determination of PTPB and its degradation products in paint wastes.

  17. Functional and modular analyses of diverse endoglucanases from Ruminococcus albus 8, a specialist plant cell wall degrading bacterium

    PubMed Central

    Iakiviak, Michael; Devendran, Saravanan; Skorupski, Anna; Moon, Young Hwan; Mackie, Roderick I.; Cann, Isaac

    2016-01-01

    Ruminococcus albus 8 is a specialist plant cell wall degrading ruminal bacterium capable of utilizing hemicellulose and cellulose. Cellulose degradation requires a suite of enzymes including endoglucanases, exoglucanases, and β-glucosidases. The enzymes employed by R. albus 8 in degrading cellulose are yet to be completely elucidated. Through bioinformatic analysis of a draft genome sequence of R. albus 8, seventeen putatively cellulolytic genes were identified. The genes were heterologously expressed in E. coli, and purified to near homogeneity. On biochemical analysis with cellulosic substrates, seven of the gene products (Ra0185, Ra0259, Ra0325, Ra0903, Ra1831, Ra2461, and Ra2535) were identified as endoglucanases, releasing predominantly cellobiose and cellotriose. Each of the R. albus 8 endoglucanases, except for Ra0259 and Ra0325, bound to the model crystalline cellulose Avicel, confirming functional carbohydrate binding modules (CBMs). The polypeptides for Ra1831 and Ra2535 were found to contain distantly related homologs of CBM65. Mutational analysis of residues within the CBM65 of Ra1831 identified key residues required for binding. Phylogenetic analysis of the endoglucanases revealed three distinct subfamilies of glycoside hydrolase family 5 (GH5). Our results demonstrate that this fibrolytic bacterium uses diverse GH5 catalytic domains appended with different CBMs, including novel forms of CBM65, to degrade cellulose. PMID:27439730

  18. Functional and modular analyses of diverse endoglucanases from Ruminococcus albus 8, a specialist plant cell wall degrading bacterium.

    PubMed

    Iakiviak, Michael; Devendran, Saravanan; Skorupski, Anna; Moon, Young Hwan; Mackie, Roderick I; Cann, Isaac

    2016-07-21

    Ruminococcus albus 8 is a specialist plant cell wall degrading ruminal bacterium capable of utilizing hemicellulose and cellulose. Cellulose degradation requires a suite of enzymes including endoglucanases, exoglucanases, and β-glucosidases. The enzymes employed by R. albus 8 in degrading cellulose are yet to be completely elucidated. Through bioinformatic analysis of a draft genome sequence of R. albus 8, seventeen putatively cellulolytic genes were identified. The genes were heterologously expressed in E. coli, and purified to near homogeneity. On biochemical analysis with cellulosic substrates, seven of the gene products (Ra0185, Ra0259, Ra0325, Ra0903, Ra1831, Ra2461, and Ra2535) were identified as endoglucanases, releasing predominantly cellobiose and cellotriose. Each of the R. albus 8 endoglucanases, except for Ra0259 and Ra0325, bound to the model crystalline cellulose Avicel, confirming functional carbohydrate binding modules (CBMs). The polypeptides for Ra1831 and Ra2535 were found to contain distantly related homologs of CBM65. Mutational analysis of residues within the CBM65 of Ra1831 identified key residues required for binding. Phylogenetic analysis of the endoglucanases revealed three distinct subfamilies of glycoside hydrolase family 5 (GH5). Our results demonstrate that this fibrolytic bacterium uses diverse GH5 catalytic domains appended with different CBMs, including novel forms of CBM65, to degrade cellulose.

  19. Painting models

    NASA Astrophysics Data System (ADS)

    Baart, F.; Donchyts, G.; van Dam, A.; Plieger, M.

    2015-12-01

    The emergence of interactive art has blurred the line between electronic, computer graphics and art. Here we apply this art form to numerical models. Here we show how the transformation of a numerical model into an interactive painting can both provide insights and solve real world problems. The cases that are used as an example include forensic reconstructions, dredging optimization, barrier design. The system can be fed using any source of time varying vector fields, such as hydrodynamic models. The cases used here, the Indian Ocean (HYCOM), the Wadden Sea (Delft3D Curvilinear), San Francisco Bay (3Di subgrid and Delft3D Flexible Mesh), show that the method used is suitable for different time and spatial scales. High resolution numerical models become interactive paintings by exchanging their velocity fields with a high resolution (>=1M cells) image based flow visualization that runs in a html5 compatible web browser. The image based flow visualization combines three images into a new image: the current image, a drawing, and a uv + mask field. The advection scheme that computes the resultant image is executed in the graphics card using WebGL, allowing for 1M grid cells at 60Hz performance on mediocre graphic cards. The software is provided as open source software. By using different sources for a drawing one can gain insight into several aspects of the velocity fields. These aspects include not only the commonly represented magnitude and direction, but also divergence, topology and turbulence .

  20. Electrochemical analysis of the alterations in copper pigments using charge transfer coefficient/peak potential diagrams. Application to microsamples of baroque wall paintings attached to polymer film electrodes.

    PubMed

    Doménech-Carbó, A; Doménech-Carbó, M T; Gimeno-Adelantado, J V; Bosch-Reig, F; Saurí-Peris, M C; Casas-Catalán, M J

    2001-04-01

    The alteration of copper pigments in art samples was studied by linear scan and cyclic voltammetry using sample-modified Elvacite 2044 film electrodes on the basis of two-dimensional diagrams of charge transfer coefficients calculated from Tafel plots of reductive dissolution processes vs. peak potential. Characteristic voltammetric peaks were obtained for pigments used in the baroque vault frescoes of the Basílica de la Virgen de los Desamparados painted by Antonio Palomino. Results obtained by voltammetric techniques were compared with those from SEM/EDX and FT-IR analysis obtaining a good agreement and leaving to an unambiguous identification of pigments used by Palomino and their alteration products.

  1. Plumbonacrite identified by X-ray powder diffraction tomography as a missing link during degradation of red lead in a Van Gogh painting.

    PubMed

    Vanmeert, Frederik; Van der Snickt, Geert; Janssens, Koen

    2015-03-16

    Red lead, a semiconductor pigment used by artists since antiquity, is known to undergo several discoloration phenomena. These transformations are either described as darkening of the pigment caused by the formation of either plattnerite (β-PbO2) or galena (PbS) or as whitening by which red lead is converted into anglesite (PbSO4) or (hydro)cerussite (2 PbCO3⋅Pb(OH)2; PbCO3). X-ray powder diffraction tomography, a powerful analytical method that allows visualization of the internal distribution of different crystalline compounds in complex samples, was used to investigate a microscopic paint sample from a Van Gogh painting. A very rare lead mineral, plumbonacrite (3 PbCO3⋅Pb(OH)2⋅PbO), was revealed to be present. This is the first reported occurrence of this compound in a painting dating from before the mid 20th century. It constitutes the missing link between on the one hand the photoinduced reduction of red lead and on the other hand (hydro)cerussite, and thus sheds new light on the whitening of red lead. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. PEGylated single-walled carbon nanotubes activate neutrophils to increase production of hypochlorous acid, the oxidant capable of degrading nanotubes.

    PubMed

    Vlasova, Irina I; Vakhrusheva, Tatyana V; Sokolov, Alexey V; Kostevich, Valeria A; Gusev, Alexandr A; Gusev, Sergey A; Melnikova, Viktoriya I; Lobach, Anatolii S

    2012-10-01

    Perspectives for the use of carbon nanotubes in biomedical applications depend largely on their ability to degrade in the body into products that can be easily cleared out. Carboxylated single-walled carbon nanotubes (c-SWCNTs) were shown to be degraded by oxidants generated by peroxidases in the presence of hydrogen peroxide. In the present study we demonstrated that conjugation of poly(ethylene glycol) (PEG) to c-SWCNTs does not interfere with their degradation by peroxidase/H(2)O(2) system or by hypochlorite. Comparison of different heme-containing proteins for their ability to degrade PEG-SWCNTs has led us to conclude that the myeloperoxidase (MPO) product hypochlorous acid (HOCl) is the major oxidant that may be responsible for biodegradation of PEG-SWCNTs in vivo. MPO is secreted mainly by neutrophils upon activation. We hypothesize that SWCNTs may enhance neutrophil activation and therefore stimulate their own biodegradation due to MPO-generated HOCl. PEG-SWCNTs at concentrations similar to those commonly used in in vivo studies were found to activate isolated human neutrophils to produce HOCl. Both PEG-SWCNTs and c-SWCNTs enhanced HOCl generation from isolated neutrophils upon serum-opsonized zymosan stimulation. Both types of nanotubes were also found to activate neutrophils in whole blood samples. Intraperitoneal injection of a low dose of PEG-SWCNTs into mice induced an increase in percentage of circulating neutrophils and activation of neutrophils and macrophages in the peritoneal cavity, suggesting the evolution of an inflammatory response. Activated neutrophils can produce high local concentrations of HOCl, thereby creating the conditions favorable for degradation of the nanotubes.

  3. Combining proteomics and transcriptome sequencing to identify active plant-cell-wall-degrading enzymes in a leaf beetle

    PubMed Central

    2012-01-01

    Background The primary plant cell wall is a complex mixture of polysaccharides and proteins encasing living plant cells. Among these polysaccharides, cellulose is the most abundant and useful biopolymer present on earth. These polysaccharides also represent a rich source of energy for organisms which have evolved the ability to degrade them. A growing body of evidence suggests that phytophagous beetles, mainly species from the superfamilies Chrysomeloidea and Curculionoidea, possess endogenous genes encoding complex and diverse families of so-called plant cell wall degrading enzymes (PCWDEs). The presence of these genes in phytophagous beetles may have been a key element in their success as herbivores. Here, we combined a proteomics approach and transcriptome sequencing to identify PCWDEs present in larval gut contents of the mustard leaf beetle, Phaedon cochleariae. Results Using a two-dimensional proteomics approach, we recovered 11 protein bands, isolated using activity assays targeting cellulose-, pectin- and xylan-degrading enzymes. After mass spectrometry analyses, a total of 13 proteins putatively responsible for degrading plant cell wall polysaccharides were identified; these proteins belong to three glycoside hydrolase (GH) families: GH11 (xylanases), GH28 (polygalacturonases or pectinases), and GH45 (β-1,4-glucanases or cellulases). Additionally, highly stable and proteolysis-resistant host plant-derived proteins from various pathogenesis-related protein (PRs) families as well as polygalacturonase-inhibiting proteins (PGIPs) were also identified from the gut contents proteome. In parallel, transcriptome sequencing revealed the presence of at least 19 putative PCWDE transcripts encoded by the P. cochleariae genome. All of these were specifically expressed in the insect gut rather than the rest of the body, and in adults as well as larvae. The discrepancy observed in the number of putative PCWDEs between transcriptome and proteome analyses could be

  4. Painted Saturn

    NASA Image and Video Library

    2014-09-29

    Saturn many cloud patterns, swept along by high-speed winds, look as if they were painted on by some eager alien artist in this image from NASA Cassini spacecraft. With no real surface features to slow them down, wind speeds on Saturn can top 1,100 mph (1,800 kph), more than four times the top speeds on Earth. This view looks toward the sunlit side of the rings from about 29 degrees above the ringplane. The image was taken with the Cassini spacecraft wide-angle camera on April 4, 2014 using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 752 nanometers. The view was obtained at a distance of approximately 1.1 million miles (1.8 million kilometers) from Saturn. Image scale is 68 miles (109 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA18280

  5. Activating Intrinsic Carbohydrate-Active Enzymes of the Smut Fungus Ustilago maydis for the Degradation of Plant Cell Wall Components

    PubMed Central

    Geiser, Elena; Reindl, Michèle; Blank, Lars M.; Feldbrügge, Michael

    2016-01-01

    ABSTRACT The microbial conversion of plant biomass to valuable products in a consolidated bioprocess could greatly increase the ecologic and economic impact of a biorefinery. Current strategies for hydrolyzing plant material mostly rely on the external application of carbohydrate-active enzymes (CAZymes). Alternatively, production organisms can be engineered to secrete CAZymes to reduce the reliance on externally added enzymes. Plant-pathogenic fungi have a vast repertoire of hydrolytic enzymes to sustain their lifestyle, but expression of the corresponding genes is usually highly regulated and restricted to the pathogenic phase. Here, we present a new strategy in using the biotrophic smut fungus Ustilago maydis for the degradation of plant cell wall components by activating its intrinsic enzyme potential during axenic growth. This fungal model organism is fully equipped with hydrolytic enzymes, and moreover, it naturally produces value-added substances, such as organic acids and biosurfactants. To achieve the deregulated expression of hydrolytic enzymes during the industrially relevant yeast-like growth in axenic culture, the native promoters of the respective genes were replaced by constitutively active synthetic promoters. This led to an enhanced conversion of xylan, cellobiose, and carboxymethyl cellulose to fermentable sugars. Moreover, a combination of strains with activated endoglucanase and β-glucanase increased the release of glucose from carboxymethyl cellulose and regenerated amorphous cellulose, suggesting that mixed cultivations could be a means for degrading more complex substrates in the future. In summary, this proof of principle demonstrates the potential applicability of activating the expression of native CAZymes from phytopathogens in a biocatalytic process. IMPORTANCE This study describes basic experiments that aim at the degradation of plant cell wall components by the smut fungus Ustilago maydis. As a plant pathogen, this fungus contains a

  6. A holistic approach towards assessment of severity of land degradation along the Great Wall in northern Shaanxi Province, China.

    PubMed

    Liu, Yansui; Gao, Jay; Yang, Yanfeng

    2003-03-01

    The farming and grazing interlocked transitional zone along the Great Wall in northern Shaanxi Province is particularly vulnerable to desertification due to its fragile ecosystem and intensive human activity. Studies reveal that desertification is both a natural and anthropogenic process. Four desertification indicators (vegetative cover, proportion of drifting sand area, desertification rate, and population pressure) were used to assess the severity of desertification in a GIS. The first three factors were derived from multitemporal remote sensing and land inventory data. The last factor was calculated from census data. It was found that the overall severity of land degradation in the study area has worsened during the last two decades with severely, highly and moderately degraded land accounting for 84.2% of the total area in 1998. While the area affected by desertification has increased, the rate of desertification has also accelerated from 0.74 to 0.87%. Risk of land degradation in the study area has increased, on an average, by 155% since 1985. Incorporation of both natural and anthropogenic factors in the analysis provides realistic assessment of risk of desertification.

  7. Sonochemical Degradation of Reactive Black 5 with a Composite Catalyst of TiO2/Single-Walled Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    Cho, Eunju; Choi, Jongbok; Lee, Yonghyeon; Park, Jeong Min; Khim, Jeehyeong

    2013-07-01

    In the sonocatalytic process, composites of TiO2-carbon were used because carbon provides more adsorption sites and acts like an electron sink to prevent the recombination of an electron/hole. Therefore, in the present study, the characteristics of a TiO2/single-walled carbon nanotubes catalyst (TiO2/SWCNTs) have been investigated, and the optimal weight ratio of SWCNTs and the dose for degradation of reactive black 5 (RB5) were also evaluated. TiO2/SWCNT composite was characterized using Brunauer-Emmett-Teller analysis, scanning electron microscopy, energy-dispersive X-ray diffraction microanalysis and spectra, and X-ray diffraction patterns. The degradation rate constants of RB5 with the ratio of SWCNTs were found to depend on the adsorption phenomenon of a surface catalyst, light absorbance, and the recombination of electrons and holes. As a result, the optimal ratio of carbon in the sono-TiO2/SWCNTs process for degradation of RB5 was TiO2:SWCNTs= 200:1. Additionally, the optimal dose of the catalyst was 0.5 g/L.

  8. Examinations of a new long-term degradable electrospun polycaprolactone scaffold in three rat abdominal wall models.

    PubMed

    Jangö, Hanna; Gräs, Søren; Christensen, Lise; Lose, Gunnar

    2017-02-01

    Alternative approaches to reinforce native tissue in reconstructive surgery for pelvic organ prolapse are warranted. Tissue engineering combines the use of a scaffold with the regenerative potential of stem cells and is a promising new concept in urogynecology. Our objective was to evaluate whether a newly developed long-term degradable polycaprolactone scaffold could provide biomechanical reinforcement and function as a scaffold for autologous muscle fiber fragments. We performed a study with three different rat abdominal wall models where the scaffold with or without muscle fiber fragments was placed (1) subcutaneously (minimal load), (2) in a partial defect (partial load), and (3) in a full-thickness defect (heavy load). After 8 weeks, no animals had developed hernia, and the scaffold provided biomechanical reinforcement, even in the models where it was subjected to heavy load. The scaffold was not yet degraded but showed increased thickness in all groups. Histologically, we found a massive foreign body response with numerous large giant cells intermingled with the fibers of the scaffold. Cells from added muscle fiber fragments could not be traced by PKH26 fluorescence or desmin staining. Taken together, the long-term degradable polycaprolactone scaffold provided biomechanical reinforcement by inducing a marked foreign-body response and attracting numerous inflammatory cells to form a strong neo-tissue construct. However, cells from the muscle fiber fragments did not survive in this milieu. Properties of the new neo-tissue construct must be evaluated at the time of full degradation of the scaffold before its possible clinical value in pelvic organ prolapse surgery can be evaluated.

  9. Assessing performance of painted carbon and weathering steels in an industrial atmosphere

    SciTech Connect

    Wang, J.H.; Shih, H.C.; Wei, F.I.

    1997-03-01

    Protective properties and electrochemical impedance characteristics of four painted steels were investigated after outdoor exposure for 6 years and laboratory-based immersion tests. Results were compared to evaluate performance of the two paint systems for different steel substrates. The silicate-type primer/epoxy-based micaceous iron oxide (MIO) paint/polyurethane topcoat system showed better performance than the epoxy-type primer/epoxy-based MIO paint/polyvinyl chloride (PVC) topcoat system. The former paint system showed better topcoat protection and more effective cathodic protection (CP) provided by the zinc-rich primer. Two forms of paint degradation, blistering and pore attack, were observed. Paint degradation was correlated with changes in paint resistance and the breakpoint frequency of impedance data. Based upon visual observation and changes in impedance characteristics, two impedance models were proposed to explain the paint degradation.

  10. Degradation of wheat straw cell wall by white rot fungi Phanerochaete chrysosporium

    NASA Astrophysics Data System (ADS)

    Zeng, Jijiao

    The main aim of this dissertation research was to understand the natural microbial degradation process of lignocellulosic materials in order to develop a new, green and more effective pretreatment technology for bio-fuel production. The biodegradation of wheat straw by white rot fungi Phanerochaete chrysosporium was investigated. The addition of nutrients significantly improved the performance of P.chrysosporium on wheat straw degradation. The proteomic analysis indicated that this fungus produced various pepetides related to cellulose and lignin degradation while grown on the biomass. The structural analysis of lignin further showed that P.chrysosporium preferentially degraded hydroxycinnamtes in order to access cellulose. In details, the effects of carbon resource and metabolic pathway regulating compounds on manganeses peroxidase (MnP) were studied. The results indicated that MnP activity of 4.7 +/- 0.31 U mL-1 was obtained using mannose as a carbon source. The enzyme productivity further reached 7.36 +/- 0.05 U mL-1 and 8.77 +/- 0.23 U mL -1 when the mannose medium was supplemented with cyclic adenosine monophosphate (cAMP) and S-adenosylmethionine (SAM) respectively, revealing highest MnP productivity obtained by optimizing the carbon sources and supplementation with small molecules. In addition, the effects of nutrient additives for improving biological pretreatment of lignocellulosic biomass were studied. The pretreatment of wheat straw supplemented with inorganic salts (salts group) and tween 80 was examined. The extra nutrient significantly improved the ligninase expression leading to improve digestibility of lignocellulosic biomass. Among the solid state fermentation groups, salts group resulted in a substantial degradation of wheat straw within one week, along with the highest lignin loss (25 %) and ˜ 250% higher efficiency for the total sugar release through enzymatic hydrolysis. The results were correlated with pyrolysis GC-MS (Py

  11. PEGylated single-walled carbon nanotubes activate neutrophils to increase production of hypochlorous acid, the oxidant capable of degrading nanotubes

    SciTech Connect

    Vlasova, Irina I.; Vakhrusheva, Tatyana V.; Sokolov, Alexey V.; Kostevich, Valeria A.; Gusev, Alexandr A.; Gusev, Sergey A.; Melnikova, Viktoriya I.; Lobach, Anatolii S.

    2012-10-01

    Perspectives for the use of carbon nanotubes in biomedical applications depend largely on their ability to degrade in the body into products that can be easily cleared out. Carboxylated single-walled carbon nanotubes (c-SWCNTs) were shown to be degraded by oxidants generated by peroxidases in the presence of hydrogen peroxide. In the present study we demonstrated that conjugation of poly(ethylene glycol) (PEG) to c-SWCNTs does not interfere with their degradation by peroxidase/H{sub 2}O{sub 2} system or by hypochlorite. Comparison of different heme-containing proteins for their ability to degrade PEG-SWCNTs has led us to conclude that the myeloperoxidase (MPO) product hypochlorous acid (HOCl) is the major oxidant that may be responsible for biodegradation of PEG-SWCNTs in vivo. MPO is secreted mainly by neutrophils upon activation. We hypothesize that SWCNTs may enhance neutrophil activation and therefore stimulate their own biodegradation due to MPO-generated HOCl. PEG-SWCNTs at concentrations similar to those commonly used in in vivo studies were found to activate isolated human neutrophils to produce HOCl. Both PEG-SWCNTs and c-SWCNTs enhanced HOCl generation from isolated neutrophils upon serum-opsonized zymosan stimulation. Both types of nanotubes were also found to activate neutrophils in whole blood samples. Intraperitoneal injection of a low dose of PEG-SWCNTs into mice induced an increase in percentage of circulating neutrophils and activation of neutrophils and macrophages in the peritoneal cavity, suggesting the evolution of an inflammatory response. Activated neutrophils can produce high local concentrations of HOCl, thereby creating the conditions favorable for degradation of the nanotubes. -- Highlights: ► Myeloperoxidase (MPO) product hypochlorous acid is able to degrade CNTs. ► PEGylated SWCNTs stimulate isolated neutrophils to produce hypochlorous acid. ► SWCNTs are capable of activating neutrophils in blood samples. ► Activation of

  12. A Cell Wall-degrading Endopolygalacturonase Secreted by Colletotrichum lindemuthianum1

    PubMed Central

    English, Patricia D.; Maglothin, Austin; Keegstra, Kenneth; Albersheim, Peter

    1972-01-01

    Cultures of Colletotrichum lindemuthianum (Saccardo and Magnus) Scribner have been induced to secrete an endopolygalacturonase (polygalacturonide glycanohydrolase EC3.2. 1.15). This enzyme has been brought to a high state of purity by ion exchange, gel filtration, and agarose affinity chromatography. The enzyme has optimal activity at pH 5, has an apparent molecular weight as determined by gel filtration of about 70,000, and prefers polygalacturonic acid to pectin as its substrate. The enzyme, while hydrolyzing only 1% of the glycosidic bonds, reduces the viscosity of a polygalacturonic solution by 50%. Nevertheless, the initial as well as the final products of polygalacturonic acid hydrolysis are predominantly tri- and digalacturonic acid and, to a lesser extent, monogalacturonic acid. The purified enzyme catalyzes the removal of about 80% of the galacturonic acid residues of cell walls isolated from suspension-cultured sycamore cells (Acer pseudoplatanus) as well as from the walls isolated from 8-day-old Red Kidney bean (Phaseolus vulgaris) hypocotyls. PMID:16657947

  13. Mycoparasitism studies of Trichoderma harzianum against Sclerotinia sclerotiorum: evaluation of antagonism and expression of cell wall-degrading enzymes genes.

    PubMed

    Troian, Rogério Fraga; Steindorff, Andrei Stecca; Ramada, Marcelo Henrique Soller; Arruda, Walquiria; Ulhoa, Cirano José

    2014-10-01

    Trichoderma spp. are known for their biocontrol activity against several plant pathogens. A specific isolate of Trichoderma harzianum, 303/02, has the potential to inhibit the growth of Sclerotinia sclerotiorum, an important agent involved in several crop diseases. In this study, the interaction between T. harzianum 303/02 and mycelia, sclerotia and apothecia of S. sclerotiorum was studied by scanning electron microscopy. RT-qPCR was used to examine the expression of 11 genes potentially involved in biocontrol. T. harzianum 303/02 parasitizes S. sclerotiorum by forming branches that coil around the hyphae. The fungus multiplied abundantly at the sclerotia and apothecia surface, forming a dense mycelium that penetrated the inner surface of these structures. The levels of gene expression varied according to the type of structure with which T. harzianum was interacting. The data also showed the presence of synergistic action between the cell-wall degrading enzymes.

  14. Adaptive expression of host cell wall degrading enzymes in fungal disease: an example from Fusarium root rot of medicinal Coleus.

    PubMed

    Bhattacharya, A

    2013-12-15

    Quantity of extracellular proteins and activities two cell wall degrading enzymes pectinase and cellulase were determined in the culture filtrate of Fusarium solani, the causal organism of root rot of Coleus forskohlii. Substitution of carbon source in the medium with either pectin or carboxymethyl cellulose led to the increased production of extracellular proteins by the fungus. Pectinase and cellulase activity in the culture filtrate was detected only when the growth medium contained substituted carbon source in the form of pectin and CMC, respectively. Pectinase activity was highest after 5 days incubation and then decreased gradually with time but cellulase activity showed a steady time dependent increase. In vitro virulence study showed the requirement of both the enzymes for complete expression of rot symptoms on Coleus plants. Thus the present study established the adaptive, substrate dependent expression of the two enzymes by the fungus and also their involvement in the root rot disease of Coleus forskohlii.

  15. Methane Painting

    NASA Image and Video Library

    2015-09-07

    Why does Saturn look like it's been painted with a dark brush in this infrared image, but Dione looks untouched? Perhaps an artist with very specific tastes in palettes? The answer is methane. This image was taken in a wavelength that is absorbed by methane. Dark areas seen here on Saturn are regions with thicker clouds, where light has to travel through more methane on its way into and back out of the atmosphere. Since Dione (698 miles or 1,123 kilometers across) doesn't have an atmosphere rich in methane the way Saturn does, it does not experience similar absorption -- the sunlight simply bounces off its icy surface. Shadows of the rings are seen cast onto the planet at lower right. This view looks toward Saturn from the unilluminated side of the rings, about 0.3 degrees below the ring plane. The image was taken with the Cassini spacecraft wide-angle camera on May 27, 2015 using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 728 nanometers. http://photojournal.jpl.nasa.gov/catalog/PIA18336

  16. Mixing Paints

    NASA Image and Video Library

    2014-11-17

    Nature is an artist, and this time she seems to have let her paints swirl together a bit. What the viewer might perceive to be Saturn's surface is really just the tops of its uppermost cloud layers. Everything we see is the result of fluid dynamics. Astronomers study Saturn's cloud dynamics in part to test and improve our understanding of fluid flows. Hopefully, what we learn will be useful for understanding our own atmosphere and that of other planetary bodies. This view looks toward the sunlit side of the rings from about 25 degrees above the ringplane. The image was taken in red light with the Cassini spacecraft narrow-angle camera on Aug. 23, 2014. The view was obtained at a distance of approximately 1.1 million miles (1.7 million kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 23 degrees. Image scale is 63 miles (102 kilometers) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA18290

  17. Crystal and cryoEM structural studies of a cell wall degrading enzyme in the bacteriophage [psi]29 tail

    SciTech Connect

    Xiang, Ye; Morais, Marc C.; Cohen, Daniel N.; Bowman, Valorie D.; Anderson, Dwight L.; Rossmann, Michael G.

    2009-08-28

    The small bacteriophage {phi}29 must penetrate the {approx}250-{angstrom} thick external peptidoglycan cell wall and cell membrane of the Gram-positive Bacillus subtilis, before ejecting its dsDNA genome through its tail into the bacterial cytoplasm. The tail of bacteriophage {phi}29 is noncontractile and {approx}380 {angstrom} long. A 1.8-{angstrom} resolution crystal structure of gene product 13 (gp13) shows that this tail protein has spatially well separated N- and C-terminal domains, whose structures resemble lysozyme-like enzymes and metallo-endopeptidases, respectively. CryoEM reconstructions of the WT bacteriophage and mutant bacteriophages missing some or most of gp13 shows that this enzyme is located at the distal end of the {phi}29 tail knob. This finding suggests that gp13 functions as a tail-associated, peptidoglycan-degrading enzyme able to cleave both the polysaccharide backbone and peptide cross-links of the peptidoglycan cell wall. Comparisons of the gp13{sup -} mutants with the {phi}29 mature and emptied phage structures suggest the sequence of events that occur during the penetration of the tail through the peptidoglycan layer.

  18. Response Mechanisms of Bacterial Degraders to Environmental Contaminants on the Level of Cell Walls and Cytoplasmic Membrane

    PubMed Central

    2014-01-01

    Bacterial strains living in the environment must cope with the toxic compounds originating from humans production. Surface bacterial structures, cell wall and cytoplasmic membrane, surround each bacterial cell and create selective barriers between the cell interior and the outside world. They are a first site of contact between the cell and toxic compounds. Organic pollutants are able to penetrate into cytoplasmic membrane and affect membrane physiological functions. Bacteria had to evolve adaptation mechanisms to counteract the damage originated from toxic contaminants and to prevent their accumulation in cell. This review deals with various adaptation mechanisms of bacterial cell concerning primarily the changes in cytoplasmic membrane and cell wall. Cell adaptation maintains the membrane fluidity status and ratio between bilayer/nonbilayer phospholipids as well as the efflux of toxic compounds, protein repair mechanisms, and degradation of contaminants. Low energy consumption of cell adaptation is required to provide other physiological functions. Bacteria able to survive in toxic environment could help us to clean contaminated areas when they are used in bioremediation technologies. PMID:25057269

  19. Production of a cell wall-associated endopolygalacturonase by Colletotrichum lindemuthianum and pectin degradation during bean infection.

    PubMed

    Herbert, Corentin; O'Connell, Richard; Gaulin, Elodie; Salesses, Vincent; Esquerré-Tugayé, Marie Thérèse; Dumas, Bernard

    2004-02-01

    The bean pathogen Colletotrichum lindemuthianum expresses two endopolygalacturonase genes, CLPG1 and CLPG2, during interaction with its host plant. However, only CLPG1 was found to be secreted to the extracellular medium during saprophytic growth of the fungus on pectin. To localize CLPG2, a FLAG epitope sequence was inserted in the C-terminal sequence of CLPG2 and the modified gene was introduced into C. lindemuthianum. Western blot analysis using a FLAG monoclonal antibody allowed the detection of CLPG2 in intracellular protein extracts and in the cell wall fraction, but not in the culture medium. Indirect immunofluorescence microscopy was performed to detect CLPG2 during saprophytic or parasitic growth. According to the expression pattern of CLPG2, it was found that CLPG2 accumulates in the fungal cell wall during growth on pectin medium and during appressorium formation, both in vitro and during interaction with the plant. Pectin degradation was not detected around the infection peg using the monoclonal antibody JIM7, specific for methyl-esterified galacturonan. However, extensive pectin dissolution was observed during the development of secondary hyphae.

  20. Fungal plant cell wall-degrading enzyme database: a platform for comparative and evolutionary genomics in fungi and Oomycetes

    PubMed Central

    2013-01-01

    Background Plant cell wall-degrading enzymes (PCWDEs) play significant roles throughout the fungal life including acquisition of nutrients and decomposition of plant cell walls. In addition, many of PCWDEs are also utilized by biofuel and pulp industries. In order to develop a comparative genomics platform focused in fungal PCWDEs and provide a resource for evolutionary studies, Fungal PCWDE Database (FPDB) is constructed (http://pcwde.riceblast.snu.ac.kr/). Results In order to archive fungal PCWDEs, 22 sequence profiles were constructed and searched on 328 genomes of fungi, Oomycetes, plants and animals. A total of 6,682 putative genes encoding PCWDEs were predicted, showing differential distribution by their life styles, host ranges and taxonomy. Genes known to be involved in fungal pathogenicity, including polygalacturonase (PG) and pectin lyase, were enriched in plant pathogens. Furthermore, crop pathogens had more PCWDEs than those of rot fungi, implying that the PCWDEs analysed in this study are more needed for invading plant hosts than wood-decaying processes. Evolutionary analysis of PGs in 34 selected genomes revealed that gene duplication and loss events were mainly driven by taxonomic divergence and partly contributed by those events in species-level, especially in plant pathogens. Conclusions The FPDB would provide a fungi-specialized genomics platform, a resource for evolutionary studies of PCWDE gene families and extended analysis option by implementing Favorite, which is a data exchange and analysis hub built in Comparative Fungal Genomics Platform (CFGP 2.0; http://cfgp.snu.ac.kr/). PMID:24564786

  1. Fungal plant cell wall-degrading enzyme database: a platform for comparative and evolutionary genomics in fungi and Oomycetes.

    PubMed

    Choi, Jaeyoung; Kim, Ki-Tae; Jeon, Jongbum; Lee, Yong-Hwan

    2013-01-01

    Plant cell wall-degrading enzymes (PCWDEs) play significant roles throughout the fungal life including acquisition of nutrients and decomposition of plant cell walls. In addition, many of PCWDEs are also utilized by biofuel and pulp industries. In order to develop a comparative genomics platform focused in fungal PCWDEs and provide a resource for evolutionary studies, Fungal PCWDE Database (FPDB) is constructed (http://pcwde.riceblast.snu.ac.kr/). In order to archive fungal PCWDEs, 22 sequence profiles were constructed and searched on 328 genomes of fungi, Oomycetes, plants and animals. A total of 6,682 putative genes encoding PCWDEs were predicted, showing differential distribution by their life styles, host ranges and taxonomy. Genes known to be involved in fungal pathogenicity, including polygalacturonase (PG) and pectin lyase, were enriched in plant pathogens. Furthermore, crop pathogens had more PCWDEs than those of rot fungi, implying that the PCWDEs analysed in this study are more needed for invading plant hosts than wood-decaying processes. Evolutionary analysis of PGs in 34 selected genomes revealed that gene duplication and loss events were mainly driven by taxonomic divergence and partly contributed by those events in species-level, especially in plant pathogens. The FPDB would provide a fungi-specialized genomics platform, a resource for evolutionary studies of PCWDE gene families and extended analysis option by implementing Favorite, which is a data exchange and analysis hub built in Comparative Fungal Genomics Platform (CFGP 2.0; http://cfgp.snu.ac.kr/).

  2. Erosion of root epidermal cell walls by Rhizobium polysaccharide-degrading enzymes as related to primary host infection in the Rhizobium-legume symbiosis.

    PubMed

    Mateos, P F; Baker, D L; Petersen, M; Velázquez, E; Jiménez-Zurdo, J I; Martínez-Molina, E; Squartini, A; Orgambide, G; Hubbell, D H; Dazzo, F B

    2001-06-01

    A central event of the infection process in the Rhizobium-legume symbiosis is the modification of the host cell wall barrier to form a portal of entry large enough for bacterial penetration. Transmission electron microscopy (TEM) indicates that rhizobia enter the legume root hair through a completely eroded hole that is slightly larger than the bacterial cell and is presumably created by localized enzymatic hydrolysis of the host cell wall. In this study, we have used microscopy and enzymology to further clarify how rhizobia modify root epidermal cell walls to shed new light on the mechanism of primary host infection in the Rhizobium-legume symbiosis. Quantitative scanning electron microscopy indicated that the incidence of highly localized, partially eroded pits on legume root epidermal walls that follow the contour of the rhizobial cell was higher in host than in nonhost legume combinations, was inhibited by high nitrate supply, and was not induced by immobilized wild-type chitolipooligosaccharide Nod factors reversibly adsorbed to latex beads. TEM examination of these partially eroded, epidermal pits indicated that the amorphous, noncrystalline portions of the wall were disrupted, whereas the crystalline portions remained ultrastructurally intact. Further studies using phase-contrast and polarized light microscopy indicated that (i) the structural integrity of clover root hair walls is dependent on wall polymers that are valid substrates for cell-bound polysaccharide-degrading enzymes from rhizobia, (ii) the major site where these rhizobial enzymes can completely erode the root hair wall is highly localized at the isotropic, noncrystalline apex of the root hair tip, and (iii) the degradability of clover root hair walls by rhizobial polysaccharide-degrading enzymes is enhanced by modifications induced during growth in the presence of chitolipooligosaccharide Nod factors from wild-type clover rhizobia. The results suggest a complementary role of rhizobial cell

  3. AepA of Pectobacterium is not involved in the regulation of extracellular plant cell wall degrading enzymes production.

    PubMed

    Kõiv, Viia; Andresen, Liis; Mäe, Andres

    2010-06-01

    Plant cell wall degrading enzymes (PCWDE) are the major virulence determinants in phytopathogenic Pectobacterium, and their production is controlled by many regulatory factors. In this study, we focus on the role of the AepA protein, which was previously described to be a global regulator of PCWDE production in Pectobacterium carotovorum (Murata et al. in Mol Plant Microbe Interact 4:239-246, 1991). Our results show that neither inactivation nor overexpression of aepA affects PCWDE production in either Pectobacterium atrosepticum SCRI1043 or Pectobacterium carotovorum subsp. carotovorum SCC3193. The previously published observation based on the overexpression of aepA could be explained by the presence of the adjacent regulatory rsmB gene in the constructs used. Our database searches indicated that AepA belongs to the YtcJ subfamily of amidohydrolases. YtcJ-like amidohydrolases are present in bacteria, archaea, plants and some fungi. Although AepA has 28% identity with the formamide deformylase NfdA in Arthrobacter pascens F164, AepA was unable to catalyze the degradation of NdfA-specific N-substituted formamides. We conclude that AepA is a putative aminohydrolase not involved in regulation of PCWDE production.

  4. Identification and expression profiling of novel plant cell wall degrading enzymes from a destructive pest of palm trees, Rhynchophorus ferrugineus.

    PubMed

    Antony, B; Johny, J; Aldosari, S A; Abdelazim, M M

    2017-08-01

    Plant cell wall degrading enzymes (PCWDEs) from insects were recently identified as a multigene family of proteins that consist primarily of glycoside hydrolases (GHs) and carbohydrate esterases (CEs) and play essential roles in the degradation of the cellulose/hemicellulose/pectin network in the invaded host plant. Here we applied transcriptomic and degenerate PCR approaches to identify the PCWDEs from a destructive pest of palm trees, Rhynchophorus ferrugineus, followed by a gut-specific and stage-specific differential expression analysis. We identified a total of 27 transcripts encoding GH family members and three transcripts of the CE family with cellulase, hemicellulase and pectinase activities. We also identified two GH9 candidates, which have not previously been reported from Curculionidae. The gut-specific quantitative expression analysis identified key cellulases, hemicellulases and pectinases from R. ferrugineus. The expression analysis revealed a pectin methylesterase, RferCE8u02, and a cellulase, GH45c34485, which showed the highest gut enriched expression. Comparison of PCWDE expression patterns revealed that cellulases and pectinases are significantly upregulated in the adult stages, and we observed specific high expression of the hemicellulase RferGH16c4170. Overall, our study revealed the potential of PCWDEs from R. ferrugineus, which may be useful in biotechnological applications and may represent new tools in R. ferrugineus pest management strategies. © 2017 The Royal Entomological Society.

  5. Sonocatalytical degradation enhancement for ibuprofen and sulfamethoxazole in the presence of glass beads and single-walled carbon nanotubes.

    PubMed

    Al-Hamadani, Yasir A J; Chu, Kyoung Hoon; Flora, Joseph R V; Kim, Do-Hyung; Jang, Min; Sohn, Jinsik; Joo, Wanho; Yoon, Yeomin

    2016-09-01

    Sonocatalytic degradation experiments were carried out to determine the effects of glass beads (GBs) and single-walled carbon nanotubes (SWNTs) on ibuprofen (IBP) and sulfamethoxazole (SMX) removal using low and high ultrasonic frequencies (28 and 1000kHz). In the absence of catalysts, the sonochemical degradation at pH 7, optimum power of 0.18WmL(-1), and a temperature of 15°C was higher (79% and 72%) at 1000kHz than at 28kHz (45% and 33%) for IBP and SMX, respectively. At the low frequency (28kHz) H2O2 production increased significantly, from 10μM (no GBs) to 86μM in the presence of GBs (0.1mm, 10gL(-1)); however, no enhancement was achieved at 1000kHz. In contrast, the H2O2 production increased from 10μM (no SWNTs) to 31μM at 28kHz and from 82μM (no SWNTs) to 111μM at 1000kHz in the presence of SWNTs (45mgL(-1)). Thus, maximum removals of IBP and SMX were obtained in the presence of a combination of GBs and SWNTs at the low frequency (94% and 88%) for 60min contact time; however, >99% and 97% removals were achieved for 40 and 60min contact times at the high frequency for IBP and SMX, respectively. The results indicate that both IBP and SMX degradation followed pseudo-first-order kinetics. Additionally, the enhanced removal of IBP and SMX in the presence of catalysts was because GBs and SWNTs increased the number of free OH radicals due to ultrasonic irradiation and the adsorption capacity increase with SWNT dispersion.

  6. Diversity and strain specificity of plant cell wall degrading enzymes revealed by the draft genome of Ruminococcus flavefaciens FD-1.

    PubMed

    Berg Miller, Margret E; Antonopoulos, Dionysios A; Rincon, Marco T; Band, Mark; Bari, Albert; Akraiko, Tatsiana; Hernandez, Alvaro; Thimmapuram, Jyothi; Henrissat, Bernard; Coutinho, Pedro M; Borovok, Ilya; Jindou, Sadanari; Lamed, Raphael; Flint, Harry J; Bayer, Edward A; White, Bryan A

    2009-08-14

    Ruminococcus flavefaciens is a predominant cellulolytic rumen bacterium, which forms a multi-enzyme cellulosome complex that could play an integral role in the ability of this bacterium to degrade plant cell wall polysaccharides. Identifying the major enzyme types involved in plant cell wall degradation is essential for gaining a better understanding of the cellulolytic capabilities of this organism as well as highlighting potential enzymes for application in improvement of livestock nutrition and for conversion of cellulosic biomass to liquid fuels. The R. flavefaciens FD-1 genome was sequenced to 29x-coverage, based on pulsed-field gel electrophoresis estimates (4.4 Mb), and assembled into 119 contigs providing 4,576,399 bp of unique sequence. As much as 87.1% of the genome encodes ORFs, tRNA, rRNAs, or repeats. The GC content was calculated at 45%. A total of 4,339 ORFs was detected with an average gene length of 918 bp. The cellulosome model for R. flavefaciens was further refined by sequence analysis, with at least 225 dockerin-containing ORFs, including previously characterized cohesin-containing scaffoldin molecules. These dockerin-containing ORFs encode a variety of catalytic modules including glycoside hydrolases (GHs), polysaccharide lyases, and carbohydrate esterases. Additionally, 56 ORFs encode proteins that contain carbohydrate-binding modules (CBMs). Functional microarray analysis of the genome revealed that 56 of the cellulosome-associated ORFs were up-regulated, 14 were down-regulated, 135 were unaffected, when R. flavefaciens FD-1 was grown on cellulose versus cellobiose. Three multi-modular xylanases (ORF01222, ORF03896, and ORF01315) exhibited the highest levels of up-regulation. The genomic evidence indicates that R. flavefaciens FD-1 has the largest known number of fiber-degrading enzymes likely to be arranged in a cellulosome architecture. Functional analysis of the genome has revealed that the growth substrate drives expression of enzymes

  7. Diversity and Strain Specificity of Plant Cell Wall Degrading Enzymes Revealed by the Draft Genome of Ruminococcus flavefaciens FD-1

    PubMed Central

    Berg Miller, Margret E.; Antonopoulos, Dionysios A.; Rincon, Marco T.; Band, Mark; Bari, Albert; Akraiko, Tatsiana; Hernandez, Alvaro; Thimmapuram, Jyothi; Henrissat, Bernard; Coutinho, Pedro M.; Borovok, Ilya; Jindou, Sadanari; Lamed, Raphael; Flint, Harry J.; Bayer, Edward A.; White, Bryan A.

    2009-01-01

    Background Ruminococcus flavefaciens is a predominant cellulolytic rumen bacterium, which forms a multi-enzyme cellulosome complex that could play an integral role in the ability of this bacterium to degrade plant cell wall polysaccharides. Identifying the major enzyme types involved in plant cell wall degradation is essential for gaining a better understanding of the cellulolytic capabilities of this organism as well as highlighting potential enzymes for application in improvement of livestock nutrition and for conversion of cellulosic biomass to liquid fuels. Methodology/Principal Findings The R. flavefaciens FD-1 genome was sequenced to 29x-coverage, based on pulsed-field gel electrophoresis estimates (4.4 Mb), and assembled into 119 contigs providing 4,576,399 bp of unique sequence. As much as 87.1% of the genome encodes ORFs, tRNA, rRNAs, or repeats. The GC content was calculated at 45%. A total of 4,339 ORFs was detected with an average gene length of 918 bp. The cellulosome model for R. flavefaciens was further refined by sequence analysis, with at least 225 dockerin-containing ORFs, including previously characterized cohesin-containing scaffoldin molecules. These dockerin-containing ORFs encode a variety of catalytic modules including glycoside hydrolases (GHs), polysaccharide lyases, and carbohydrate esterases. Additionally, 56 ORFs encode proteins that contain carbohydrate-binding modules (CBMs). Functional microarray analysis of the genome revealed that 56 of the cellulosome-associated ORFs were up-regulated, 14 were down-regulated, 135 were unaffected, when R. flavefaciens FD-1 was grown on cellulose versus cellobiose. Three multi-modular xylanases (ORF01222, ORF03896, and ORF01315) exhibited the highest levels of up-regulation. Conclusions/Significance The genomic evidence indicates that R. flavefaciens FD-1 has the largest known number of fiber-degrading enzymes likely to be arranged in a cellulosome architecture. Functional analysis of the genome has

  8. Genomic characterization of plant cell wall degrading enzymes and in silico analysis of xylanses and polygalacturonases of Fusarium virguliforme.

    PubMed

    Chang, Hao-Xun; Yendrek, Craig R; Caetano-Anolles, Gustavo; Hartman, Glen L

    2016-07-12

    Plant cell wall degrading enzymes (PCWDEs) are a subset of carbohydrate-active enzymes (CAZy) produced by plant pathogens to degrade plant cell walls. To counteract PCWDEs, plants release PCWDEs inhibitor proteins (PIPs) to reduce their impact. Several transgenic plants expressing exogenous PIPs that interact with fungal glycoside hydrolase (GH)11-type xylanases or GH28-type polygalacturonase (PG) have been shown to enhance disease resistance. However, many plant pathogenic Fusarium species were reported to escape PIPs inhibition. Fusarium virguliforme is a soilborne pathogen that causes soybean sudden death syndrome (SDS). Although the genome of F. virguliforme was sequenced, there were limited studies focused on the PCWDEs of F. virguliforme. Our goal was to understand the genomic CAZy structure of F. viguliforme, and determine if exogenous PIPs could be theoretically used in soybean to enhance resistance against F. virguliforme. F. virguliforme produces diverse CAZy to degrade cellulose and pectin, similar to other necrotorphic and hemibiotrophic plant pathogenic fungi. However, some common CAZy of plant pathogenic fungi that catalyze hemicellulose, such as GH29, GH30, GH44, GH54, GH62, and GH67, were deficient in F. virguliforme. While the absence of these CAZy families might be complemented by other hemicellulases, F. virguliforme contained unique families including GH131, polysaccharide lyase (PL) 9, PL20, and PL22 that were not reported in other plant pathogenic fungi or oomycetes. Sequence analysis revealed two GH11 xylanases of F. virguliforme, FvXyn11A and FvXyn11B, have conserved residues that allow xylanase inhibitor protein I (XIP-I) binding. Structural modeling suggested that FvXyn11A and FvXyn11B could be blocked by XIP-I that serves as good candidate for developing transgenic soybeans. In contrast, one GH28 PG, FvPG2, contains an amino acid substitution that is potentially incompatible with the bean polygalacturonase-inhibitor protein II (PvPGIP2

  9. Leaf-cutting ant fungi produce cell wall degrading pectinase complexes reminiscent of phytopathogenic fungi

    PubMed Central

    2010-01-01

    Background Leaf-cutting (attine) ants use their own fecal material to manure fungus gardens, which consist of leaf material overgrown by hyphal threads of the basidiomycete fungus Leucocoprinus gongylophorus that lives in symbiosis with the ants. Previous studies have suggested that the fecal droplets contain proteins that are produced by the fungal symbiont to pass unharmed through the digestive system of the ants, so they can enhance new fungus garden growth. Results We tested this hypothesis by using proteomics methods to determine the gene sequences of fecal proteins in Acromyrmex echinatior leaf-cutting ants. Seven (21%) of the 33 identified proteins were pectinolytic enzymes that originated from the fungal symbiont and which were still active in the fecal droplets produced by the ants. We show that these enzymes are found in the fecal material only when the ants had access to fungus garden food, and we used quantitative polymerase chain reaction analysis to show that the expression of six of these enzyme genes was substantially upregulated in the fungal gongylidia. These unique structures serve as food for the ants and are produced only by the evolutionarily advanced garden symbionts of higher attine ants, but not by the fungi reared by the basal lineages of this ant clade. Conclusions Pectinolytic enzymes produced in the gongylidia of the fungal symbiont are ingested but not digested by Acromyrmex leaf-cutting ants so that they end up in the fecal fluid and become mixed with new garden substrate. Substantial quantities of pectinolytic enzymes are typically found in pathogenic fungi that attack live plant tissue, where they are known to breach the cell walls to allow the fungal mycelium access to the cell contents. As the leaf-cutting ant symbionts are derived from fungal clades that decompose dead plant material, our results suggest that their pectinolytic enzymes represent secondarily evolved adaptations that are convergent to those normally found in

  10. Leaf-cutting ant fungi produce cell wall degrading pectinase complexes reminiscent of phytopathogenic fungi.

    PubMed

    Schiøtt, Morten; Rogowska-Wrzesinska, Adelina; Roepstorff, Peter; Boomsma, Jacobus J

    2010-12-31

    Leaf-cutting (attine) ants use their own fecal material to manure fungus gardens, which consist of leaf material overgrown by hyphal threads of the basidiomycete fungus Leucocoprinus gongylophorus that lives in symbiosis with the ants. Previous studies have suggested that the fecal droplets contain proteins that are produced by the fungal symbiont to pass unharmed through the digestive system of the ants, so they can enhance new fungus garden growth. We tested this hypothesis by using proteomics methods to determine the gene sequences of fecal proteins in Acromyrmex echinatior leaf-cutting ants. Seven (21%) of the 33 identified proteins were pectinolytic enzymes that originated from the fungal symbiont and which were still active in the fecal droplets produced by the ants. We show that these enzymes are found in the fecal material only when the ants had access to fungus garden food, and we used quantitative polymerase chain reaction analysis to show that the expression of six of these enzyme genes was substantially upregulated in the fungal gongylidia. These unique structures serve as food for the ants and are produced only by the evolutionarily advanced garden symbionts of higher attine ants, but not by the fungi reared by the basal lineages of this ant clade. Pectinolytic enzymes produced in the gongylidia of the fungal symbiont are ingested but not digested by Acromyrmex leaf-cutting ants so that they end up in the fecal fluid and become mixed with new garden substrate. Substantial quantities of pectinolytic enzymes are typically found in pathogenic fungi that attack live plant tissue, where they are known to breach the cell walls to allow the fungal mycelium access to the cell contents. As the leaf-cutting ant symbionts are derived from fungal clades that decompose dead plant material, our results suggest that their pectinolytic enzymes represent secondarily evolved adaptations that are convergent to those normally found in phytopathogens.

  11. Pressure Sensitive Paints

    NASA Technical Reports Server (NTRS)

    Liu, Tianshu; Bencic, T.; Sullivan, J. P.

    1999-01-01

    This article reviews new advances and applications of pressure sensitive paints in aerodynamic testing. Emphasis is placed on important technical aspects of pressure sensitive paint including instrumentation, data processing, and uncertainty analysis.

  12. Paint and Pregnancy

    MedlinePlus

    ... paint can happen by: 1) Inhalation (breathing in dust and vapors/fumes). Painters with a lot of ... eye irritation. 3) Ingestion (swallowing paint chips and dust). Does the level of exposure (high versus low) ...

  13. Suppressive effects of dietary EPA-rich fish oil on the degradation of elastin fibers in the aortic wall in nicotine-administered mice.

    PubMed

    Kugo, Hirona; Zaima, Nobuhiro; Onozato, Megumi; Miyamoto, Chie; Hashimoto, Keisuke; Yanagimoto, Kenichi; Moriyama, Tatsuya

    2017-08-01

    Abdominal aortic aneurysm (AAA) is a vascular disease involving gradual dilation of the abdominal aorta. Recent studies suggest that nicotine, which is a primary component in cigarette smoke, is closely associated with the development and rupture of an AAA. Nicotine accelerates AAA development through the weakening of the vascular wall by increasing oxidative stress and matrix metalloproteinase (MMP)-2 expression. However, little is known about preventing the AAA induced by nicotine. A non-surgical means of preventing the weakening of the vascular wall before the onset of AAA by functional food factors would be a valuable option over surgery. Fish oil is a functional food that is rich in n-3 polyunsaturated fatty acids that have an anti-inflammatory effect. In this study, we evaluated the effect of dietary fish oil on the weakening of the aortic wall due to nicotine administration in a mouse model. Histological analysis showed that the dietary fish oil suppressed the degradation of elastin fibers in the nicotine-administered mice. Additionally, the dietary fish oil suppressed the protein level of MMP-12, macrophage infiltration, and the oxidative stress in the vascular wall. These results suggest that fish oil could suppress the weakening of the vascular wall by suppressing the elastin fiber degradation caused by nicotine. By suppressing the nicotine induced weakening of the vascular wall, fish oil might help prevent the development of AAA.

  14. 77 FR 76996 - Lead; Renovation, Repair, and Painting Program for Public and Commercial Buildings; Request for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-31

    ..., drywall and insulation contractors, painting and wall covering contractors, finish carpentry contractors...; finish carpentry contractors; drywall and insulation contractors; siding contractors; tile and terrazzo...

  15. 78 FR 27906 - Lead; Renovation, Repair, and Painting Program for Public and Commercial Buildings; Notice of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-13

    ... contractors, drywall and insulation contractors, painting and wall covering contractors, finish carpentry... contractors; finish carpentry contractors; drywall and insulation contractors; siding contractors; tile and...

  16. I Can Paint!

    ERIC Educational Resources Information Center

    Hart, Kate; Bower, Robin, Ed.

    This book gives detailed information concerning the use of tools and media of paint. It aims at developing skills and knowledge that will allow young students to express themselves by painting. The book is organized into five sections with subheadings, including: (1) "Introduction"; (2) "Exploring Paint As We Use..." with…

  17. Paints and Preservatives.

    ERIC Educational Resources Information Center

    Powell, Larry E.; Miller, Larry E.

    The publication contains an outline for use by agriculture teachers in developing a teaching plan for a unit on paints and preservatives. The topics included are (1) recognizing, solving, and preventing paint problems and (2) operating and using power spray painting equipment. Items presented for each topic are: the situation, (intended to inform…

  18. Identification and characterization of plant cell wall degrading enzymes from three glycoside hydrolase families in the cerambycid beetle Apriona japonica.

    PubMed

    Pauchet, Yannick; Kirsch, Roy; Giraud, Sandra; Vogel, Heiko; Heckel, David G

    2014-06-01

    Xylophagous insects have evolved to thrive in a highly challenging environment. For example, wood-boring beetles from the family Cerambycidae feed exclusively on woody tissues, and to efficiently access the nutrients present in this sub-optimal environment, they have to cope with the lignocellulose barrier. Whereas microbes of the insect's gut flora were hypothesized to be responsible for the degradation of lignin, the beetle itself depends heavily on the secretion of a range of enzymes, known as plant cell wall degrading enzymes (PCWDEs), to efficiently digest both hemicellulose and cellulose networks. Here we sequenced the larval gut transcriptome of the Mulberry longhorn beetle, Apriona japonica (Cerambycidae, Lamiinae), in order to investigate the arsenal of putative PCWDEs secreted by this species. We combined our transcriptome with all available sequencing data derived from other cerambycid beetles in order to analyze and get insight into the evolutionary history of the corresponding gene families. Finally, we heterologously expressed and functionally characterized the A. japonica PCWDEs we identified from the transcriptome. Together with a range of endo-β-1,4-glucanases, we describe here for the first time the presence in a species of Cerambycidae of (i) a xylanase member of the subfamily 2 of glycoside hydrolase family 5 (GH5 subfamily 2), as well as (ii) an exopolygalacturonase from family GH28. Our analyses greatly contribute to a better understanding of the digestion physiology of this important group of insects, many of which are major pests of forestry worldwide. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. 178. PAINT SHOP, LOOKING SOUTHWEST TOWARD CENTER OF ROOM. OPENING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    178. PAINT SHOP, LOOKING SOUTHWEST TOWARD CENTER OF ROOM. OPENING IN BACKGROUND IS SLIDING WALL. - Gruber Wagon Works, Pennsylvania Route 183 & State Hill Road at Red Bridge Park, Bernville, Berks County, PA

  20. Production of cell wall-degrading enzymes by Aspergillus nidulans: a model system for fungal pathogenesis of plants.

    PubMed Central

    Dean, R A; Timberlake, W E

    1989-01-01

    The cell wall-degrading enzymes polygalacturonase and pectate lyase have been suggested to be crucial for penetration and colonization of plant tissues by some fungal pathogens. We have found that Aspergillus nidulans (= Emericella nidulans), a saprophytic Ascomycete, produces levels of these enzymes equal to those produced by soft-rotting Erwinia species. Induction of polygacturonase and pectate lyase in A. nidulans requires substrate and is completely repressed by glucose. Surprisingly, inoculation of excised plant tissues with A. nidulans conidia leads to formation of necrotic, water-soaked lesions within which the organism sporulates. Thus, A. nidulans has phytopathogenic potential. The release of glucose and other sugars from wounded tissues may repress pectolytic enzyme production and limit disease development. Therefore, we tested creA204, a mutation that relieves glucose repression of some A. nidulans carbon utilization enzymes, for its effect on production of pectolytic enzymes. creA204 failed to relieve catabolite repression of polygalacturonase or pectate lyase and had no effect on disease severity. PMID:2535501

  1. CHARACTERIZATION OF EMISSIONS OF VOLATILE ORGANIC COMPOUNDS FROM INTERIOR ALKYD PAINT

    EPA Science Inventory

    Alkyd paint continues to be used indoors for application to wood trim, cabinet surfaces, and some kitchen and bathroom walls. Paint may represent a significant source of volatile organic compounds (VOCs) indoors depending on the frequency of use and amount of surface paint. The U...

  2. CHARACTERIZATION OF EMISSIONS OF VOLATILE ORGANIC COMPOUNDS FROM INTERIOR ALKYD PAINT

    EPA Science Inventory

    Alkyd paint continues to be used indoors for application to wood trim, cabinet surfaces, and some kitchen and bathroom walls. Paint may represent a significant source of volatile organic compounds (VOCs) indoors depending on the frequency of use and amount of surface paint. The U...

  3. The actinobacterial colonization of Etruscan paintings.

    PubMed

    Diaz-Herraiz, Marta; Jurado, Valme; Cuezva, Soledad; Laiz, Leonila; Pallecchi, Pasquino; Tiano, Piero; Sanchez-Moral, Sergio; Saiz-Jimenez, Cesareo

    2013-01-01

    The paintings from Tomba della Scimmia, in Tuscany, are representative of the heavy bacterial colonization experienced in most Etruscan necropolises. The tomb remained open until the late 70's when it was closed because of severe deterioration of the walls, ceiling and paintings after decades of visits. The deterioration is the result of environmental changes and impacts suffered since its discovery in 1846. We show scanning electron microscopy and molecular studies that reveal the extent and nature of the biodeterioration. Actinobacteria, mainly Nocardia and Pseudonocardia colonize and grow on the tomb walls and this process is linked to the availability of organic matter, phyllosilicates (e.g. clay minerals) and iron oxides. Nocardia is found metabolically active in the paintings. The data confirm the specialization of the genera Nocardia and Pseudonocardia in the colonization of subterranean niches.

  4. The Actinobacterial Colonization of Etruscan Paintings

    PubMed Central

    Diaz-Herraiz, Marta; Jurado, Valme; Cuezva, Soledad; Laiz, Leonila; Pallecchi, Pasquino; Tiano, Piero; Sanchez-Moral, Sergio; Saiz-Jimenez, Cesareo

    2013-01-01

    The paintings from Tomba della Scimmia, in Tuscany, are representative of the heavy bacterial colonization experienced in most Etruscan necropolises. The tomb remained open until the late 70′s when it was closed because of severe deterioration of the walls, ceiling and paintings after decades of visits. The deterioration is the result of environmental changes and impacts suffered since its discovery in 1846. We show scanning electron microscopy and molecular studies that reveal the extent and nature of the biodeterioration. Actinobacteria, mainly Nocardia and Pseudonocardia colonize and grow on the tomb walls and this process is linked to the availability of organic matter, phyllosilicates (e.g. clay minerals) and iron oxides. Nocardia is found metabolically active in the paintings. The data confirm the specialization of the genera Nocardia and Pseudonocardia in the colonization of subterranean niches. PMID:23486535

  5. Suppression of Cell Wall Degrading Enzymes and their Encoding Genes in Button Mushrooms (Agaricus bisporus) by CaCl2 and Citric Acid.

    PubMed

    Khan, Zia Ullah; Jiayin, Li; Khan, Nasir Mehmood; Mou, Wangshu; Li, Dongdong; Wang, Yansheng; Feng, Simin; Luo, Zisheng; Mao, Linchun; Ying, Tiejin

    2017-03-01

    Fresh button mushrooms (Agaricus bisporus) were harvested and treated with a solution of 1.5% CaCl2 + 0.5% citric acid and stored for 16 days at 12 °C. The effects of this treatment on firmness, weight, color, cell wall compositions (cellulose and chitin) and cell wall degrading enzymes (cel1ulase, beta-1, 3 glucanase, chitinase and phenylalanine ammonialyase) were investigated during post-harvest storage. The expressions of major genes (Cel1, Glu1, Chi1 and PAL1) involved in cell wall degradation during post-harvest storage were also monitored. The results revealed that the post-harvest chemical treatment maintained better firmness, weight, color and inhibited cellulase, beta-1, 3 glucanase, chitinase and phenylalanine ammonialyase activities. These findings showed that the down-regulation of cell wall degrading enzymes is a possible mechanism that delays the softening of button mushrooms by the application of combined chemical treatment.

  6. Cell wall-degrading enzymes of Didymella bryoniae in relation to fungal growth and virulence in cantaloupe fruit

    PubMed Central

    Zhang, J.; Bruton, B. D.; Biles, C. L.

    2014-01-01

    Didymella bryoniae is an important pathogen of cucurbits worldwide. Virulence factors of D. bryoniae were investigated in regard to fungal growth and the production of cell wall-degrading enzymes, polygalacturonase (PG), pectate lyase (PL), pectin lyase (PNL), β-galactosidase (β-Gal) and cellulase (Cx). Virulence levels of five D. bryoniae isolates were determined by the severity of inoculated cantaloupe fruit decay. The highly virulent isolates had more mycelial growth than the moderately virulent isolates in different media. PG activities produced by the highly virulent isolates in shake cultures and in decayed fruit were greater than those of the moderately virulent isolates. PNL, but not PL, in decayed fruit was higher with the highly virulent isolates compared to the moderately virulent ones. The highly virulent isolates showed higher Cx activity than the moderately virulent ones in decayed fruit and in fruit tissue shake culture. β-Gal activities of the highly virulent isolates in pectin shake culture and in decayed fruit were greater than those of the two moderately virulent isolates although fruit also produced β-Gal. Protein analysis showed two fungal β-Gal isozymes in decayed fruit compared to those of healthy fruit. Correlation analysis indicated that the activities of PG, PNL, β-Gal and Cx in cultures and in decayed fruit positively correlated with fungal growth and fruit decay severity. The results of this study suggest that PG, PNL, β-Gal, and Cx appear to be virulence factors of D. bryoniae in cantaloupe decay with PG and β-Gal as the most predominant fruit decay enzymes. PMID:25364138

  7. Regulation of three genes encoding cell-wall-degrading enzymes of Trichoderma aggressivum during interaction with Agaricus bisporus.

    PubMed

    Abubaker, Kamal S; Sjaarda, Calvin; Castle, Alan J

    2013-06-01

    Members of the genus Trichoderma are very effective competitors of a variety of fungi. Cell-wall-degrading enzymes, including proteinases, glucanases, and chitinases, are commonly secreted as part of the competitive process. Trichoderma aggressivum is the causative agent of green mould disease of the button mushroom, Agaricus bisporus. The structures of 3 T. aggressivum genes, prb1 encoding a proteinase, ech42 encoding an endochitinase, and a β-glucanase gene, were determined. Promoter elements in the prb1 and ech42 genes suggested that transcription is regulated by carbon and nitrogen levels and by stress. Both genes had mycoparasitism-related elements indicating potential roles for the protein products in competition. The promoter of the β-glucanase gene contained CreA and AreA binding sites indicative of catabolite regulation but contained no mycoparasitism elements. Transcription of the 3 genes was measured in mixed cultures of T. aggressivum and A. bisporus. Two A. bisporus strains, U1, which is sensitive to green mould disease, and SB65, which shows some resistance, were used in co-cultivation tests to assess possible roles of the genes in disease production and severity. prb1 and ech42 were coordinately upregulated after 5 days, whereas β-glucanase transcription was upregulated from day 0 with both Agaricus strains. Upregulation was much less pronounced in mixed cultures of T. aggressivum with the resistant strain, SB65, than with the sensitive strain, U1. These observations suggested that the proteins encoded by these genes have roles in both nutrition and in severity of green mould disease.

  8. Effects of cell wall deficiency on the synthesis of polysaccharide-degrading exoenzymes: a study on mycelial and wall-less phenotypes of the fz; sg; os-1 ('slime') triple mutant of Neurospora crassa.

    PubMed

    Polizeli, M L; Pietro, R C; Jorge, J A; Terenzi, H F

    1990-08-01

    The production of exoenzymes which degrade cellulose, polygalacturonic acid and xylan was studied in mycelial and wall-less phenotypic derivatives of Neurospora crassa obtained by vegetative selection applied to a single fz;sg;os-1 ('slime'-like) segregant (strain RCP-3) of a cross 'slime' x wild type. The unrelated stable 'slime' strain FGSC 1118 was also studied. The synthesis of polysaccharide-degrading enzymes was normally induced by polysaccharidic substrates and was sensitive to carbon-catabolite repression for both mycelium-forming phenotypes (mycelial intermediate and spheroplast-hyphal intermediate) of strain RCP-3. The stable 'slime' from RCP-3 produced cellulose-degrading activity and xylan-degrading activity constitutively but was fully sensitive to glucose repression. The stable 'slime' RCP-3 did not synthesize polygalacturonic-acid-degrading activity, even in the presence of inducers. For the stable 'slime' FGSC 1118, all of the polysaccharide-degrading activities were produced constitutively and were markedly resistant to glucose repression. The possible epigenetic origin of the different properties of stable 'slimes' RCP-3 and FGSC 1118 is considered. These results may relate to the role of the cell surface in the processing of regulatory signals which control the adaptation of the fungal cell to the nutritional environment.

  9. BnMs3 is required for tapetal differentiation and degradation, microspore separation, and pollen-wall biosynthesis in Brassica napus

    PubMed Central

    Zhou, Zhengfu; Dun, Xiaoling; Xia, Shengqian; Shi, Dianyi; Qin, Maomao; Yi, Bin; Wen, Jing; Shen, Jinxiong; Ma, Chaozhi; Tu, Jinxing; Fu, Tingdong

    2012-01-01

    7365AB, a recessive genetic male sterility system, is controlled by BnMs3 in Brassica napus, which encodes a Tic40 protein required for tapetum development. However, the role of BnMs3 in rapeseed anther development is still largely unclear. In this research, cytological analysis revealed that anther development of a Bnms3 mutant has defects in the transition of the tapetum to the secretory type, callose degradation, and pollen-wall formation. A total of 76 down-regulated unigenes in the Bnms3 mutant, several of which are associated with tapetum development, callose degeneration, and pollen development, were isolated by suppression subtractive hybridization combined with a macroarray analysis. Reverse genetics was applied by means of Arabidopsis insertional mutant lines to characterize the function of these unigenes and revealed that MSR02 is only required for transport of sporopollenin precursors through the plasma membrane of the tapetum. The real-time PCR data have further verified that BnMs3 plays a primary role in tapetal differentiation by affecting the expression of a few key transcription factors, participates in tapetal degradation by modulating the expression of cysteine protease genes, and influences microspore separation by manipulating the expression of BnA6 and BnMSR66 related to callose degradation and of BnQRT1 and BnQRT3 required for the primary cell-wall degradation of the pollen mother cell. Moreover, BnMs3 takes part in pollen-wall formation by affecting the expression of a series of genes involved in biosynthesis and transport of sporopollenin precursors. All of the above results suggest that BnMs3 participates in tapetum development, microspore release, and pollen-wall formation in B. napus. PMID:22174440

  10. Changes in Cell Wall Polymers and Degradability in Maize Mutants Lacking 3'- and 5'-O-Methyltransferases Involved in Lignin Biosynthesis.

    PubMed

    Fornalé, Silvia; Rencoret, Jorge; García-Calvo, Laura; Encina, Antonio; Rigau, Joan; Gutiérrez, Ana; Del Río, José Carlos; Caparros-Ruiz, David

    2017-02-01

    Caffeoyl coenzyme A 3-O-methyltransferase (CCoAOMT) and caffeic acid-O-methyltransferase (COMT) are key enzymes in the biosynthesis of coniferyl and sinapyl alcohols, the precursors of guaiacyl (G) and syringyl (S) lignin subunits. The function of these enzymes was characterized in single and double mutant maize plants. In this work, we determined that the comt (brown-midrib 3) mutant plants display a reduction of the flavonolignin unit derived from tricin (a dimethylated flavone), demonstrating that COMT is a key enzyme involved in the synthesis of this compound. In contrast, the ccoaomt1 mutants display a wild-type amount of tricin, suggesting that CCoAOMT1 is not essential for the synthesis of this compound. Based on our data, we suggest that CCoAOMT1 is involved in lignin biosynthesis at least in midribs. The phenotype of ccoaomt1 mutant plants displays no alterations, and their lignin content and composition remain unchanged. On the other hand, the ccoaomt1 comt mutant displays phenotypic and lignin alterations similar to those already described for the comt mutant. Although stems from the three mutants display a similar increase of hemicelluloses, the effect on cell wall degradability varies, the cell walls of ccoaomt1 being the most degradable. This suggests that the positive effect of lignin reduction on cell wall degradability of comt and ccoaomt1 comt mutants is counteracted by changes occurring in lignin composition, such as the decreased S/G ratio. In addition, the role of the flavonolignin unit derived from tricin in cell wall degradability is also discussed.

  11. In vitro growth and cell wall degrading enzyme production by Argentinean isolates of Macrophomina phaseolina, the causative agent of charcoal rot in corn.

    PubMed

    Ramos, Araceli M; Gally, Marcela; Szapiro, Gala; Itzcovich, Tatiana; Carabajal, Maira; Levin, Laura

    Macrophomina phaseolina is a polyphagous phytopathogen, causing stalk rot on many commercially important species. Damages caused by this pathogen in soybean and maize crops in Argentina during drought and hot weather have increased due its ability to survive as sclerotia in soil and crop debris under non-till practices. In this work, we explored the in vitro production of plant cell wall-degrading enzymes [pectinases (polygalacturonase and polymethylgalacturonase); cellulases (endoglucanase); hemicellulases (endoxylanase) and the ligninolytic enzyme laccase] by several Argentinean isolates of M. phaseolina, and assessed the pathogenicity of these isolates as a preliminary step to establish the role of these enzymes in M. phaseolina-maize interaction. The isolates were grown in liquid synthetic medium supplemented with glucose, pectin, carboxymethylcellulose or xylan as carbon sources and/or enzyme inducers and glutamic acid as nitrogen source. Pectinases were the first cell wall-degrading enzymes detected and the activities obtained (polygalacturonase activity was between 0.4 and 1.3U/ml and polymethylgalacturonase between 0.15 and 1.3U/ml) were higher than those of cellulases and xylanases, which appeared later and in a lesser magnitude. This sequence would promote initial tissue maceration followed by cell wall degradation. Laccase was detected in all the isolates evaluated (activity was between 36U/l and 63U/l). The aggressiveness of the isolates was tested in maize, sunflower and watermelon seeds, being high on all the plants assayed. This study reports for the first time the potential of different isolates of M. phaseolina to produce plant cell wall-degrading enzymes in submerged fermentation. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  12. Novel environmental species isolated from the plaster wall surface of mural paintings in the Takamatsuzuka tumulus: Bordetella muralis sp. nov., Bordetella tumulicola sp. nov. and Bordetella tumbae sp. nov.

    PubMed

    Tazato, Nozomi; Handa, Yutaka; Nishijima, Miyuki; Kigawa, Rika; Sano, Chie; Sugiyama, Junta

    2015-12-01

    Ten strains of Gram-stain-negative, non-spore-forming, non-motile coccobacilli were isolated from the plaster wall surface of 1300-year-old mural paintings inside the stone chamber of the Takamatsuzuka tumulus in Asuka village (Asuka-mura), Nara Prefecture, Japan. Based on 16S rRNA gene sequence analysis of the isolates, they belonged to the proteobacterial genus Bordetella (class Betaproteobacteria) and could be separated into three groups representing novel lineages within the genus Bordetella. Three isolates were selected, one from each group, and identified carefully using a polyphasic approach. The isolates were characterized by the presence of Q-8 as their major ubiquinone system and C16 : 0 (30.0-41.8 %), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c; 10.1-27.0 %) and C17 : 0 cyclo (10.8-23.8 %) as the predominant fatty acids. The major hydroxy fatty acids were C12 : 0 2-OH and C14 : 0 2-OH. The DNA G+C content was 59.6-60.0 mol%. DNA-DNA hybridization tests confirmed that the isolates represented three separate novel species, for which the names Bordetella muralis sp. nov. (type strain T6220-3-2bT = JCM 30931T = NCIMB 15006T), Bordetella tumulicola sp. nov. (type strain T6517-1-4bT = JCM 30935T = NCIMB 15007T) and Bordetella tumbae sp. nov. (type strain T6713-1-3bT = JCM 30934T = NCIMB 15008T) are proposed. These results support previous evidence that members of the genus Bordetella exist in the environment and may be ubiquitous in soil and/or water.

  13. Process for non-contact removal of organic coatings from the surface of paintings

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A. (Inventor); Rutledge, Sharon K. (Inventor)

    1995-01-01

    The present invention discloses a method of removing organic protective coatings from a painting. In the present invention degraded protective coatings such as lacquers, acrylics, natural resins, carbons, soot, and polyurethane are safely removed from the surface of a painting without contact to the surface of the painting. This method can be used for restoration of paintings when they have been damaged, through age, fire, etc.

  14. Process for Non-Contact Removal of Organic Coatings from the Surface of Paintings

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A. (Inventor); Rutledge, Sharon K. (Inventor)

    1996-01-01

    The present invention discloses a method of removing organic protective coatings from a painting. In the present invention degraded protective coatings such as lacquers, acrylics, natural resins, carbons, soot, and polyurethane are safely removed from the surface of a painting without contact to the surface of the painting. This method can be used for restoration of paintings when they have been damaged, through age, fire, etc.

  15. 107. TOWER STAIRHALL, SECOND FLOOR LANDING, SOUTH WALL, ENTABLATURE SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    107. TOWER STAIRHALL, SECOND FLOOR LANDING, SOUTH WALL, ENTABLATURE SHOWING SECTION WITH ALL PAINT REMOVED RANGING FROM TWENTY-FIVE TO FIFTY COATS OF PAINT ON SECTIONS - Independence Hall Complex, Independence Hall, 500 Chestnut Street, Philadelphia, Philadelphia County, PA

  16. Control of paint overspray in autobody repair shops.

    PubMed

    Heitbrink, W A; Wallace, M E; Bryant, C J; Ruch, W E

    1995-10-01

    Commercially available controls for reducing worker exposure to paint overspray were evaluated in six autobody shops and a spray-painting equipment manufacturer's test facility. Engineering control measures included spray-painting booths, vehicle preparation stations, and spray-painting guns. The controls were evaluated by measuring particulate overspray concentrations in the worker's breathing zone, visualizing the airflow in spray-painting booths and vehicle preparation stations, and measuring airflow volumes and velocities. In addition, respirator usage observations were collected at five of the autobody repair shops, and quantitative fit tests were conducted on existing respirators at three shops. Several conclusions were drawn from this study. Downdraft spray-painting booths provide lower particulate overspray concentrations measured on the worker than crossdraft and semidowndraft spray-painting booths. In the latter two booths, the spray-painting gun can disperse as much as half the paint overspray into the incoming fresh air, increasing worker overspray exposure. Vehicle preparation stations have no walls to contain the overspray and, commonly, a single exhaust fan removes air from the painting area. Airflow patterns suggest that these do not control the paint overspray. Switching from a conventional spray-painting gun to a high-volume low pressure spray-painting gun reduced the particulate overspray concentration by a factor of 2 at a manufacturer's test facility. However, this change did not significantly affect solvent concentrations. Finally, respirator usage in five of the six shops studied was inappropriate. Respirators were poorly maintained and/or did not fit the workers, perhaps due to the absence of a formal respirator program.

  17. Interior building details of Building C, Room C113: historic painted ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior building details of Building C, Room C-113: historic painted plaster lath partition wall, painted plaster east wall and four light over two light double-hung window; southerly view - San Quentin State Prison, Building 22, Point San Quentin, San Quentin, Marin County, CA

  18. Time-Resolved Photoluminescence Spectroscopy and Imaging: New Approaches to the Analysis of Cultural Heritage and Its Degradation

    PubMed Central

    Nevin, Austin; Cesaratto, Anna; Bellei, Sara; D'Andrea, Cosimo; Toniolo, Lucia; Valentini, Gianluca; Comelli, Daniela

    2014-01-01

    Applications of time-resolved photoluminescence spectroscopy (TRPL) and fluorescence lifetime imaging (FLIM) to the analysis of cultural heritage are presented. Examples range from historic wall paintings and stone sculptures to 20th century iconic design objects. A detailed description of the instrumentation developed and employed for analysis in the laboratory or in situ is given. Both instruments rely on a pulsed laser source coupled to a gated detection system, but differ in the type of information they provide. Applications of FLIM to the analysis of model samples and for the in-situ monitoring of works of art range from the analysis of organic materials and pigments in wall paintings, the detection of trace organic substances on stone sculptures, to the mapping of luminescence in late 19th century paintings. TRPL and FLIM are employed as sensors for the detection of the degradation of design objects made in plastic. Applications and avenues for future research are suggested. PMID:24699285

  19. Jasper Johns' Painted Words.

    ERIC Educational Resources Information Center

    Levinger, Esther

    1989-01-01

    States that the painted words in Jasper Johns' art act in two different capacities: concealed words partake in the artist's interrogation of visual perception; and visible painted words question classical representation. Argues that words are Johns' means of critiquing modernism. (RS)

  20. Pollock without Paint?

    ERIC Educational Resources Information Center

    Sutley, Jane

    2011-01-01

    This article describes how the author exposes her students to the world of Jackson Pollock, the artist who brings to mind dripping, meandering, splashing puddles of paint. Pollock's action paintings of the late 1940s-'50s call out for unfettered movement, fluidity, and freedom of application. Is it even possible to capture the action, rhythm and…

  1. Paint-Stirrer Submarine

    ERIC Educational Resources Information Center

    Young, Jocelyn; Hardy, Kevin

    2007-01-01

    In this article, the authors discuss a unique and challenging laboratory exercise called, the paint-stir-stick submarine, that keeps the students enthralled. The paint-stir-stick submarine fits beautifully with the National Science Education Standards Physical Science Content Standard B, and with the California state science standards for physical…

  2. What's Behind A Painting?

    Treesearch

    John Zasada

    2001-01-01

    In art galleries, one often studies a painting from various angles and distances, seeking to discover all that is possible about the method and style of the artist and what the artist is trying to communicate. In other words the observer is trying to detremine "what is behind the painting."

  3. Pollock without Paint?

    ERIC Educational Resources Information Center

    Sutley, Jane

    2011-01-01

    This article describes how the author exposes her students to the world of Jackson Pollock, the artist who brings to mind dripping, meandering, splashing puddles of paint. Pollock's action paintings of the late 1940s-'50s call out for unfettered movement, fluidity, and freedom of application. Is it even possible to capture the action, rhythm and…

  4. Jasper Johns' Painted Words.

    ERIC Educational Resources Information Center

    Levinger, Esther

    1989-01-01

    States that the painted words in Jasper Johns' art act in two different capacities: concealed words partake in the artist's interrogation of visual perception; and visible painted words question classical representation. Argues that words are Johns' means of critiquing modernism. (RS)

  5. Paint-Stirrer Submarine

    ERIC Educational Resources Information Center

    Young, Jocelyn; Hardy, Kevin

    2007-01-01

    In this article, the authors discuss a unique and challenging laboratory exercise called, the paint-stir-stick submarine, that keeps the students enthralled. The paint-stir-stick submarine fits beautifully with the National Science Education Standards Physical Science Content Standard B, and with the California state science standards for physical…

  6. Divergent selection for ester-linked diferulates in maize pith stalk tissues: effects on cell wall composition and degradability

    USDA-ARS?s Scientific Manuscript database

    Cross-linking of grass cell wall components through diferulates (DFAs) has a marked impact on cell wall properties. However, results of genetic selection for DFA concentration have not been reported for any grass species. We report here the results of direct selection for ester-linked DFA concentrat...

  7. Analysis of mural paintings in Istria.

    PubMed

    Mazzocchin, G A; Rudello, D; Maraković, N; Marić, I

    2007-08-01

    Fragments of wall paintings from Istria, coming from the Basilica of Guran near Vodnjan, from the cemeterial Church of Saint Simeon in Guran and from the Benedictine monastery of Santa Maria Alta near Bale were studied. The analytical instrumental techniques used were Optical Microscopy, Scanning Electron Microscopy equipped with an EDS microanalysis detector, X Ray diffraction, FTIR infrared Spectroscopy and Raman Spectroscopy. Red and yellow pigments used in Guran and Bale have bean derived from red and yellow istrian bauxites, as already demonstrated for works from 11th to 15th century. The blue pigment found in the paintings of the Bale Chapel is a lapislazzuli blue; this fact confirms the literature data referring to the period from 11th to the 16th century. The materials and pigments used at Bale and Guran fit with the Istrian tradition and history of painting going back to the first Carolingian period.

  8. Forensic aspects of the weathering and ageing of spray paints.

    PubMed

    Jost, Cédric; Muehlethaler, Cyril; Massonnet, Geneviève

    2016-01-01

    This paper presents a preliminary study on the degradation of spray paint samples, illustrated by Optical, FTIR and Raman measurements. As opposed to automotive paints which are specifically designed for improved outdoor exposure and protected using hindered amine light absorbers (HALS) and ultra-violet absorbers (UVA), the spray paints on their side are much simpler in composition and very likely to suffer more from joint effects of solar radiation, temperature and humidity. Six different spray paint were exposed to outdoor UV-radiation for a total period of three months and both FTIR and Raman measurements were taken systematically during this time. These results were later compared to an artificial degradation using a climate chamber. For infrared spectroscopy, degradation curves were plotted using the photo-oxidation index (POI), and could be successfully approximated with a logarithmic fitting (R(2)>0.8). The degradation can appear after the first few days of exposure and be important until 2 months, where it stabilizes and follow a more linear trend afterwards. One advantage is that the degradation products appeared almost exclusively at the far end (∼3000cm(-1)) of mid-infrared spectra, and that the fingerprint region of the spectra remained stable over the studied period of time. Raman results suggest that the pigments on the other side, are much more stable and have not shown any sign of degradation over the time of this study. Considering the forensic implications of this environmental degradation, care should be taken when comparing samples if weathering is an option (e.g. an exposed graffiti compared to the paint from a fresh spray paint can). Degradation issues should be kept in mind as they may induce significant differences between paint samples of common origin.

  9. Cell Wall-Degrading Enzymes Enlarge the Pore Size of Intervessel Pit Membranes in Healthy and Xylella fastidiosa-Infected Grapevines1[C][W][OA

    PubMed Central

    Pérez-Donoso, Alonso G.; Sun, Qiang; Roper, M. Caroline; Greve, L. Carl; Kirkpatrick, Bruce; Labavitch, John M.

    2010-01-01

    The pit membrane (PM) is a primary cell wall barrier that separates adjacent xylem water conduits, limiting the spread of xylem-localized pathogens and air embolisms from one conduit to the next. This paper provides a characterization of the size of the pores in the PMs of grapevine (Vitis vinifera). The PM porosity (PMP) of stems infected with the bacterium Xylella fastidiosa was compared with the PMP of healthy stems. Stems were infused with pressurized water and flow rates were determined; gold particles of known size were introduced with the water to assist in determining the size of PM pores. The effect of introducing trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid (CDTA), oligogalacturonides, and polygalacturonic acid into stems on water flux via the xylem was also measured. The possibility that cell wall-degrading enzymes could alter the pore sizes, thus facilitating the ability of X. fastidiosa to cross the PMs, was tested. Two cell wall-degrading enzymes likely to be produced by X. fastidiosa (polygalactuoronase and endo-1,4- β -glucanase) were infused into stems, and particle passage tests were performed to check for changes in PMP. Scanning electron microscopy of control and enzyme-infused stem segments revealed that the combination of enzymes opened holes in PMs, probably explaining enzyme impacts on PMP and how a small X. fastidiosa population, introduced into grapevines by insect vectors, can multiply and spread throughout the vine and cause Pierce's disease. PMID:20107028

  10. Production by Tobacco Transplastomic Plants of Recombinant Fungal and Bacterial Cell-Wall Degrading Enzymes to Be Used for Cellulosic Biomass Saccharification

    PubMed Central

    Leelavathi, Sadhu; Doria, Enrico; Reddy, Vanga Siva; Cella, Rino

    2015-01-01

    Biofuels from renewable plant biomass are gaining momentum due to climate change related to atmospheric CO2 increase. However, the production cost of enzymes required for cellulosic biomass saccharification is a major limiting step in this process. Low-cost production of large amounts of recombinant enzymes by transgenic plants was proposed as an alternative to the conventional microbial based fermentation. A number of studies have shown that chloroplast-based gene expression offers several advantages over nuclear transformation due to efficient transcription and translation systems and high copy number of the transgene. In this study, we expressed in tobacco chloroplasts microbial genes encoding five cellulases and a polygalacturonase. Leaf extracts containing the recombinant enzymes showed the ability to degrade various cell-wall components under different conditions, singly and in combinations. In addition, our group also tested a previously described thermostable xylanase in combination with a cellulase and a polygalacturonase to study the cumulative effect on the depolymerization of a complex plant substrate. Our results demonstrate the feasibility of using transplastomic tobacco leaf extracts to convert cell-wall polysaccharides into reducing sugars, fulfilling a major prerequisite of large scale availability of a variety of cell-wall degrading enzymes for biofuel industry. PMID:26137472

  11. Production by Tobacco Transplastomic Plants of Recombinant Fungal and Bacterial Cell-Wall Degrading Enzymes to Be Used for Cellulosic Biomass Saccharification.

    PubMed

    Longoni, Paolo; Leelavathi, Sadhu; Doria, Enrico; Reddy, Vanga Siva; Cella, Rino

    2015-01-01

    Biofuels from renewable plant biomass are gaining momentum due to climate change related to atmospheric CO2 increase. However, the production cost of enzymes required for cellulosic biomass saccharification is a major limiting step in this process. Low-cost production of large amounts of recombinant enzymes by transgenic plants was proposed as an alternative to the conventional microbial based fermentation. A number of studies have shown that chloroplast-based gene expression offers several advantages over nuclear transformation due to efficient transcription and translation systems and high copy number of the transgene. In this study, we expressed in tobacco chloroplasts microbial genes encoding five cellulases and a polygalacturonase. Leaf extracts containing the recombinant enzymes showed the ability to degrade various cell-wall components under different conditions, singly and in combinations. In addition, our group also tested a previously described thermostable xylanase in combination with a cellulase and a polygalacturonase to study the cumulative effect on the depolymerization of a complex plant substrate. Our results demonstrate the feasibility of using transplastomic tobacco leaf extracts to convert cell-wall polysaccharides into reducing sugars, fulfilling a major prerequisite of large scale availability of a variety of cell-wall degrading enzymes for biofuel industry.

  12. Cell wall-degrading enzymes enlarge the pore size of intervessel pit membranes in healthy and Xylella fastidiosa-infected grapevines.

    PubMed

    Pérez-Donoso, Alonso G; Sun, Qiang; Roper, M Caroline; Greve, L Carl; Kirkpatrick, Bruce; Labavitch, John M

    2010-03-01

    The pit membrane (PM) is a primary cell wall barrier that separates adjacent xylem water conduits, limiting the spread of xylem-localized pathogens and air embolisms from one conduit to the next. This paper provides a characterization of the size of the pores in the PMs of grapevine (Vitis vinifera). The PM porosity (PMP) of stems infected with the bacterium Xylella fastidiosa was compared with the PMP of healthy stems. Stems were infused with pressurized water and flow rates were determined; gold particles of known size were introduced with the water to assist in determining the size of PM pores. The effect of introducing trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (CDTA), oligogalacturonides, and polygalacturonic acid into stems on water flux via the xylem was also measured. The possibility that cell wall-degrading enzymes could alter the pore sizes, thus facilitating the ability of X. fastidiosa to cross the PMs, was tested. Two cell wall-degrading enzymes likely to be produced by X. fastidiosa (polygalactuoronase and endo-1,4- beta -glucanase) were infused into stems, and particle passage tests were performed to check for changes in PMP. Scanning electron microscopy of control and enzyme-infused stem segments revealed that the combination of enzymes opened holes in PMs, probably explaining enzyme impacts on PMP and how a small X. fastidiosa population, introduced into grapevines by insect vectors, can multiply and spread throughout the vine and cause Pierce's disease.

  13. Production of plant cell wall degrading enzymes by monoculture and co-culture of Aspergillus niger and Aspergillus terreus under SSF of banana peels.

    PubMed

    Rehman, Shazia; Aslam, Hina; Ahmad, Aqeel; Khan, Shakeel Ahmed; Sohail, Muhammad

    2014-01-01

    Filamentous fungi are considered to be the most important group of microorganisms for the production of plant cell wall degrading enzymes (CWDE), in solid state fermentations. In this study, two fungal strains Aspergillus niger MS23 and Aspergillus terreus MS105 were screened for plant CWDE such as amylase, pectinase, xylanase and cellulases (β-glucosidase, endoglucanase and filterpaperase) using a novel substrate, Banana Peels (BP) for SSF process. This is the first study, to the best of our knowledge, to use BP as SSF substrate for plant CWDE production by co-culture of fungal strains. The titers of pectinase were significantly improved in co-culture compared to mono-culture. Furthermore, the enzyme preparations obtained from monoculture and co-culture were used to study the hydrolysis of BP along with some crude and purified substrates. It was observed that the enzymatic hydrolysis of different crude and purified substrates accomplished after 26 h of incubation, where pectin was maximally hydrolyzed by the enzyme preparations of mono and co-culture. Along with purified substrates, crude materials were also proved to be efficiently degraded by the cocktail of the CWDE. These results demonstrated that banana peels may be a potential substrate in solid-state fermentation for the production of plant cell wall degrading enzymes to be used for improving various biotechnological and industrial processes.

  14. Production of plant cell wall degrading enzymes by monoculture and co-culture of Aspergillus niger and Aspergillus terreus under SSF of banana peels

    PubMed Central

    Rehman, Shazia; Aslam, Hina; Ahmad, Aqeel; Khan, Shakeel Ahmed; Sohail, Muhammad

    2014-01-01

    Filamentous fungi are considered to be the most important group of microorganisms for the production of plant cell wall degrading enzymes (CWDE), in solid state fermentations. In this study, two fungal strains Aspergillus niger MS23 and Aspergillus terreus MS105 were screened for plant CWDE such as amylase, pectinase, xylanase and cellulases (β-glucosidase, endoglucanase and filterpaperase) using a novel substrate, Banana Peels (BP) for SSF process. This is the first study, to the best of our knowledge, to use BP as SSF substrate for plant CWDE production by co-culture of fungal strains. The titers of pectinase were significantly improved in co-culture compared to mono-culture. Furthermore, the enzyme preparations obtained from monoculture and co-culture were used to study the hydrolysis of BP along with some crude and purified substrates. It was observed that the enzymatic hydrolysis of different crude and purified substrates accomplished after 26 h of incubation, where pectin was maximally hydrolyzed by the enzyme preparations of mono and co-culture. Along with purified substrates, crude materials were also proved to be efficiently degraded by the cocktail of the CWDE. These results demonstrated that banana peels may be a potential substrate in solid-state fermentation for the production of plant cell wall degrading enzymes to be used for improving various biotechnological and industrial processes. PMID:25763058

  15. Is nanotechnology revolutionizing the paint and lacquer industry? A critical opinion.

    PubMed

    Kaiser, Jean-Pierre; Zuin, Stefano; Wick, Peter

    2013-01-01

    Many paints for indoor and outdoor applications contain biocides and additives for protection against microbial, physical and chemical deterioration. The biocides should remain active as long as they are incorporated in the paint. Protection against microbial colonization should last at least a decade. Once the biocides are released they should degrade within a short time so that no accumulation in the environment can occur. The paint industry is not only focusing their research in producing better paint formulations with degradable biocides: they also consider using nanomaterials, such as nanosilver, nanocopper, nanozinc oxide, photocatalytic-active nanotitanium dioxide and nanosilica dioxide as additives for the protection of paints, against microbial degradation and physical and chemical deterioration. In the future nanomaterials should replace biodegradable biocides and improve the paint properties as well as impede colonization by microorganisms. At the time there is no guarantee that the nanomaterials in paints and façades will fulfill their task in the long run, since there are no long term studies available. From nanosilver doped paints it is known that silver is easily washed out by rain. Photocatalytic active nanotitanium dioxide adsorbs ultra violet light (UV-light) and generates hydroxyl radicals, which not only inhibit microbial growth but can also initiate or accelerate the photocatalytic degradation of the paint matrix. Thus at this time it is still unknown if it makes sense to incorporate nanomaterials into paints. Intensive research and development are still needed in order to find the answers.

  16. The Elicitation of Ethylene Biosynthesis by a Trichoderma Xylanase Is Not Related to the Cell Wall Degradation Activity of the Enzyme.

    PubMed Central

    Sharon, A.; Fuchs, Y.; Anderson, J. D.

    1993-01-01

    A [beta]-1,4-endoxylanase (EIX) isolated from Trichoderma viride elicits plant defense responses in certain tobacco (Nicotiana tabacum L.) cultivars in addition to its xylan degradation activity. It was not clear whether elicitation occurs by cell wall fragments released by the enzymic activity or by the xylanase protein interacting directly with the plant cells. We used protoplasts isolated from tobacco leaves to test whether the cell wall is required for the stimulation of ethylene biosynthesis by EIX. Protoplasts of tobacco (cv Xanthi) responded to treatment with the EIX, as indicated by an increased production of ethylene and the loss of protoplast viability. Protoplasts prepared from ethylene-pretreated leaves produced more ethylene and had higher rates of cell death in response to EIX than protoplasts prepared from nonethylene-treated leaves. Protoplasts of an EIX-insensitive cultivar of tobacco (Hicks) were insensitive to high concentrations of EIX. The addition of a crude cell wall preparation to protoplasts during incubation with EIX did not enhance the induction of ethylene biosynthesis by nonsaturating as well as saturating concentrations of EIX. These data indicate that the xylanase activity of EIX is unrelated to the elicitation of ethylene biosynthesis through the production of some cell wall fragment, since the protein per se appears capable of eliciting ethylene biosynthesis in protoplasts. PMID:12231909

  17. The Elicitation of Ethylene Biosynthesis by a Trichoderma Xylanase Is Not Related to the Cell Wall Degradation Activity of the Enzyme.

    PubMed

    Sharon, A.; Fuchs, Y.; Anderson, J. D.

    1993-08-01

    A [beta]-1,4-endoxylanase (EIX) isolated from Trichoderma viride elicits plant defense responses in certain tobacco (Nicotiana tabacum L.) cultivars in addition to its xylan degradation activity. It was not clear whether elicitation occurs by cell wall fragments released by the enzymic activity or by the xylanase protein interacting directly with the plant cells. We used protoplasts isolated from tobacco leaves to test whether the cell wall is required for the stimulation of ethylene biosynthesis by EIX. Protoplasts of tobacco (cv Xanthi) responded to treatment with the EIX, as indicated by an increased production of ethylene and the loss of protoplast viability. Protoplasts prepared from ethylene-pretreated leaves produced more ethylene and had higher rates of cell death in response to EIX than protoplasts prepared from nonethylene-treated leaves. Protoplasts of an EIX-insensitive cultivar of tobacco (Hicks) were insensitive to high concentrations of EIX. The addition of a crude cell wall preparation to protoplasts during incubation with EIX did not enhance the induction of ethylene biosynthesis by nonsaturating as well as saturating concentrations of EIX. These data indicate that the xylanase activity of EIX is unrelated to the elicitation of ethylene biosynthesis through the production of some cell wall fragment, since the protein per se appears capable of eliciting ethylene biosynthesis in protoplasts.

  18. Degradation of the fungal cell wall by clostridial strains isolated from soil subjected to biological soil disinfestation and biocontrol of Fusarium wilt disease of spinach.

    PubMed

    Ueki, Atsuko; Takehara, Toshiaki; Ishioka, Gen; Kaku, Nobuo; Ueki, Katsuji

    2017-10-01

    Biological soil disinfestation (BSD) involves elimination of soil-borne plant pathogens in an environmentally friendly manner. Two anaerobic bacterial strains (H110 and TB8) isolated from BSD-treated soil samples were analyzed for their roles in elimination of pathogenic fungi. The two strains were identified as Clostridium beijerinckii based on 16S rRNA gene sequences and phenotypic properties. The strains fermented various carbohydrates and produced acetate, butyrate, and n-butanol as major products as well as abundant gases (H2 and CO2). For evaluation of the antifungal potential of these strains, cells of a pathogen (spinach wilt disease, Fusarium oxysporum f. sp. spinaciae) were co-inoculated into anaerobic media with each anaerobic strain. After incubation for ~3 weeks at 30 °C, 10-30% of the cells of the pathogen survived when incubated without the anaerobic isolates, whereas the pathogen was eliminated when co-incubated with each anaerobe because of the growth of the anaerobic bacterium. It was found by microscopic examination that mycelial cells of the fungal pathogen were severely degraded during the first 3-7 days of the co-incubation. The two strains utilized major cell wall polysaccharides of ascomycetous fungi-chitosan and ß-1,3-glucan (curdlan and laminarin)-as fermentative substrates added to the medium. Furthermore, both isolates degraded a cell wall preparation isolated from the mycelium of the Fusarium pathogen of spinach wilt disease. We concluded that the two anaerobic strains kill the pathogen of spinach wilt disease by degrading major fungal cell wall components as antifungal activities.

  19. Heat Resistant Paint

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The racing car shown is one of many coated with an inorganic paint that protects "hot parts" of automotive vehicles. Developed and manufactured by Sperex Corporation, Gardena, California, the durable, heat-resistant paint is used on car and truck exhaust systems, firewalls, brake drums and engine manifolds. NASA technology contributed to development of the paint. Sperex was provided a technical support packa'ge detailing the research of Goddard Space Flight Center on long-life inorganic coatings. The information helped Sperex perfect its own formulations.

  20. Characterization of low-VOC latex paints: Volatile organic compound content, VOC and aldehyde emissions, and paint performance. Final report, January 1997--January 1999

    SciTech Connect

    Fortmann, R.; Lao, H.C.; Ng, A.; Roache, N.

    1999-04-01

    The report gives results of laboratory tests to evaluate commercially available latex paints advertised as `low-odor,` `low-VOC (volatile organic compound),` or `no-VOC.` Measurements were performed to quantify the total content of VOCs in the paints and to identify the predominant VOCs and aldehydes in the emissions following application to test substrates. The performance of the paints was evaluated and compared to that of commonly used conventional latex paints by American Society for Testing and Materials (ASTM) standard methods that measured parameters such as scrubbability, cleanability, and hiding power. The report describes the paints that were tested, the test methods, and the experimental data. Results are presented that can be used to evaluate the low-odor/low-VOC paints as alternatives to conventional latex wall paints that contain and emit higher concentrations of VOCs.

  1. Analysis of expressed sequence tags and identification of genes encoding cell-wall-degrading enzymes from the fungivorous nematode Aphelenchus avenae.

    PubMed

    Karim, Nurul; Jones, John T; Okada, Hiroaki; Kikuchi, Taisei

    2009-11-16

    The fungivorus nematode, Aphelenchus avenae is widespread in soil and is found in association with decaying plant material. This nematode is also found in association with plants but its ability to cause plant disease remains largely undetermined. The taxonomic position and intermediate lifestyle of A. avenae make it an important model for studying the evolution of plant parasitism within the Nematoda. In addition, the exceptional capacity of this nematode to survive desiccation makes it an important system for study of anhydrobiosis. Expressed sequence tag (EST) analysis may therefore be useful in providing an initial insight into the poorly understood genetic background of A. avenae. We present the generation, analysis and annotation of over 5,000 ESTs from a mixed-stage A. avenae cDNA library. Clustering of 5,076 high-quality ESTs resulted in a set of 2,700 non-redundant sequences comprising 695 contigs and 2,005 singletons. Comparative analyses indicated that 1,567 (58.0%) of the cluster sequences had homologues in Caenorhabditis elegans, 1,750 (64.8%) in other nematodes, 1,321(48.9%) in organisms other than nematodes, and 862 (31.9%) had no significant match to any sequence in current protein or nucleotide databases. In addition, 1,100 (40.7%) of the sequences were functionally classified using Gene Ontology (GO) hierarchy. Similarity searches of the cluster sequences identified a set of genes with significant homology to genes encoding enzymes that degrade plant or fungal cell walls. The full length sequences of two genes encoding glycosyl hydrolase family 5 (GHF5) cellulases and two pectate lyase genes encoding polysaccharide lyase family 3 (PL3) proteins were identified and characterized. We have described at least 2,214 putative genes from A. avenae and identified a set of genes encoding a range of cell-wall-degrading enzymes. This EST dataset represents a starting point for studies in a number of different fundamental and applied areas. The presence of

  2. Analysis of expressed sequence tags and identification of genes encoding cell-wall-degrading enzymes from the fungivorous nematode Aphelenchus avenae

    PubMed Central

    2009-01-01

    Background The fungivorus nematode, Aphelenchus avenae is widespread in soil and is found in association with decaying plant material. This nematode is also found in association with plants but its ability to cause plant disease remains largely undetermined. The taxonomic position and intermediate lifestyle of A. avenae make it an important model for studying the evolution of plant parasitism within the Nematoda. In addition, the exceptional capacity of this nematode to survive desiccation makes it an important system for study of anhydrobiosis. Expressed sequence tag (EST) analysis may therefore be useful in providing an initial insight into the poorly understood genetic background of A. avenae. Results We present the generation, analysis and annotation of over 5,000 ESTs from a mixed-stage A. avenae cDNA library. Clustering of 5,076 high-quality ESTs resulted in a set of 2,700 non-redundant sequences comprising 695 contigs and 2,005 singletons. Comparative analyses indicated that 1,567 (58.0%) of the cluster sequences had homologues in Caenorhabditis elegans, 1,750 (64.8%) in other nematodes, 1,321(48.9%) in organisms other than nematodes, and 862 (31.9%) had no significant match to any sequence in current protein or nucleotide databases. In addition, 1,100 (40.7%) of the sequences were functionally classified using Gene Ontology (GO) hierarchy. Similarity searches of the cluster sequences identified a set of genes with significant homology to genes encoding enzymes that degrade plant or fungal cell walls. The full length sequences of two genes encoding glycosyl hydrolase family 5 (GHF5) cellulases and two pectate lyase genes encoding polysaccharide lyase family 3 (PL3) proteins were identified and characterized. Conclusion We have described at least 2,214 putative genes from A. avenae and identified a set of genes encoding a range of cell-wall-degrading enzymes. This EST dataset represents a starting point for studies in a number of different fundamental and

  3. Oligogalacturonide-mediated induction of a gene involved in jasmonic acid synthesis in response to the cell-wall-degrading enzymes of the plant pathogen Erwinia carotovora.

    PubMed

    Norman, C; Vidal, S; Palva, E T

    1999-07-01

    Identification of Arabidopsis thaliana genes responsive to plant cell-wall-degrading enzymes of Erwinia carotovora subsp. carotovora led to the isolation of a cDNA clone with high sequence homology to the gene for allene oxide synthase, an enzyme involved in the biosynthesis of jasmonates. Expression of the corresponding gene was induced by the extracellular enzymes from this pathogen as well as by treatment with methyl jasmonate and short oligogalacturonides (OGAs). This suggests that OGAs are involved in the induction of the jasmonate pathway during plant defense response to E. carotovora subsp. carotovora attack.

  4. Degradation of optical properties of a film-type single-wall carbon nanotubes saturable absorber (SWNT-SA) with an Er-doped all-fiber laser.

    PubMed

    Ryu, Sung Yoon; Kim, Kyung-Soo; Kim, Jungwon; Kim, Soohyun

    2012-06-04

    Single-wall carbon nanotubes (SWNTs) are promising materials for saturable absorbers (SAs) in mode-locked lasers. However it has been widely recognized that the degradation of optical properties of film-type SWNTs used in femtosecond mode-locked lasers limits the achievable long-term stability of such lasers. In this paper, we study the degradation of optical properties of SWNT-SA fabricated as sandwich type using HiPCO SWNTs with an Er-doped all-fiber laser. The thresholds of laser pump power are examined to avoid the damage of the SWNT-SA. Based on the proposed analysis, it is shown that all-fiber laser pulses of 300 fs pulse width, 3.85 mW average output power, 211.7 MW/cm² peak intensity and 69.9 MHz repetition rate can be reliably generated without any significant damage to the SWNT-SA film.

  5. Mycoparasitism of endophytic fungi isolated from reed on soilborne phytopathogenic fungi and production of cell wall-degrading enzymes in vitro.

    PubMed

    Cao, Ronghua; Liu, Xiaoguang; Gao, Kexiang; Mendgen, Kurt; Kang, Zhensheng; Gao, Jianfeng; Dai, Yang; Wang, Xue

    2009-12-01

    Antagonism of three endophytic fungi isolated from common reed (Phragmites australis) against eight soilborne pathogenic fungi was investigated on potato dextrose agar by light microscopy, scanning electron microscopy, and transmission electron microscopy. Inhibitory zones were not observed. The microscopical studies suggested that the endophytes inhibit growth of soilborne pathogens by means of coiling around hyphae and, after penetration, the degradation of hyphal cytoplasm. Since penetration of hyphae seems to play a major role in parasitism, we studied the production of cell wall degrading enzymes by the three endophytes. Choiromyces aboriginum produced higher activities of beta-1,3-glucanases compared to Stachybotrys elegans and Cylindrocarpon sp. For C. aboriginum and S. elegans, colloidal chitin was the best substrate for the induction of beta-1,3-glucanases and chitinases, respectively. This result suggests that mycoparasitism by endophytes on soilborne plant pathogens can be explained by their mycoparasitic activity.

  6. Horizontal gene transfer and functional diversification of plant cell wall degrading polygalacturonases: Key events in the evolution of herbivory in beetles.

    PubMed

    Kirsch, Roy; Gramzow, Lydia; Theißen, Günter; Siegfried, Blair D; Ffrench-Constant, Richard H; Heckel, David G; Pauchet, Yannick

    2014-09-01

    Plant cell walls are the largest reservoir of organic carbon on earth. To breach and utilize this carbohydrate-rich protective barrier, microbes secrete plant cell wall degrading enzymes (PCWDEs) targeting pectin, cellulose and hemicelluloses. There is a growing body of evidence that genomes of some herbivorous insects also encode PCWDEs, raising questions about their evolutionary origins and functions. Among herbivorous beetles, pectin-degrading polygalacturonases (PGs) are found in the diverse superfamilies Chrysomeloidea (leaf beetles, long-horn beetles) and Curculionoidea (weevils). Here our aim was to test whether these arose from a common ancestor of beetles or via horizontal gene transfer (HGT), and whether PGs kept their ancestral function in degrading pectin or evolved novel functions. Transcriptome data derived from 10 beetle species were screened for PG-encoding sequences and used for phylogenetic comparisons with their bacterial, fungal and plant counterparts. These analyses revealed a large family of PG-encoding genes of Chrysomeloidea and Curculionoidea sharing a common ancestor, most similar to PG genes of ascomycete fungi. In addition, 50 PGs from beetle digestive systems were heterologously expressed and functionally characterized, showing a set of lineage-specific consecutively pectin-degrading enzymes, as well as conserved but enzymatically inactive PG proteins. The evidence indicates that a PG gene was horizontally transferred ∼200 million years ago from an ascomycete fungus to a common ancestor of Chrysomeloidea and Curculionoidea. This has been followed by independent duplications in these two lineages, as well as independent replacement in two sublineages of Chrysomeloidea by two other subsequent HGTs. This origin, leading to subsequent functional diversification of the PG gene family within its new hosts, was a key event promoting the evolution of herbivory in these beetles. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Chromate Dermatitis from Paint

    PubMed Central

    Engel, H. O.; Calnan, C. D.

    1963-01-01

    Among 250 workers engaged on wet sandpapering of primer paint on car bodies 65 developed a contact dermatitis. The average latent period before dermatitis developed was 4·6 months: only 60% of the patients made a completely satisfactory recovery. The average duration of dermatitis was 5·3 months. Two thirds of the men used one of two barrier creams supplied, while one third used none. Routine patch testing showed that the majority was allergic to chromate. It was found that a primer paint contained zinc chromate, which had been introduced into the paint by the manufacturers shortly before the first cases occurred. Removal of chromate from the paint resulted in a prompt cessation of new cases of dermatitis. Images PMID:14046155

  8. Paint and Pregnancy

    MedlinePlus

    ... with some studies showing no increased risk. An occupational health specialist or industrial hygienist may be able to ... little is known about exposure to paint during breastfeeding, but it is unlikely that typical low- level ...

  9. Artists Paint ... Landscapes

    ERIC Educational Resources Information Center

    Herberholz, Barbara

    2012-01-01

    This article features the painting "View of Toledo," based on Toledo, a very old city located on a high plateau in Spain. By the time the artist El Greco painted the picture, he had lived there for 31 years. When one looks at the picture, one will see a storm approaching and will see the city as if it were lit by a flash of lightning. What main…

  10. Robotic Paint Stripping Cell

    DTIC Science & Technology

    1993-11-01

    based controls are used for all F-1 a substrate materials, Inc, ding graphite-epoxy composhes. The RPSC is a fully automated plastic media blast paint...based controls are used for all F.16 substrate materials, including graphite-epoxy composites. The RPSC is a fully automated plastic media blast...control the paint stripping rate and prevent overblasting of the substrate . Four halogen lamps provide an infrared-rich light source which is reflected

  11. Artists Paint ... Landscapes

    ERIC Educational Resources Information Center

    Herberholz, Barbara

    2012-01-01

    This article features the painting "View of Toledo," based on Toledo, a very old city located on a high plateau in Spain. By the time the artist El Greco painted the picture, he had lived there for 31 years. When one looks at the picture, one will see a storm approaching and will see the city as if it were lit by a flash of lightning. What main…

  12. Pressure-sensitive paint as a distributed optical microphone array.

    PubMed

    Gregory, James W; Sullivan, John P; Wanis, Sameh S; Komerath, Narayanan M

    2006-01-01

    Pressure-sensitive paint is presented and evaluated in this article as a quantitative technique for measurement of acoustic pressure fluctuations. This work is the culmination of advances in paint technology which enable unsteady measurements of fluctuations over 10 kHz at pressure levels as low as 125 dB. Pressure-sensitive paint may be thought of as a nano-scale array of optical microphones with a spatial resolution limited primarily by the resolution of the imaging device. Thus, pressure-sensitive paint is a powerful tool for making high-amplitude sound pressure measurements. In this work, the paint was used to record ensemble-averaged, time-resolved, quantitative measurements of two-dimensional mode shapes in an acoustic resonance cavity. A wall-mounted speaker generated nonlinear, standing acoustic waves in a rigid enclosure measuring 216 mm wide, 169 mm high, and 102 mm deep. The paint recorded the acoustic surface pressures of the (1,1,0) mode shape at approximately 1.3 kHz and a sound pressure level of 145.4 dB. Results from the paint are compared with data from a Kulite pressure transducer, and with linear acoustic theory. The paint may be used as a diagnostic technique for ultrasonic tests where high spatial resolution is essential, or in nonlinear acoustic applications such as shock tubes.

  13. Investigation on the hazing of a Brazilian contemporary painting

    NASA Astrophysics Data System (ADS)

    Puglieri, Thiago S.; Lavezzo, Ariane S.; Santos, Isabela F. S. dos; de Faria, Dalva L. A.

    2016-04-01

    A whitish crystalline-like coating was observed on the surface of the painting "Incêndio", 1990, produced by Emmanuel Nassar and awarded at the 6th Biennial of Cuenca. This work belongs to the Contemporary Art Museum of the University of São Paulo (MAC-USP) and such coating modified the artwork characteristics, causing an unpleasant effect and compromising its exhibition. The choice of the proper conservation and restoration strategies involves the understanding of the degradation process, demanding the identification of the chemical compounds formed on the painting surface, as well as of the other components in the painting. The results here obtained from Raman and optical microscopies, FTIR-ATR, SEM-EDS and GC-MS, revealed that the efflorescence chemical composition is almost only palmitic acid, with minor contents of stearic acid and their methyl esters, and that the paints are composed by chrome yellow, amorphous carbon and toluidine red pigment; an aluminum silicate filler in the black paint applied on the aluminum ground was also detected. Hierarchical Cluster Analyses (HCA) of the Raman spectra also revealed that the concentration of the efflorescence minor components depends on the paint composition. It was suggested, therefore, that the degradation process resulted from segregation and migration of mainly palmitic acid from the dried paints. Restoration methodologies used in similar cases, as well as factors that contribute to this process, were discussed.

  14. Investigation on the hazing of a Brazilian contemporary painting.

    PubMed

    Puglieri, Thiago S; Lavezzo, Ariane S; dos Santos, Isabela F S; de Faria, Dalva L A

    2016-04-15

    A whitish crystalline-like coating was observed on the surface of the painting "Incêndio", 1990, produced by Emmanuel Nassar and awarded at the 6th Biennial of Cuenca. This work belongs to the Contemporary Art Museum of the University of São Paulo (MAC-USP) and such coating modified the artwork characteristics, causing an unpleasant effect and compromising its exhibition. The choice of the proper conservation and restoration strategies involves the understanding of the degradation process, demanding the identification of the chemical compounds formed on the painting surface, as well as of the other components in the painting. The results here obtained from Raman and optical microscopies, FTIR-ATR, SEM-EDS and GC-MS, revealed that the efflorescence chemical composition is almost only palmitic acid, with minor contents of stearic acid and their methyl esters, and that the paints are composed by chrome yellow, amorphous carbon and toluidine red pigment; an aluminum silicate filler in the black paint applied on the aluminum ground was also detected. Hierarchical Cluster Analyses (HCA) of the Raman spectra also revealed that the concentration of the efflorescence minor components depends on the paint composition. It was suggested, therefore, that the degradation process resulted from segregation and migration of mainly palmitic acid from the dried paints. Restoration methodologies used in similar cases, as well as factors that contribute to this process, were discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Long-term selective degradation of organic-walled dinoflagellate cysts in a Maderia Abyssal Plain turbidite

    NASA Astrophysics Data System (ADS)

    Gray, Daniel D.; Versteegh, Gerard J. M.; Zonneveld, Karin A. F.

    2017-04-01

    Post-depositional sedimentary dinoflagellate cyst degradation is well documented under oxic conditions, a process characterised by the preferential loss of "S-cysts" at elevated ambient oxygen concentrations. Establishing a quantitative relationship between degradation rates and aerobic exposure would allow paleo-bottom oxygen water profiles to be reconstructed. Here we trace the long-term (centennial-millennial scale) degradation pattern of a dinocyst assemblage from the F-turbidite of core GeoB20305-7 retrieved at Maderia Abyssal Plain (MAP), with reference to a suite of inorganic and organic geochemical profiles. A downward-migrating oxidation front advances through the the upper part of the depositional unit, resulting in a near-total loss of the Peridiniales cyst fraction dominated by Brigantedinium spp. and Echinidinium spp. specimens. In contrast, Gonyaulacales species have subdued degradation responses resulting in the progressive reconstitution of the cyst assemblage away from its source signal. Assuming a diffusion-dominated migration of the oxidation front and a basic parameterisation of boundary conditions we estimate the oxygen exposure time (OET) of the oxidised section to be 5000 years. The resulting degradation profile is well-fitted by an exponential decay curve. Implications of these observations are discussed with regard to existing schemes for dinoflagellate based proxy interpretation in oxic environments.

  16. Permanent-Change Thermal Paints for Hypersonic Flight-Test

    DTIC Science & Technology

    2010-09-24

    initial test case for post recovery handling and analysis of the painted surfaces. • Investigate the bonding of the paints to a range of materials and...heating during flight and can quickly reach elevated temperature. All engineering materials degrade in mechanical performance at elevated temperature...and this can be severe for the candidate materials and conditions for the airframes of hypersonic flight-test vehicles. To maintain structural mass

  17. Methylisothiazolinone and benzisothiazolinone are widely used in paint: a multicentre study of paints from five European countries.

    PubMed

    Schwensen, Jakob F; Lundov, Michael D; Bossi, Rossana; Banerjee, Piu; Giménez-Arnau, Elena; Lepoittevin, Jean-Pierre; Lidén, Carola; Uter, Wolfgang; Yazar, Kerem; White, Ian R; Johansen, Jeanne D

    2015-03-01

    In view of the current epidemic of contact allergy to methylisothiazolinone (MI), it is important to clarify the extent of use of MI and related isothiazolinones in paints currently available for the consumer and worker in Europe. To elucidate the use and concentrations of MI, methylchloroisothiazolinone (MCI) and benzisothiazolinone (BIT) in paints on the European retail market. Wall paints (n = 71) were randomly purchased in retail outlets in five European countries. The paints were quantitatively analysed for their contents of MI, MCI and BIT by high-performance liquid chromatography coupled to tandem mass spectrometry. MI was found in 93.0% (n = 66) of the paints, with concentrations ranging from 0.7 to 180.9 ppm, MCI in 23.9% (n = 17), ranging from 0.26 to 11.4 ppm, and BIT in 95.8% (n = 68), ranging from 0.1 to 462.5 ppm. High concentrations of MI were found in paints from all five countries. Paints purchased in Denmark and Sweden contained especially high concentrations of BIT. The use of MI across European countries is extensive. In view of the ongoing epidemic of MI contact allergy, an evaluation of the safety of MI in paints is needed. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Effects of cold storage and 1-methylcyclopropene treatments on ripening and cell wall degrading in rabbiteye blueberry (Vaccinium ashei) fruit.

    PubMed

    Deng, Jia; Shi, Zhengjun; Li, Xianzhong; Liu, Huimin

    2014-06-01

    The effect of postharvest 1-methylcyclopropene and/or cold storage application on texture quality parameters during storage was determined. The changes in fruit quality (including weight loss, firmness, total soluble solids content, and ethylene production), cell wall material (including water-soluble fraction, ethylenediaminetetraacetic acid-soluble fraction, Na2CO3-soluble fraction, 4% KOH-soluble fraction, and 14% KOH-soluble fraction), and cell wall hydrolase activities (including polygalacturonase, endo-1,4-beta-D-glucanase, pectinesterase, alpha-L-arabinofuranosidase, and beta-galactosidase) were periodically measured up to 25 days after postharvest treatments. The application of cold storage reduced weight loss, ethylene production, and delayed ripening of blueberry fruit. The inhibition of senescence was associated with suppressed increase in cell wall hydrolase activities and retarded solubilization of pectins and hemicelluloses. Furthermore, no obvious differences in firmness, weight loss, ethylene production, and cell wall hydrolase activities between fruits with or without 1-methylcyclopropene application were observed, while significant lower levels of the detected parameters were found in cold storage fruit compared with fruit stored in room temperature. Thus, cold storage can be viewed as an effective means to extend the shelf life of blueberry fruit.

  19. Solar photocatalytic degradation of 2,6-dinitro-p-cresol (DNPC) using multi-walled carbon nanotubes (MWCNTs)-TiO(2) composite photocatalysts.

    PubMed

    Wang, Hui; Wang, Hui-Long; Jiang, Wen-Feng

    2009-05-01

    Multi-walled carbon nanotubes (MWCNTs)-TiO(2) composite photocatalysts with excellent activity were prepared by sol-gel method in order to investigate its photocatalytic activity under solar irradiation for the degradation of 2,6-dinitro-p-cresol (DNPC) in aqueous solution. The prepared composite were analyzed by XRD, FTIR, SEM, TEM, TG-DTA and UV-vis absorption spectra techniques. The results showed that the composite can cause an obvious red shift of UV-vis spectra compared with pure TiO(2). The degradation of DNPC by MWCNTs-TiO(2) composite photocatalysts under solar irradiation was systematically studied by varying the experimental parameters such as pH value, irradiation time, the initial substrate concentration, reaction temperature, catalyst concentration, etc. The optimal conditions were a DNPC concentration of 33.4 mgL(-1) at pH 6.0 with MWCNTs-TiO(2) concentration of 6.0gL(-1) under solar irradiation for the illumination of 150 min. The presence of MWCNTs can enhance the photoefficiency of TiO(2). The highest efficiency on photodegradation of DNPC can be achieved with an optimal MWCNTs/TiO(2) mass ratio of 0.05%. The photocatalytic degradation of DNPC obeys a pseudo-first-order behavior according to the Langmuir-Hinshelwood model, and possible decomposing mechanisms are also discussed. The photocatalyst was used for five cycles with photocatalytic degradation efficiency still higher than 96%. The results of the study showed the feasible and potential use of MWCNTs-TiO(2) composite in degradation of toxic organic pollutants.

  20. International forensic automotive paint database

    NASA Astrophysics Data System (ADS)

    Bishea, Gregory A.; Buckle, Joe L.; Ryland, Scott G.

    1999-02-01

    The Technical Working Group for Materials Analysis (TWGMAT) is supporting an international forensic automotive paint database. The Federal Bureau of Investigation and the Royal Canadian Mounted Police (RCMP) are collaborating on this effort through TWGMAT. This paper outlines the support and further development of the RCMP's Automotive Paint Database, `Paint Data Query'. This cooperative agreement augments and supports a current, validated, searchable, automotive paint database that is used to identify make(s), model(s), and year(s) of questioned paint samples in hit-and-run fatalities and other associated investigations involving automotive paint.

  1. Reading Through Paint

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Two-dimensional data matrix symbols, which contain encoded letters and numbers, are permanently etched on items for identification. They can store up to 100 times more information than traditional bar codes. While the symbols provide several advantages over bar codes, once they are covered by paint they can no longer be read by optical scanners. Since most products are painted eventually, this presents a problem for industries relying on the symbols for identification and tracking. In 1987, NASA s Marshall Space Flight Center began studying direct parts marking with matrix symbols in order to track millions of Space Shuttle parts. Advances in the technology proved that by incorporating magnetic properties into the paints, inks, and pastes used to apply the matrix symbols, the codes could be read by a magnetic scanner even after being covered with paint or other coatings. NASA received a patent for such a scanner in 1998, but the system it used for development was not portable and was too costly. A prototype was needed as a lead-in to a production model. In the summer of 2000, NASA began seeking companies to build a hand-held scanner that would detect the Read Through Paint data matrix identification marks containing magnetic materials through coatings.

  2. Experiments on Paint Rheology

    NASA Astrophysics Data System (ADS)

    Hartranft, Thomas J.; Settles, Gary S.

    1998-11-01

    We seek a better understanding of the atomization of paints for purposes of limiting the environmental impact of spray painting. However, to do so one must confront both the shear and extensional rheology of mobile non-Newtonian fluids whose very composition is often complex and even unknown. A conventional Couette rheometer yields data on paint shear behavior, but no commercial instrument is available to measure the extensional viscosity, which is believed to govern ligamentary breakup in spray painting. Here a converging-flow extensional rheometer has been built for this purpose. Flow rate and orifice pressure drop are measured and related to the rheological properties of the fluid. At first, experience was gained by visualizing in this device the flow of clear aqueous solutions of both Newtonian (glycerol) and non-Newtonian (polyacrylamide) thickeners. Commercial latex and marine paints were then tested, with the goal of characterizing their extensional behavior and the hope that they might be replaceable by simpler aqueous rheological "substitute" fluids insofar as their atomization behavior is concerned. (Research supported by the US Navy via the Penn State Applied Research Laboratory.)

  3. 1. Photocopy of painting (original painting in possesion of the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Photocopy of painting (original painting in possesion of the family of Judge Jasper Brinton, Cairo, Egypt) Thomas Eakins, Artist 1878 SIDE AND FRONT ELEVATIONS - Brinton 1704 House, Oakland Road (Birmingham Township), Dilworthtown, Chester County, PA

  4. 9. Photocopy of painting (Painted by the architect, Mr. Lee ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Photocopy of painting (Painted by the architect, Mr. Lee and presented to the Rev. J.J. Roberts, Rector, 1853-1866) April 1960 EXTERIOR, GENERAL VIEW - Church of the Holy Cross, State Route 261, Stateburg, Sumter County, SC

  5. Paint removal using lasers

    NASA Astrophysics Data System (ADS)

    Liu, Katherine; Garmire, Elsa

    1995-07-01

    Experiments to investigate the potential for practical laser graffiti-removal systems are reported. A universal engineering curve for the time needed for removal of paint from nonconductive substrates that was valid over a range of 107 in intensity was measured with a variety of lasers. Comparable times were measured for conductive substrates, when pulses shorter than the thermal conduction times were used. Analysis suggests that Q-switched Nd:YAG lasers may be the most efficient means for removing graffiti and other unwanted paint. An 1-m2 area of paint 14 mu m thick can be removed in approximately 10 min with a 50-Hz laser system of 15-W average power.

  6. Paint removal using lasers.

    PubMed

    Liu, K; Garmire, E

    1995-07-20

    Experiments to investigate the potential for practical laser graffiti-removal systems are reported. A universal engineering curve for the time needed for removal of paint from nonconductive substrates that was valid over a range of 10(7) in intensity was measured with a variety of lasers. Comparable times were measured for conductive substrates, when pulses shorter than the thermal conduction times were used. Analysis suggests that Q-switched Nd:YAG lasers may be the most efficient means for removing graffiti and other unwanted paint. An 1-m(2) area of paint 14 µm thick can be removed in approximately 10 min with a 50-Hz laser system of 15-W average power.

  7. VAB Flag Painting

    NASA Image and Video Library

    2002-01-01

    On platforms suspended from the top of the 525-foot-high VAB, workers use rollers and brushes to repaint the U.S. flag on the southwest side of the Vehicle Assembly Building. The flag spans an area 209 feet by 110 feet, or about 23, 437 square feet. Each stripe is 9 feet wide and each star is 6 feet in diameter. The logo is also being painted. Known as the "meatball," the logo measures 110 feet by 132 feet, or about 12,300 square feet. The flag and logo were last painted in 1998, honoring NASA's 40th anniversary.

  8. LSST Painting Risk Evaluation Memo

    SciTech Connect

    Wolfe, Justin E.

    2016-11-10

    The optics subsystem is required to paint the edges of optics black where possible. Due to the risks in applying the paint LSST requests a review of the impact of removing this requirement for the filters and L3.

  9. Process Waste Assessment - Paint Shop

    SciTech Connect

    Phillips, N.M.

    1993-06-01

    This Process Waste Assessment was conducted to evaluate hazardous wastes generated in the Paint Shop, Building 913, Room 130. Special attention is given to waste streams generated by the spray painting process because it requires a number of steps for preparing, priming, and painting an object. Also, the spray paint booth covers the largest area in R-130. The largest and most costly waste stream to dispose of is {open_quote}Paint Shop waste{close_quotes} -- a combination of paint cans, rags, sticks, filters, and paper containers. These items are compacted in 55-gallon drums and disposed of as solid hazardous waste. Recommendations are made for minimizing waste in the Paint Shop. Paint Shop personnel are very aware of the need to minimize hazardous wastes and are continuously looking for opportunities to do so.

  10. Miniature spray-painting booth

    NASA Technical Reports Server (NTRS)

    Fee, K. W.

    1970-01-01

    Transparent spray booth provides method for quality painting and repair of surfaces in clean room or other specialized environments. Overspray and virtually all contaminating vapor and odor can be eliminated. Touch-up painting is achieved with spray gun.

  11. For the Classroom: Fish Painting.

    ERIC Educational Resources Information Center

    Zimmerman, Sally

    1984-01-01

    Fish painting can be used to introduce basic and advanced subject-concepts, especially with students for whom tactile skill development is of particular importance. Materials, methods, and hints are presented along with a diagram of the painting procedure. (BC)

  12. RNA-Seq Analysis of the Expression of Genes Encoding Cell Wall Degrading Enzymes during Infection of Lupin (Lupinus angustifolius) by Phytophthora parasitica

    PubMed Central

    Blackman, Leila M.; Cullerne, Darren P.; Torreña, Pernelyn; Taylor, Jen; Hardham, Adrienne R.

    2015-01-01

    RNA-Seq analysis has shown that over 60% (12,962) of the predicted transcripts in the Phytophthora parasitica genome are expressed during the first 60 h of lupin root infection. The infection transcriptomes included 278 of the 431 genes encoding P. parasitica cell wall degrading enzymes. The transcriptome data provide strong evidence of global transcriptional cascades of genes whose encoded proteins target the main categories of plant cell wall components. A major cohort of pectinases is predominantly expressed early but as infection progresses, the transcriptome becomes increasingly dominated by transcripts encoding cellulases, hemicellulases, β-1,3-glucanases and glycoproteins. The most highly expressed P. parasitica carbohydrate active enzyme gene contains two CBM1 cellulose binding modules and no catalytic domains. The top 200 differentially expressed genes include β-1,4-glucosidases, β-1,4-glucanases, β-1,4-galactanases, a β-1,3-glucanase, an α-1,4-polygalacturonase, a pectin deacetylase and a pectin methylesterase. Detailed analysis of gene expression profiles provides clues as to the order in which linkages within the complex carbohydrates may come under attack. The gene expression profiles suggest that (i) demethylation of pectic homogalacturonan occurs before its deacetylation; (ii) cleavage of the backbone of pectic rhamnogalacturonan I precedes digestion of its side chains; (iii) early attack on cellulose microfibrils by non-catalytic cellulose-binding proteins and enzymes with auxiliary activities may facilitate subsequent attack by glycosyl hydrolases and enzymes containing CBM1 cellulose-binding modules; (iv) terminal hemicellulose backbone residues are targeted after extensive internal backbone cleavage has occurred; and (v) the carbohydrate chains on glycoproteins are degraded late in infection. A notable feature of the P. parasitica infection transcriptome is the high level of transcription of genes encoding enzymes that degrade β-1

  13. Thermal Control Paints on LDEF: Results of M0003 Sub-Experiment 18

    DTIC Science & Technology

    1993-01-15

    oxygen and UV radiation. Optical measure- ments of the samples were obtained using a Perkin-Elmer Lambda 9 UVNIS/ NIR spectropho- tometer. The diffuse...paints Chemglaze A276, S13GLO, and YB-7 1, and the black paint D- 11. The effects of low earth orbit, which include those induced by UV radiation and...LDEF darkened significantly due to UV -induced degradation of the paint’s binder, while leading-edge samples remained white but exhibited severe atomic

  14. MEASUREMENTS OF VOLATILE ORGANIC COMPOUNDS AND PARTICLES DURING APPLICATION OF LATEX PAINT WITH AN AIRLESS SPRAYER

    EPA Science Inventory

    The paper discusses experiments, conducted at EPA's Indoor Air Quality Research House, to measure airborne concentrations of volatile organic compounds (VOCs) and particles during and following the spray-application of latex wall paint. (NOTE: Paint may be applied indoors by a v...

  15. MEASUREMENTS OF VOLATILE ORGANIC COMPOUNDS AND PARTICLES DURING APPLICATION OF LATEX PAINT WITH AN AIRLESS SPRAYER

    EPA Science Inventory

    The paper discusses experiments, conducted at EPA's Indoor Air Quality Research House, to measure airborne concentrations of volatile organic compounds (VOCs) and particles during and following the spray-application of latex wall paint. (NOTE: Paint may be applied indoors by a v...

  16. Assessment of the impact of degraded shear wall stiffnesses on seismic plant risk and seismic design loads

    SciTech Connect

    Klamerus, E.W.; Bohn, M.P.; Johnson, J.J.; Asfura, A.P.; Doyle, D.J.

    1994-02-01

    Test results sponsored by the USNRC have shown that reinforced shear wall (Seismic Category I) structures exhibit stiffnesses and natural frequencies which are smaller than those calculated in the design process. The USNRC has sponsored Sandia National Labs to perform an evaluation of the effects of the reduced frequencies on several existing seismic PRAs in order to determine the seismic risk implications inherent in these test results. This report presents the results for the re-evaluation of the seismic risk for three nuclear power plants: the Peach Bottom Atomic Power Station, the Zion Nuclear Power Plant, and Arkansas Nuclear One -- Unit 1 (ANO-1). Increases in core damage frequencies for seismic initiated events at Peach Bottom were 25 to 30 percent (depending on whether LLNL or EPRI hazard curves were used). At the ANO-1 site, the corresponding increases in plant risk were 10 percent (for each set of hazard curves). Finally, at Zion, there was essentially no change in the computed core damage frequency when the reduction in shear wall stiffness was included. In addition, an evaluation of deterministic ``design-like`` structural dynamic calculations with and without the shear stiffness reductions was made. Deterministic loads calculated for these two cases typically increased on the order of 10 to 20 percent for the affected structures.

  17. Synergistic Effect of Different Plant Cell Wall-Degrading Enzymes Is Important for Virulence of Fusarium graminearum.

    PubMed

    Paccanaro, Maria Chiara; Sella, Luca; Castiglioni, Carla; Giacomello, Francesca; Martínez-Rocha, Ana Lilia; D'Ovidio, Renato; Schäfer, Wilhelm; Favaron, Francesco

    2017-11-01

    Endo-polygalacturonases (PGs) and xylanases have been shown to play an important role during pathogenesis of some fungal pathogens of dicot plants, while their role in monocot pathogens is less defined. Pg1 and xyr1 genes of the wheat pathogen Fusarium graminearum encode the main PG and the major regulator of xylanase production, respectively. Single- and double-disrupted mutants for these genes were obtained to assess their contribution to fungal infection. Compared with wild-type strain, the ∆pg mutant showed a nearly abolished PG activity, slight reduced virulence on soybean seedlings, but no significant difference in disease symptoms on wheat spikes; the ∆xyr mutant was strongly reduced in xylanase activity and moderately reduced in cellulase activity but was as virulent as wild type on both soybean and wheat plants. Consequently, the ΔpgΔxyr double mutant was impaired in xylanase, PG, and cellulase activities but, differently from single mutants, was significantly reduced in virulence on both plants. These findings demonstrate that the concurrent presence of PG, xylanase, and cellulase activities is necessary for full virulence. The observation that the uronides released from wheat cell wall after a F. graminearum PG treatment were largely increased by the fungal xylanases suggests that these enzymes act synergistically in deconstructing the plant cell wall.

  18. Proteomic Investigation of Rhizoctonia solani AG 4 Identifies Secretome and Mycelial Proteins with Roles in Plant Cell Wall Degradation and Virulence.

    PubMed

    Lakshman, Dilip K; Roberts, Daniel P; Garrett, Wesley M; Natarajan, Savithiry S; Darwish, Omar; Alkharouf, Nadim; Pain, Arnab; Khan, Farooq; Jambhulkar, Prashant P; Mitra, Amitava

    2016-04-20

    Rhizoctonia solani AG 4 is a soilborne necrotrophic fungal plant pathogen that causes economically important diseases on agronomic crops worldwide. This study used a proteomics approach to characterize both intracellular proteins and the secretome of R. solani AG 4 isolate Rs23A under several growth conditions, the secretome being highly important in pathogenesis. From over 500 total secretome and soluble intracellular protein spots from 2-D gels, 457 protein spots were analyzed and 318 proteins positively matched with fungal proteins of known function by comparison with available R. solani genome databases specific for anastomosis groups 1-IA, 1-IB, and 3. These proteins were categorized to possible cellular locations and functional groups and for some proteins their putative roles in plant cell wall degradation and virulence. The majority of the secreted proteins were grouped to extracellular regions and contain hydrolase activity.

  19. Processing technologies and cell wall degrading enzymes to improve nutritional value of dried distillers grain with solubles for animal feed: an in vitro digestion study.

    PubMed

    de Vries, Sonja; Pustjens, Annemieke M; Kabel, Mirjam A; Salazar-Villanea, Sergio; Hendriks, Wouter H; Gerrits, Walter J J

    2013-09-18

    Currently, the use of maize dried distillers grain with solubles (DDGS) as protein source in animal feed is limited by the inferior protein quality and high levels of non-starch polysaccharides (NSP). Processing technologies and enzymes that increase NSP degradability might improve digestive utilization of DDGS, enhancing its potential as a source of nutrients for animals. The effects of various combinations of processing technologies and commercial enzyme mixtures on in vitro digestion and subsequent fermentation of DDGS were tested. Wet-milling, extrusion, and mild hydrothermal acid treatment increased in vitro protein digestion but had no effect on NSP. Severe hydrothermal acid treatments, however, effectively solubilized NSP (48-78%). Addition of enzymes did not affect NSP solubilization in unprocessed or processed DDGS. Although the cell wall structure of DDGS seems to be resistant to most milder processing technologies, in vitro digestion of DDGS can be effectively increased by severe hydrothermal acid treatments.

  20. Tanjore: Mystical Painting of India

    ERIC Educational Resources Information Center

    Henn, Cynthia A.

    2004-01-01

    Tanjore (or Thanjavur or Thanlavoor) paintings are one of the most popular traditional art forms in Southern India. These ornate religious paintings involve Hindu mythology. The paintings are noted for their adornment of gold and semiprecious stones such as rubies, emeralds, and pearls. Currently, the semiprecious stones are often substituted…

  1. High pressure paint gun injuries.

    PubMed

    Booth, C M

    1977-11-19

    Despite their use for the past 20 years the dangers of injuries from high pressure paint guns are not widely known. Two cases treated incorrectly through ignorance in our casualty department resulted in amputation of digits. Paint solvents are far moe damaging than paint of grease injection. All cases should be treated urgently by an experienced surgeon as fairly extensive surgery may be needed.

  2. Tanjore: Mystical Painting of India

    ERIC Educational Resources Information Center

    Henn, Cynthia A.

    2004-01-01

    Tanjore (or Thanjavur or Thanlavoor) paintings are one of the most popular traditional art forms in Southern India. These ornate religious paintings involve Hindu mythology. The paintings are noted for their adornment of gold and semiprecious stones such as rubies, emeralds, and pearls. Currently, the semiprecious stones are often substituted…

  3. Static-Suppressing Optical Paint

    NASA Technical Reports Server (NTRS)

    Birnbaum, M. M.; Metzler, E. C.; Cleland, E. L.

    1985-01-01

    Electrically conductive flat black paint adheres well to magnesium, aluminum, fiberglass, and other materials. Paint absorbs stray light in optical instruments while preventing buildup of electrostatic fields and arcing. Paint consists of primer and topcoat, both containing electricallyconductive carbon-black powder. Primer two-part epoxy base, and topcoat polyurethane base.

  4. Paint by Numbers Revived!

    ERIC Educational Resources Information Center

    Hahn, Nic

    2012-01-01

    Remember paint by numbers? This revived trend was a perfect solution to teaching geometric shapes to the author's first-grade students. Geometric shapes are identified and used in early elementary art classrooms, but this lesson gives students a deeper understanding of shape, encourages problem-solving, and makes a strong correlation between math…

  5. Artists Paint ... Fantasy

    ERIC Educational Resources Information Center

    Herberholz, Barbara

    2012-01-01

    When he painted a portrait of Holy Roman Emperor Rudolph II (1552-1612), Giuseppe Arcimboldo used his imagination, and portrayed him as "Vertumnus," the Roman god of vegetation and the seasons. It's fun to find the different fruits, vegetables and flowers he used: pea-pod eyelids, a gourd for the forehead. Court painters of the time usually…

  6. Stylized Silk Painting.

    ERIC Educational Resources Information Center

    Skophammer, Karen

    1998-01-01

    Presents an art activity inspired by a workshop "Surrounded by Silk" given by Susan Skvoe in which the students create silk paintings. Explains that the students first sketch their floral design on paper, trace the design on the silk's surface, and apply liquid dye for color. Provides an easier activity for younger students. (CMK)

  7. Artists Paint ... Fantasy

    ERIC Educational Resources Information Center

    Herberholz, Barbara

    2012-01-01

    When he painted a portrait of Holy Roman Emperor Rudolph II (1552-1612), Giuseppe Arcimboldo used his imagination, and portrayed him as "Vertumnus," the Roman god of vegetation and the seasons. It's fun to find the different fruits, vegetables and flowers he used: pea-pod eyelids, a gourd for the forehead. Court painters of the time usually…

  8. Children and Painting.

    ERIC Educational Resources Information Center

    Topal, Cathy Weisman

    This handbook demonstrates how studio art concepts may be broken down into their simplest level, thus, allowing preschool and elementary students to work with one particular concept and technique at a time. Teachers are encouraged to coordinate open-ended painting activities with major study units taking place in the classroom. The fourteen…

  9. Painting Patterns with Pixels.

    ERIC Educational Resources Information Center

    Yoerg, Kim

    2002-01-01

    Describes an art unit for middle school students where they created their own original pattern through the use of "ClarisWorks Paint." Discusses the procedure for the project and the evaluation used at the end of the unit. Emphasizes the importance of learning about computers. (CMK)

  10. Paint by Numbers Revived!

    ERIC Educational Resources Information Center

    Hahn, Nic

    2012-01-01

    Remember paint by numbers? This revived trend was a perfect solution to teaching geometric shapes to the author's first-grade students. Geometric shapes are identified and used in early elementary art classrooms, but this lesson gives students a deeper understanding of shape, encourages problem-solving, and makes a strong correlation between math…

  11. Painting Cloth with Crayons.

    ERIC Educational Resources Information Center

    Asch, Rosalie L.

    1979-01-01

    Painting cloth with crayons is suggested as a challenging art project, especially for students who have difficulty with the complex tools and processes typical of more advanced textile work. Instructions are given for creating decorative banners with this technique. One of seven articles in this issue on fiber arts. (Author/SJL)

  12. Improved Paint Removal Technique

    DTIC Science & Technology

    1978-04-25

    4 (Phenol)1: p1P4 ji:i Condition of Point Surface Condition of Paint: Surface 4 after 45 minutes ufter 25 minutes Ten~t Pronsidure No. I. on~ Tent ...the ,.I .- pit so high velume water flow can be used to flush the pit floor clean at I the end of each day. Installation of removable grating is also

  13. Production of cellulose- and xylan-degrading enzymes by a koji mold, aspergillus oryzae, and their contribution to the maceration of rice endosperm cell wall.

    PubMed

    Yamane, Yu-Ichi; Fujita, Jin; Shimizu, Ryu-Ichi; Hiyoshi, Akira; Fukuda, Hisashi; Kizaki, Yasuzo; Wakabayashi, Saburo

    2002-01-01

    The production of cellulose- (CEL), xylan- (XYL), and pectin-degrading enzymes (PEC) by a koji mold, Aspergillus oryzae, was studied, and their contributions to the maceration of the rice endosperm cell wall were investigated with regard to the utilization of available rice in the sake mash. The sake koji mold showed higher CEL and XYL productivities, whereas the miso and soy sauce koji molds showed higher PEC productivity. Statistical analyses indicated that CEL and XYL contribute predominantly and synergistically to the maceration of the rice endosperm cell wall. A. oryzae produced at least three kinds of CEL (Cel-1, 2, 3) and two kinds of XYL (Xyl-1, 2) when cultured in a wheat bran medium. In the solid-state culture, the production of Cel-3 and Xyl-2 was markedly stimulated by decreasing the moisture content of the solid substrate, although the production levels of Cel-1 and Xyl-1 were almost the same. These data suggest that the production of Cel-3 and Xyl-2 is strongly influenced by culture conditions, and that water activity is one of the dominant factors in the regulation of their production.

  14. Efficient degradation of methylene blue dye over tungsten trioxide/multi-walled carbon nanotube system as a novel photocatalyst

    NASA Astrophysics Data System (ADS)

    Dinari, Mohammad; Momeni, Mohamad Mohsen; Ahangarpour, Marzieh

    2016-10-01

    Combination of acid-functionalized multi-walled carbon nanotube/tungsten trioxide (MWCNT/WO3) with different MWCNT's weight percentages as visible light-induced photocatalysts for photodegradation of methylene blue (MB) dye was synthesized. These photocatalysts were characterized by Fourier transform infrared, X-ray diffraction, UV-Vis diffuse reflectance spectroscopy, field emission scanning electron microscopy and transmission electron microscopy techniques. Their photocatalytic activities were tested by using MB as a model compound. The results show that the MWCNT/WO3 hybrid nanostructures exhibit higher photocatalytic activity than pure WO3 or MWCNTs due to their higher absorption enhancement in visible light region and effective separation of electrons and holes. The stability of the hybrid was characterized through cyclic photocatalytic test.

  15. Interior building details of Building A, Room A101: painted wood ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior building details of Building A, Room A-101: painted wood staircase, wood handrails with metal brackets, plastered finished brick walls; westerly view - San Quentin State Prison, Building 22, Point San Quentin, San Quentin, Marin County, CA

  16. Binding of human serum albumin to single-walled carbon nanotubes activated neutrophils to increase production of hypochlorous acid, the oxidant capable of degrading nanotubes.

    PubMed

    Lu, Naihao; Li, Jiayu; Tian, Rong; Peng, Yi-Yuan

    2014-06-16

    Previous studies have shown that carboxylated single-walled carbon nanotubes (SWCNTs) can be catalytically biodegraded by hypochlorite (OCl-) and reactive radical intermediates of the human neutrophil enzyme myeloperoxidase (MPO). However, the importance of protein-SWCNT interactions in the biodegradation of SWCNTs was not stressed. Here, we used both experimental and theoretical approaches to investigate the interactions of SWCNTs with human serum albumin (HSA, one of the most abundant proteins in blood circulation) and found that the binding was involved in the electrostatic interactions of positively charged Arg residues of HSA with the carboxyls on the nanotubes, along with the π-π stacking interactions between SWCNTs and aromatic Tyr residues in HSA. Compared with SWCNTs, the binding of HSA could result in a reduced effect for OCl- (or the human MPO system)-induced SWCNTs degradation in vitro. However, the HSA-SWCNT interactions would enhance cellular uptake of nanotubes and stimulate MPO release and OCl- generation in neutrophils, thereby creating the conditions favorable for the degradation of the nanotubes. Upon zymosan stimulation, both SWCNTs and HSA-SWCNTs were significantly biodegraded in neutrophils, and the degree of biodegradation was more for HSA-SWCNTs under these relevant in vivo conditions. Our findings suggest that the binding of HSA may be an important determinant for MPO-mediated SWCNT biodegradation in human inflammatory cells and therefore shed light on the biomedical and biotechnological applications of safe carbon nanotubes by comprehensive preconsideration of their interactions with human serum proteins.

  17. The strawberry (Fragariaxananassa) fruit-specific rhamnogalacturonate lyase 1 (FaRGLyase1) gene encodes an enzyme involved in the degradation of cell-wall middle lamellae.

    PubMed

    Molina-Hidalgo, Francisco J; Franco, Antonio R; Villatoro, Carmen; Medina-Puche, Laura; Mercado, José A; Hidalgo, Miguel A; Monfort, Amparo; Caballero, José Luis; Muñoz-Blanco, Juan; Blanco-Portales, Rosario

    2013-04-01

    Pectins are essential components of primary plant cell walls and middle lamellae, and are related to the consistency of the fruit and its textural changes during ripening. In fact, strawberries become soft as the middle lamellae of cortical parenchyma cells are extensively degraded during ripening, leading to the observed short post-harvest shelf life. Using a custom-made oligonucleotide-based strawberry microarray platform, a putative rhamnogalacturonate lyase gene (FaRGlyase1) was identified. Bioinformatic analysis of the FaRGlyase1 sequence allowed the identification of a conserved rhamnogalacturonate lyase domain, which was also present in other putative RGlyase sequences deposited in the databases. Expression of FaRGlyase1 occurred mainly in the receptacle, concurrently with ripening, and it was positively regulated by abscisic acid and negatively by auxins. FaRGLyase1 gene expression was transiently silenced by injecting live Agrobacterium cells harbouring RNA interference constructs into fruit receptacles. Light and electron microscopy analyses of these transiently silenced fruits revealed that this gene is involved in the degradation of pectins present in the middle lamella region between parenchymatic cells. In addition, genetic linkage association analyses in a strawberry-segregating population showed that FaRGLyase1 is linked to a quantitative trait loci linkage group related to fruit hardness and firmness. The results showed that FaRGlyase1 could play an important role in the fruit ripening-related softening process that reduces strawberry firmness and post-harvest life.

  18. Testing painted wood : past practices at the Forest Products Laboratory and recommendations for future research

    Treesearch

    R. Sam Williams

    2009-01-01

    A brief history of paint research at the Forest Products Laboratory (FPL) in Madison, Wisconsin, sets the stage for a discussion of testing paint on wood and wood products. Tests include laboratory and outdoor tests, and I discuss them in terms of several degradation mechanisms (loss of gloss and fading, mildew growth, extractives bleed, and cracking, flaking, and...

  19. Nutritive values of corn, soybean meal, canola meal, and peas for broiler chickens as affected by a multicarbohydrase preparation of cell wall degrading enzymes.

    PubMed

    Meng, X; Slominski, B A

    2005-08-01

    The effect of a new multicarbohydrase supplement of cell wall degrading activities on the nutritive value of corn, soybean meal (SBM), canola meal (CM), and peas for broiler chickens was investigated. Four isoenergetic and isonitrogenous corn (69% corn), SBM (30% SBM, 59% corn), CM (30% CM, 54% corn), and pea (30% peas, 52% corn) diets, without or with enzyme supplementation, were formulated to meet NRC specifications for broiler chickens (except for AME and CP, which were at 95 and 92% of NRC requirements, respectively). The enzyme supplement supplied 1,000 U of xylanase, 400 U of glucanase, 1,000 U of pectinase, 120 U of cellulase, 280 U of mannanase, and 180 U of galactanase per kilogram of diet. Each diet was fed in a mash form to 9 replicate pens of 5 broilers from 5 to 18 d. When compared with the control treatment, enzyme addition to the corn diet improved (P < 0.05) feed-to-gain ratio, whereas the performance of birds fed the other 3 diets was not affected. An increase (P < 0.05) in total tract nonstarch polysaccharides (NSP) digestibility, ileal starch digestibility, and AMEn was observed in birds fed the enzyme-supplemented corn diet. An improvement (P < 0.05) in total tract NSP digestibility, ileal protein digestibility, and AMEn content with enzyme supplementation was observed for the SBM diet. However, nutrient digestibilities and AMEn of CM and pea diets were not affected (P > 0.05) by enzyme addition even though the NSP digestibilities increased significantly (P < 0.05). A significant increase (P < 0.05) in water-soluble NSP and a decrease (P < 0.05) in water-insoluble NSP concentration of ileal digesta was noted for birds fed all 4 enzyme-supplemented diets. It would appear from this study that the nutrient utilization of corn-SBM diet by broilers could be enhanced by using an appropriate multicarbohydrase enzyme supplement. The nutrient encapsulating effect of cell wall polysaccharides in SBM, CM, and peas may not be the only factor responsible for

  20. Degradation of flumequine in aqueous solution by persulfate activated with common methods and polyhydroquinone-coated magnetite/multi-walled carbon nanotubes catalysts.

    PubMed

    Feng, Mingbao; Qu, Ruijuan; Zhang, Xiaoling; Sun, Ping; Sui, Yunxia; Wang, Liansheng; Wang, Zunyao

    2015-11-15

    In recent years, flumequine (FLU) has been ubiquitously detected in surface waters and municipal wastewaters. In light of its potential negative impacts to aquatic species, growing concern has been arisen for the removal of this antibiotic from natural waters. In this study, the kinetics, degradation mechanisms and pathways of aqueous FLU by persulfate (PS) oxidation were systematically determined. Three common activation methods, including heat, Fe(2+) and Cu(2+), and a novel heterogeneous catalyst, namely, polyhydroquinone-coated magnetite/multi-walled carbon nanotubes (Fe3O4/MWCNTs/PHQ), were investigated to activate PS for FLU removal. It was found that these three common activators enhanced FLU degradation obviously, while several influencing factors, such as solution pH, inorganic ions (especially HCO3(-) at 5 mmol/L) and dissolved organic matter extracts, exerted their different effects on FLU removal. The catalysts were characterized, and an efficient catalytic degradation performance, high stability and excellent reusability were observed. The measured total organic carbon levels suggested that FLU can be effectively mineralized by using the catalysts. Radical mechanism was studied by combination of the quenching tests and electron paramagnetic resonance analysis. It was assumed that sulfate radicals predominated in the activation of PS with Fe3O4/MWCNTs/PHQ for FLU removal, while hydroxyl radicals also contributed to the catalytic oxidation process. In addition, a total of fifteen reaction intermediates of FLU were identified, from which two possible pathways were proposed involving hydroxylation, decarbonylation and ring opening. Overall, this study represented a systematical evaluation regarding the transformation process of FLU by PS, and showed that the heterogeneous catalysts can efficiently activate PS for FLU removal from the water environment.

  1. 18. LAUNCH CONTROL SUPPORT BUILDING. 'MISSILE ART' MURAL PAINTED ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. LAUNCH CONTROL SUPPORT BUILDING. 'MISSILE ART' MURAL PAINTED ON INTERIOR WALL OF ELEVATOR SHAFT. VIEW TO EAST. - Minuteman III ICBM Launch Control Facility November-1, 1.5 miles North of New Raymer & State Highway 14, New Raymer, Weld County, CO

  2. 38. Detail of a sign painted on the side of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    38. Detail of a sign painted on the side of a building. The structure has a timber lintle and a piece of wood attached to the wall above the windows, giving the impression of a string course. - Butte Historic District, Bounded by Copper, Arizona, Mercury & Continental Streets, Butte, Silver Bow County, MT

  3. Modelling rock wall permafrost degradation in the Mont Blanc massif from the LIA to the end of the 21st century

    NASA Astrophysics Data System (ADS)

    Magnin, Florence; Josnin, Jean-Yves; Ravanel, Ludovic; Pergaud, Julien; Pohl, Benjamin; Deline, Philip

    2017-08-01

    High alpine rock wall permafrost is extremely sensitive to climate change. Its degradation has a strong impact on landscape evolution and can trigger rockfalls constituting an increasing threat to socio-economical activities of highly frequented areas; quantitative understanding of permafrost evolution is crucial for such communities. This study investigates the long-term evolution of permafrost in three vertical cross sections of rock wall sites between 3160 and 4300 m above sea level in the Mont Blanc massif, from the Little Ice Age (LIA) steady-state conditions to 2100. Simulations are forced with air temperature time series, including two contrasted air temperature scenarios for the 21st century representing possible lower and upper boundaries of future climate change according to the most recent models and climate change scenarios. The 2-D finite element model accounts for heat conduction and latent heat transfers, and the outputs for the current period (2010-2015) are evaluated against borehole temperature measurements and an electrical resistivity transect: permafrost conditions are remarkably well represented. Over the past two decades, permafrost has disappeared on faces with a southerly aspect up to 3300 m a.s.l. and possibly higher. Warm permafrost (i.e. > - 2 °C) has extended up to 3300 and 3850 m a.s.l. in N and S-exposed faces respectively. During the 21st century, warm permafrost is likely to extend at least up to 4300 m a.s.l. on S-exposed rock walls and up to 3850 m a.s.l. depth on the N-exposed faces. In the most pessimistic case, permafrost will disappear on the S-exposed rock walls at a depth of up to 4300 m a.s.l., whereas warm permafrost will extend at a depth of the N faces up to 3850 m a.s.l., but possibly disappearing at such elevation under the influence of a close S face. The results are site specific and extrapolation to other sites is limited by the imbrication of local topographical and transient effects.

  4. Production of multifunctional chimaeric enzymes in plants: a promising approach for degrading plant cell wall from within.

    PubMed

    Fan, Zhanmin; Yuan, Ling

    2010-04-01

    Multifunctional chimaeric hydrolases can be created by covalently linking heterologous catalytic and functional domains in a single polypeptide. Previously, we have generated a number of chimaeric lignocellulosic hydrolases that contain two to five modules [Biotechnol Bioeng (2009) 102: 1045; Appl Environ Microbiol (2009) 75: 1754]. These chimaeras closely resemble the parental enzymes in kinetics and other enzymatic properties, and some exhibit improved synergy in degrading natural substrates when compared to mixtures of parental enzymes. In addition to the applications in fermentative enzyme production, the chimaeric genes can be used in the construction of a single plant transformation binary vector carrying several genes that encode a complete set of lignocellulosic hydrolase activities. The advantages of this approach include ease in vector construction and transformation, as well as downstream plant analysis and breeding. The hydrolases sequestered in biomass feedstock can potentially assist enzymatic pretreatment and sugar conversion. Here, we report the gene expression and functional characterization of a chimaeric hemicellulase in transgenic tobacco plants. T1 transgenic plants produced up to 19-mg active enzymes per gram of total-soluble leaf proteins. The results demonstrate the feasibility of producing multifunctional lignocellulosic hydrolases in plants. Key considerations in the design, construction and plant expression of the chimaeric genes are discussed.

  5. Reducer Selection When Doing Overall Paint Jobs Using Enamel Paints. Lesson Plan No. 1 of Auto Repair and Painting.

    ERIC Educational Resources Information Center

    Tyau, Layton M.

    This lesson, which is part of a high school course in auto body repair and painting, deals with selecting a reducer when doing overall paint jobs using enamel paints. Students are taught the general properties of different types of enamel paints and selection of the proper reducer for each type of paint, depending on the weather and the specific…

  6. Reducer Selection When Doing Overall Paint Jobs Using Enamel Paints. Lesson Plan No. 1 of Auto Repair and Painting.

    ERIC Educational Resources Information Center

    Tyau, Layton M.

    This lesson, which is part of a high school course in auto body repair and painting, deals with selecting a reducer when doing overall paint jobs using enamel paints. Students are taught the general properties of different types of enamel paints and selection of the proper reducer for each type of paint, depending on the weather and the specific…

  7. Perhydrolase-nanotube paint composites with sporicidal and antiviral activity.

    PubMed

    Grover, Navdeep; Douaisi, Marc P; Borkar, Indrakant V; Lee, Lillian; Dinu, Cerasela Zoica; Kane, Ravi S; Dordick, Jonathan S

    2013-10-01

    AcT (perhydrolase) containing paint composites were prepared leading to broad-spectrum decontamination. AcT was immobilized onto multi-walled carbon nanotubes (MWNTs) and then incorporated into latex-based paints to form catalytic coatings. These AcT-based paint composites showed a 6-log reduction in the viability of spores of Bacillus cereus and Bacillus anthracis (Sterne) within 60 min. The paint composites also showed >4-log reduction in the titer of influenza virus (X-31) within 10 min (initially challenged with 10(7) PFU/mL). AcT-based paint composites were also tested using various perhydrolase acyl donor substrates, including propylene glycol diacetate (PGD), glyceryl triacetate, and ethyl acetate, with PGD observed to be the best among the substrates tested for generation of peracetic acid and killing of bacillus spores. The operational stability of paint composites was also studied at different relative humidities and temperatures to simulate real-life operation.

  8. Optimization of solar-selective paint coatings

    NASA Astrophysics Data System (ADS)

    McChesney, M. A.; Zimmer, P. B.; Lin, R. J. H.

    1982-06-01

    The objective was the development of low-cost, high-performance, solar-selective paint coatings for solar flat-plate collector (FPC) use and passive thermal wall application. Thickness-sensitive selective paint coating development was intended to demonstrate large scale producibility. Thickness-insensitive selective paint (TISP) coating development was intended to develop and optimize the coating for passive solar systems and FPC applications. Low-cost, high-performance TSSP coatings and processes were developed to demonstrate large-scale producibility and meet all program goals. Dip, spray, roll, laminating and gravure processes were investigated and used to produce final samples. High-speed gravure coating was selected as the most promising process for solar foil fabrication. Development and optimization of TISP coatings was not completely successful. A variation in reflective metal pigment was suspected of being the primary problem, although other variables may have contributed. Consistent repeating of optical properties of these coatings achieved on the previous program was not achieved.

  9. Degradation process of lead chromate in paintings by Vincent van Gogh studied by means of spectromicroscopic methods. 4. Artificial aging of model samples of co-precipitates of lead chromate and lead sulfate.

    PubMed

    Monico, Letizia; Janssens, Koen; Miliani, Costanza; Van der Snickt, Geert; Brunetti, Brunetto Giovanni; Cestelli Guidi, Mariangela; Radepont, Marie; Cotte, Marine

    2013-01-15

    Previous investigations about the darkening of chrome yellow pigments revealed that this form of alteration is attributable to a reduction of the original Cr(VI) to Cr(III), and that the presence of sulfur-containing compounds, most often sulfates, plays a key role during this process. We recently demonstrated that different crystal forms of chrome yellow pigments (PbCrO(4) and PbCr(1-x)S(x)O(4)) are present in paintings by Vincent van Gogh. In the present work, we show how both the chemical composition and the crystalline structure of lead chromate-based pigments influence their stability. For this purpose, oil model samples made with in-house synthesized powders of PbCrO(4) and PbCr(1-x)S(x)O(4) were artificially aged and characterized. We observed a profound darkening only for those paint models made with PbCr(1-x)S(x)O(4), rich in SO(4)(2-) (x ≥ 0.4), and orthorhombic phases (>30 wt %). Cr and S K-edge micro X-ray absorption near edge structure investigations revealed in an unequivocal manner the formation of up to about 60% of Cr(III)-species in the outer layer of the most altered samples; conversely, independent of the paint models' chemical composition, no change in the S-oxidation state was observed. Analyses employing UV-visible diffuse reflectance and Fourier transform infrared spectroscopy were performed on unaged and aged model samples in order to obtain additional information on the physicochemical changes induced by the aging treatment.

  10. 46 CFR 72.05-45 - Paint.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Paint. 72.05-45 Section 72.05-45 Shipping COAST GUARD... Protection § 72.05-45 Paint. (a) An excessive number of coats of paint will be discouraged unless noncombustible paint is used. (b) Nitrocellulose or other highly flammable or noxious fume-producing paints...

  11. 29 CFR 1915.35 - Painting.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false Painting. 1915.35 Section 1915.35 Labor Regulations... Painting. (a) Paints mixed with toxic vehicles or solvents. (1) When paints mixed with toxic vehicles or.... (2) Where brush application of paints with toxic solvents is done in confined spaces or in...

  12. 29 CFR 1915.35 - Painting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Painting. 1915.35 Section 1915.35 Labor Regulations... Painting. (a) Paints mixed with toxic vehicles or solvents. (1) When paints mixed with toxic vehicles or.... (2) Where brush application of paints with toxic solvents is done in confined spaces or in...

  13. 46 CFR 72.05-45 - Paint.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Paint. 72.05-45 Section 72.05-45 Shipping COAST GUARD... Protection § 72.05-45 Paint. (a) An excessive number of coats of paint will be discouraged unless noncombustible paint is used. (b) Nitrocellulose or other highly flammable or noxious fume-producing paints...

  14. 46 CFR 72.05-45 - Paint.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 3 2013-10-01 2013-10-01 false Paint. 72.05-45 Section 72.05-45 Shipping COAST GUARD... Protection § 72.05-45 Paint. (a) An excessive number of coats of paint will be discouraged unless noncombustible paint is used. (b) Nitrocellulose or other highly flammable or noxious fume-producing paints...

  15. 46 CFR 72.05-45 - Paint.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 3 2014-10-01 2014-10-01 false Paint. 72.05-45 Section 72.05-45 Shipping COAST GUARD... Protection § 72.05-45 Paint. (a) An excessive number of coats of paint will be discouraged unless noncombustible paint is used. (b) Nitrocellulose or other highly flammable or noxious fume-producing paints...

  16. 29 CFR 1915.35 - Painting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false Painting. 1915.35 Section 1915.35 Labor Regulations... Painting. (a) Paints mixed with toxic vehicles or solvents. (1) When paints mixed with toxic vehicles or.... (2) Where brush application of paints with toxic solvents is done in confined spaces or in...

  17. 29 CFR 1915.35 - Painting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Painting. 1915.35 Section 1915.35 Labor Regulations... Painting. (a) Paints mixed with toxic vehicles or solvents. (1) When paints mixed with toxic vehicles or.... (2) Where brush application of paints with toxic solvents is done in confined spaces or in...

  18. 46 CFR 72.05-45 - Paint.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 3 2011-10-01 2011-10-01 false Paint. 72.05-45 Section 72.05-45 Shipping COAST GUARD... Protection § 72.05-45 Paint. (a) An excessive number of coats of paint will be discouraged unless noncombustible paint is used. (b) Nitrocellulose or other highly flammable or noxious fume-producing paints...

  19. Biodeterioration of Pompeian mural paintings: fungal colonization favoured by the presence of volcanic material residues.

    PubMed

    Veneranda, Marco; Prieto-Taboada, Nagore; de Vallejuelo, Silvia Fdez-Ortiz; Maguregui, Maite; Morillas, Hector; Marcaida, Iker; Castro, Kepa; Madariaga, Juan Manuel; Osanna, Massimo

    2017-07-05

    This work was focused on the study of the biodegradation processes jeopardizing a mural painting conserved in the basement of Ariadne House (archaeological site of Pompeii, Italy). The fresco stood out for its peculiar state of preservation: the upper part, recovered in 1988, was just barely colonized by microorganisms. On the contrary, the lower part (excavated in 2005) was almost completely covered by extensive biological patinas. The genomic characterization carried out by polymerase chain reaction (PCR) highlighted the presence of seven different fungi strains on the mural surface. Beside, in situ and laboratory analyses were performed with the purpose of identifying the causes of the heterogeneous spatial distribution of the biopatinas. The in situ Raman spectroscopy and energy dispersive X-ray fluorescence (ED-XRF) spectroscopy measurements excluded any link between the heterogeneous colonization and the original materials present in the wall. On the other side, X-ray diffraction (XRD) and scanning electron microscopy (SEM) on microsamples proved the presence of a thin volcanic material layer overlying the lower part of the fresco. Considering that most of the biofilms of the studied mural painting only growth over these residues, it was confirmed the role of volcanic material as a suitable support for biological colonization. Thanks to the obtained results, this research helped to understand more in depth an important degradation pathway threatening the artworks from one of the most important archaeological sites in the world.

  20. High pressure paint gun injuries.

    PubMed Central

    Booth, C M

    1977-01-01

    Despite their use for the past 20 years the dangers of injuries from high pressure paint guns are not widely known. Two cases treated incorrectly through ignorance in our casualty department resulted in amputation of digits. Paint solvents are far moe damaging than paint of grease injection. All cases should be treated urgently by an experienced surgeon as fairly extensive surgery may be needed. Images FIG 1 FIG 2 FIG 3 FIG 4 PMID:589172

  1. Marine pollution from antifouling paint particles.

    PubMed

    Turner, Andrew

    2010-02-01

    Antifouling paint particles (APP) are generated during the maintenance of boats and are shed from abandoned structures and grounded ships. Although they afford a highly visible, colourful reflection of contamination in the vicinity of the source, little systematic study has been undertaken regarding the distribution, composition and effects of APP in the wider marine environment. This paper reviews the state of knowledge in respect of APP, with particular emphasis on those generated by recreational boatyards. The likely biogeochemical pathways of the biocidal and non-biocidal metals in current use (mainly Cu and Zn) are addressed in light of recent research and an understanding of the more general behaviour of contaminants in marine systems. Analyses of paint fragment composites from recreational facilities in the UK reveal chemical compositions that are similar to those representing the net signal of the original formulations; significantly, dry weight concentrations of Cu and Zn of up to about 35% and 15%, respectively, are observed and, relative to ambient dusts and sediment, elevated concentrations of other trace metals, like Ba, Cd, Cr, Ni, Pb and Sn, occur. These metals leach more rapidly from APP than a painted surface due to the greater surface area of pigments and additives exposed to the aqueous medium. In suspension, APP are subject to greater and more rapid environmental variation (e.g. salinity, pH, dissolved oxygen) than painted hulls, while settled APP represent an important source of persistent and degradable biocides to poorly circulating environments. Through diffusion and abrasion, high concentrations of contaminants are predicted in interstitial waters that may be accumulated directly by benthic invertebrates. Animals that feed non-selectively and that are exposed to or ingest paint-contaminated sediment are able to accelerate the leaching, deposition and burial of biocides and other substances, and represent an alternative vehicle for

  2. Search for cell-wall-degrading enzymes of world-wide rice grains by PCR and their effects on the palatability of rice.

    PubMed

    Nakamura, Sumiko; Machida, Keisuke; Ohtsubo, Ken'ichi

    2012-01-01

    Such rice cultivars as Japonica, Japonica-Indica hybrid, Javanica and Indica, were evaluated for their main chemical components (amylose content and protein content), pasting property of rice flour (consistency), physical property of the cooked rice grains (adhesion, L3), and enzyme activities (cellulase and xylanase). The amylose content, cellulase activity and xylanase activity showed significant positive or negative correlation with the pasting property (consistency) of rice flour (r = 0.89, r = 0.58, r = 0.70, respectively) and with the physical property of the cooked rice grains (adhesion, L3: r = -0.51, r = -0.61, r = -0.71, respectively) at the level of 1%. Endogenous xylanase and cellulase played important roles to determine the texture of the cooked rice grains similarly to the amylose content. Part of the DNA sequences of the α-glucosidase gene differed among the Japonica, Japonica-Indica hybrid and Indica subspecies. We found discriminative DNA bands appearing by PCR, corresponding to 1,4-β-xylanase and endo-1,4-β-glucanase 13 in the case of Indica rice, Indica-Japonica hybrid rice, and Javanica rice (non-Japonica subspecies). The equation for estimating the physical property (adhesion) of cooked rice grains by PCR was improved by adding novel primers related to the cell-wall-degrading enzymes.

  3. The use of plant cell wall-degrading enzymes from newly isolated Penicillium ochrochloron Biourge for viscosity reduction in ethanol production with fresh sweet potato tubers as feedstock.

    PubMed

    Huang, Yuhong; Jin, Yanling; Shen, Weiliang; Fang, Yang; Zhang, Guohua; Zhao, Hai

    2014-01-01

    Penicillium ochrochloron Biourge, which was isolated from rotten sweet potato, can produce plant cell wall-degrading enzymes (PCWDEs) with high viscosity reducing capability for ethanol production using fresh sweet potato tubers as feedstock. The enzyme preparation was characterized by a broad enzyme spectrum including 13 kinds of enzymes with the activity to hydrolyze cellulose, hemicellulose, pectin, starch, and protein. The maximum viscosity-reducing capability was observed when the enzyme preparation was obtained after 5 days of fermentation using 20 g/L corncob as a sole carbon source, 4.5 g/L NH4 NO3 as a sole nitrogen source, and an initial medium pH of 6.5. The sweet potato mash treated with the enzyme preparation exhibited much higher fermentation efficiency (92.58%) compared with commercial cellulase (88.06%) and control (83.5%). The enzyme production was then scaled up to 0.5, 5, and 100 L, and the viscosity-reducing rates were found to be 85%, 90%, and 91%, respectively. Thus, P. ochrochloron Biourge displays potential viscosity-reducing capability for ethanol production.

  4. Noninvasive depth profiling of walls by portable nuclear magnetic resonance.

    PubMed

    Blümich, Bernhard; Haber, Agnes; Casanova, Federico; Del Federico, Eleonora; Boardman, Victoria; Wahl, Gerhard; Stilliano, Antonella; Isolani, Licio

    2010-08-01

    A compact and mobile single-sided (1)H NMR sensor, the NMR-MOUSE, has been employed in the nondestructive characterization of the layer structure of historic walls and wall paintings. Following laboratory tests on a model hidden fresco, paint and mortar layers were studied at Villa Palagione and the Seminario Vescovile di Sant' Andrea in Volterra, Italy. Different paint and mortar layers were identified, and further characterized by portable X-ray fluorescence spectroscopy where accessible. In the detached and restored fresco "La Madonna della Carcere" from the Fortezza Medicea in Volterra, paint and mortar layers were discriminated and differences in the moisture content of the adhesive that fixes the detached wall painting to its support were found in both restored and original sections. These investigations encourage the use of the portable and single-sided NMR technology for nondestructive studies of the layer structure and conservation state of historic walls.

  5. VAB Flag Painting

    NASA Image and Video Library

    2002-01-01

    On platforms suspended from the top of the 525-foot-high VAB, workers use rollers and brushes to repaint the NASA logo on the southeast side of the Vehicle Assembly Building. Known as the "meatball," the logo measures 110 feet by 132 feet, or about 12,300 square feet. The U.S. flag is also being repainted. The flag spans an area 209 feet by 110 feet, or about 23, 437 square feet. Each stripe is 9 feet wide and each star is 6 feet in diameter. The flag and logo were last painted in 1998, honoring NASA's 40th anniversary.

  6. MC Contracting, Paint, & Roofing, LLC Information Sheet

    EPA Pesticide Factsheets

    MC Contracting, Paint, & Roofing, LLC, d/b/a M.C. Painting & Contractor and M.C. Painting Group (the Company) is located in Philadelphia, Pennsylvania. The settlement involves renovation activities conducted at property constructed prior to 1978.

  7. Laser assisted graffiti paints removing

    NASA Astrophysics Data System (ADS)

    Novikov, B. Y.; Chikalev, Y. V.; Shakhno, E. A.

    2011-02-01

    It's hard to imagine a modern city view without some drawings and inscriptions, usually called "graffiti". Traditional cleaning methods do not suit modern requirements. Investigation of possibilities of laser assisted paints removing is described in this article. The conditions for removing different paints from different surfaces were defined.

  8. Laser assisted graffiti paints removing

    NASA Astrophysics Data System (ADS)

    Novikov, B. Y.; Chikalev, Y. V.; Shakhno, E. A.

    2010-07-01

    It's hard to imagine a modern city view without some drawings and inscriptions, usually called "graffiti". Traditional cleaning methods do not suit modern requirements. Investigation of possibilities of laser assisted paints removing is described in this article. The conditions for removing different paints from different surfaces were defined.

  9. Microscale radiocarbon dating of paintings

    NASA Astrophysics Data System (ADS)

    Hendriks, Laura; Hajdas, Irka; McIntyre, Cameron; Küffner, Markus; Scherrer, Nadim C.; Ferreira, Ester S. B.

    2016-03-01

    In this paper, radiocarbon dating of paintings using minimal sample sizes has been investigated, in an effort to address the problem of limited access to sample material in paintings. 14C analyses were conducted on signed and dated paintings from two Swiss artists of the twentieth century. The selected paintings dated from the 1930s and 1960s, provided the opportunity to evaluate the dating accuracy on paintings realized before and after 1950 AD when the 14C bomb peak was created, as a result of the nuclear tests conducted in the 1950/1960s. The work focused on the one hand on minimizing the size of the canvas sample required for accelerator mass spectrometer radiocarbon measurement on the gas ion source of the MICADAS and, on the other hand, on testing the possibility of dating the organic binder of the paint. Following careful characterization of the paint composition by X-ray fluorescence spectroscopy, Fourier transformed infrared spectroscopy, and Raman spectroscopy, paints containing no other carbon source than the natural organic binder were identified and dated.

  10. Delving Deeper: Painting the Pyramid

    ERIC Educational Resources Information Center

    Kribs-Zaleta, Christopher M.

    2006-01-01

    Painting the Cube is commonly used in middle and high school mathematical courses as a mathematically rich problem, wherein the exposed faces of the large cubes are painted after being assembled from small unit cubes. The problem perfectly combines algebraic as well as geometrical aspects and helps students to study and understand various linear,…

  11. Additive Transforms Paint into Insulation

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Tech Traders Inc. sought assistance developing low-cost, highly effective coatings and paints that created useful thermal reflectance and were safe and non-toxic. In cooperation with a group of engineers at Kennedy Space Center., Tech Traders created Insuladd, a powder additive made up of microscopic, inert gas-filled, ceramic microspheres that can be mixed into ordinary interior or exterior paint, allowing the paint to act like a layer of insulation. When the paint dries, this forms a radiant heat barrier, turning the ordinary house paint into heat-reflecting thermal paint. According to Tech Traders, the product works with all types of paints and coatings and will not change the coverage rate, application, or adhesion of the paint. Other useful applications include feed storage silos to help prevent feed spoilage, poultry hatcheries to reduce the summer heat and winter cold effects, and on military vehicles and ships. Tech Traders has continued its connection to the aerospace community by recently providing Lockheed Martin Corporation with one of its thermal products for use on the F-22 Raptor.

  12. Studying pigments on painted plaster in Minoan, Roman and early Byzantine Crete. A multi-analytical technique approach.

    PubMed

    Westlake, Polly; Siozos, Panayiotis; Philippidis, Aggelos; Apostolaki, Chryssa; Derham, Brendan; Terlixi, Agni; Perdikatsis, Vasilios; Jones, Richard; Anglos, Demetrios

    2012-02-01

    Wall paintings spanning two millennia of Cretan painting history and technology were analysed in an effort to determine similarities and evolutions of painting materials and technology. A multi-technique approach was employed that combined the use of (a) laser-induced breakdown spectroscopy (LIBS) and Raman microspectroscopy, based on mobile instrumentation, appropriate for rapid, routine-level object characterization, and (b) non-destructive X-ray diffractometry (XRD), performed directly on the wall painting fragment, which provides detailed information on the minerals constituting the paint. Elemental analysis data obtained through LIBS were compared with molecular and crystal structure information from Raman spectroscopy and XRD. Cross-sections from selected samples were also investigated by means of optical microscopy and scanning electron microscopy coupled to micro-probe analysis and X-ray mapping that enabled identification of several mineral components of the paint confirming the results of the XRD analysis. In parallel, replica wall paintings, created with known pigments and binding media for reference purposes, were examined with optical microscopy and stain tested for organic materials. The overall study shows that the LIBS and Raman techniques offer key advantages, such as instrument mobility and speed of data collection and interpretation that are particularly important when dealing with on-site investigations. Thus, they are capable of providing important compositional information in an effective manner that enables quick surveying of wall paintings and permit targeted sample selection for further analysis by advanced laboratory techniques.

  13. Interior building details of Building A, Room A002: plastered painted ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior building details of Building A, Room A-002: plastered painted west brick wall, four light double-hung wood window with brick arch lintel, east plastered wall (could be granite), wood ceiling; northerly view - San Quentin State Prison, Building 22, Point San Quentin, San Quentin, Marin County, CA

  14. Short-term treatment with cell wall degrading enzymes increases the activity of the inositol phospholipid kinases and the vanadate-sensitive ATPase of carrot cells.

    PubMed

    Chen, Q; Boss, W F

    1990-12-01

    Treating carrot (Daucus carota L.) suspension culture cells with a mixture of cell wall degrading enzymes, Driselase, resulted in an increase in the percentage of [(3)H]phosphatidylinositol bisphosphate. Analysis of the lipid kinase activities in the isolated plasma membranes after whole cell treatment indicated that treatment with Driselase (2% weight/volume; the equivalent of 340 units per milliliter of hemicellulase and 400 units per milliliter of cellulase activity) or treatment with hemicellulase (31.7% weight/volume, 20.7 units per milliliter) resulted in an increase in the inositol phospholipid kinase activity. However, treatment with cellulase alone had no effect at 0.5% (weight/volume, 17.2 units per milliliter) or inhibited the kinase activity at 1% (weight/volume, 34.4 units per milliliter). The active stimulus in Driselase was heat sensitive. The plasma membrane vanadate-sensitive ATPase activity also increased when the cells were treated with Driselase. A time course study indicated that both the inositol phospholipid kinases and the plasma membrane vanadate-sensitive ATPase responded to as little as 5 seconds of treatment with 2% Driselase. However, at the lowest concentration of Driselase (0.04%, weight/volume) that resulted in an increase in inositol phospholipid kinase activity, the ATPase activity was not affected. Because inositol phospholipids have been shown to activate the vanadate-sensitive ATPase from plants (AR Memon, Q Chen, WF Boss [1989] Biochem Biophys Res Commun 162: 1295-1301), a stimulus-response pathway involving both the inositol phospholipid kinases and the plasma membrane vanadate-sensitive ATPase activity is discussed.

  15. Short-Term Treatment with Cell Wall Degrading Enzymes Increases the Activity of the Inositol Phospholipid Kinases and the Vanadate-Sensitive ATPase of Carrot Cells 1

    PubMed Central

    Chen, Qiuyun; Boss, Wendy F.

    1990-01-01

    Treating carrot (Daucus carota L.) suspension culture cells with a mixture of cell wall degrading enzymes, Driselase, resulted in an increase in the percentage of [3H]phosphatidylinositol bisphosphate. Analysis of the lipid kinase activities in the isolated plasma membranes after whole cell treatment indicated that treatment with Driselase (2% weight/volume; the equivalent of 340 units per milliliter of hemicellulase and 400 units per milliliter of cellulase activity) or treatment with hemicellulase (31.7% weight/volume, 20.7 units per milliliter) resulted in an increase in the inositol phospholipid kinase activity. However, treatment with cellulase alone had no effect at 0.5% (weight/volume, 17.2 units per milliliter) or inhibited the kinase activity at 1% (weight/volume, 34.4 units per milliliter). The active stimulus in Driselase was heat sensitive. The plasma membrane vanadate-sensitive ATPase activity also increased when the cells were treated with Driselase. A time course study indicated that both the inositol phospholipid kinases and the plasma membrane vanadate-sensitive ATPase responded to as little as 5 seconds of treatment with 2% Driselase. However, at the lowest concentration of Driselase (0.04%, weight/volume) that resulted in an increase in inositol phospholipid kinase activity, the ATPase activity was not affected. Because inositol phospholipids have been shown to activate the vanadate-sensitive ATPase from plants (AR Memon, Q Chen, WF Boss [1989] Biochem Biophys Res Commun 162: 1295-1301), a stimulus-response pathway involving both the inositol phospholipid kinases and the plasma membrane vanadate-sensitive ATPase activity is discussed. Images Figure 2 Figure 6 PMID:16667922

  16. Paint by Particle

    NASA Image and Video Library

    2017-09-27

    NASA models and supercomputing have created a colorful new view of aerosol movement. Satellites, balloon-borne instruments and ground-based devices make 30 million observations of the atmosphere each day. Yet these measurements still give an incomplete picture of the complex interactions within the membrane surrounding Earth. Enter climate models. Through mathematical experiments, modelers can move Earth forward or backward in time to create a dynamic portrait of the planet. Researchers from NASA Goddard’s Global Modeling and Assimilation Office recently ran a simulation of the atmosphere that captured how winds whip aerosols around the world. Such simulations allow scientists to better understand how these tiny particulates travel in the atmosphere and influence weather and climate. In the visualization below, covering August 2006 to April 2007, watch as dust and sea salt swirl inside cyclones, carbon bursts from fires, sulfate streams from volcanoes—and see how these aerosols paint the modeled world. Credit: NASA/Goddard Space Flight Center

  17. The painted shoes

    PubMed Central

    Noronha, Natália; Rosa Alexandre, André; Cavaca Santos, Joana; Rodrigues, Fernanda

    2015-01-01

    A previously well 4-year-old boy presented to the emergency room with progressive cyanosis, pallor and vomiting over the last 5 h. Oxygen saturation on pulse oximetry was 87–89% despite 9 L/min of supplemental oxygen. He was tachypnoeic and had a systolic heart murmur, with no other findings on clinical examination. In his medical history, there was record of a restrictive atrial septal defect, with a normal echocardiogram from 3 years before. He had no relevant family history. His shoes appeared to have been recently painted, which raised the suspicion of methaemoglobinaemia, presumptively caused by aniline-containing shoe dye. The shoes were removed promptly and his feet washed profusely. After confirming the diagnosis, methylene blue was started. The level of methaemoglobin decreased rapidly and the boy made a full recovery. PMID:26338243

  18. The painted shoes.

    PubMed

    Noronha, Natália; Rosa Alexandre, André; Cavaca Santos, Joana; Rodrigues, Fernanda

    2015-09-03

    A previously well 4-year-old boy presented to the emergency room with progressive cyanosis, pallor and vomiting over the last 5 h. Oxygen saturation on pulse oximetry was 87-89% despite 9 L/min of supplemental oxygen. He was tachypnoeic and had a systolic heart murmur, with no other findings on clinical examination. In his medical history, there was record of a restrictive atrial septal defect, with a normal echocardiogram from 3 years before. He had no relevant family history. His shoes appeared to have been recently painted, which raised the suspicion of methaemoglobinaemia, presumptively caused by aniline-containing shoe dye. The shoes were removed promptly and his feet washed profusely. After confirming the diagnosis, methylene blue was started. The level of methaemoglobin decreased rapidly and the boy made a full recovery.

  19. A comparative analysis of glove permeation resistance to paint stripping formulations.

    PubMed

    Stull, Jeffrey O; Thomas, Richard W; James, Lawrence E

    2002-01-01

    Although there is a wide variety of work gloves available to users of commercial paint stripping products, there are no published studies examining which type of gloves provide the best protection. To address this need, a multiphase study was undertaken to evaluate how several types of gloves resist multichemical-based paint stripping formulations. Due to the wide range of commercial paint stripping formulations available, seven categories of surrogate paint stripper formulations were created to evaluate glove performance initially. Twenty different glove types were identified for initial evaluation. Degradation resistance screening was carried out for each glove style and paint stripping formulation. Screening results were used to identify those glove styles least affected by the surrogate paint strippers. Those gloves were then evaluated for their resistance to permeation using continuous contact testing based on ASTM Test Method F 739. Glove styles showing extensive permeation with early breakthrough were then evaluated to see how they performed with only intermittent contact with the surrogate paint strippers using a modified form of ASTM Test Method F 1383. These results were used to select glove styles to be tested using commercially available paint stripping products. Gloves made of plastic laminate and butyl rubber were the most effective against the majority of paint strippers. More glove styles resisted permeation by N-methylpyrrolidone and dibasic ester-based paint strippers than conventional solvent products such as methylene chloride, methanol, isopropanol, acetone, and toluene. The study also found that decreased contact time caused relatively little change in permeation resistance and that the surrogate paint stripper data did not always accurately predict resistance to the commercial paint stripper formulations.

  20. Application of Pressure Sensitive Paint in Hypersonic Flows

    NASA Technical Reports Server (NTRS)

    Jules, Kenol; Carbonaro, Mario; Zemsch, Stephan

    1995-01-01

    It is well known in the aerodynamic field that pressure distribution measurement over the surface of an aircraft model is a problem in experimental aerodynamics. For one thing, a continuous pressure map can not be obtained with the current experimental methods since they are discrete. Therefore, interpolation or CFD methods must be used for a more complete picture of the phenomenon under study. For this study, a new technique was investigated which would provide a continuous pressure distribution over the surface under consideration. The new method is pressure sensitive paint. When pressure sensitive paint is applied to an aerodynamic surface and placed in an operating wind-tunnel under appropriate lighting, the molecules luminesce as a function of the local pressure of oxygen over the surface of interest during aerodynamic flow. The resulting image will be brightest in the areas of low pressure (low oxygen concentration), and less intense in the areas of high pressure (where oxygen is most abundant on the surface). The objective of this investigation was to use pressure sensitive paint samples from McDonnell Douglas (MDD) for calibration purpose in order to assess the response of the paint under appropriate lighting and to use the samples over a flat plate/conical fin mounted at 75 degrees from the center of the plate in order to study the shock/boundary layer interaction at Mach 6 in the Von Karman wind-tunnel. From the result obtained it was concluded that temperature significantly affects the response of the paint and should be given the uppermost attention in the case of hypersonic flows. Also, it was found that past a certain temperature threshold, the paint intensity degradation became irreversible. The comparison between the pressure tap measurement and the pressure sensitive paint showed the right trend. However, there exists a shift when it comes to the actual value. Therefore, further investigation is under way to find the cause of the shift.

  1. Electrically Conductive Paints for Satellites

    NASA Technical Reports Server (NTRS)

    Gilligan, J. E.; Wolf, R. E.; Ray, C.

    1977-01-01

    A program was conducted to develop and test electrically conductive paint coatings for spacecraft. A wide variety of organic and inorganic coatings were formulated using conductive binders, conductive pigments, and similar approaches. Z-93, IITRI's standard specification inorganic thermal control coating, exhibits good electrical properties and is a very space-stable coating system. Several coatings based on a conductive pigment (antimony-doped tin oxide) in silicone and silicate binders offer considerable promise. Paint systems using commercially available conductive polymers also appear to be of interest, but will require substantial development. Evaluations were made based on electrical conductivity, paint physical properties, and the stability of spectral reflectance in space environment testing.

  2. 7 CFR 3201.106 - Paint removers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Paint removers. 3201.106 Section 3201.106 Agriculture... Items § 3201.106 Paint removers. (a) Definition. Products formulated to loosen and remove paint from painted surfaces. (b) Minimum biobased content. The Federal preferred procurement product must have...

  3. Technology Demonstration of Membrane Chemical Strippers for Removal of Lead-Based Paint on Plaster

    DTIC Science & Technology

    2003-12-01

    plaster and drywall . The technology is applicable to the removal of all types of architectural coatings. The target contaminants are lead compounds used...total lead analysis in ac- cordance with EPA 600/R-93/200M-P (Total Metals in Paint Chips, Sonication ) and analyzed in accordance with EPA 6010B (ICP...paint removal methods. Of these seven methods three are not applicable to interior wall sur- faces such as plaster and drywall . HEPA vacuum blasting and

  4. KSC volunteers help paint Baxley Manor as part of Days of Caring '99

    NASA Technical Reports Server (NTRS)

    1999-01-01

    A volunteer for Days of Caring '99 prepares a light fixture before painting the walls in the hallway at Baxley Manor, an apartment building for senior citizens on Merritt Island. Coordinated by the KSC Community Relations Council, Days of Caring provides an opportunity for employees to volunteer their services in projects such as painting, planting flowers, reading to school children, and more. Organizations accepting volunteers include The Embers, Yellow Umbrella, Serene Harbor, Domestic Violence Program, the YMCA of Brevard County, and others.

  5. KSC volunteers help paint Baxley Manor as part of Days of Caring '99

    NASA Technical Reports Server (NTRS)

    1999-01-01

    A volunteer for Days of Caring '99 prepares a light fixture before painting the walls in the hallway at Baxley Manor, an apartment building for senior citizens on Merritt Island. Coordinated by the KSC Community Relations Council, Days of Caring provides an opportunity for employees to volunteer their services in projects such as painting, planting flowers, reading to school children, and more. Organizations accepting volunteers include The Embers, Yellow Umbrella, Serene Harbor, Domestic Violence Program, the YMCA of Brevard County, and others.

  6. Acute effect of indoor exposure to paint containing bis(tributyltin) oxide--Wisconsin, 1991

    SciTech Connect

    Not Available

    1991-05-03

    In January 1991, a woman in Wisconsin contacted her local public health department to report that she and her two children had become ill after her landlord painted the walls and ceilings of two rooms of her apartment. Reported symptoms included a burning sensation in the nose and forehead, headache, nose bleed, cough, loss of appetite, nausea, and vomiting. The woman, who was in the third trimester of pregnancy, also complained of a persistent odor from the paint and provided an empty bottle of a paint additive used for mildew control. The label indicated that this product contained 25% bis(tributyltin) oxide (TBTO) as its only active ingredient.

  7. Studying Landforms through Landscape Painting.

    ERIC Educational Resources Information Center

    Glenn, William H.

    1981-01-01

    Using three specific works of art, the author demonstrates how a study of selected landscape paintings can be integrated into units on landforms in secondary school earth science and general science courses. (Author/SJL)

  8. Solar-absorber-selective paint research

    NASA Astrophysics Data System (ADS)

    Moore, S. W.

    1982-01-01

    Research and development on thickness-sensitive and thickness-insensitive solar paints are discussed. The thickness-sensitive paints include reverse roll coated, gravure printed, and spray coated paints. The coating methods and optical properties of the thickness-sensitive paints are discussed. The thickness-insensitive solar paints include a low emittance flake such as aluminum-flake, and pigment. Durability tests are discussed, including accelerated weathering and humidity durability tests, for the thickness-sensitive coatings.

  9. Solar-absorber-selective paint research

    SciTech Connect

    Moore, S.W.

    1982-01-01

    Research and development on thickness-sensitive and thickness-insensitive solar paints are discussed. The thickness-sensitive paints include reverse roll coated, gravure printed, and spray coated paints. The coating methods and optical properties of the thickness-sensitive paints are discussed. The thickness-insensitive solar paints include a low emittance flake such as aluminium-flake, and pigment. Durability tests are discussed, including accelerated weathering and humidity durability tests, for the thickness-sensitive coatings. (LEW)

  10. Thermal characterization of intumescent fire retardant paints

    NASA Astrophysics Data System (ADS)

    Calabrese, L.; Bozzoli, F.; Bochicchio, G.; Tessadri, B.; Rainieri, S.; Pagliarini, G.

    2014-11-01

    Intumescent coatings are now the dominant passive fire protection materials used in industrial and commercial buildings. The coatings, which usually are composed of inorganic components contained in a polymer matrix, are inert at low temperatures and at higher temperatures, they expand and degrade to provide a charred layer of low conductivity materials. The charred layer, which acts as thermal barrier, will prevent heat transfer to underlying substrate. The thermal properties of intumescent paints are often unknown and difficult to be estimated since they vary significantly during the expansion process; for this reason the fire resistance validation of a commercial coatings is based on expensive, large-scale methods where each commercial coating-beam configuration has to be tested one by one. Adopting, instead, approaches based on a thermal modelling of the intumescent paint coating could provide an helpful tool to make easier the test procedure and to support the design of fire resistant structures as well. The present investigation is focused on the assessment of a methodology intended to the restoration of the equivalent thermal conductivity of the intumescent layer produced under the action of a cone calorimetric apparatus. The estimation procedure is based on the inverse heat conduction problem approach, where the temperature values measured at some locations inside the layer during the expansion process are used as input known data. The results point out that the equivalent thermal conductivity reached by the intumescent material at the end of the expansion process significantly depends on the temperature while the initial thickness of the paint does not seem to have much effect.

  11. Innovative Composite Wall System for Sheathing Masonry Walls

    SciTech Connect

    Wendt, Robert L.; Cavallo, James

    1997-09-25

    Existing Housing - Much of the older multifamily housing stock in the United States includes units in structures with uninsulated masonry walls. Included in this stock are two- and three-story walk-up apartments, larger apartment complexes, and public housing (both high- rise and townhouse). This older multifamily housing has seen years of heavy use that may have left the plaster wall marred or damaged. Long- term building settlement or movement may have cracked the plaster, sometimes severely. Moisture from invented kitchens and baths may have caused condensation on uninsulated exterior walls. At best this condensation has left stains on the paint or wallpaper. At worst it has supported mold and mildew growth, fouling the air and creating unhealthy living conditions. Deteriorating plaster and flaking paint also result from wet walls. The presence of flaking, lead-based paint in older (pre-1978) housing is a major public health concern. Children can suffer permanent mental handicaps and psychological disorders if they are subjected to elevated levels of lead, while adults can suffer hypertension and other maladies. Studies have found that, in some urban communities with older housing stocks, over 35% of children tested have elevated blood lead levels (Hastings, et al.: 1997). Nationally, nearly 22% of black, non-hispanic children living in pre-1946 housing were found to have elevated levels of lead in their blood (MWWR Article: February 21,1997). The deterioration of many of these walls is to the point that lead can freely enter the living space.

  12. Equidistant Intervals in Perspective Photographs and Paintings

    PubMed Central

    2016-01-01

    Human vision is extremely sensitive to equidistance of spatial intervals in the frontal plane. Thresholds for spatial equidistance have been extensively measured in bisecting tasks. Despite the vast number of studies, the informational basis for equidistance perception is unknown. There are three possible sources of information for spatial equidistance in pictures, namely, distances in the picture plane, in physical space, and visual space. For each source, equidistant intervals were computed for perspective photographs of walls and canals. Intervals appear equidistant if equidistance is defined in visual space. Equidistance was further investigated in paintings of perspective scenes. In appraisals of the perspective skill of painters, emphasis has been on accurate use of vanishing points. The current study investigated the skill of painters to depict equidistant intervals. Depicted rows of equidistant columns, tiles, tapestries, or trees were analyzed in 30 paintings and engravings. Computational analysis shows that from the middle ages until now, artists either represented equidistance in physical space or in a visual space of very limited depth. Among the painters and engravers who depict equidistance in a highly nonveridical visual space are renowned experts of linear perspective. PMID:27698983

  13. Distinctive expansion of gene families associated with plant cell wall degradation, secondary metabolism, and nutrient uptake in the genomes of grapevine trunk pathogens.

    PubMed

    Morales-Cruz, Abraham; Amrine, Katherine C H; Blanco-Ulate, Barbara; Lawrence, Daniel P; Travadon, Renaud; Rolshausen, Philippe E; Baumgartner, Kendra; Cantu, Dario

    2015-06-19

    Trunk diseases threaten the longevity and productivity of grapevines in all viticulture production systems. They are caused by distantly-related fungi that form chronic wood infections. Variation in wood-decay abilities and production of phytotoxic compounds are thought to contribute to their unique disease symptoms. We recently released the draft sequences of Eutypa lata, Neofusicoccum parvum and Togninia minima, causal agents of Eutypa dieback, Botryosphaeria dieback and Esca, respectively. In this work, we first expanded genomic resources to three important trunk pathogens, Diaporthe ampelina, Diplodia seriata, and Phaeomoniella chlamydospora, causal agents of Phomopsis dieback, Botryosphaeria dieback, and Esca, respectively. Then we integrated all currently-available information into a genome-wide comparative study to identify gene families potentially associated with host colonization and disease development. The integration of RNA-seq, comparative and ab initio approaches improved the protein-coding gene prediction in T. minima, whereas shotgun sequencing yielded nearly complete genome drafts of Dia. ampelina, Dip. seriata, and P. chlamydospora. The predicted proteomes of all sequenced trunk pathogens were annotated with a focus on functions likely associated with pathogenesis and virulence, namely (i) wood degradation, (ii) nutrient uptake, and (iii) toxin production. Specific patterns of gene family expansion were described using Computational Analysis of gene Family Evolution, which revealed lineage-specific evolution of distinct mechanisms of virulence, such as specific cell wall oxidative functions and secondary metabolic pathways in N. parvum, Dia. ampelina, and E. lata. Phylogenetically-informed principal component analysis revealed more similar repertoires of expanded functions among species that cause similar symptoms, which in some cases did not reflect phylogenetic relationships, thereby suggesting patterns of convergent evolution. This study

  14. Gating of Cl- currents in protoplasts from the marine alga Valonia utricularis depends on the transmembrane Cl- gradient and is affected by enzymatic cell wall degradation.

    PubMed

    Binder, K-A; Wegner, L H; Heidecker, M; Zimmermann, U

    2003-02-01

    The electrical properties of protoplasts of the turgor pressure-regulating giant marine alga Valonia utricularis were investigated by using the patch-clamp technique. In the whole-cell configuration, large inward currents were elicited by negative-going voltage pulses. The time-dependent component was predominantly carried by Cl-, as revealed by 'tail current' analysis. When experiments were performed on protoplasts directly after mechanical release from the 'mother cell', small outward currents were additionally observed at membrane voltages more positive than ECl-. These outward currents disappeared to a large extent after treatment of the protoplasts with a mixture of cell wall-degrading enzymes. Plots of the chord conductance versus the clamped membrane voltage revealed that enzymatic treatment affected the gating properties. By fitting Boltzmann distributions to the data, a midpoint potential of + 5 +/- 5 mV (n = 7) was obtained in symmetrical Cl- solutions for mechanically released protoplasts. In contrast, protoplasts treated additionally with enzymes exhibited a midpoint potential of -13 +/- 5 mV (n = 8). By varying the external and internal Cl- concentration, gating was also shown to depend on the Cl- gradient across the plasmalemma both in enzymatically treated and untreated protoplasts. Plotting of the midpoint potential against the Nernst potential of Cl- rendered a slope less than 1 (0.70 and 0.64, respectively) indicating that gating did not strictly depend on the electrochemical Cl- gradient. The voltage- and Cl--dependence as well as inhibition experiments with 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS) suggested that the Cl- conductance of the membrane is dominated by the Valonia Anion Channel 1 (VAC1) described by Heidecker, M., Wegner, L.H., Zimmermann, U. 1999: A patch-clamp study of ion channels in proto-plasts prepared from the marine alga Valonia utricularis. J. Membrane Biol. 172:235-247. The relevance of the findings for

  15. Transcriptomic Events Involved in Melon Mature-Fruit Abscission Comprise the Sequential Induction of Cell-Wall Degrading Genes Coupled to a Stimulation of Endo and Exocytosis

    PubMed Central

    Corbacho, Jorge; Romojaro, Félix; Pech, Jean-Claude; Latché, Alain; Gomez-Jimenez, Maria C.

    2013-01-01

    Background Mature-fruit abscission (MFA) in fleshy-fruit is a genetically controlled process with mechanisms that, contrary to immature-fruit abscission, has not been fully characterized. Here, we use pyrosequencing to characterize the transcriptomes of melon abscission zone (AZ) at three stages during AZ-cell separation in order to understand MFA control at an early stage of AZ-activation. Principal Findings The results show that by early induction of MFA, the melon AZ exhibits major gene induction, while by late induction of MFA, melon AZ shows major gene repression. Although some genes displayed similar regulation in both early and late induction of abscission, such as EXT1-EXT4, EGase1, IAA2, ERF1, AP2D15, FLC, MADS2, ERAF17, SAP5 and SCL13 genes, the majority had different expression patterns. This implies that time-specific events occur during MFA, and emphasizes the value of characterizing multiple time-specific abscission transcriptomes. Analysis of gene-expression from these AZs reveal that a sequential induction of cell-wall-degrading genes is associated with the upregulation of genes involved in endo and exocytosis, and a shift in plant-hormone metabolism and signaling genes during MFA. This is accompanied by transcriptional activity of small-GTPases and synthaxins together with tubulins, dynamins, V-type ATPases and kinesin-like proteins potentially involved in MFA signaling. Early events are potentially controlled by down-regulation of MADS-box, AP2/ERF and Aux/IAA transcription-factors, and up-regulation of homeobox, zinc finger, bZIP, and WRKY transcription-factors, while late events may be controlled by up-regulation of MYB transcription-factors. Significance Overall, the data provide a comprehensive view on MFA in fleshy-fruit, identifying candidate genes and pathways associated with early induction of MFA. Our comprehensive gene-expression profile will be very useful for elucidating gene regulatory networks of the MFA in fleshy-fruit. PMID

  16. Electrically conductive black optical paint

    NASA Technical Reports Server (NTRS)

    Birnbaum, M. M.; Metzler, E. C.; Cleland, E. L.

    1983-01-01

    An electrically conductive flat black paint has been developed for use on the Galileo spacecraft which will orbit Jupiter in the late 1980s. The paint, designed for equipment operating in high-energy radiation fields, has multipurpose functions. Its electrical conductivity keeps differential charging of the spacecraft external surfaces and equipment to a minimum, preventing the buildup of electrostatic fields and arcing. Its flat black aspect minimizes the effects of stray light and unwanted reflectances, when used in optical instruments and on sunshades. Its blackness is suitable, also, for thermal control, when the paint is put on spacecraft surfaces. The paint has good adherence properties, as measured by tape tests, when applied properly to a surface. The electrically conductive paint which was developed has the following characteristics: an electrical resistivity of 5 x 10 to the 7th ohms per square; a visual light total reflectance of approximately 5 percent; an infrared reflectance of 0.13 measured over a spectrum from 10 to the (-5.5) power to 0.001 meter; a solar absorptivity, alpha-s, of 0.93, and a thermal emissivity, epsilon, of 0.87, resulting in an alpha-s/epsilon of 1.07. The formula for making the paint and the process for applying it are described.

  17. Overview of paint removal methods

    NASA Astrophysics Data System (ADS)

    Foster, Terry

    1995-04-01

    With the introduction of strict environmental regulations governing the use and disposal of methylene chloride and phenols, major components of chemical paint strippers, there have been many new environmentally safe and effective methods of paint removal developed. The new methods developed for removing coatings from aircraft and aircraft components include: mechanical methods using abrasive media such as plastic, wheat starch, walnut shells, ice and dry ice, environmentally safe chemical strippers and paint softeners, and optical methods such as lasers and flash lamps. Each method has its advantages and disadvantages, and some have unique applications. For example, mechanical and abrasive methods can damage sensitive surfaces such as composite materials and strict control of blast parameters and conditions are required. Optical methods can be slow, leaving paint residues, and chemical methods may not remove all of the coating or require special coating formulations to be effective. As an introduction to environmentally safe and effective methods of paint removal, this paper is an overview of the various methods available. The purpose of this overview is to introduce the various paint removal methods available.

  18. Casting Light on the Darkening of Colors in Historical Paintings

    NASA Astrophysics Data System (ADS)

    Da Pieve, F.; Hogan, C.; Lamoen, D.; Verbeeck, J.; Vanmeert, F.; Radepont, M.; Cotte, M.; Janssens, K.; Gonze, X.; Van Tendeloo, G.

    2013-11-01

    The degradation of colors in historical paintings affects our cultural heritage in both museums and archeological sites. Despite intensive experimental studies, the origin of darkening of one of the most ancient pigments known to humankind, vermilion (α-HgS), remains unexplained. Here, by combining many-body theoretical spectroscopy and high-resolution microscopic x-ray diffraction, we clarify the composition of the damaged paint work and demonstrate possible physicochemical processes, induced by illumination and exposure to humidity and air, that cause photoactivation of the original pigment and the degradation of the secondary minerals. The results suggest a new path for the darkening process which was never considered by previous studies and prompt a critical examination of their findings.

  19. Single and multiplexed immunoassays for the chemiluminescent imaging detection of animal glues in historical paint cross-sections.

    PubMed

    Sciutto, G; Dolci, L S; Guardigli, M; Zangheri, M; Prati, S; Mazzeo, R; Roda, A

    2013-01-01

    The characterization of the organic components in a complex, multilayered paint structure is fundamental for studying painting techniques and for authentication and restoration purposes. Proteinaceous materials, such as animal glue, are of particular importance since they are widely used as binders, adhesives and for gilding. Even though proteins are usually detected by chromatographic and proteomic techniques, immunological methods represent an alternative powerful approach to protein analysis thanks to the high specificity of antigen-antibody reactions. Our previous studies demonstrated that ovalbumin and casein could be localized in paint cross-sections with high sensitivity and good spatial resolution (i.e. within the single painting layers) by using chemiluminescent (CL) immunochemical microscope imaging. In the present research work, we describe for the first time the immunolocalization of collagen (the main protein of animal glue) in paint cross-sections by CL imaging microscopy. Two different analytical protocols have been developed, allowing either the detection of collagen or the simultaneous detection of collagen and ovalbumin in the same paint sample. The assays were used to detect collagen and ovalbumin in cross-sections from model samples and historical paintings (a wall painting dated to 1773-1774 and a painted wood panel of the Renaissance period) in order to achieve information on paint techniques and past restoration interventions.

  20. Total tin and organotin speciation in historic layers of antifouling paint on leisure boat hulls.

    PubMed

    Lagerström, Maria; Strand, Jakob; Eklund, Britta; Ytreberg, Erik

    2017-01-01

    Despite their ban on small vessels in 1989 in the EU, organotin compounds (OTCs) are still being released into the environment due to their presence in historic paint layers on leisure boats. 23 paint samples scraped from recreational boats from three countries around the Baltic Sea were analyzed for total tin (Sn) and OTCs. Two antifouling paint products were also subjected to the same analyses. A new method for the detection of Sn in paint flake samples was developed and found to yield more accurate results compared to four different acid digestion methods. A new method was also developed for the extraction of OTCs from ground paint flakes. This endeavor revealed that existing methods for organotin analysis of sediment may not have full recoveries of OTCs if paint flakes are present in the sample. The hull paint samples had Sn concentrations ranging from 25 to 18,000 mg/kg paint and results showed that tributyltin (TBT) was detected in all samples with concentrations as high as 4.7 g (as Sn)/kg paint. TBT was however not always the major OTC. Triphenyltin (TPhT) was abundant in many samples, especially in those originating from Finland. Several other compounds such as monobutyltin (MBT), dibutyltin (DBT), tetrabutyltin (TeBT), monophenyltin (MPhT) and diphenyltin (DPhT) were also detected. These could be the result of degradation occurring on the hull or of impurities in the paint products as they were also identified in the two analyzed paint products. A linear correlation (r(2) = 0.934) was found between the total tin content and the sum of all detected OTCs. The detection of tin can therefore be used to indicate the presence of OTCs on leisure boats.

  1. Remote multispectral imaging with PRISMS and XRF analysis of Tang tomb paintings

    NASA Astrophysics Data System (ADS)

    Lange, Rebecca; Zhang, Qunxi; Liang, Haida

    2011-06-01

    PRISMS (Portable Remote Imaging System for Multispectral Scanning) is a multispectral/hyperspectral imaging system designed for flexible in situ imaging of wall paintings at high resolution (tens of microns) over a large range of distances (less than a meter to over ten meters). This paper demonstrates a trial run of the VIS/NIR (400-880nm) component of the instrument for non-invasive imaging of wall paintings in situ. Wall painting panels from excavated Tang dynasty (618- 907AD) tombs near Xi'an were examined by PRISMS. Pigment identifications were carried out using the spectral reflectance obtained from multispectral imaging coupled with non-invasive elemental analysis using a portable XRF.

  2. 14. INTERIOR DETAIL, FIRST FLOOR OF ADDITION AT SOUTH WALL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. INTERIOR DETAIL, FIRST FLOOR OF ADDITION AT SOUTH WALL OF TOILET ROOM, SHOWING ORNATE PAINTED RADIATOR AND TONGUE AND GROOVE WAINSCOTING. - Mills Hall, Mills College, 5000 MacArthur Boulevard, Oakland, Alameda County, CA

  3. 60. 451 MADISON AVENUE, DRAWING ROOM, NORTH WALL, WEST MURAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    60. 451 MADISON AVENUE, DRAWING ROOM, NORTH WALL, WEST MURAL PAINTING SHOWING A WOMAN (See NY-5635-54 for original location) - Villard Houses, 451-457 Madison Avenue & 24 East Fifty-first Street, New York County, NY

  4. [Spectral analysis of green pigments of painting and colored drawing in northern Chinese ancient architectures].

    PubMed

    Wang, Li-Qin; Yan, Jing; Fan, Xiao-Lei; Ma, Tao

    2010-02-01

    It is important to identify pigments of painting and colored drawing in ancient architectures in order to restore and conserve them. The components of green pigments were detected with X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy-energy dispersive X-ray (SEM-EDX). Twenty-seven samples were collected from painting and colored drawing in northern Chinese ancient architectures in Beijing, Shanxi province and Gansu province. The experiment results showed that emerald green [CuCH3COO]2 x Cu(AsO2)2], a complex of copper aceto-arsenite pigment, had been used as the colored component in fifteen samples, whereas organic materials synthesized in the rest. However, in all samples there were no malachite and atacamite, green pigments commonly used in ancient time a long time ago. These two pigments have been found in Qin Shihuang's Terracotta Army and the wall paintings at Mogao Grettoes, Dunhuang, and some other famous wall paintings and color pottery figurines. However, emerald green was used many years later. It was reported that emerald green was synthesized by Germany in 1814 and had been widely used in China as watercolor on pith paper works and on scroll paintings since the 1850s. Because painting and colored drawing in ancient architectures stands outside, under sunlight and rain, it must be repaired and repainted in less than fifty years. Therefore, it is not surprising that emerald green was used in them. In recent years, artificial organic materials are increasingly used in painting and colored drawing in ancient architectures. From experiments it was also showed that in the same recolored painting and colored drawing, organic materials are usually in the later layers, but emerald green is in the earlier layers. This work supplies a lot of data for the purpose of selecting restoration materials and identifying painting and colored drawing in ancient architectures with a new method.

  5. Microbial evaluation and deterioration of paints and paint-products.

    PubMed

    Obidi, O F; Aboaba, O O; Makanjuola, M S; Nwachukwu, S C U

    2009-09-01

    The microbial quality of materials and final products of a reputable paint industry in Lagos area were analysed. The bacterial contaminants isolated in the paint-products included Bacillus brevis, B. polymyxa, B. laterosporus, Lactobacillus gasseri, L. brevis, Escherichia coli and Proteus mirabilis. The fungal contaminants detected in the paints were mainly Aspergillus niger, A. flavus and Penicillium citrinum. The microbial populations in the raw materials ranged from 1.0 x 10(6) - 9.5 x 10(6) cfu g(-1) for bacteria and between 1.25 x 10(4) and 6.8 x 10(4) cfu g(-1) for fungi while those present in packaging materials ranged from 3.45 x 10(6) - 7.65 x 10(6) cfu g(-1) for bacteria and 2.4 x 10(3) - 2.8 x 10(3) cfu g(-1) for fungi respectively. The bacterial populations in the fresh paint samples monitored every two weeks from the time of production ranged from 1.6 x 10(1) - 4.7 x 10(5) cfu ml(-1) while the fungal populations ranged from 1.0 x 10(1) - 5.5 x 10(3) cfu ml(-1) over a ten-month study period. The optical density at 600 nm increased while transmittance, pH, specific gravity and viscosity of the paint samples decreased over the period suggesting gradual deterioration of the aesthetic qualities of the paint-products with time as indicated by the measured parameters.

  6. A multi-technique approach for the characterization of Roman mural paintings

    NASA Astrophysics Data System (ADS)

    Toschi, Francesco; Paladini, Alessandra; Colosi, Francesca; Cafarelli, Patrizia; Valentini, Veronica; Falconieri, Mauro; Gagliardi, Serena; Santoro, Paola

    2013-11-01

    In the frame of an ongoing archeological study on the Sabina area, a countryside close to Rome, white and red samples of roman wall paintings have been investigated by combining X-ray diffraction and different spectroscopic methodologies, namely laser induced breakdown spectroscopy, μ-Raman and Fourier transform infrared attenuated total reflectance spectroscopy. The used multi-technique approach has allowed the unambiguous identification of the red pigment as red ochre and has provided insight on the provenance of both the pigment and the material used for the realization of the wall paintings. The experimental results have confirmed some assumptions on the use of local materials in roman rural architecture.

  7. Influence of paints formulations on nanoparticles release during their life cycle

    NASA Astrophysics Data System (ADS)

    Fiorentino, Brice; Golanski, Luana; Guiot, Arnaud; Damlencourt, Jean-François; Boutry, Delphine

    2015-03-01

    Pristine nanoparticles (NPs) may present a hazard to humans and the environment, and hence it is important to know to what extent NPs can be freely released from commercialized products in which they are added. The purpose of this study was to identify the parameters of the paint formulation containing SiO2 NPs of 19-nm diameter that could have an impact on the release induced by aging and abrasion. In order to simulate outdoor aging during the life cycle of the product, painted panels were exposed to accelerated weathering experiments in accordance with the norm EN ISO 16474-3:2013. The surface modification of these paints was characterized by scanning electron microscope coupled with energy dispersive spectrometry (SEM-EDS). These analyses showed that the acrylic copolymer binder has undergone a more significant chemical degradation compared with the styrene-acrylic copolymer. To simulate a mechanical aging, abrasion tests were conducted using a Taber Abraser, simulating critical scenarios of the abrasion standard. The particle size distributions and particle concentrations of the abraded particles were measured using an electric low-pressure impactor. After accelerated aging and abrasion tests, we observed a link between the paint degradations occurring with the release of pristine NPs and the embedded pristine NPs. Surface degradation of acrylic copolymer paints was more significant than that of the styrene-acrylic copolymer paints, and this induced a release of NPs 2.7 times higher. Other parameters like TiO2 addition as pigments induced a strong stability of paint against light and water, decreasing the total number of NPs released from paints from 30,000 to 1200 particles/cm3. These results revealed that formulations can be tuned to decrease the number of free NPs released and get a "safe-by-design" product.

  8. Formula for the Removal and Remediation of Polychlorinated Biphenyls in Painted Structures

    NASA Technical Reports Server (NTRS)

    Quinn, Jacqueline; Loftin, Kathleen; Geiger, Cherie

    2010-01-01

    An activated metal treatment system (AMTS) removes and destroys polychlorinated biphenyls (PCBs) found in painted structures or within the binding or caulking material on structures. It may be applied using a "paint-on and wipe-off" process that leaves the structure PCB-free and virtually unaltered in physical form. AMTS is used in conjunction with a solvent solution capable of donating hydrogen atoms. AMTS as a treatment technology has two functions: first, to extract PCBs from the material, and second, to degrade the extracted PCBs. The process for removing PCBs from structures is accomplished as an independent step to the degradation process. The goal is to extract the PCBs out of the paint, without destroying the paint, and to partition the PCBs into an environmentally friendly solvent. The research to date indicates this can be accomplished within the first 24 hours of AMTS contact with the paint. PCBs are extremely hydrophobic and prefer to be in the AMTS over the hardened paint or binder material. The solvent selected must be used to open, but not to destroy, the paint s polymeric lattice structure, allowing pathways for PCB movement out of the paint and into the solvent. A number of solvent systems were tested and are available for use within the AMTS. The second process of the AMTS is the degradation or dehalogenation of the PCBs. The solvent selection for this process is limited to solvents that are capable of donating a hydrogen atom to the PCB structure. Additional AMTS formulation properties that must be addressed for each site-specific application include viscosity and stability. The AMTS must be thick enough to remain where it is applied. Several thickening agents have been tested. Adding a stabilizing agent ensures that the AMTS will not evaporate and leave unprotected, activated metal exposed. During AMTS formulation testing, a number of reagents were evaluated to ensure the rate of dehalogenation was not inhibited by its addition to the system.

  9. Ultraviolet-radiation-curable paints

    SciTech Connect

    Grosset, A M; Su, W F.A.; Vanderglas, E

    1981-09-30

    In product finishing lines, ultraviolet radiation curing of paints on prefabricated structures could be more energy efficient than curing by natural gas fired ovens, and could eliminate solvent emission. Diffuse ultraviolet light can cure paints on three dimensional metal parts. In the uv curing process, the spectral output of radiation sources must complement the absorption spectra of pigments and photoactive agents. Photosensitive compounds, such as thioxanthones, can photoinitiate unsaturated resins, such as acrylated polyurethanes, by a free radical mechanism. Newly developed cationic photoinitiators, such as sulfonium or iodonium salts (the so-called onium salts) of complex metal halide anions, can be used in polymerization of epoxy paints by ultraviolet light radiation. One-coat enamels, topcoats, and primers have been developed which can be photoinitiated to produce hard, adherent films. This process has been tested in a laboratory scale unit by spray coating these materials on three-dimensional objects and passing them through a tunnel containing uv lamps.

  10. Painting in the Year 2000: A Classroom Video Series.

    ERIC Educational Resources Information Center

    Szekely, George

    2000-01-01

    Focuses on a video series showing elementary students discovering new approaches to painting. Describes performances and questions that expand children's views on painting, including painting objects, seeing different ideas for the canvas, and exploring new paint brush forms. (CMK)

  11. Characterization of emissions of volatile organic compounds from interior alkyd paint.

    PubMed

    Fortmann, R; Roache, N; Chang, J C; Guo, Z

    1998-10-01

    Alkyd paint continues to be used indoors for application to wood trim, cabinet surfaces, and some kitchen and bathroom walls. Alkyd paint may represent a significant source of volatile organic compounds (VOCs) indoors because of the frequency of use and amount of surface painted. The U.S. Environmental Protection Agency (EPA) is conducting research to characterize VOC emissions from paint and to develop source emission models that can be used for exposure assessment and risk management. The technical approach for this research involves both analysis of the liquid paint to identify and quantify the VOC contents and dynamic small chamber emissions tests to characterize the VOC emissions after application. The predominant constituents of the primer and two alkyd paints selected for testing were straight-chain alkanes (C9-C12); C8-C9 aromatics were minor constituents. Branched chain alkanes were the predominant VOCs in a third paint. A series of tests were performed to evaluate factors that may affect emissions following application of the coatings. The type of substrate (glass, wallboard, or pine board) did not have a substantial impact on the emissions with respect to peak concentrations, the emissions profile, or the amount of VOC mass emitted from the paint. Peak concentrations of total volatile organic compounds (TVOCs) as high as 10,000 mg/m3 were measured during small chamber emissions tests at 0.5 air exchanges per hour (ACH). Over 90% of the VOCs were emitted from the primer and paints during the first 10 hr following application. Emissions were similar from paint applied to bare pine board, a primed board, or a board previously painted with the same paint. The impact of other variable, including film thickness, air velocity at the surface, and air-exchange rate (AER) were consistent with theoretical predictions for gas-phase, mass transfer-controlled emissions. In addition to the alkanes and aromatics, aldehydes were detected in the emissions during paint

  12. Characterization of Emissions of Volatile Organic Compounds from Interior Alkyd Paint.

    PubMed

    Fortmann, Roy; Roache, Nancy; Chang, John C S; Guo, Zhishi

    1998-10-01

    Alkyd paint continues to be used indoors for application to wood trim, cabinet surfaces, and some kitchen and bathroom walls. Alkyd paint may represent a significant source of volatile organic compounds (VOCs) indoors because of the frequency of use and amount of surface painted. The U.S. Environmental Protection Agency (EPA) is conducting research to characterize VOC emissions from paint and to develop source emission models that can be used for exposure assessment and risk management. The technical approach for this research involves both analysis of the liquid paint to identify and quantify the VOC contents and dynamic small chamber emissions tests to characterize the VOC emissions after application. The predominant constituents of the primer and two alkyd paints selected for testing were straight-chain alkanes (C9-C12); C8-C9 aromatics were minor constituents. Branched chain alkanes were the predominant VOCs in a third paint. A series of tests were performed to evaluate factors that may affect emissions following application of the coatings. The type of substrate (glass, wallboard, or pine board) did not have a substantial impact on the emissions with respect to peak concentrations, the emissions profile, or the amount of VOC mass emitted from the paint. Peak concentrations of total volatile organic compounds (TVOCs) as high as 10,000 mg/m(3) were measured during small chamber emissions tests at 0.5 air exchanges per hour (ACH). Over 90% of the VOCs were emitted from the primer and paints during the first 10 hr following application. Emissions were similar from paint applied to bare pine board, a primed board, or a board previously painted with the same paint. The impact of other variables, including film thickness, air velocity at the surface, and air-exchange rate (AER) were consistent with theoretical predictions for gas-phase, mass transfer-controlled emissions. In addition to the alkanes and aromatics, aldehydes were detected in the emissions during paint

  13. Graffiti for science - erosion painting reveals spatially variable erosivity of sediment-laden flows

    NASA Astrophysics Data System (ADS)

    Beer, Alexander R.; Kirchner, James W.; Turowski, Jens M.

    2016-12-01

    Spatially distributed detection of bedrock erosion is a long-standing challenge. Here we show how the spatial distribution of surface erosion can be visualized and analysed by observing the erosion of paint from natural bedrock surfaces. If the paint is evenly applied, it creates a surface with relatively uniform erodibility, such that spatial variability in the erosion of the paint reflects variations in the erosivity of the flow and its entrained sediment. In a proof-of-concept study, this approach provided direct visual verification that sediment impacts were focused on upstream-facing surfaces in a natural bedrock gorge. Further, erosion painting demonstrated strong cross-stream variations in bedrock erosion, even in the relatively narrow (5 m wide) gorge that we studied. The left side of the gorge experienced high sediment throughput with abundant lateral erosion on the painted wall up to 80 cm above the bed, but the right side of the gorge only showed a narrow erosion band 15-40 cm above the bed, likely due to deposited sediment shielding the lower part of the wall. This erosion pattern therefore reveals spatial stream bed aggradation that occurs during flood events in this channel. The erosion painting method provides a simple technique for mapping sediment impact intensities and qualitatively observing spatially distributed erosion in bedrock stream reaches. It can potentially find wide application in both laboratory and field studies.

  14. EVALUATION OF LOW-VOC LATEX PAINTS

    EPA Science Inventory

    The paper gives results of an evaluation of four commercially available low-VOC (volatile organic compound) latex paints as substitutes for conventional latex paints by assessing both their emission characteristics and their performance as coatings. Bulk analysis indicated that ...

  15. EVALUATION OF LOW-VOC LATEX PAINTS

    EPA Science Inventory

    The paper gives results of an evaluation of four commercially available low-VOC (volatile organic compound) latex paints as substitutes for conventional latex paints by assessing both their emission characteristics and their performance as coatings. Bulk analysis indicated that ...

  16. 49 CFR 173.173 - Paint, paint-related material, adhesives, ink and resins.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Paint, paint-related material, adhesives, ink and... Than Class 1 and Class 7 § 173.173 Paint, paint-related material, adhesives, ink and resins. (a) When... requirements apply. Except as otherwise provided in this part, the description “Paint” is the proper...

  17. 49 CFR 173.173 - Paint, paint-related material, adhesives, ink and resins.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Paint, paint-related material, adhesives, ink and... Than Class 1 and Class 7 § 173.173 Paint, paint-related material, adhesives, ink and resins. (a) When... requirements apply. Except as otherwise provided in this part, the description “Paint” is the proper...

  18. 49 CFR 173.173 - Paint, paint-related material, adhesives, ink and resins.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Paint, paint-related material, adhesives, ink and... Than Class 1 and Class 7 § 173.173 Paint, paint-related material, adhesives, ink and resins. (a) When... requirements apply. Except as otherwise provided in this part, the description “Paint” is the proper...

  19. 49 CFR 173.173 - Paint, paint-related material, adhesives, ink and resins.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Paint, paint-related material, adhesives, ink and... Than Class 1 and Class 7 § 173.173 Paint, paint-related material, adhesives, ink and resins. (a) When... requirements apply. Except as otherwise provided in this part, the description “Paint” is the proper...

  20. 49 CFR 173.173 - Paint, paint-related material, adhesives, ink and resins.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Paint, paint-related material, adhesives, ink and... Than Class 1 and Class 7 § 173.173 Paint, paint-related material, adhesives, ink and resins. (a) When... requirements apply. Except as otherwise provided in this part, the description “Paint” is the proper...

  1. Genotypes of predomestic horses match phenotypes painted in Paleolithic works of cave art.

    PubMed

    Pruvost, Melanie; Bellone, Rebecca; Benecke, Norbert; Sandoval-Castellanos, Edson; Cieslak, Michael; Kuznetsova, Tatyana; Morales-Muñiz, Arturo; O'Connor, Terry; Reissmann, Monika; Hofreiter, Michael; Ludwig, Arne

    2011-11-15

    Archaeologists often argue whether Paleolithic works of art, cave paintings in particular, constitute reflections of the natural environment of humans at the time. They also debate the extent to which these paintings actually contain creative artistic expression, reflect the phenotypic variation of the surrounding environment, or focus on rare phenotypes. The famous paintings "The Dappled Horses of Pech-Merle," depicting spotted horses on the walls of a cave in Pech-Merle, France, date back ~25,000 y, but the coat pattern portrayed in these paintings is remarkably similar to a pattern known as "leopard" in modern horses. We have genotyped nine coat-color loci in 31 predomestic horses from Siberia, Eastern and Western Europe, and the Iberian Peninsula. Eighteen horses had bay coat color, seven were black, and six shared an allele associated with the leopard complex spotting (LP), representing the only spotted phenotype that has been discovered in wild, predomestic horses thus far. LP was detected in four Pleistocene and two Copper Age samples from Western and Eastern Europe, respectively. In contrast, this phenotype was absent from predomestic Siberian horses. Thus, all horse color phenotypes that seem to be distinguishable in cave paintings have now been found to exist in prehistoric horse populations, suggesting that cave paintings of this species represent remarkably realistic depictions of the animals shown. This finding lends support to hypotheses arguing that cave paintings might have contained less of a symbolic or transcendental connotation than often assumed.

  2. Genotypes of predomestic horses match phenotypes painted in Paleolithic works of cave art

    PubMed Central

    Pruvost, Melanie; Bellone, Rebecca; Benecke, Norbert; Sandoval-Castellanos, Edson; Cieslak, Michael; Kuznetsova, Tatyana; Morales-Muñiz, Arturo; O'Connor, Terry; Reissmann, Monika; Hofreiter, Michael; Ludwig, Arne

    2011-01-01

    Archaeologists often argue whether Paleolithic works of art, cave paintings in particular, constitute reflections of the natural environment of humans at the time. They also debate the extent to which these paintings actually contain creative artistic expression, reflect the phenotypic variation of the surrounding environment, or focus on rare phenotypes. The famous paintings “The Dappled Horses of Pech-Merle,” depicting spotted horses on the walls of a cave in Pech-Merle, France, date back ∼25,000 y, but the coat pattern portrayed in these paintings is remarkably similar to a pattern known as “leopard” in modern horses. We have genotyped nine coat-color loci in 31 predomestic horses from Siberia, Eastern and Western Europe, and the Iberian Peninsula. Eighteen horses had bay coat color, seven were black, and six shared an allele associated with the leopard complex spotting (LP), representing the only spotted phenotype that has been discovered in wild, predomestic horses thus far. LP was detected in four Pleistocene and two Copper Age samples from Western and Eastern Europe, respectively. In contrast, this phenotype was absent from predomestic Siberian horses. Thus, all horse color phenotypes that seem to be distinguishable in cave paintings have now been found to exist in prehistoric horse populations, suggesting that cave paintings of this species represent remarkably realistic depictions of the animals shown. This finding lends support to hypotheses arguing that cave paintings might have contained less of a symbolic or transcendental connotation than often assumed. PMID:22065780

  3. 40 CFR 745.65 - Lead-based paint hazards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Lead-based paint hazards. 745.65... CONTROL ACT LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Lead-Based Paint Hazards § 745.65 Lead-based paint hazards. (a) Paint-lead hazard. A paint-lead hazard is any of the...

  4. 40 CFR 745.65 - Lead-based paint hazards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CONTROL ACT LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Lead-Based Paint Hazards § 745.65 Lead-based paint hazards. (a) Paint-lead hazard. A paint-lead hazard is any of the... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Lead-based paint hazards....

  5. Drawing and Painting with Under-Threes.

    ERIC Educational Resources Information Center

    Kolbe, Ursula; Smyth, Jane

    2000-01-01

    Noting that drawing and painting offer very young children powerful ways to explore and communicate thoughts and feelings, this booklet for caregivers and teachers offers suggestions related to painting and drawing for children under 3 years. The booklet discusses what young children can do with drawing and painting materials, including exploring…

  6. Enhanced multifunctional paint for detection of radiation

    DOEpatents

    Farmer, Joseph C.; Moses, Edward Ira; Rubenchik, Alexander M.

    2017-03-07

    An enhanced multifunctional paint apparatus, systems, and methods for detecting radiation on a surface include providing scintillation particles; providing an enhance neutron absorptive material; providing a binder; combining the scintillation particles, the enhance neutron absorptive material, and the binder creating a multifunctional paint; applying the multifunctional paint to the surface; and monitoring the surface for detecting radiation.

  7. Miniature Paintings: Small Size, Big Impact!

    ERIC Educational Resources Information Center

    Hicks, Bill

    2011-01-01

    This article describes a miniature painting project that allows students to research a master painter and then replicate the work on a smaller scale. This lesson focuses on the students' ability to learn to identify style, subject matter, themes, and content in painting through the study of historical paintings, and the application of various…

  8. Mural Painting as Inclusive Art Learning Experience

    ERIC Educational Resources Information Center

    Ho, Kong

    2010-01-01

    Traditional art education, like other academic disciplines, emphasizes competitiveness and individualism. Through a mural painting curriculum, learners participate in mural art and history appreciation, are active in mural theme or content construction, and engage in hands-on mural design and painting processes. When mural paintings are produced…

  9. Stripping Paint From Exterior Wood Surfaces

    Treesearch

    Mark T. Knaebe

    2013-01-01

    Removing paint and other film-forming finishes is a time consuming and often difficult process. In some cases, finishes need to be removed prior to repainting; for example, if the old surface is covered with severely peeled or blistered paint or if excessive paint buildup has caused cross-grain cracking. You must also remove the finish before applying a penetrating...

  10. EMISSIONS OF ODOROUS ALDEHYDES FROM ALKYD PAINT

    EPA Science Inventory

    Aldehyde emissions are widely held responsible for the acrid after-odor of drying alkyd-based paint films. The aldehyde emissions from three different alkyd paints were measured in small environmental chambers. It was found that, for each alkyd paint applied, more than 2 mg of ...

  11. Biodegradation of paint stripper solvents in a modified gas lift loop bioreactor

    SciTech Connect

    Vanderberg-Twary, L.; Steenhoudt, K.; Travis, B.J.; Hanners, J.L.; Foreman, T.M.; Brainard, J.R.

    1997-07-05

    Paint stripping wastes generated during the decontamination and decommissioning of former nuclear facilities contain paint stripping organics (dichloromethane, 2-propanol, and methanol) and bulk materials containing paint pigments. It is desirable to degrade the organic residues as part of an integrated chemical-biological treatment system. The authors have developed a modified gas lift loop bioreactor employing a defined consortium of Thodococcus rhodochrous strain OFS and Hyphomicrobium sp. DM-2 that degrades paint stripper organics. Mass transfer coefficients and kinetic constants for biodegradation in the system were determined. It was found that transfer of organic substrates from surrogate waste into the air and further into the liquid medium in the bioreactor were rapid processes, occurring within minutes. Monod kinetics was employed to model the biodegradation of paint stripping organics. Analysis of the bioreactor process was accomplished with BIOLAB, a mathematical code that simulates coupled mass transfer and biodegradation processes. This code was used to fit experimental data to monod kinetics and to determine kinetic parameters. The BIOLAB code was also employed to compare activities in the bioreactor of individual microbial cultures to the activities of combined cultures in the bioreactor. This code is of benefit for further optimization and scale-up of the bioreactor for treatment of paint stripping and other volatile organic wastes in bulk materials.

  12. Thermal control paints on LDEF: Results of M0003 sub-experiment 18

    NASA Technical Reports Server (NTRS)

    Jaggers, C. H.; Meshishnek, M. J.; Coggi, J. M.

    1993-01-01

    Several thermal control paints were flown on the Long Duration Exposure Facility (LDEF), including the white paints Chemglaze A276, S13GLO, and YB-71, and the black paint D-111. The effects of low earth orbit, which includes those induced by UV radiation and atomic oxygen, varied significantly with each paint and its location on LDEF. For example, samples of Chemglaze A276 located on the trailing edge of LDEF darkened significantly due to UV-induced degradation of the paint's binder, while leading edge samples remained white but exhibited severe atomic oxygen erosion of the binder. Although the response of S13GLO to low earth orbit is much more complicated, it also exhibited greater darkening on trailing edge samples as compared to leading edge samples. In contrast, YB-71 and D-111 remained relatively stable and showed minimal degradation. The performance of these paints as determined by changes in their optical and physical properties, including solar absorptance as well as surface chemical changes and changes in surface morphology is examined. It will also provide a correlation of these optical and physical property changes to the physical phenomena that occurred in these materials during the LDEF mission.

  13. Multispectral Photogrammetric Data Acquisition and Processing Forwall Paintings Studies

    NASA Astrophysics Data System (ADS)

    Pamart, A.; Guillon, O.; Faraci, S.; Gattet, E.; Genevois, M.; Vallet, J. M.; De Luca, L.

    2017-02-01

    In the field of wall paintings studies different imaging techniques are commonly used for the documentation and the decision making in term of conservation and restoration. There is nowadays some challenging issues to merge scientific imaging techniques in a multimodal context (i.e. multi-sensors, multi-dimensions, multi-spectral and multi-temporal approaches). For decades those CH objects has been widely documented with Technical Photography (TP) which gives precious information to understand or retrieve the painting layouts and history. More recently there is an increasing demand of the use of digital photogrammetry in order to provide, as one of the possible output, an orthophotomosaic which brings a possibility for metrical quantification of conservators/restorators observations and actions planning. This paper presents some ongoing experimentations of the LabCom MAP-CICRP relying on the assumption that those techniques can be merged through a common pipeline to share their own benefits and create a more complete documentation.

  14. Characterizing microbial diversity and damage in mural paintings.

    PubMed

    Rosado, Tânia; Mirão, José; Candeias, António; Caldeira, Ana Teresa

    2015-02-01

    Mural paintings are some of the oldest and most important cultural expressions of mankind and play an important role for the understanding of societies and civilizations. These cultural assets have high economic and cultural value and therefore their degradation has social and economic impact. The present work presents a novel microanalytical approach to understand the damages caused by microbial communities in mural paintings. This comprises the characterization and identification of microbial diversity and evaluation of damage promoted by their biological activity. Culture-dependent methods and DNA-based approaches like denaturing gradient gel electrophoresis (DGGE) and pyrosequencing are important tools in the isolation and identification of the microbial communities allowing characterization of the biota involved in the biodeterioration phenomena. Raman microspectrometry, infrared spectrometry, and variable pressure scanning electron microscopy coupled with energy-dispersive X-ray spectrometry are also useful tools for evaluation of the presence of microbial contamination and detection of the alteration products resulting from metabolic activity of the microorganisms. This study shows that the degradation status of mural paintings can be correlated to the presence of metabolically active microorganisms.

  15. Basking Behavior of Painted Turtles.

    ERIC Educational Resources Information Center

    Zipko, Stephen J.

    1982-01-01

    Examines the basking postures of captive eastern painted turtles exposed to two different sources of illumination (white floor lamps and infrared heat lamps) and three types of substrates (sphagnum, rock, wood) and discusses possible ecological and evolutionary significance of these behaviors. (Author/JN)

  16. Paint the World with Light

    ERIC Educational Resources Information Center

    Gran, David

    2010-01-01

    Two classrooms on opposite sides of the world happened to be working on a very similar project at the same time. In both Shanghai, China, and Palm Springs, California, students were learning how to turn their flashlights and other light-emitting objects into paintbrushes. Light painting is a form of long-exposure photography in which the shutter…

  17. Basking Behavior of Painted Turtles.

    ERIC Educational Resources Information Center

    Zipko, Stephen J.

    1982-01-01

    Examines the basking postures of captive eastern painted turtles exposed to two different sources of illumination (white floor lamps and infrared heat lamps) and three types of substrates (sphagnum, rock, wood) and discusses possible ecological and evolutionary significance of these behaviors. (Author/JN)

  18. Controlling Color in Oil Painting.

    ERIC Educational Resources Information Center

    Amorino, Joseph

    1990-01-01

    Explains how a veil control method allows secondary students to use oil paints in the classroom without difficulties of control, manageability, and clean up. Outlines how to prepare and apply oil glazes. Maintains that this method enhances students' studio skills and helps them appreciate the works of the great masters. (KM)

  19. Stop and Paint the Flowers.

    ERIC Educational Resources Information Center

    Phillips, Shelley

    2002-01-01

    Describes an art lesson where students used watercolors to paint a flower bouquet arranged in a vase. Explains that the students viewed examples of flower bouquets by artists such as Vincent van Gogh and Odilon Redon. Discusses, in detail, the process of creating the artworks. (CMK)

  20. Paint the World with Light

    ERIC Educational Resources Information Center

    Gran, David

    2010-01-01

    Two classrooms on opposite sides of the world happened to be working on a very similar project at the same time. In both Shanghai, China, and Palm Springs, California, students were learning how to turn their flashlights and other light-emitting objects into paintbrushes. Light painting is a form of long-exposure photography in which the shutter…

  1. Stop and Paint the Flowers.

    ERIC Educational Resources Information Center

    Phillips, Shelley

    2002-01-01

    Describes an art lesson where students used watercolors to paint a flower bouquet arranged in a vase. Explains that the students viewed examples of flower bouquets by artists such as Vincent van Gogh and Odilon Redon. Discusses, in detail, the process of creating the artworks. (CMK)

  2. Passive Wireless Hermetic Environment Monitoring System for Spray Painting Workshop

    PubMed Central

    Wang, Lifeng; Ma, Jingjing; Huang, Yan; Tang, Dan; Huang, Qing-An

    2016-01-01

    Passive wireless sensors have the advantages of operating without a power supply and remote sensing capability. Hence, they are very suitable for some harsh environments, such as hermetic environments, rotating parts, or very high temperature environments. The spray painting workshop is such a harsh environment, containing a large amount of flammable paint mist and organic gas. Aiming at this special environment of spray painting workshop, a passive wireless hermetic environment monitoring system was designed, fabricated, and demonstrated. The proposed system is composed of a transponder and a reader, and the circuit design of each part is given in detail in this paper. The power and the data transmission between the transponder and the reader are realized by the inductive coupling mechanism. Utilizing the back scatter modulation and channel multiplexing, the frequency signals generated by three different environmental sensors—together with their interfaces in the transponder—are wirelessly read out by the reader. Because of the harsh environment of the spray painting room, the package of the monitoring system is quite important. Three different kinds of filter films for the system package were compared. The experimental results show that the composite filter film aluminum anodic oxide/polytetrafluoroethylene (AAO/PTFE) has the best performance. After fabrication, the measured temperature, humidity, and pressure sensitivities were measured and found to be 180 Hz/°C in the range of 0~60 °C, 100 Hz/%RH in the range of 15~95 %RH, and 42 Hz/hPa in the range of 600~1100 hPa, respectively. Additionally, the remote sensing distance of the monitoring system reaches 4 cm. Finally, the passive wireless hermetic environment monitoring system was installed on the glass wall of the spray painting workshop and was successfully demonstrated. PMID:27490546

  3. Passive Wireless Hermetic Environment Monitoring System for Spray Painting Workshop.

    PubMed

    Wang, Lifeng; Ma, Jingjing; Huang, Yan; Tang, Dan; Huang, Qing-An

    2016-08-01

    Passive wireless sensors have the advantages of operating without a power supply and remote sensing capability. Hence, they are very suitable for some harsh environments, such as hermetic environments, rotating parts, or very high temperature environments. The spray painting workshop is such a harsh environment, containing a large amount of flammable paint mist and organic gas. Aiming at this special environment of spray painting workshop, a passive wireless hermetic environment monitoring system was designed, fabricated, and demonstrated. The proposed system is composed of a transponder and a reader, and the circuit design of each part is given in detail in this paper. The power and the data transmission between the transponder and the reader are realized by the inductive coupling mechanism. Utilizing the back scatter modulation and channel multiplexing, the frequency signals generated by three different environmental sensors-together with their interfaces in the transponder-are wirelessly read out by the reader. Because of the harsh environment of the spray painting room, the package of the monitoring system is quite important. Three different kinds of filter films for the system package were compared. The experimental results show that the composite filter film aluminum anodic oxide/polytetrafluoroethylene (AAO/PTFE) has the best performance. After fabrication, the measured temperature, humidity, and pressure sensitivities were measured and found to be 180 Hz/°C in the range of 0~60 °C, 100 Hz/%RH in the range of 15~95 %RH, and 42 Hz/hPa in the range of 600~1100 hPa, respectively. Additionally, the remote sensing distance of the monitoring system reaches 4 cm. Finally, the passive wireless hermetic environment monitoring system was installed on the glass wall of the spray painting workshop and was successfully demonstrated.

  4. Analytical strategies for characterizing organic paint media using gas chromatography/mass spectrometry.

    PubMed

    Colombini, Maria Perla; Andreotti, Alessia; Bonaduce, Ilaria; Modugno, Francesca; Ribechini, Erika

    2010-06-15

    Throughout history, artists have experimented with a variety of organic-based natural materials, using them as paint binders, varnishes, and ingredients for mordants in gildings. Artists often use many layers of paint to produce particular effects. How we see a painting is thus the final result of how this complex, highly heterogeneous, multimaterial, and multilayered structure interacts with light. The chemical characterization of the organic substances in paint materials is of great importance for artwork conservation because the organic components of the paint layers are particularly subject to degradation. In addition, understanding the organic content and makeup of paint materials allows us to differentiate between the painting techniques that have been used over history. Applying gas chromatography/mass spectrometry (GC/MS) analysis to microsamples of paint layers is widely recognized as the best approach for identifying organic materials, such as proteins, drying oils, waxes, terpenic resins, and polysaccharide gums. The method provides essential information for reconstructing artistic techniques, assessing the best conditions for long-term preservation, and planning restoration. In this Account, we summarize the more common approaches adopted in the study of the organic components of paint materials. Our progress in developing GC/MS analytical procedures in the field of cultural heritage is presented, focusing on problems that arise from (i) the presence of mixtures of many chemically complex and degraded materials, (ii) the interference of inorganic species, (iii) the small size of the samples, and (iv) the risk of contamination. We outline some critical aspects of the analytical strategy, such as the need to optimize specific wet-chemical sample pretreatments in order to separate the various components, hydrolyze macromolecular analytes, clean-up inorganic ions, and derivatize polar molecules for subsequent GC/MS separation and identification. We also

  5. Real-Time Imaging of Plant Cell Wall Structure at Nanometer Scale, with Respect to Cellulase Accessibility and Degradation Kinetics (Presentation)

    SciTech Connect

    Ding, S. Y.

    2012-05-01

    Presentation on real-time imaging of plant cell wall structure at nanometer scale. Objectives are to develop tools to measure biomass at the nanometer scale; elucidate the molecular bases of biomass deconstruction; and identify factors that affect the conversion efficiency of biomass-to-biofuels.

  6. But when was it painted?

    NASA Astrophysics Data System (ADS)

    Lundstad, E.; Woll, G.

    2009-04-01

    The Munch Museum, Oslo, Norway, is dedicated to the visual works of the famous Norwegian painter Edvard Munch (1863 - 1944). Edvard Munch was a symbolist, expressionist painter and printmaker from Oslo, Norway. He was regarded as the pioneer of the amazing Expressionist movement. His art work from the late 1800's is the most well known, but his later work is gradually attracting more attention and is quite an inspiration of many of today's artists. The Munch Museum catalogue for 2008 contains about 1700 paintings of which virtually very few have a precise date. Even when the artist has written the year on the painting itself, there may be a significant uncertainty about this date, and partly due to unclear writing making it difficult to interpret the numbers. This means that other sources need to be applied to verify an accurate date. The climatologist at the Norwegian Meteorological Institute can help dating paintings of Munch. E. g. the painting "Standing Woman with Arms Folded". The painting shows a woman in front of a hill with much snow. The location is almost certainty Grimsrød on Jeløya, a property Munch began renting on March 1, 1913. Jeløya is an island at the southeastcoast of Norway near the town Moss. Jeløya has usually not so much snow because it is near by the sea and windy. The last digit in the date is unclear and has been read as both '3' and '5'. The woman in the portrait, Ingeborg Kaurin, was Munch's model up to the beginning of 1915, so both dates are possible. The year written on the painting has been read as both 1913 and 1915, and since 1974 it has usually been interpreted as 1913 (Stenersensamlingen's catalogue 1974). In the project "But when was it painted?" disclose that it could be another year. One way to reconsider when a painting was painted is to study geophysical characteristics and consider historical observations of snow. The method that is used here is to study daily meteorological snow data from this period from the

  7. The photodegradation of cadmium yellow paints in Henri Matisse's Le Bonheur de vivre (1905-1906)

    NASA Astrophysics Data System (ADS)

    Mass, Jennifer L.; Opila, Robert; Buckley, Barbara; Cotte, Marine; Church, Jonathan; Mehta, Apurva

    2013-04-01

    Evidence for the alteration of the yellow paints in Henri Matisse's Le Bonheur de vivre (1905-1906, The Barnes Foundation) has been observed since the 1990s. The changes in this iconic work of Matisse's Fauvist period include lightening, darkening, and flaking of the yellow paints. Handheld X-ray fluorescence (XRF) and multispectral imaging surveys reveal that the degradation is confined to cadmium yellow (CdS) paints. The discoloration of cadmium yellow paints in Impressionist, Post-Impressionist and early modernist work from the 1880s through the 1920s has been ascribed to the photo-oxidative degradation of CdS. Preliminary investigations of the degraded yellow paints in this work involved Cd LIII-edge X-ray Absorption Near Edge Spectroscopy (XANES) at the Stanford Synchrotron Radiation Light Source (SSRL Menlo Park, California) and Scanning Electron Microscopy-energy dispersive X-ray analysis (SEM-EDS) at the Winterthur Museum Scientific Research and Analysis Laboratory. To determine if the visual changes in the paints did in fact indicate photo-oxidative degradation and if different chemistries could be observed for the lightened versus darkened regions, synchrotron radiation-micro Fourier Transform InfraRed (SR-μFTIR) spectroscopy, X-ray Fluorescence (SR-μXRF) mapping and micro X-ray Absorption Near Edge Spectroscopy (μXANES) mapping at the Cd LIII-edge of the altered paint cross-sections were carried out at the European synchrotron radiation facility (ESRF, Grenoble, France) beamline ID-21. The goal is to elucidate the discoloration mechanisms observed in the paint using elemental and speciation mapping. The μXANES mapping and SR-FTIR imaging showed a substantial enrichment of CdCO3 in the off-white surface crust of the faded/discolored CdS paint. This suggests that the CdCO3 is present as an insoluble photodegradation product rather than solely a paint filler or starting reagent. Additionally, oxalates and sulfates were found to be concentrated at the

  8. Salt damage of stone, plaster and painted layers at a medieval church, South-Hungary

    NASA Astrophysics Data System (ADS)

    Török, Ákos; Galambos, Éva

    2016-04-01

    The Chapel of Pécsvárad is one of the best preserved and oldest medieval stone monument in South Hungary. It dates back to the 11th century. The interior of the chapel is decorated with wall paintings, which are later and probably originating from the late 12th century. The wall painting is partly preserved and it is located on an interior stone wall of the chapel facing to the East. The wall painting shows various forms of damage from salt efflorescence to chipping. The current research provides information on the in situ and laboratory analyses of salts, plasters, pigments and stone material suggesting mechanisms of decay that lead to partial loss of the painting. Both on site techniques and laboratory analyses were performed. Imaging techniques such as UV luminescence and IR thermography were used to identify the moist and salt covered zones on the wall surface. Portable moisture meter were also applied to map the wet zones in the interior and also at the external part of the chapel. Schmidt hammer and Duroscop were used for testing the surface strength of stone. Laboratory tests were focused on mineralogical and chemical compositional analyses. Small samples of stone, mortar, plaster and pigments were tested by optical microscopy, SEM-EDX, XRD and Thermogravimetric analyses. According to our tests the chapel was predominantly made of porous limestone and sandstone. Laboratory analyses proved that the major salt responsible for the damage of external walls are gypsum and halite, while in the interior part higher amount of halite and significant amount of sodium-nitrate were found besides gypsum. The painted layers are on Byzantine-type of plaster with organic compounds (plant fragments) and with a substrate layer rich in calcium carbonate. The identified pigments are dominantly earth pigments such as iron-oxide containing red and yellow (ochre) and green earth. A unique preservation of ultramarine blue in Hungary was found on the wall painting. The partial

  9. U.S. BICENTENNIAL EXPOSITION & FINISHED PAINTED AMERICAN FLAG ON VAB

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Finishing touches on the largest American flag ever painted were completed today on the south side of the Vehicle Assembly Building at KSC's Launch Complex 39. The flag was painted as part of 3rd Century America, the U. S. Bicentennial Exposition on Science and Technology to be held here from May 30 through September 7. The flag is located on the western side of the VAB's south wall. Still to be painted is the American Revolution Bicentennial Administration's [ARBA] distinctive emblem. This will be placed on the eastern side of the south wall and should be completed by mid-May. The flag is 209 feet long and 100 feet in width. Each of its 13 red and white bars is nearly 8 and a half feet wide. The ARBA symbol will be 110 feet in diameter.

  10. [Illness caused by water-based paints?].

    PubMed

    Birkeland, G; Zahlsen, K; Aas, K

    1994-08-20

    Illness caused by the indoor environment is a challenging and complicated field to investigate. Emissions from paints may contribute to the problems. Several components of water-based paints evaporate for a long time after painting, and some of them may affect human biology. We describe one patient who has experienced symptoms caused by water-based paint. Different reaction mechanisms may be involved, and these are discussed. Components which may elicit biological effects are listed and discussed. Physicians should be aware of the possibility that a few patients may suffer from illness caused by emissions from modern paints.

  11. Toxic reaction to inhaled paint fumes.

    PubMed Central

    Atkinson, L.; Ince, P.; Smith, N. M.; Taylor, R.

    1989-01-01

    An acute confusional state was observed to follow heavy exposure to polyurethane gloss paint fumes in a previously healthy 60 year old man. This state remitted over a 3-day period, but was followed by transient bone marrow suppression and evidence of liver cell damage. The corroborated absence of other toxins and the temporal association of exposure to paint fumes suggest that a volatile paint component was responsible. White spirit is the major volatile solvent in polyurethane gloss paint. Ingestion of related aliphatic hydrocarbons has been reported to cause nausea, drowsiness and hepatotoxicity, but these symptoms have not previously been documented following excessive inadvertent inhalation of paint fumes. Images Figure 1 PMID:2602252

  12. Bleaching of red lake paints in encaustic mummy portraits

    NASA Astrophysics Data System (ADS)

    Miliani, Costanza; Daveri, Alessia; Spaabaek, Lin; Romani, Aldo; Manuali, Valentina; Sgamellotti, Antonio; Brunetti, Brunetto Giovanni

    2010-09-01

    The present paper reports on the study of the development of whitish opacity in pink paints in encaustic mummy portraits. Non-invasive measurements carried out on two encaustic portraits belonging to the Ny Carlsberg Glyptotek, Copenhagen, by reflectance FTIR and UV-vis fluorescence have shown that the areas prone to the bleaching phenomenon had been painted with melted beeswax and an anthraquinone vegetal lake mixed with calcium sulphate hemihydrate and dihydrate. The hypothesis that the bleaching disease was neither related to a degradation of the dyes nor to an alteration of the wax but rather to a dehydration-hydration reaction of the CaSO4-H2O system, has been corroborated by the analyses of two microsamples from the bleached areas and ascertained by accelerated ageing experiments on encaustic models.

  13. Order-fractal transitions in abstract paintings

    SciTech Connect

    Calleja, E.M. de la; Cervantes, F.; Calleja, J. de la

    2016-08-15

    In this study, we determined the degree of order for 22 Jackson Pollock paintings using the Hausdorff–Besicovitch fractal dimension. Based on the maximum value of each multi-fractal spectrum, the artworks were classified according to the year in which they were painted. It has been reported that Pollock’s paintings are fractal and that this feature was more evident in his later works. However, our results show that the fractal dimension of these paintings ranges among values close to two. We characterize this behavior as a fractal-order transition. Based on the study of disorder-order transition in physical systems, we interpreted the fractal-order transition via the dark paint strokes in Pollock’s paintings as structured lines that follow a power law measured by the fractal dimension. We determined self-similarity in specific paintings, thereby demonstrating an important dependence on the scale of observations. We also characterized the fractal spectrum for the painting entitled Teri’s Find. We obtained similar spectra for Teri’s Find and Number 5, thereby suggesting that the fractal dimension cannot be rejected completely as a quantitative parameter for authenticating these artworks. -- Highlights: •We determined the degree of order in Jackson Pollock paintings using the Hausdorff–Besicovitch dimension. •We detected a fractal-order transition from Pollock’s paintings between 1947 and 1951. •We suggest that Jackson Pollock could have painted Teri’s Find.

  14. Evaluation of low-VOC latex paints

    SciTech Connect

    Chang, J.C.S.; Fortmann, R.C.; Roache, N.F.; Lao, H.C.

    1999-01-01

    The paper gives results of an evaluation of four commercially available low-VOC (volatile organic compound) latex paints as substitutes for conventional latex paints by assessing both their emission characteristics and their performance as coatings. Bulk analysis indicated that the VOC contents of all four paints are considerably lower than those of conventional latex paints. Low-VOC emissions were confirmed by small chamber emission tests. However, sigificant emissions of several aldehydes, especially formaldehyde, were detected from two of the paints. ASTM methods were used to evaluate the hiding power, scrubbability, washability, dry to touch, and yellowing index. The results indicated that one of the low-VOC paints tested showed performance equivalent or superior to that of a widely used conventional latex paint used as a control. It was concluded that low-VOC latex paint can be a viable option to replace conventional latex paints for prevention of indoor air pollution. However, paints marketed as low-VOC may still have significant emissions of some individual VOCs, and some may not have performance characteristics matching those of conventional latex paints.

  15. Evaluation of low-VOC latex paints

    SciTech Connect

    Chang, J.C.S.; Fortmann, R.C.; Roache, N.F.; Lao, H.C.

    1999-11-01

    The paper gives results of an evaluation of four commercially available low-VOC (volatile organic compound) latex paints as substitutes for conventional latex paints by assessing both their emission characteristics and their performance as coatings. Bulk analysis indicated that the VOC contents of all four paints are considerably lower than those of conventional latex paints. Low-VOC emissions were confirmed by small chamber emission tests. However, sigificant emissions of several aldehydes, especially formaldehyde, were detected from two of the paints. ASTM methods were used to evaluate the hiding power, scrubbability, washability, dry to touch, and yellowing index. The results indicated that one of the low-VOC paints tested showed performance equivalent or superior to that of a widely used conventional latex paint used as a control. It was concluded that low-VOC latex paint can be a viable option to replace conventional latex paints for prevention of indoor air pollution. However, paints marketed as low-VOC may still have significant emissions of some individual VOCs, and some may not have performance characteristics matching those of conventional latex paints.

  16. The influence of photocatalytic interior paints on indoor air quality

    NASA Astrophysics Data System (ADS)

    Auvinen, Joonas; Wirtanen, Leif

    2008-06-01

    A clean indoor air is important for the well-being and health of people. Lately, new photocatalytic paints have been launched on the market, which are claimed to have air-purifying effects. Photocatalysis initiates radical reactions. Radicals are formed when a photocatalyst (e.g. TiO2) is subjected to radiation. Typical radicals are the hydroxyl radical (radOH) and the superoxide radical (radO2-). Radicals cause chain reactions, which degrade and decompose organic compounds. The end products of these chain reactions are water and carbon dioxide, if the reactions are fully completed (mineralization). If mineralization does not take place, then a great number of side products can be formed, whose properties are not well understood. The side products of photocatalytic reactions can be permanent and stabile. The decomposition of indoor air impurities on the surface of photocatalytic paints is not obvious. The ability of photocatalytic indoor paints to reduce chemical indoor air impurities is the key issue of this study. Six different paints with different binder systems, such as lime, polyorganic siloxane, silica sol-gel and organic binders, were examined. The experiments were divided into three topics: degradation of an organic binder, photocatalytic decomposition of formaldehyde, and a volatile organic compound (VOC) mixture consisting of five different indoor air VOCs. All tests were carried out in an environmental test chamber under dynamic conditions. The test results indicate that many indoor pollutants are generated under normal- and UVA-light. Typical compounds formed include formaldehyde, acetone, acetaldehyde, etc. A clear decrease of formaldehyde or the VOC mixture concentration was not observed. All possibly generated compounds could not be collected or analyzed in this research project, but the measurements show that photocatalytic reactions do not generate only carbon dioxide and water. Photocatalytic decomposition of indoor air impurities can, however

  17. THz imaging studies of painted samples to guide cultural heritage investigations at the Enkleistra of St. Neophytos in Paphos, Cyprus

    NASA Astrophysics Data System (ADS)

    Radpour, Roxanne; Bajwa, Neha; Garritano, James; Sung, Shijun; Balonis-Sant, Magdalena; Tewari, Priyamvada; Grundfest, Warren; Kakoulli, Ioanna; Taylor, Zachary

    2014-09-01

    Terahertz (THz) imaging is a relatively new non-destructive analytical technique that is transitioning from established application research areas such as defense and biomedicine to studies of cultural heritage artifacts. Our research adopts a THz medical imaging system, originally designed for in vivo tissue hydration sensing, to acquire high contrast imagery of painted plaster samples in order to assess the ability of the system to image the Byzantine wall paintings at the Enkleistra of St. Neophytos in Paphos, Cyprus. The original 12th century paintings show evidence of later painting phases overlapping earlier iconography. A thin layer of lead white (2PbCO3·Pb(OH)2) underlies, in parts, later wall paintings, concealing the original painting scheme beneath. Traditional imaging modalities have been unable to image the underlying iconography due to a combination of absorption and scattering. We aim to use THz imaging and novel optical design to probe beyond the visible surface and perform in situ analysis of iconography beneath the lead white layer. Imaging results of painted plaster mock-ups covered with a thin layer of lead white and/or chalk, as well as of a painted wooden panel with obscured writing, are presented, and from these images sufficient contrast for feature identification is demonstrated. Preliminary results from the analysis of these mock-ups confirmed the utility of this technique and its potential to image concealed original paintings in the Enkleistra of St. Neophytos. The results encourage analysis of THz scattering within paint and plaster materials to further improve spatial resolution and penetration depth in THz imaging systems.

  18. Physiological Degradation of Pectin in Papaya Cell Walls: Release of Long Chains Galacturonans Derived from Insoluble Fractions during Postharvest Fruit Ripening.

    PubMed

    do Prado, Samira B R; Melfi, Paulo R; Castro-Alves, Victor C; Broetto, Sabrina G; Araújo, Elias S; do Nascimento, João R O; Fabi, João P

    2016-01-01

    Papaya (Carica papaya L.) is a fleshy fruit that presents a rapid pulp softening during ripening. However, the timeline on how papaya pectinases act in polysaccharide solubilization and the consequent modification of the cell wall fractions during ripening is still not clear. In this work, the gene expression correlations between, on one hand, 16 enzymes potentially acting during papaya cell wall disassembling and, on the other hand, the monosaccharide composition of cell wall fractions during papaya ripening were evaluated. In order to explain differences in the ripening of papaya samplings, the molecular mass distribution of polysaccharides from water-soluble and oxalate-soluble fractions (WSF and OSF, respectively), as well as the oligosaccharide profiling from the WSF fraction, were evaluated by high performance size exclusion chromatography coupled to a refractive index detector and high performance anion-exchange chromatography coupled to pulse amperometric detection analyses, respectively. Results showed that up-regulated polygalacturonase and β-galactosidase genes were positively correlated with some monosaccharide profiles. In addition, an overall increase in the retention time of high molecular weight (HMW) and low molecular weight (LMW) polysaccharides in WSF and OSF was shown. The apparent disappearance of one HMW peak of the OSF may result from the conversion of pectin that were crosslinked with calcium into more soluble forms through the action of PGs, which would increase the solubilization of polysaccharides by lowering their molecular weight. Thus, the results allowed us to propose a detailed process of papaya cell wall disassembling that would affect sensorial properties and post-harvesting losses of this commercially important fruit.

  19. Physiological Degradation of Pectin in Papaya Cell Walls: Release of Long Chains Galacturonans Derived from Insoluble Fractions during Postharvest Fruit Ripening

    PubMed Central

    do Prado, Samira B. R.; Melfi, Paulo R.; Castro-Alves, Victor C.; Broetto, Sabrina G.; Araújo, Elias S.; do Nascimento, João R. O.; Fabi, João P.

    2016-01-01

    Papaya (Carica papaya L.) is a fleshy fruit that presents a rapid pulp softening during ripening. However, the timeline on how papaya pectinases act in polysaccharide solubilization and the consequent modification of the cell wall fractions during ripening is still not clear. In this work, the gene expression correlations between, on one hand, 16 enzymes potentially acting during papaya cell wall disassembling and, on the other hand, the monosaccharide composition of cell wall fractions during papaya ripening were evaluated. In order to explain differences in the ripening of papaya samplings, the molecular mass distribution of polysaccharides from water-soluble and oxalate-soluble fractions (WSF and OSF, respectively), as well as the oligosaccharide profiling from the WSF fraction, were evaluated by high performance size exclusion chromatography coupled to a refractive index detector and high performance anion-exchange chromatography coupled to pulse amperometric detection analyses, respectively. Results showed that up-regulated polygalacturonase and β-galactosidase genes were positively correlated with some monosaccharide profiles. In addition, an overall increase in the retention time of high molecular weight (HMW) and low molecular weight (LMW) polysaccharides in WSF and OSF was shown. The apparent disappearance of one HMW peak of the OSF may result from the conversion of pectin that were crosslinked with calcium into more soluble forms through the action of PGs, which would increase the solubilization of polysaccharides by lowering their molecular weight. Thus, the results allowed us to propose a detailed process of papaya cell wall disassembling that would affect sensorial properties and post-harvesting losses of this commercially important fruit. PMID:27512402

  20. Texton-based analysis of paintings

    NASA Astrophysics Data System (ADS)

    van der Maaten, Laurens J. P.; Postma, Eric O.

    2010-08-01

    The visual examination of paintings is traditionally performed by skilled art historians using their eyes. Recent advances in intelligent systems may support art historians in determining the authenticity or date of creation of paintings. In this paper, we propose a technique for the examination of brushstroke structure that views the wildly overlapping brushstrokes as texture. The analysis of the painting texture is performed with the help of a texton codebook, i.e., a codebook of small prototypical textural patches. The texton codebook can be learned from a collection of paintings. Our textural analysis technique represents paintings in terms of histograms that measure the frequency by which the textons in the codebook occur in the painting (so-called texton histograms). We present experiments that show the validity and effectiveness of our technique for textural analysis on a collection of digitized high-resolution reproductions of paintings by Van Gogh and his contemporaries. As texton histograms cannot be easily be interpreted by art experts, the paper proposes to approaches to visualize the results on the textural analysis. The first approach visualizes the similarities between the histogram representations of paintings by employing a recently proposed dimensionality reduction technique, called t-SNE. We show that t-SNE reveals a clear separation of paintings created by Van Gogh and those created by other painters. In addition, the period of creation is faithfully reflected in the t-SNE visualizations. The second approach visualizes the similarities and differences between paintings by highlighting regions in a painting in which the textural structure of the painting is unusual. We illustrate the validity of this approach by means of an experiment in which we highlight regions in a painting by Monet that are not very "Van Gogh-like". Taken together, we believe the tools developed in this study are well capable of assisting for art historians in support of

  1. Attenuated total reflection micro FTIR characterisation of pigment-binder interaction in reconstructed paint films.

    PubMed

    Mazzeo, R; Prati, S; Quaranta, M; Joseph, E; Kendix, E; Galeotti, M

    2008-09-01

    The interaction of pigments and binding media may result in the production of metal soaps on the surface of paintings which modifies their visible appearance and state of conservation. To characterise more fully the metal soaps found on paintings, several historically accurate oil and egg yolk tempera paint reconstructions made with different pigments and naturally aged for 10 years were submitted to attenuated total reflectance Fourier transform infrared (ATR FTIR) microspectroscopic analyses. Standard metal palmitates were synthesised and their ATR spectra recorded in order to help the identification of metal soaps. Among the different lead-based pigments, red lead and litharge seemed to produce a larger amount of carboxylates compared with lead white, Naples yellow and lead tin yellow paints. Oil and egg tempera litharge and red lead paints appeared to be degraded into lead carbonate, a phenomenon which has been observed for the first time. The formation of metal soaps was confirmed on both oil and egg tempera paints based on zinc, manganese and copper and in particular on azurite paints. ATR mapping analyses showed how the areas where copper carboxylates were present coincided with those in which azurite was converted into malachite. Furthermore, the key role played by manganese in the production of metals soaps on burnt and raw sienna and burnt and raw umber paints has been observed for the first time. The formation of copper, lead, manganese, cadmium and zinc metal soaps was also identified on egg tempera paint reconstructions even though, in this case, the overlapping of the spectral region of the amide II band with that of metal carboxylates made their identification difficult.

  2. Results of examination of the A276 white and Z306 black thermal control paint disks flown on LDEF

    NASA Technical Reports Server (NTRS)

    Golden, Johnny L.

    1992-01-01

    Specimens of A276 white and Z306 black thermal control paints were analyzed for the effects of space environmental exposure as part of the Long Duration Exposure Facility (LDEF) Materials Special Investigation Group activity. The specimens, actually disks or spots of paint on tray clamps, were located at regular intervals on all LDEF longerons and intercostals. The principle conclusions from the analysis are: UV exposure degraded the surface resin of A276 paint, with coating solar absorptance increasing with UV exposure; contamination, though detected, was not enough to have adversely affected optical properties; atomic oxygen eroded resin on specimens with incidence angles of up to 100 deg; the erosion of Z306 paint on leading edge specimens removed a minimum of 10 microns of that coating; and the erosion of A276 paint at up to 80 deg incidence angle resulted in near original condition solar absorptance readings.

  3. AZW-LA-II White Paint on Swift: Lessons Learned from First Time Flying on Spacecraft Radiators

    NASA Technical Reports Server (NTRS)

    Choi, Michael K.

    2004-01-01

    AZ-Tek's AZW-LA-II low solar absorptance white paint was previously flown as a flight experiment, and is being flown as a calorimeter. However it has never been flown as a thermal coating of radiators on an operational spacecraft before. This paint has the lowest solar absorptance among all white paints, and a very small degradation. Its cost is many times more expensive than white paints that have a higher solar absorptance. To meet the thermal requirements of the Swift Burst Alert Telescope (BAT) Detector Array and X-Ray Telescope (XRT) focal plane camera assembly (FPCA) charged coupled device (CCD), AZW-LA-II is used as the thermal coating for the BAT and XRT radiators. This paper presents the lessons learned from flying this low solar absorptance white paint as a thermal coating of radiators on an operational spacecraft for the first time.

  4. Results of examination of the A276 white and Z306 black thermal control paint disks flown on LDEF

    NASA Technical Reports Server (NTRS)

    Golden, Johnny L.

    1992-01-01

    Specimens of A276 white and Z306 black thermal control paints were analyzed for the effects of space environmental exposure as part of the Long Duration Exposure Facility (LDEF) Materials Special Investigation Group activity. The specimens, actually disks or spots of paint on tray clamps, were located at regular intervals on all LDEF longerons and intercostals. The principle conclusions from the analysis are: UV exposure degraded the surface resin of A276 paint, with coating solar absorptance increasing with UV exposure; contamination, though detected, was not enough to have adversely affected optical properties; atomic oxygen eroded resin on specimens with incidence angles of up to 100 deg; the erosion of Z306 paint on leading edge specimens removed a minimum of 10 microns of that coating; and the erosion of A276 paint at up to 80 deg incidence angle resulted in near original condition solar absorptance readings.

  5. Liquid Wall Chambers

    SciTech Connect

    Meier, W R

    2011-02-24

    The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

  6. Soil paints as a tool to increase soil awareness among different publics

    NASA Astrophysics Data System (ADS)

    Muggler, Cristine C.

    2013-04-01

    The Earth Sciences Museum Alexis Dorofeef at the Soil Department of the Federal University of Viçosa (UFV), Minas Gerais, Brazil, was opened in 1993 with a goal to sensibilize its public about soils, besides the usual geological approach. Since its opening, many of the guided visits include an activity of painting or modelling with soil materials. Such activities have the aim to familiarize people about the properties of soils, in special, colours, consistencies and textures in a joyful way. The tropical soils of the region offer a wide diversity of colours and textures that wonders and intrigues people in general. With time, some of the visitors as well as the museum team started to make trials how it would be to paint walls with the soil paints. It became a project to develop a social technology since the soil paints could be easily prepared and used at much lower cost than industrial paints. Additionally, to have the house painted offers populations living in the peripheral areas of the town of Viçosa the possibility to increase their quality of life by embellishing the surroundings where they live. After the basic know how was developed, the Museum and other extension groups of UFV started to train people in doing it. A brochure was published and the technique spread rapidly in the region and to other parts of the state and country as well. The workshops on soil paint preparation and use, offered by the Museum are open to a much diversified public: school children, professional painters, farmers of the landless movement, etc. The workshops have been taken as an opportunity to approach soils and its importance to life and environment. They start with questions about how people consider and see soils. From this starting point, soil formation processes and soil properties are introduced and discussed with the group. This is followed by the discussion of landscapes and where the soil materials can be collected and what are the differences to be expected between

  7. On the Wall: Art Students Learn to Paint a Mural

    ERIC Educational Resources Information Center

    Wasley, Paula

    2008-01-01

    In this article, the author describes the Mississippi University for Women's studio art course that teaches students the ins and outs of mural making from inception and design to application of the final glaze. While students in other courses may spend the semester working toward a final exam or paper, this four-and-a-half-week summer course…

  8. On the Wall: Art Students Learn to Paint a Mural

    ERIC Educational Resources Information Center

    Wasley, Paula

    2008-01-01

    In this article, the author describes the Mississippi University for Women's studio art course that teaches students the ins and outs of mural making from inception and design to application of the final glaze. While students in other courses may spend the semester working toward a final exam or paper, this four-and-a-half-week summer course…

  9. Industrial lead paint removal specifications

    SciTech Connect

    Stone, R.C.

    1997-06-01

    The purpose of this paper is to inform the reader as to some of the pertinent rules and regulations promulgated by the Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA) that may effect an industrial lead paint removal project. The paper discusses a recommended schedule of procedures and preparations to be followed by the lead paint removal specification writer when analyzing the possible impact of the project on the environment, the public and workers. Implications of the Clean Air Act, the Clean Water Act and the Resource Conservation and Recovery Act (RCRA) along with hazardous waste handling, manifesting, transporting and disposal procedures are discussed with special emphasis placed as to their impact on the writer and the facility owner. As the rules and regulations are highly complex, the writer has attempted to explain the methodology currently being used in state-of-the-art industrial lead abatement specifications.

  10. Using Temperature Sensitive Paint Technology

    NASA Technical Reports Server (NTRS)

    Hamner, M. P.; Popernack, T. G., Jr.; Owens, L. R.; Wahls, R. A.

    2002-01-01

    New facilities and test techniques afford research aerodynamicists many opportunities to investigate complex aerodynamic phenomena. For example, NASA Langley Research Center's National Transonic Facility (NTF) can hold Mach number, Reynolds number, dynamic pressure, stagnation temperature and stagnation pressure constant during testing. This is important because the wing twist associated with model construction may mask important Reynolds number effects associated with the flight vehicle. Beyond this, the NTF's ability to vary Reynolds number allows for important research into the study of boundary layer transition. The capabilities of facilities such as the NTF coupled with test techniques such as temperature sensitive paint yield data that can be applied not only to vehicle design but also to validation of computational methods. Development of Luminescent Paint Technology for acquiring pressure and temperature measurements began in the mid-1980s. While pressure sensitive luminescent paints (PSP) were being developed to acquire data for aerodynamic performance and loads, temperature sensitive luminescent paints (TSP) have been used for a much broader range of applications. For example, TSP has been used to acquire surface temperature data to determine the heating due to rotating parts in various types of mechanical systems. It has been used to determine the heating pattern(s) on circuit boards. And, it has been used in boundary layer analysis and applied to the validation of full-scale flight performance predictions. That is, data acquired on the same model can be used to develop trends from off design to full scale flight Reynolds number, e.g. to show the progression of boundary layer transition. A discussion of issues related to successfully setting-up TSP tests and using TSP systems for boundary layer studies is included in this paper, as well as results from a variety of TSP tests. TSP images included in this paper are all grey-scale so that similar to

  11. Color signatures in Amorsolo paintings

    NASA Astrophysics Data System (ADS)

    Soriano, Maricor N.; Palomero, Cherry May; Cruz, Larry; Yambao, Clod Marlan Krister; Dado, Julie Mae; Salvador-Campaner, Janice May

    2010-02-01

    We present the results of a two-year project aimed at capturing quantifiable color signatures of oil paintings of Fernando Amorsolo, the Philippine's first National Artists. Color signatures are found by comparing CIE xy measurements of skin color in portraits and ground, sky and foliage in landscapes. The results are compared with results of visual examination and art historical data as well as works done by Amorsolo's contemporaries and mentors.

  12. PCBs in Caulk and Paint

    DTIC Science & Technology

    2010-06-16

    were used in paints ►To enhance structural integrity ►Reduce flammability ►Increase antifungal properties  PCBs imparted heat resistance to the...closed Army ammunition plants has compromised and delayed the decontamination processes. BUILDING STRONG® Field Detection Technologies  Enzyme-linked...hours ► 100% within 48 hours The technology has been field demonstrated at Cape Canaveral Air Station, Fl and Badger Army Ammunition Plant , WI. BUILDING

  13. [Burns caused by paint thinner].

    PubMed

    Benbrahim, A; Jerrah, H; Diouri, M; Bahechar, N; Boukind, E H

    2009-12-31

    Flame deriving from paint thinner is not a rare cause of burns in Morocco and we thus considered it useful to conduct an epidemiological survey of paint thinner flame burns (PTFB) in the National Burns Centre (NBC) in the Ibn-Rochd University Hospital Centre in Casablanca, Morocco. The research covered the 10-month period from September 2007 to June 2008.The aim of our work was to present the characteristic features of such burns in order to prevent them by increasing public knowledge regarding the risks involved in using paint thinner, i.e. burns in particular. During the period in question, we colligated 17 cases of PTFB out of a total number of 356 patients admitted to the NBC for acute burns of all aetiologies. The patients' average was 32 yr and they were nearly all male (16 men/1 woman), with past histories of drug addiction and/or delinquency. They were all of low-level socioeconomic class and lived mainly in shanty towns. The burn was often secondary to street violence (92% of the cases).The mean burn surface area was 23% and the burns were often deep and located mainly in the upper limbs and the trunk.

  14. A New Formulation for the Removal and Remediation of Polychlorinated Biphenyls in Painted Structures

    NASA Technical Reports Server (NTRS)

    Quinn, Jacqueline; Brooks, Kathleen; Geiger, Cherie; Clausen, Christian

    2009-01-01

    This new technology report will describe the laboratory development of a new and innovative solution for the removal and destruction of PCBs found in painted structures or within the binding or caulking material on structures. The technology incorporates a Bimetallic Treatment System (BTS) that extracts and degrades only the PCBs found on the facilities, leaving in most cases the structure virtually unaltered.

  15. 17. Interior view, greenhouse, north wall taken from the ground. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. Interior view, greenhouse, north wall taken from the ground. Stucco-painted white-covered the interior walls in order to seal-off any drafts and to reflect the sunlight entering through the east-facing windows. - John Bartram House & Garden, Greenhouse, 54th Street & LIndbergh Boulevard, Philadelphia, Philadelphia County, PA

  16. KENNEDY SPACE CENTER, FLA. -- A breeding osprey occupies a nest constructed on a speaker pole in the lower parking lot of the KSC Press Site. Eggs have been sighted in the nest. The NASA logo in the background is painted on an outer wall of the 525-foot-tall Vehicle Assembly Building nearby. Known as a fish hawk, the osprey selects sites of opportunity in which to nest -- from trees and telephone poles to rocks or even flat ground. In North America, it is found from Alaska and Newfoundland to Florida and the Gulf Coast. Osprey nests are found throughout the Kennedy Space Center and surrounding Merritt Island National Wildlife Refuge.

    NASA Image and Video Library

    2004-01-14

    KENNEDY SPACE CENTER, FLA. -- A breeding osprey occupies a nest constructed on a speaker pole in the lower parking lot of the KSC Press Site. Eggs have been sighted in the nest. The NASA logo in the background is painted on an outer wall of the 525-foot-tall Vehicle Assembly Building nearby. Known as a fish hawk, the osprey selects sites of opportunity in which to nest -- from trees and telephone poles to rocks or even flat ground. In North America, it is found from Alaska and Newfoundland to Florida and the Gulf Coast. Osprey nests are found throughout the Kennedy Space Center and surrounding Merritt Island National Wildlife Refuge.

  17. Ultraviolet (UV)-reflective paint with ultraviolet germicidal irradiation (UVGI) improves decontamination of nosocomial bacteria on hospital room surfaces.

    PubMed

    Jelden, Katelyn C; Gibbs, Shawn G; Smith, Philip W; Hewlett, Angela L; Iwen, Peter C; Schmid, Kendra K; Lowe, John J

    2017-06-01

    An ultraviolet germicidal irradiation (UVGI) generator (the TORCH, ClorDiSys Solutions, Inc.) was used to compare the disinfection of surface coupons (plastic from a bedrail, stainless steel, and chrome-plated light switch cover) in a hospital room with walls coated with ultraviolet (UV)-reflective paint (Lumacept) or standard paint. Each surface coupon was inoculated with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus faecalis (VRE), placed at 6 different sites within a hospital room coated with UV-reflective paint or standard paint, and treated by 10 min UVC exposure (UVC dose of 0-688 mJ/cm(2) between sites with standard paint and 0-553 mJ/cm(2) with UV-reflective paint) in 8 total trials. Aggregated MRSA concentrations on plastic bedrail surface coupons were reduced on average by 3.0 log10 (1.8 log10 Geometric Standard Deviation [GSD]) with standard paint and 4.3 log10 (1.3 log10 GSD) with UV-reflective paint (p = 0.0005) with no significant reduction differences between paints on stainless steel and chrome. Average VRE concentrations were reduced by ≥4.9 log10 (<1.2 log10 GSD) on all surface types with UV-reflective paint and ≤4.1 log10 (<1.7 log10 GSD) with standard paint (p < 0.05). At 5 aggregated sites directly exposed to UVC light, MRSA concentrations on average were reduced by 5.2 log10 (1.4 log10 GSD) with standard paint and 5.1 log10 (1.2 log10 GSD) with UV-reflective paint (p = 0.017) and VRE by 4.4 log10 (1.4 log10 GSD) with standard paint and 5.3 log10 (1.1 log10 GSD) with UV-reflective paint (p < 0.0001). At one indirectly exposed site on the opposite side of the hospital bed from the UVGI generator, MRSA concentrations on average were reduced by 1.3 log10 (1.7 log10 GSD) with standard paint and 4.7 log10 (1.3 log10 GSD) with UV-reflective paint (p < 0.0001) and VRE by 1.2 log10 (1.5 log10 GSD) with standard paint and 4.6 log10 (1.1 log10 GSD) with UV-reflective paint (p < 0.0001). Coating hospital

  18. Paint Pavement Marking Performance Prediction Model That Includes the Impacts of Snow Removal Operations

    DTIC Science & Technology

    2011-03-01

    Hypothesized that snow plows wear down mountain road pavement markings. 2007 Craig et al. -Edge lines degrade slower than center/skip lines 2007...retroreflectivity to create the models. They discovered that paint pavement markings last 80% longer on Portland Cement Concrete than Asphalt Concrete at low AADT...retroreflectivity, while yellow markings lost 21%. Lu and Barter attributed the sizable degradation to snow removal, sand application, and studded

  19. Association of Phosphatidylinositol Kinase, Phosphatidylinositol Monophosphate Kinase, and Diacylglycerol Kinase with the Cytoskeleton and F-Actin Fractions of Carrot (Daucus carota L.) Cells Grown in Suspension Culture : Response to Cell Wall-Degrading Enzymes.

    PubMed

    Tan, Z; Boss, W F

    1992-12-01

    Phosphatidylinositol kinase (PI), phosphatidylinositol monophosphate (PIP) kinase, and diacylglycerol (DAG) kinase activities were detected in the cytoskeletal fraction isolated from microsomes and plasma membranes of carrot (Daucus carota L.) cells grown in suspension culture. The lipid kinase activities were associated with the actin filament fraction (F-actin fraction) isolated from the cytoskeleton. The PI and PIP kinase activity in the F-actin fraction significantly increased after cells were treated with Driselase, a mixture of cell wall-degrading enzymes; however, the DAG kinase activity in the F-actin fraction was unaffected by the Driselase treatment. These data indicate that at least one form of PI, PIP, and DAG kinase preferentially associates with actin filaments and/or actin binding proteins and that cytoskeletal-associated PI and PIP kinase activities can change in response to external stimulation.

  20. Identification of geometrical shapes in paintings and its application to demonstrate the foundations of geometry in 1650 B.C.

    PubMed

    Papaodysseus, Constantin; Exarhos, Mihalis; Panagopoulos, Thanasis; Triantafillou, Constantin; Roussopoulos, George; Pantazi, Afroditi; Loumos, Vassili; Fragoulis, Dimitrios; Doumas, Christos

    2005-07-01

    In this paper, an original general methodology is introduced to establish whether a handmade shape corresponds to a given geometrical prototype. Using this methodology, one can decide if an artist had the intention of drawing a specific mathematical prototype or not. This analysis is applied to the 1650 B.C. wall paintings from the prehistoric settlement on Thera, and inferences of great archaeological and historical importance are made. In particular, strong evidence is obtained suggesting that the spirals depicted on the wall paintings correspond to linear (Archimedes) spirals, certain shapes correspond to canonical 48-gon and 32-gon, while other shapes correspond to parts of ellipses. It seems that the presented wall paintings constitute the earliest archaeological findings on which these geometrical patterns appear with such remarkable accuracy.

  1. Ejecta production mechanisms on painted surfaces

    NASA Astrophysics Data System (ADS)

    Bariteau, Muriel; Mandeville, Jean-Claude; Schäfer, Frank

    2001-10-01

    Painted surfaces are frequently used on space vehicles, whether on satellites or on rocket bodies. A bibliographic research allows us to evaluate the painted surfaces in orbit at about 63000 m2. The observation of impacts on painted surfaces of the LDEF satellite shows that the total ejected mass is large. However, no description of hypervelocity impact tests on painted surfaces has been found in the literature. An ejecta model has been previously developed at ONERA/DESP. This model is applicable for hypervelocity impacts on homogeneous ductile targets, homogeneous brittle targets and solar cells. The objective of this work is to extend this model to the case of painted surfaces. Consequently, impact pictures on painted surfaces of LDEF were analysed and some laboratory impact tests were performed at the Ernst-Mach-Institut, in Freiburg, under an ESA contract.

  2. Robotic sensors for aircraft paint stripping

    NASA Astrophysics Data System (ADS)

    Weniger, Richard J.

    1990-10-01

    Aircraft of all types need to have paint routinely removed from their outer surfaces. Any method needs to be controlled to remove all the paint and not damage the surface of the aircraft. Human operators get bored with the monotonous task of stripping paint from an aircraft and thus do not control the process very well. This type of tedious operation tends itself to robotics. A robot that strips paint from aircraft needs to have feedback as to the state of the stripping process, its location in respect to the aircraft, and the availability of stripping material. This paper describes the sensors used on the paint stripping robot being developed for the United States Air Force's Manufacturing Technology Program. Particular attention is given to the paint sensor which is the feedback element for determining the state of the stripping process.

  3. Vision-controlled paint spray optimization

    NASA Astrophysics Data System (ADS)

    Ettinger, Gary; Christian, Donald J.

    1992-04-01

    This paper is a case history of spray paint optimization system based on machine vision technology in a factory automation application. The system is implemented as an industrial control for a reciprocating electrostatic sprayer used for priming and painting of armor plate for military ground vehicles. Incoming plates are highly variable in size, shape, and orientation, and are processes in very small production lots. A laser imager is used to digitize visual cross sections of each plate one line at a time. The raster lines are then assembled into a two dimensional image and processed. The spray pattern is optimized for precise paint coverage with minimum overspray. The paint optimizer system has yielded a measured 25 percent savings in bulk paint use, resulting in less booth and equipment maintenance, reduced paint fumes in the atmosphere, and reduced waste disposal, and now has several months of successful production history.

  4. 24 CFR 35.140 - Prohibited methods of paint removal.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... and Urban Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES General Lead-Based Paint Requirements and Definitions for All Programs. § 35.140 Prohibited methods of paint removal. The following methods shall not be used to remove paint that is, or may be, lead-based paint:...

  5. 24 CFR 35.140 - Prohibited methods of paint removal.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... and Urban Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES General Lead-Based Paint Requirements and Definitions for All Programs. § 35.140 Prohibited methods of paint removal. The following methods shall not be used to remove paint that is, or may be, lead-based paint:...

  6. 24 CFR 35.140 - Prohibited methods of paint removal.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... and Urban Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES General Lead-Based Paint Requirements and Definitions for All Programs. § 35.140 Prohibited methods of paint removal. The following methods shall not be used to remove paint that is, or may be, lead-based paint:...

  7. 24 CFR 35.140 - Prohibited methods of paint removal.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... and Urban Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES General Lead-Based Paint Requirements and Definitions for All Programs. § 35.140 Prohibited methods of paint removal. The following methods shall not be used to remove paint that is, or may be, lead-based paint:...

  8. 24 CFR 35.140 - Prohibited methods of paint removal.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... and Urban Development LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES General Lead-Based Paint Requirements and Definitions for All Programs. § 35.140 Prohibited methods of paint removal. The following methods shall not be used to remove paint that is, or may be, lead-based paint:...

  9. 24 CFR 3280.814 - Painting of wiring.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 5 2014-04-01 2014-04-01 false Painting of wiring. 3280.814... Painting of wiring. During painting or staining of the manufactured home, it shall be permitted to paint... cable. Some arrangement, however, shall be made so that no paint shall be applied to the...

  10. 24 CFR 3280.814 - Painting of wiring.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Painting of wiring. 3280.814... Painting of wiring. During painting or staining of the manufactured home, it shall be permitted to paint... cable. Some arrangement, however, shall be made so that no paint shall be applied to the...

  11. 24 CFR 3280.814 - Painting of wiring.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 5 2011-04-01 2011-04-01 false Painting of wiring. 3280.814... Painting of wiring. During painting or staining of the manufactured home, it shall be permitted to paint... cable. Some arrangement, however, shall be made so that no paint shall be applied to the...

  12. 24 CFR 3280.814 - Painting of wiring.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Painting of wiring. 3280.814... Painting of wiring. During painting or staining of the manufactured home, it shall be permitted to paint... cable. Some arrangement, however, shall be made so that no paint shall be applied to the...

  13. 24 CFR 3280.814 - Painting of wiring.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 5 2013-04-01 2013-04-01 false Painting of wiring. 3280.814... Painting of wiring. During painting or staining of the manufactured home, it shall be permitted to paint... cable. Some arrangement, however, shall be made so that no paint shall be applied to the...

  14. Paint Scaler. Innovative Technology Summary Report

    SciTech Connect

    2000-06-01

    The Paint Scaler can collect paint samples quickly and efficiently for lab analysis. The Rotary Hammer Drill is a 24-V battery operated, 3/4-in. rotary hammer drill. When used with an optional chipping adapter, the Bosch Rotary Hammer Drill can be used to perform chipping and chiseling tasks such as paint removal from either concrete or metal surfaces. It is ultra-compact, lightweight with an ergonomic balanced grip. The battery operation gives the operator more flexibility during sampling activities.

  15. The Future of Aircraft Paint Removal Methods

    DTIC Science & Technology

    1989-09-01

    blast, abrasives , sodium bicarbonate blast, grit blast, chemicals 8) Flash lamp, laser, C02 pellet blasting, walnut shells, glass bead blasting...presence of paint dust or residual chemicals, and can 4 cause damage to the aircraft’s surface when the abrasive cuts through the paint layers and...called beads, are propelled by compressed air against a painted surface (56:1). The beL i’s sharpened edges serve as an abrasive to shatter and dislodge

  16. Effect analysis of oil paint on the space optical contamination

    NASA Astrophysics Data System (ADS)

    Lu, Chun-lian; Lv, He; Han, Chun-xu; Wei, Hai-Bin

    2013-08-01

    The space contamination of spacecraft surface is a hot topic in the spacecraft environment project and environment safeguard for spacecraft. Since the 20th century, many American satellites have had malfunction for space contamination. The space optical systems are usually exposed to the external space environment. The particulate contamination of optical systems will degrade the detection ability. We call the optical damage. It also has a bad influence on the spectral imaging quality of the whole system. In this paper, effects of contamination on spectral imaging were discussed. The experiment was designed to observe the effect value. We used numeral curve fitting to analyze the relationship between the optical damage factor (Transmittance decay factor) and the contamination degree of the optical system. We gave the results of six specific wavelengths from 450 to 700nm and obtained the function of between the optical damage factor and contamination degree. We chose three colors of oil paint to be compared. Through the numeral curve fitting and processing data, we could get the mass thickness for different colors of oil paint when transmittance decreased to 50% and 30%. Some comparisons and research conclusions were given. From the comparisons and researches, we could draw the conclusions about contamination effects of oil paint on the spectral imaging system.

  17. Novel Applications of the Er:YAG Laser Cleaning of Old Paintings

    NASA Astrophysics Data System (ADS)

    Andreotti, A.; Bracco, P.; Colombini, M. P.; deCruz, A.; Lanterna, G.; Nakahara, K.; Penaglia, F.

    This chapter focuses on the use of Er:YAG laser cleaning technique for the removal of unwanted and/or degraded materials both from a large series of reference standards (overpainting, varnishes, patinas, and restoration materials) which simulate the layering of old paintings, and also examples from old paintings. A series of diagnostic controls (optical microscopy, SEM, FT-IR, GC-MS, and topographic techniques) were designed to study the effects of the laser radiation on the surface components, including morphological, optical, and chemical examination. The most significant results show that an effective thin-layer-removal of about 90% is obtained by submitting the painted surfaces to the laser exposure, while the rest of cleaning is rapidly accomplished in safety by applying mild solvents or aqueous methods. Consequently, possible interference with the original substrate can be noticeably minimized. No degradation compound induced by laser energy was formed. The laser cleaning procedure applied on an oil painting canvas "Morte di Adone" (seventeenth century), and on a panel tempera painting "San Nicola e San Giusto" of Domenico di Michelino (fifteenth century) shows that the surfaces cleaned by this system exhibit a morphology quite similar to that obtained by traditional cleaning methods.

  18. THE HAZARDS OF PAINTING AND VARNISHING 1965

    PubMed Central

    Piper, Robert

    1965-01-01

    A review of paint hazards is made, giving brief descriptions of methods of application in use in 1965, of paint usage according to resin base, and of paint ingredients. The most interesting and complex of these are the resin bases, which have much in common with plastics. Reference is made to some of the many minor ingredients. The problem of keeping abreast of the possible toxic effects, so that paint manufacturers and their customers may be warned and protected, will be clear. PMID:5836564

  19. Chromate concentration bias in primer paint particles.

    PubMed

    LaPuma, P T; Fox, J M; Kimmel, E C

    2001-06-01

    Chromate-containing primer paints are used to prevent corrosion on metal surfaces. Chromate contains hexavalent chromium (Cr6+), a human carcinogen. The objective of this research was to determine if there is a bias in the fraction of chromate found in various particle sizes generated during primer painting operations. A solvent-based, aviation primer paint was sprayed using a high-volume, low-pressure spray gun. Paint particles were collected and separated by size with seven-stage cascade impactors. It was determined that particles with a mass aerodynamic diameter < 2.0 microm contained significantly less Cr6+ per dry weight of paint than particles > 2.0 microm (P < 0.001). The median concentration of Cr6+ in particles < 2.0 microm is 18 micro g of Cr/mg of dry paint and the median concentration for particles > 2.0 microm is 70 microg of Cr/mg of dry paint. The mixed paint contains 18.75% strontium chromate, which equates to a ratio of 67 microg of Cr/mg of dry paint. Particles > 2.0 microm are more likely to impact in the upper tracheobronchial regions of the lung where mucociliary clearance is relatively rapid. Additionally, chromate emissions from spraying operations may be overestimated because larger particles, which are more easily trapped on an air filter, contain more chromate than the smaller particles, which are more likely to bypass an air filter.

  20. Structural and mechanical properties of "peelable" organoaqueous dispersions with partially hydrolyzed poly(vinyl acetate)-borate networks: applications to cleaning painted surfaces.

    PubMed

    Natali, Irene; Carretti, Emiliano; Angelova, Lora; Baglioni, Piero; Weiss, Richard G; Dei, Luigi

    2011-11-01

    The preparation and structural characterization of a family of viscoelastic dispersions of borate cross-linked, 80% hydrolyzed poly(vinyl acetate) (80PVAc) in aqueous-organic liquids are presented. Correlations between mechanical properties (from rheological measurements) and the degree and nature of cross-linking (from (11)B NMR spectroscopy) are reported, and the results are used to assess their potential as low-impact cleaning agents for the surfaces of paintings. Because the dispersions can be prepared at room temperature by simple procedures from readily available materials and can contain up to 50% (w/w) of an organic liquid, they offer important advantages over previously described cleaning agents that are based on fully hydrolyzed PVAc (i.e., poly(vinyl alcohol). The mechanical properties of the various aqueous-organic dispersions, as determined quantitatively by rheological investigations and qualitatively by their ease of removal from a solid surface (i.e., the so-called "peel-off" ability) have been tuned systematically by varying the amount of organic liquid, its structure, and the concentrations of borax and 80PVAc. The (11)B NMR studies demonstrate that the concentration of borate ions actively participating in cross-linking increases significantly with the amount of organic liquid in the mixture. The degree of cross-linking remains constant when the 80PVAc and borax concentrations are varied, as long as their ratios are kept constant. Some of the 80PVAc-borax dispersions have been tested successfully as cleaning agents on the surface of a 16th-17th century oil-on-wood painting by Lodovico Cardi, "Il Cigoli", that was covered by a brown patina and on the surface of a Renaissance wall painting by Vecchietta in Santa Maria della Scala, Siena, Italy, that had a degraded polyacrylate coating from a previous conservation treatment.