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Sample records for reduced residual arabinose

  1. A phosphodiester bridge between two arabinose residues as a structural element of an extracellular glycoprotein of Volvox carteri.

    PubMed

    Holst, O; Christoffel, V; Fründ, R; Moll, H; Sumper, M

    1989-05-01

    The sulphated glycoprotein SSG 185 is the monomeric precursor of a highly aggregated structural element in the extracellular matrix of the multicellular green alga Volvox carteri. A phosphodiester of arabinose was isolated from a saccharide fragment of SSG 185. The structure of this phosphodiester was investigated by methylation analysis, 13C-NMR, photometric methods and enzymatic assays and identified as D-Araiota-5-phospho-5-D-Araiota. The function of this phosphodiester bridge as a crosslink of different carbohydrate chains in SSG 185 is discussed. PMID:2714288

  2. Virulence Gene Regulation by l-Arabinose in Salmonella enterica

    PubMed Central

    López-Garrido, Javier; Puerta-Fernández, Elena; Cota, Ignacio; Casadesús, Josep

    2015-01-01

    Invasion of the intestinal epithelium is a critical step in Salmonella enterica infection and requires functions encoded in the gene cluster known as Salmonella Pathogenicity Island 1 (SPI-1). Expression of SPI-1 genes is repressed by l-arabinose, and not by other pentoses. Transport of l-arabinose is necessary to repress SPI-1; however, repression is independent of l-arabinose metabolism and of the l-arabinose-responsive regulator AraC. SPI-1 repression by l-arabinose is exerted at a single target, HilD, and the mechanism appears to be post-translational. As a consequence of SPI-1 repression, l-arabinose reduces translocation of SPI-1 effectors to epithelial cells and decreases Salmonella invasion in vitro. These observations reveal a hitherto unknown role of l-arabinose in gene expression control and raise the possibility that Salmonella may use L-arabinose as an environmental signal. PMID:25991823

  3. L-arabinose fermenting yeast

    DOEpatents

    Zhang, Min; Singh, Arjun; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric; Suominen, Pirkko

    2010-12-07

    An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. Methods of producing ethanol include utilizing these modified yeast strains. ##STR00001##

  4. L-arabinose fermenting yeast

    SciTech Connect

    Zhang, Min; Singh, Arjun; Suominen, Pirkko; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric

    2014-09-23

    An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. A yeast strain engineered to metabolize arabinose through a novel pathway is also disclosed. Methods of producing ethanol include utilizing these modified yeast strains.

  5. L-arabinose fermenting yeast

    SciTech Connect

    Zhang, Min; Singh, Arjun; Suominen, Pirkko; Knoshaug, Eric; Franden, Mary Ann; Jarvis, Eric

    2013-02-12

    An L-arabinose utilizing yeast strain is provided for the production of ethanol by introducing and expressing bacterial araA, araB and araD genes. L-arabinose transporters are also introduced into the yeast to enhance the uptake of arabinose. The yeast carries additional genomic mutations enabling it to consume L-arabinose, even as the only carbon source, and to produce ethanol. A yeast strain engineered to metabolize arabinose through a novel pathway is also disclosed. Methods of producing ethanol include utilizing these modified yeast strains.

  6. Microbial production of xylitol from xylose and L-arabinose: conversion of L-arabitol to xylitol using bacterial oxidoreductases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microbial production of xylitol, using hemicellulosic biomass such as agricultural residues, is becoming more attractive for reducing its manufacturing cost. L-arabitol is a particular problem to xylitol production from hemicellulosic hydrolyzates that contain both xylose and L-arabinose because it...

  7. Fractionation of sugar beet pulp into pectin, cellulose, and arabinose by arabinases combined with ultrafiltration

    SciTech Connect

    Spangnuolo, M.; Crecchio, C.; Pizzigallo, M.D.R.; Ruggiero, P.

    1999-09-20

    Incubation of beet pulp with two arabinases ({alpha}-L-arabinofuranosidase and endo-arabinase), used singularly or in combination at different units of activity per gram of beet pulp, caused the hydrolysis of arabinasn, which produced a hydrolyzate consisting mainly of arabinose. Pectin and a residue enriched with cellulose were subsequently separated from the incubation mixture. The best enzymatic hydrolysis results were obtained when 100 U/g of beet pulp of each enzyme worked synergistically with yields of 100% arabinose and 91.7% pectin. These yields were higher than those obtained with traditional chemical hydrolysis. The pectin fraction showed a low content of neutral sugar content and the cellulose residue contained only a small amount of pentoses. Semicontinuous hydrolysis with enzyme recycling in an ultrafiltration unit was also carried out to separate arabinose, pectin, and cellulose from beet pulp in 7 cycles of hydrolysis followed by ultrafiltration. The yields of separation were similar to those obtained in batch experiments, with an enzyme consumption reduced by 3.5 times and some significant advantages over batch processes.

  8. Regulation of L-arabinose transport in Salmonella typhimurium LT2.

    PubMed

    Lee, J H; Russo, R J; Heffernan, L; Wilcox, G

    1982-01-01

    The inducible L-arabinose transport system was characterized in Salmonella typhimurium LT2. Only one L-arabinose transport system with a Km of 2 X 10(-4) M was identified. The results suggested that araE may be the only gene which codes for L-arabinose transport activity under the conditions tested. An araE-lac fusion strain was used to study the induction of the araE gene. No araE expression was detected when the L-arabinose concentration was lower than 1 mM. The expression of araE reached a maximum in the presence of 50 mM L-arabinose, and was significantly reduced in the presence of 50 mM L-arabinose, and was significantly reduced in the presence of D-glucose. Expression of the araBAD and araE genes was coordinately regulated. The concentration of L-arabinose that allowed maximum araBAD gene expression was 50-fold lower in an araE+ strain compared to an araE strain. PMID:6283309

  9. ECONOMICALLY OPTIMAL NITROGEN RATE REDUCES SOIL RESIDUAL NITRATE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Practices that minimize post-harvest residual soil NO3-N (RSN) can reduce N loss to the environment. Our objectives were to determine if the RSN after corn (Zea mays L.) harvest can be reduced if N fertilizer is applied at the economically optimal N rate (EONR) as compared to current producers' prac...

  10. A novel transcriptional regulator of L-arabinose utilization in human gut bacteria

    PubMed Central

    Chang, Changsoo; Tesar, Christine; Li, Xiaoqing; Kim, Youngchang; Rodionov, Dmitry A.; Joachimiak, Andrzej

    2015-01-01

    Carbohydrate metabolism plays a crucial role in the ecophysiology of human gut microbiota. Mechanisms of transcriptional regulation of sugar catabolism in commensal and prevalent human gut bacteria such as Bacteroides thetaiotaomicron remain mostly unknown. By a combination of bioinformatics and experimental approaches, we have identified an NrtR family transcription factor (BT0354 in B. thetaiotaomicron, BtAraR) as a novel regulator controlling the arabinose utilization genes. L-arabinose was confirmed to be a negative effector of BtAraR. We have solved the crystal structures of the apo and L-arabinose-bound BtAraR proteins, as well as the complex of apo-protein with a specific DNA operator. BtAraR forms a homodimer with each subunit comprised of the ligand-binding Nudix hydrolase-like domain and the DNA-binding winged-helix-turn-helix (wHTH) domain. We have identified the residues involved in binding of L-arabinose and recognition of DNA. The majority of these residues are well conserved in the AraR orthologs in Bacteroidetes. In the structure of the BtAraR–DNA complex, we found the unique interaction of arginine intercalating its guanidinum moiety into the base pair stacking of B-DNA. L-arabinose binding induces movement of wHTH domains, resulting in a conformation unsuitable for DNA binding. Our analysis facilitates reconstruction of the metabolic and regulatory networks involved in carbohydrate utilization in human gut Bacteroides. PMID:26438537

  11. Residues recycling: Reducing costs and helping the environment

    NASA Astrophysics Data System (ADS)

    Venancio, Luis C. A.; Souza, José Antonio Silva; Macedo, Emanuel Negrão; Quaresma, João Nazareno N.; Paiva, Antonio Ernandes M.

    2010-09-01

    The aluminum production chain from bauxite to primary aluminum includes refining using the Bayer process, and smelting through electrolysis. This production chain produces two main solid residues, red mud at the refinery and spent pot lining at the smelter. The use of these residues as raw material for other industrial processes can save large amounts of energy, reduce the overall environmental impact, and even improve the emissions of other processes. This paper shows the results of ten years of co-processing of spent pot lining in the cement industry in Brazil and the efforts to develop technologies to reduce the reactivity and use the red mud as raw material for several different processes. This approach, although engineering intensive, can reduce C02 emissions and save huge amounts of wasted energy in transport and processing when compared with dedicated recycling or neutralizing processes.

  12. Protective effects of L-arabinose in high-carbohydrate, high-fat diet-induced metabolic syndrome in rats

    PubMed Central

    Hao, Lei; Lu, Xiaoling; Sun, Min; Li, Kai; Shen, Lingmin; Wu, Tao

    2015-01-01

    Background L-Arabinose is a non-caloric sugar, which could affect glucose and lipid metabolism and suppress obesity. However, few reports have described the effect of L-arabinose in metabolic syndrome, a combination of medical disorders that increase the risk of diabetes and cardiovascular disease. Objective This study was conducted to explore the effects of L-arabinose in rats with metabolic syndrome induced by a high-carbohydrate, high-fat (HCHF) diet. Methods After the rat model for metabolic syndrome was successfully established, L-arabinose was administrated by oral gavage for 6 weeks. The biochemical index and histological analysis were measured, and the expression levels of genes related to fatty acid metabolism were analyzed using real-time PCR. Results Following treatment with L-arabinose, metabolic syndrome rats had an obvious reduction in body weight, systolic blood pressure, diastolic blood pressure, fasting blood glucose, triglycerides, total cholesterol, serum insulin, TNF-α, and leptin. Further study showed that treatment with L-arabinose significantly increased the expression of mRNA for hepatic CPT-1α and PDK4, but the expression of mRNA for hepatic ACCα was reduced. Conclusions This work suggests that L-arabinose could lower body weight, Lee's index, and visceral index and improve dyslipidemia, insulin resistance, inflammation, and viscera function, which indicate that it might be a promising candidate for therapies combating metabolic syndrome. PMID:26652604

  13. A novel transcriptional regulator of L-arabinose utilization in human gut bacteria

    DOE PAGESBeta

    Chang, Changsoo; Tesar, Christine; Li, Xiaoqing; Kim, Youngchang; Rodionov, Dmitry A.; Joachimiak, Andrzej

    2015-10-04

    We report that carbohydrate metabolism plays a crucial role in the ecophysiology of human gut microbiota. Mechanisms of transcriptional regulation of sugar catabolism in commensal and prevalent human gut bacteria such as Bacteroides thetaiotaomicron remain mostly unknown. By a combination of bioinformatics and experimental approaches, we have identified an NrtR family transcription factor (BT0354 in B. thetaiotaomicron, BtAraR) as a novel regulator controlling the arabinose utilization genes. L-arabinose was confirmed to be a negative effector of BtAraR. We have solved the crystal structures of the apo and L-arabinose-bound BtAraR proteins, as well as the complex of apo-protein with a specificmore » DNA operator. BtAraR forms a homodimer with each subunit comprised of the ligand-binding Nudix hydrolase-like domain and the DNA-binding winged-helix-turn-helix (wHTH) domain. We have identified the residues involved in binding of L-arabinose and recognition of DNA. The majority of these residues are well conserved in the AraR orthologs in Bacteroidetes. In the structure of the BtAraR–DNA complex, we found the unique interaction of arginine intercalating its guanidinum moiety into the base pair stacking of B-DNA. L-arabinose binding induces movement of wHTH domains, resulting in a conformation unsuitable for DNA binding. Furthermore, our analysis facilitates reconstruction of the metabolic and regulatory networks involved in carbohydrate utilization in human gut Bacteroides.« less

  14. A novel transcriptional regulator of L-arabinose utilization in human gut bacteria

    SciTech Connect

    Chang, Changsoo; Tesar, Christine; Li, Xiaoqing; Kim, Youngchang; Rodionov, Dmitry A.; Joachimiak, Andrzej

    2015-10-04

    We report that carbohydrate metabolism plays a crucial role in the ecophysiology of human gut microbiota. Mechanisms of transcriptional regulation of sugar catabolism in commensal and prevalent human gut bacteria such as Bacteroides thetaiotaomicron remain mostly unknown. By a combination of bioinformatics and experimental approaches, we have identified an NrtR family transcription factor (BT0354 in B. thetaiotaomicron, BtAraR) as a novel regulator controlling the arabinose utilization genes. L-arabinose was confirmed to be a negative effector of BtAraR. We have solved the crystal structures of the apo and L-arabinose-bound BtAraR proteins, as well as the complex of apo-protein with a specific DNA operator. BtAraR forms a homodimer with each subunit comprised of the ligand-binding Nudix hydrolase-like domain and the DNA-binding winged-helix-turn-helix (wHTH) domain. We have identified the residues involved in binding of L-arabinose and recognition of DNA. The majority of these residues are well conserved in the AraR orthologs in Bacteroidetes. In the structure of the BtAraR–DNA complex, we found the unique interaction of arginine intercalating its guanidinum moiety into the base pair stacking of B-DNA. L-arabinose binding induces movement of wHTH domains, resulting in a conformation unsuitable for DNA binding. Furthermore, our analysis facilitates reconstruction of the metabolic and regulatory networks involved in carbohydrate utilization in human gut Bacteroides.

  15. Metabolism of L-arabinose in plants.

    PubMed

    Kotake, Toshihisa; Yamanashi, Yukiko; Imaizumi, Chiemi; Tsumuraya, Yoichi

    2016-09-01

    L-Arabinose (L-Ara) is a plant-specific sugar accounting for 5-10 % of cell wall saccharides in Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa). L-Ara occurs in pectic arabinan, rhamnogalacturonan II, arabinoxylan, arabinogalactan-protein (AGP), and extensin in the cell walls, as well as in glycosylated signaling peptides like CLAVATA3 and small glycoconjugates such as quercetin 3-O-arabinoside. This review focuses on recent advances towards understanding the generation of L-Ara and the metabolism of L-Ara-containing molecules in plants. PMID:27220955

  16. Economically optimal nitrogen rate reduces soil residual nitrate.

    PubMed

    Hong, Nan; Scharf, Peter C; Davis, J Glenn; Kitchen, Newell R; Sudduth, Kenneth A

    2007-01-01

    Post-harvest residual soil NO(3)-N (RSN) is susceptible to transfer to water resources. Practices that minimize RSN levels can reduce N loss to the environment. Our objectives were (i) to determine if the RSN after corn (Zea mays L.) harvest can be reduced if N fertilizer is applied at the economically optimal N rate (EONR) as compared to current producer practices in the midwestern USA and (ii) to compare RSN levels for N fertilizer rates below, at, and above the EONR. Six experiments were conducted in producer fields in three major soil areas (Mississippi Delta alluvial, deep loess, claypan) in Missouri over 2 yr. Predominant soil great groups were Albaqualfs, Argiudolls, Haplaquolls, and Fluvaquents. At four transects in each field, six treatment N rates from 0 to 280 kg N ha(-1) were applied, the EONR was determined, and the RSN was measured to a 0.9-m depth from five treatment plots. The EONR at sampling sites varied from 49 to 228 kg N ha(-1) depending on site and year. Estimated average RSN at the EONR was 33 kg N ha(-1) in the 0.9-m profile. This was at least 12 kg N ha(-1) lower than RSN at the producers' N rates. The RSN increased with increasing Delta EONR (total N applied - EONR). This relationship was best modeled by a plateau-linear function, with a low RSN plateau at N rates well below the EONR. A linear increase in RSN began anywhere from 65 kg N ha(-1) below the EONR to 20 kg N ha(-1) above the EONR at the three sites with good data resolution near the EONR. Applying N rates in excess of the EONR produced elevated RSN values in all six experiments. Our results suggest that applying the EONR will produce environmental benefits in an economically sound manner, and that continued attempts to develop methods for accurately predicting EONR are justified. PMID:17255622

  17. Heterologous expression and characterization of Bacillus coagulans L-arabinose isomerase.

    PubMed

    Zhou, Xingding; Wu, Jin Chuan

    2012-05-01

    Bacillus coagulans has been of great commercial interest over the past decade owing to its strong ability of producing optical pure L: -lactic acid from both hexose and pentose sugars including L: -arabinose with high yield, titer and productivity under thermophilic conditions. The L: -arabinose isomerase (L-AI) from Bacillus coagulans was heterologously over-expressed in Escherichia coli. The open reading frame of the L-AI has 1,422 nucleotides encoding a protein with 474 amino acid residues. The recombinant L-AI was purified to homogeneity by one-step His-tag affinity chromatography. The molecular mass of the enzyme was estimated to be 56 kDa by SDS-PAGE. The enzyme was most active at 70°C and pH 7.0. The metal ion Mn(2+) was shown to be the best activator for enzymatic activity and thermostability. The enzyme showed higher activity at acidic pH than at alkaline pH. The kinetic studies showed that the K (m), V (max) and k (cat)/K (m) for the conversion of L: -arabinose were 106 mM, 84 U/mg and 34.5 mM(-1)min(-1), respectively. The equilibrium ratio of L: -arabinose to L: -ribulose was 78:22 under optimal conditions. L: -ribulose (97 g/L) was obtained from 500 g/l of L: -arabinose catalyzed by the enzyme (8.3 U/mL) under the optimal conditions within 1.5 h, giving at a substrate conversion of 19.4% and a production rate of 65 g L(-1) h(-1). PMID:22806043

  18. Sugar-metal ion interactions: The coordination behavior of cesium ion with lactose, D-arabinose and L-arabinose

    NASA Astrophysics Data System (ADS)

    Jiang, Ye; Xue, Junhui; Wen, Xiaodong; Zhai, Yanjun; Yang, Limin; Xu, Yizhuang; Zhao, Guozhong; Kou, Kuan; Liu, Kexin; Chen, Jia'er; Wu, Jinguang

    2016-04-01

    The novel cesium chloride-lactose complex (CsCl·C12H22O10 (Cs-Lac), cesium chloride-D-arabinose and L-arabinose complexes (CsCl·C5H10O5, Cs-D-Ara and Cs-L-Ara) have been synthesized and characterized using X-ray diffraction, FTIR, FIR, THz and Raman spectroscopies. Cs+ is 9-coordinated to two chloride ions and seven hydroxyl groups from five lactose molecules in Cs-Lac. In the structures of CsCl-D-arabinose and CsCl-L-arabinose complexes, two kinds of Cs+ ions coexist in the structures. Cs1 is 10-coordinated with two chloride ions and eight hydroxyl groups from five arabinose molecule; Cs2 is 9-coordinated to three chloride ions and six hydroxyl groups from five arabinose molecules. Two coordination modes of arabinose coexist in the structures. α-D-arabinopyranose and α-L-arabinopyranose appear in the structures of Cs-D-Ara and Cs-L-Ara complexes. FTIR and Raman results indicate variations of hydrogen bonds and the conformation of the ligands after complexation. FIR and THz spectra also confirm the formation of Cs-complexes. Crystal structure, FTIR, FIR, THz and Raman spectra provide detailed information on the structure and coordination of hydroxyl groups to metal ions in the cesium chloride-lactose, cesium chloride-D- and L-arabinose complexes.

  19. Utility pump truck; Residual gas problems reduced with innovative equipment

    SciTech Connect

    Not Available

    1988-04-01

    Residual natural gas trapped in the ground after the repair of a distribution-system leak can be a headache for utility employees and customers. The pump truck, a unique approach to removing residual gas, is described in this paper. Natural gas is lighter than air and naturally tends to rise upward and dissipate in the atmosphere. However, pavement, buildings or soil conditions around a leaking pipe often cause gas to be trapped in the ground. In addition to removing trapped gas, the pump truck is used to help pinpoint leaks where the source is difficult to locate because of soil conditions.

  20. Single Zymomonas mobilis strain for xylose and arabinose fermentation

    DOEpatents

    Zhang, M.; Chou, Y.C.; Picataggio, S.K.; Finkelstein, M.

    1998-12-01

    This invention relates to single microorganisms which normally do not ferment pentose sugars which are genetically altered to ferment the pentose sugars, xylose and arabinose, to produce ethanol, and a fermentation process utilizing the same. Examples include Zymomonas mobilis which has been transformed with a combination of E. coli genes for xylose isomerase, xylulokinase, L-arabinose isomerase, L-ribulokinase, L-ribulose 5-phosphate 4-epimerase, transaldolase and transketolase. Expression of added genes are under the control of Z. mobilis promoters. These newly created microorganisms are useful for fermenting glucose, xylose and arabinose, produced by hydrolysis of hemicellulose and cellulose or starch, to produce ethanol. 6 figs.

  1. Single zymomonas mobilis strain for xylose and arabinose fermentation

    DOEpatents

    Zhang, Min; Chou, Yat-Chen; Picataggio, Stephen K.; Finkelstein, Mark

    1998-01-01

    This invention relates to single microorganisms which normally do not ferment pentose sugars which are genetically altered to ferment the pentose sugars, xylose and arabinose, to produce ethanol, and a fermentation process utilizing the same. Examples include Zymomonas mobilis which has been transformed with a combination of E. coli genes for xylose isomerase, xylulokinase, L-arabinose isomerase, L-ribulokinase, L-ribulose 5-phosphate 4-epimerase, transaldolase and transketolase. Expression of added genes are under the control of Z. mobilis promoters. These newly created microorganisms are useful for fermenting glucose, xylose and arabinose, produced by hydrolysis of hemicellulose and cellulose or starch, to produce ethanol.

  2. Improving N credit predictions to reduce residual nitrate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The potential to increase farm profitability and reduce nitrate leaching in Minnesota are huge if the alfalfa N credit was better understood and applied to first-year corn. If the N credit (150 lb/N/ac) were applied to the nearly 250,000 acres of corn following alfalfa in Minnesota each year, 19,000...

  3. Microbial Production of Xylitol from L-arabinose by Metabolically Engineered Escherichia coli

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An Escherichia coli strain, ZUC99(pATX210), which can produce xylitol from L-arabinose at a high yield has been created by introducing a new bioconversion pathway into cells. This pathway consists of three enzymes: L-arabinose isomerase, which converts L-arabinose to L-ribulose; D-psicose 3-epimer...

  4. Roller Burnishing - A Cold Working Tool to Reduce Weld Induced Residual Stress

    SciTech Connect

    John Martin

    2002-02-19

    The possibility of stress corrosion cracking (SCC) in regions of tensile residual stress introduced by weld deposited material has been a concern where environmental effects can reduce component life. Roller burnishing, a form of mechanical cold-working, has been considered as a means of providing for residual stress state improvements. This paper provides a computational evaluation of the roller burnishing process to address the permanent deformation needed to introduce a desirable residual stress state. The analysis uses a series of incrementally applied pressure loadings and finite element methodology to simulate the behavior of a roller burnishing tool. Various magnitudes of applied pressure loadings coupled with different size plates and boundary conditions are examined to assess the degree and depth of the residual compressive stress state after cold working. Both kinematic and isotropic hardening laws are evaluated.

  5. Study on Winding Method to Reduce the Residual Current of Track Type (Oval Type) ZCT

    NASA Astrophysics Data System (ADS)

    Iwasaki, Fumio; Ibe, Masayuki; Ninohei, Koichiro; Okamura, Seiichiro

    ZCT (Zero-phase-sequence Current Transformer) is used widely for the detection of the ground fault current in low or high voltage distribution power line. Especially, the use of pole air switches equipped with ZCT is increasing to prevent the extended accident caused by the ground fault. The accurate detection of low level ground fault is needed from the view of early stage discovery. The internal residual current of ZCT must be small as possible for the detection of low level ground fault. Generally, the magnetic shield around the core of ZCT is used to reduce the internal residual current. Also, the core material and shield effect is related to the reduction of the internal residual current. In this paper, the reducing method of the internal residual current is proposed by using new winding method of the core. In new winding method, the secondary and tertiary windings are provided, and each winding is divided into two or three sections with parallel connection. The leakage magnetic flux caused by the primary current is changed to the cross current in parallel winding. This cross current is used to offset the leakage magnetic flux caused by the primary current. It is observed by the examination that the cross current is effective to reduce the internal residual current without influence to the zero phase current detection.

  6. Simultaneous utilization of glucose, xylose and arabinose in the presence of acetate by a consortium of Escherichia coli strains

    PubMed Central

    2012-01-01

    Background The efficient microbial utilization of lignocellulosic hydrolysates has remained challenging because this material is composed of multiple sugars and also contains growth inhibitors such as acetic acid (acetate). Using an engineered consortium of strains derived from Escherichia coli C and a synthetic medium containing acetate, glucose, xylose and arabinose, we report on both the microbial removal of acetate and the subsequent simultaneous utilization of the sugars. Results In a first stage, a strain unable to utilize glucose, xylose and arabinose (ALS1392, strain E. coli C ptsG manZ glk crr xylA araA) removed 3 g/L acetate within 30 hours. In a subsequent second stage, three E. coli strains (ALS1370, ALS1371, ALS1391), which are each engineered to utilize only one sugar, together simultaneously utilized glucose, xylose and arabinose. The effect of non-metabolizable sugars on the metabolism of the target sugar was minimal. Additionally the deletions necessary to prevent the consumption of one sugar only minimally affected the consumption of a desired sugar. For example, the crr deletion necessary to prevent glucose consumption reduced xylose and arabinose utilization by less than 15% compared to the wild-type. Similarly, the araA deletion used to exclude arabinose consumption did not affect xylose- and glucose-consumption. Conclusions Despite the modest reduction in the overall rate of sugar consumption due to the various deletions that were required to generate the consortium of strains, the approach constitutes a significant improvement in any single-organism approach to utilize sugars found in lignocellulosic hydrolysate in the presence of acetate. PMID:22691294

  7. Sugarcane Post-harvest Residue Retention and Certain Ripener Applications Reduce First and Second Ratoon Yields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Retention of sugarcane (interspecific hybrids of Saccharum spp.) post-harvest residue and certain glyphosate ripener application regimes have independently been shown to reduce yields of the subsequent ratoon crop. The objective of this experiment was to determine the combined effects of post-harve...

  8. Teichuronic acid reducing terminal N-acetylglucosamine residue linked by phosphodiester to peptidoglycan of Micrococcus luteus

    SciTech Connect

    Gassner, G.T.; Dickie, J.P.; Hamerski, D.A.; Magnuson, J.K.; Anderson, J.S. )

    1990-05-01

    Teichuronic acid-peptidoglycan complex isolated from Micrococcus luteus cells by lysozyme digestion in osmotically stabilized medium was treated with mild acid to cleave the linkage joining teichuronic acid to peptidoglycan. This labile linkage was shown to be the phosphodiester which joins N-acetylglucosamine, the residue located at the reducing end of the teichuronic acid, through its anomeric hydroxyl group to a 6-phosphomuramic acid, a residue of the glycan strand of peptidoglycan. {sup 31}P nuclear magnetic resonance spectroscopy of the lysozyme digest of cell walls demonstrated the presence of a phosphodiester which was converted to a phosphomonoester by the conditions which released teichuronic acid from cell walls. Reduction of acid-liberated reducing end groups by NaB{sup 3}H{sub 4} followed by complete acid hydrolysis yielded ({sup 3}H) glucosaminitol from the true reducing end residue of teichuronic acid and ({sup 3}H)glucitol from the sites of fragmentation of teichuronic acid. The amount of N-acetylglucosamine detected was approximately stoichiometric with the amount of phosphate in the complex. Partial fragmentation of teichuronic acid provides an explanation of the previous erroneous identification of the reducing end residue.

  9. Combined glyphosate-ripener and residue blanket stresses reduce ratoon yields in Louisiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Failure to remove the blanket of residue generated during green-cane harvesting and certain glyphosate ripener application regimes have independently been shown to reduce yields of the subsequent ratoon crop of Louisiana’s leading variety LCP 85-384. The objectives of this experiment were to determ...

  10. Concurrent tailoring of fabrication process and interphase layer to reduce residual stresses in metal matrix composites

    NASA Technical Reports Server (NTRS)

    Saravanos, D. A.; Chamis, C. C.; Morel, M.

    1991-01-01

    A methodology is presented to reduce the residual matrix stresses in continuous fiber metal matrix composites (MMC) by optimizing the fabrication process and interphase layer characteristics. The response of the fabricated MMC was simulated based on nonlinear micromechanics. Application cases include fabrication tailoring, interphase tailoring, and concurrent fabrication-interphase optimization. Two composite systems, silicon carbide/titanium and graphite/copper, are considered. Results illustrate the merits of each approach, indicate that concurrent fabrication/interphase optimization produces significant reductions in the matrix residual stresses and demonstrate the strong coupling between fabrication and interphase tailoring.

  11. A Link between Arabinose Utilization and Oxalotrophy in Bradyrhizobium japonicum

    PubMed Central

    Koch, Marion; Delmotte, Nathanaël; Ahrens, Christian H.; Omasits, Ulrich; Schneider, Kathrin; Danza, Francesco; Padhi, Barnali; Murset, Valérie; Braissant, Olivier; Vorholt, Julia A.; Hennecke, Hauke

    2014-01-01

    Rhizobia have a versatile catabolism that allows them to compete successfully with other microorganisms for nutrients in the soil and in the rhizosphere of their respective host plants. In this study, Bradyrhizobium japonicum USDA 110 was found to be able to utilize oxalate as the sole carbon source. A proteome analysis of cells grown in minimal medium containing arabinose suggested that oxalate oxidation extends the arabinose degradation branch via glycolaldehyde. A mutant of the key pathway genes oxc (for oxalyl-coenzyme A decarboxylase) and frc (for formyl-coenzyme A transferase) was constructed and shown to be (i) impaired in growth on arabinose and (ii) unable to grow on oxalate. Oxalate was detected in roots and, at elevated levels, in root nodules of four different B. japonicum host plants. Mixed-inoculation experiments with wild-type and oxc-frc mutant cells revealed that oxalotrophy might be a beneficial trait of B. japonicum at some stage during legume root nodule colonization. PMID:24463964

  12. Microbial conversion of L-arabinose to xylitol by coexpression of L-arabinose isomerase, D-tagatose 3-epimerase, and L-xylulose reductase in Escherichia coli

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A microbial strain has been developed that can produce xylitol from L-arabinose at a high yield by transforming Escherichia coli with a new xylitol biosynthetic pathway consisting of L-arabinose isomerase, D-tagatose 3-epimerase, and L-xylulose reductase. An E. coli strain that heterologously expre...

  13. The effect of various frequencies of ultrasonic cleaner in reducing residual monomer in acrylic resin.

    PubMed

    Charasseangpaisarn, Taksid; Wiwatwarrapan, Chairat

    2015-12-01

    Monomer remaining in denture base acrylic can be a major problem because it may cause adverse effects on oral tissue and on the properties of the material. The purpose of this study was to compare the effect of various ultrasonic cleaner frequencies on the amount of residual monomer in acrylic resin after curing. Forty-two specimens each of Meliodent heat-polymerized acrylic resin (M) and Unifast Trad Ivory auto-polymerized acrylic resin (U) were prepared according to their manufacturer's instructions and randomly divided into seven groups: Negative control (NC); Positive control (PC); and five ultrasonic treatment groups: 28 kHz (F1), 40 kHz (F2), 60 kHz (F3) (M=10 min, U=5 min), and 28 kHz followed by 60 kHz (F4: M=5 min per frequency, U=2.5 min per frequency, and F5: M=10 min followed by 5 min per frequency, U=5 min followed by 2.5 min per frequency). Residual monomer was determined by HPLC following ISO 20795-1. The data were analyzed by One-way ANOVA and Tukey HSD. There was significantly less residual monomer in the auto-polymerized acrylic resin in all ultrasonic treatment groups and the PC group than that of the NC group (p<0.05). However, the amount of residual monomer in group F3 was significantly higher than that of the F1, F4, and PC groups (p<0.05). In contrast, ultrasonic treatment did not reduce the amount of residual monomer in heat-polymerized acrylic resin (p>0.05). The amount of residual monomer in heat-polymerized acrylic resin was significantly lower than that of auto-polymerized acrylic resin. In conclusion, ultrasonic treatment at low frequencies is recommended to reduce the residual monomer in auto-polymerized acrylic resin and this method is more practical in a clinical situation than previously recommended methods because of reduced chairside time. PMID:26190059

  14. Citrus co-products as technological strategy to reduce residual nitrite content in meat products.

    PubMed

    Viuda-Martos, M; Fernández-López, J; Sayas-Barbera, E; Sendra, E; Navarro, C; Pérez-Alvarez, J A

    2009-10-01

    Sodium or potassium nitrite is widely used as a curing agent in cured meat products because it inhibits outgrowth and neurotoxin formation by Clostridium botulinum, delays the development of oxidative rancidity, develops the characteristic flavor of cured meats, and reacts with myoglobin and stabilizes the red meat color. As soon as nitrite is added in the meat formulation, it starts to disappear and the nitrite that has not reacted with myoglobin and it is available corresponds to residual nitrite level. Health concerns relating to the use of nitrates and nitrites in cured meats (cooked and dry cured) trend toward decreased usage to alleviate the potential risk to the consumers from formation of carcinogenic compounds. Recently, some new ingredients principally agro-industrial co-products in general and those from the citrus industry in particular (albedo [with different treatments], dietetic fiber obtained from the whole co-product, and washing water used in the process to obtain the dietetic fiber) are seen as good sources of bio-compounds that may help to reduce the residual nitrite level in meat products. From these co-products, citrus fiber shows the highest potential to reduce the residual nitrite level, followed by the albedo and finally the washing water. The aim of this article is to describe the latest advances concerning the use of citrus co-products in meat products as a potential ingredient to reduce the nitrite level. PMID:19799678

  15. THE FUNDAMENTAL METALLICITY RELATION REDUCES TYPE Ia SN HUBBLE RESIDUALS MORE THAN HOST MASS ALONE

    SciTech Connect

    Hayden, Brian T.; Garnavich, Peter M.; Gupta, Ravi R.; Sako, Masao; Mannucci, Filippo; Nichol, Robert C.

    2013-02-20

    Type Ia supernova Hubble residuals have been shown to correlate with host galaxy mass, imposing a major obstacle for their use in measuring dark energy properties. Here, we calibrate the fundamental metallicity relation (FMR) of Mannucci et al. for host mass and star formation rates measured from broadband colors alone. We apply the FMR to the large number of hosts from the SDSS-II sample of Gupta et al. and find that the scatter in the Hubble residuals is significantly reduced when compared with using only stellar mass (or the mass-metallicity relation) as a fit parameter. Our calibration of the FMR is restricted to only star-forming galaxies and in the Hubble residual calculation we include only hosts with log(SFR) > - 2. Our results strongly suggest that metallicity is the underlying source of the correlation between Hubble residuals and host galaxy mass. Since the FMR is nearly constant between z = 2 and the present, use of the FMR along with light-curve width and color should provide a robust distance measurement method that minimizes systematic errors.

  16. Enhanced Atrazine Degradation: Evidence for Reduced Residual Weed Control and A Method for Identifying Adapted Soils and Predicting Herbicide Persistence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soilborn bacteria with novel metabolic abilities have been linked with enhanced atrazine degradation and complaints of reduced residual weed control in soils with an s-triazine use history. However, no field study has verified that enhanced degradation reduces atrazine’s residual weed control. The...

  17. Reduced residual conduction gaps and favourable outcome in contact force-guided circumferential pulmonary vein isolation

    PubMed Central

    Itoh, Taihei; Kimura, Masaomi; Tomita, Hirofumi; Sasaki, Shingo; Owada, Shingen; Horiuchi, Daisuke; Sasaki, Kenichi; Ishida, Yuji; Kinjo, Takahiko; Okumura, Ken

    2016-01-01

    Aims Although contact force (CF)-guided circumferential pulmonary vein isolation (CPVI) for paroxysmal atrial fibrillation (PAF) is useful, AF recurrence at long-term follow-up still remains to be resolved. The purpose of this study was to assess safety and efficacy of CF-guided CPVI and to compare residual conduction gaps during CPVI and long-term outcome between the conventional (non-CF-guided) and the CF-guided CPVI. Methods and results We studied the 50 consecutive PAF patients undergoing CPVI by a ThermoCool EZ Steer catheter (conventional group, mean age 61 ± 10 years) and the other 50 consecutive PAF patients by a ThermoCool SmartTouch catheter (CF group, 65 ± 11 years). The procedure parameters and residual conduction gaps during CPVI, and long-term outcome for 12 months were compared between the two groups. Circumferential pulmonary vein isolation was successfully accomplished without any major complications in both groups. Total procedure and total fluoroscopy times were both significantly shorter in the CF group than in the conventional group (160 ± 30 vs. 245 ± 61 min, P < 0.001, and 17 ± 8 vs. 54 ± 27 min, P < 0.001, respectively). Total number of residual conduction gaps was significantly less in the CF group than in the conventional group (2.7 ± 1.7 vs. 6.3 ± 2.7, P < 0.05). The AF recurrence-free rates after CPVI during 12-month follow-up were 96% (48/50) in the CF group and 82% (41/50) in the conventional group (P = 0.02 by log rank test). Multivariate Cox regression analysis further supported this finding. Conclusion Contact force-guided CPVI is safe and more effective in reducing not only the procedure time but also the AF recurrence than the conventional CPVI, possibly due to reduced residual conduction gaps during CPVI procedure. PMID:26346921

  18. Epistatic Interactions in the Arabinose Cis-Regulatory Element

    PubMed Central

    Lagator, Mato; Igler, Claudia; Moreno, Anaísa B.; Guet, Călin C.; Bollback, Jonathan P.

    2016-01-01

    Changes in gene expression are an important mode of evolution; however, the proximate mechanism of these changes is poorly understood. In particular, little is known about the effects of mutations within cis binding sites for transcription factors, or the nature of epistatic interactions between these mutations. Here, we tested the effects of single and double mutants in two cis binding sites involved in the transcriptional regulation of the Escherichia coli araBAD operon, a component of arabinose metabolism, using a synthetic system. This system decouples transcriptional control from any posttranslational effects on fitness, allowing a precise estimate of the effect of single and double mutations, and hence epistasis, on gene expression. We found that epistatic interactions between mutations in the araBAD cis-regulatory element are common, and that the predominant form of epistasis is negative. The magnitude of the interactions depended on whether the mutations are located in the same or in different operator sites. Importantly, these epistatic interactions were dependent on the presence of arabinose, a native inducer of the araBAD operon in vivo, with some interactions changing in sign (e.g., from negative to positive) in its presence. This study thus reveals that mutations in even relatively simple cis-regulatory elements interact in complex ways such that selection on the level of gene expression in one environment might perturb regulation in the other environment in an unpredictable and uncorrelated manner. PMID:26589997

  19. Epistatic Interactions in the Arabinose Cis-Regulatory Element.

    PubMed

    Lagator, Mato; Igler, Claudia; Moreno, Anaísa B; Guet, Călin C; Bollback, Jonathan P

    2016-03-01

    Changes in gene expression are an important mode of evolution; however, the proximate mechanism of these changes is poorly understood. In particular, little is known about the effects of mutations within cis binding sites for transcription factors, or the nature of epistatic interactions between these mutations. Here, we tested the effects of single and double mutants in two cis binding sites involved in the transcriptional regulation of the Escherichia coli araBAD operon, a component of arabinose metabolism, using a synthetic system. This system decouples transcriptional control from any posttranslational effects on fitness, allowing a precise estimate of the effect of single and double mutations, and hence epistasis, on gene expression. We found that epistatic interactions between mutations in the araBAD cis-regulatory element are common, and that the predominant form of epistasis is negative. The magnitude of the interactions depended on whether the mutations are located in the same or in different operator sites. Importantly, these epistatic interactions were dependent on the presence of arabinose, a native inducer of the araBAD operon in vivo, with some interactions changing in sign (e.g., from negative to positive) in its presence. This study thus reveals that mutations in even relatively simple cis-regulatory elements interact in complex ways such that selection on the level of gene expression in one environment might perturb regulation in the other environment in an unpredictable and uncorrelated manner. PMID:26589997

  20. Reciprocal Regulation of l-Arabinose and d-Xylose Metabolism in Escherichia coli

    PubMed Central

    Koirala, Santosh; Wang, Xiaoyi

    2015-01-01

    ABSTRACT Glucose is known to inhibit the transport and metabolism of many sugars in Escherichia coli. This mechanism leads to its preferential consumption. Far less is known about the preferential utilization of nonglucose sugars in E. coli. Two exceptions are l-arabinose and d-xylose. Previous studies have shown that l-arabinose inhibits d-xylose metabolism in Escherichia coli. This repression results from l-arabinose-bound AraC binding to the promoter of the d-xylose metabolic genes and inhibiting their expression. This mechanism, however, has not been explored in single cells. Both the l-arabinose and d-xylose utilization systems are known to exhibit a bimodal induction response to their cognate sugar, where mixed populations of cells either expressing the metabolic genes or not are observed at intermediate sugar concentrations. This suggests that l-arabinose can only inhibit d-xylose metabolism in l-arabinose-induced cells. To understand how cross talk between these systems affects their response, we investigated E. coli during growth on mixtures of l-arabinose and d-xylose at single-cell resolution. Our results showed that mixed, multimodal populations of l-arabinose- and d-xylose-induced cells occurred at intermediate sugar concentrations. We also found that d-xylose inhibited the expression of the l-arabinose metabolic genes and that this repression was due to XylR. These results demonstrate that a strict hierarchy does not exist between l-arabinose and d-xylose as previously thought. The results may also aid in the design of E. coli strains capable of simultaneous sugar consumption. IMPORTANCE Glucose, d-xylose, and l-arabinose are the most abundant sugars in plant biomass. Developing efficient fermentation processes that convert these sugars into chemicals and fuels will require strains capable of coutilizing these sugars. Glucose has long been known to repress the expression of the l-arabinose and d-xylose metabolic genes in Escherichia coli. Recent

  1. Absence of residual structure in the intrinsically disordered regulatory protein CP12 in its reduced state.

    PubMed

    Launay, Hélène; Barré, Patrick; Puppo, Carine; Manneville, Stéphanie; Gontero, Brigitte; Receveur-Bréchot, Véronique

    2016-08-12

    The redox switch protein CP12 is a key player of the regulation of the Benson-Calvin cycle. Its oxidation state is controlled by the formation/dissociation of two intramolecular disulphide bridges during the day/night cycle. CP12 was known to be globally intrinsically disordered on a large scale in its reduced state, while being partly ordered in the oxidised state. By combining Nuclear Magnetic Resonance and Small Angle X-ray Scattering experiments, we showed that, contrary to secondary structure or disorder predictions, reduced CP12 is fully disordered, with no transient or local residual structure likely to be precursor of the structures identified in the oxidised active state and/or in the bound state with GAPDH or PRK. These results highlight the diversity of the mechanisms of regulation of conditionally disordered redox switches, and question the stability of oxidised CP12 scaffold. PMID:27268235

  2. Hydride vapor phase GaN films with reduced density of residual electrons and deep traps

    SciTech Connect

    Polyakov, A. Y.; Smirnov, N. B.; Govorkov, A. V.; Yugova, T. G.; Cox, H.; Helava, H.; Makarov, Yu.; Usikov, A. S.

    2014-05-14

    Electrical properties and deep electron and hole traps spectra are compared for undoped n-GaN films grown by hydride vapor phase epitaxy (HVPE) in the regular process (standard HVPE samples) and in HVPE process optimized for decreasing the concentration of residual donor impurities (improved HVPE samples). It is shown that the residual donor density can be reduced by optimization from ∼10{sup 17} cm{sup −3} to (2–5) × 10{sup 14} cm{sup −3}. The density of deep hole traps and deep electron traps decreases with decreased donor density, so that the concentration of deep hole traps in the improved samples is reduced to ∼5 × 10{sup 13} cm{sup −3} versus 2.9 × 10{sup 16} cm{sup −3} in the standard samples, with a similar decrease in the electron traps concentration.

  3. Reduced parenteral nutrition requirements following anastomosis of a short residual colonic segment to a short jejunum.

    PubMed

    Smith, Katherine H; Saunders, John A; Nugent, Karen P; Jackson, Alan A; Stroud, Michael A

    2011-11-01

    A 22-year-old man suffered an acute small bowel infarct leading to extensive bowel resection, resulting in only 20 cm of jejunum to a jejunostomy, although he also had 50 cm of residual colon with a mucous fistula. The patient was out on long-term home parenteral nutrition (PN) but endured high stomal losses of 5-6 L per day and, despite all conventional measures, required 6.1 L of fluid (including PN) and 555 mmol sodium per day. Although body mass index was maintained, he suffered debilitating malaise and recurrent episodes of catheter-related sepsis and also developed persistently abnormal liver function tests. He was considered a potential intestinal transplant patient, but before taking that step, he opted for reanastomosis of his residual colon to his jejunum, ending in a colostomy. At surgery, only 30 cm of additional bowel lengthening could be achieved, but despite this, the patient's stomal losses reduced to 2.5 L per day, intravenous fluid requirements reduced to 4.1 L per day, and liver function normalized. The patient also gained 7.5 kg despite no change in PN caloric prescription, and his quality of life was dramatically enhanced. The case illustrates that even a small length of colon can grant significant improvements, probably via improvements in small bowel transit and adaptive changes, better sodium and water resorption with decreased hyperaldosteronism, and enhanced energy and nitrogen recovery. Reanastomosis of defunctioned colon should therefore always be considered a management option in short bowel syndrome. PMID:22042049

  4. Galacturonic Acid Inhibits the Growth of Saccharomyces cerevisiae on Galactose, Xylose, and Arabinose

    PubMed Central

    Huisjes, Eline H.; de Hulster, Erik; van Dam, Jan C.; Pronk, Jack T.

    2012-01-01

    The efficient fermentation of mixed substrates is essential for the microbial conversion of second-generation feedstocks, including pectin-rich waste streams such as citrus peel and sugar beet pulp. Galacturonic acid is a major constituent of hydrolysates of these pectin-rich materials. The yeast Saccharomyces cerevisiae, the main producer of bioethanol, cannot use this sugar acid. The impact of galacturonic acid on alcoholic fermentation by S. cerevisiae was investigated with anaerobic batch cultures grown on mixtures of glucose and galactose at various galacturonic acid concentrations and on a mixture of glucose, xylose, and arabinose. In cultures grown at pH 5.0, which is well above the pKa value of galacturonic acid (3.51), the addition of 10 g · liter−1 galacturonic acid did not affect galactose fermentation kinetics and growth. In cultures grown at pH 3.5, the addition of 10 g · liter−1 galacturonic acid did not significantly affect glucose consumption. However, at this lower pH, galacturonic acid completely inhibited growth on galactose and reduced galactose consumption rates by 87%. Additionally, it was shown that galacturonic acid strongly inhibits the fermentation of xylose and arabinose by the engineered pentose-fermenting S. cerevisiae strain IMS0010. The data indicate that inhibition occurs when nondissociated galacturonic acid is present extracellularly and corroborate the hypothesis that a combination of a decreased substrate uptake rate due to competitive inhibition on Gal2p, an increased energy requirement to maintain cellular homeostasis, and/or an accumulation of galacturonic acid 1-phosphate contributes to the inhibition. The role of galacturonic acid as an inhibitor of sugar fermentation should be considered in the design of yeast fermentation processes based on pectin-rich feedstocks. PMID:22582063

  5. Role of plant residues in determining temporal patterns of the activity, size, and structure of nitrate reducer communities in soil.

    PubMed

    Chèneby, D; Bru, D; Pascault, N; Maron, P A; Ranjard, L; Philippot, L

    2010-11-01

    The incorporation of plant residues into soil not only represents an opportunity to limit soil organic matter depletion resulting from cultivation but also provides a valuable source of nutrients such as nitrogen. However, the consequences of plant residue addition on soil microbial communities involved in biochemical cycles other than the carbon cycle are poorly understood. In this study, we investigated the responses of one N-cycling microbial community, the nitrate reducers, to wheat, rape, and alfalfa residues for 11 months after incorporation into soil in a field experiment. A 20- to 27-fold increase in potential nitrate reduction activity was observed for residue-amended plots compared to the nonamended plots during the first week. This stimulating effect of residues on the activity of the nitrate-reducing community rapidly decreased but remained significant over 11 months. During this period, our results suggest that the potential nitrate reduction activity was regulated by both carbon availability and temperature. The presence of residues also had a significant effect on the abundance of nitrate reducers estimated by quantitative PCR of the narG and napA genes, encoding the membrane-bound and periplasmic nitrate reductases, respectively. In contrast, the incorporation of the plant residues into soil had little impact on the structure of the narG and napA nitrate-reducing community determined by PCR-restriction fragment length polymorphism (RFLP) fingerprinting. Overall, our results revealed that the addition of plant residues can lead to important long-term changes in the activity and size of a microbial community involved in N cycling but with limited effects of the type of plant residue itself. PMID:20833788

  6. Biosynthesis of d-arabinose in Mycobacterium smegmatis: specific labeling from d-glucose.

    PubMed

    Klutts, J Stacey; Hatanaka, Kenichi; Pan, Y T; Elbein, Alan D

    2002-02-15

    d-Arabinose is a major sugar in the cell wall polysaccharides of Mycobacterium tuberculosis and other mycobacterial species. The reactions involved in the biosynthesis and activation of d-arabinose represent excellent potential sites for drug intervention since d-arabinose is not found in mammalian cells, and the cell wall arabinomannan and/or arabinogalactan appear to be essential for cell survival. Since the pathway involved in conversion of d-glucose to d-arabinose is unknown, we incubated cells of Mycobacterium smegmatis individually with [1-(14)C]glucose, [3,4-(14)C]glucose, and [6-(14)C]glucose and compared the specific activities of the cell wall-bound arabinose. Although the specific activity of the arabinose was about 25% lower with [6-(14)C]glucose than with other labels, there did not appear to be selective loss of either carbon 1 or carbon 6, suggesting that arabinose was not formed by loss of carbon 1 of glucose via the oxidative step of the pentose phosphate pathway, or by loss of carbon 6 in the uronic acid pathway. Similar labeling patterns were observed with ribose isolated from the nucleic acid fraction. Since these results suggested an unusual pathway of pentose formation, labeling studies were also done with [1-(13)C]glucose, [2-(13)C]glucose, and [6-(13)C]glucose and the cell wall arabinose was examined by NMR analysis. This method allows one to determine the relative (13)C content in each carbon of the arabinose. The labeling patterns suggested that the most likely pathway was condensation of carbons 1 and 2 of fructose 6-phosphate produced by the transaldolase reaction with carbons 4, 5, and 6 (i.e., glyceraldehyde 3-phosphate) formed by fructose-1,6 bisphosphate aldolase. Cell-free enzyme extracts of M. smegmatis were incubated with ribose 5-phosphate, xylulose 5-phosphate, and d-arabinose 5-phosphate under a variety of experimental conditions. Although the ribose 5-phosphate and xylulose 5-phosphate were converted to other pentoses and

  7. l-Arabinose Binding Protein from Escherichia coli B/r

    PubMed Central

    Hogg, R. W.; Englesberg, E.

    1969-01-01

    A protein which is capable of binding l-arabinose-1-14C has been isolated from l-arabinose-induced cultures of Escherichia coli B/r. Analysis for this l-arabinose-binding protein (ABP) in a number of l-arabinose-negative mutants suggests that the ABP is not coded for by any of the known genetic units of the l-arabinose complex yet is under the control of the regulator gene araC. The ABP has been purified and found to bind l-arabinose, d-fucose, d-xylose, and l-ribulose with decreasing affinities. The Km for l-arabinose is 5.7 × 10−6m. The molecular weight, as determined by equilibrium centrifugation, was found to be 32,000. The protein was observed to have many features that liken it to other recently isolated binding proteins that have been implicated in the active transport of small molecules. Images PMID:4899002

  8. Engineering of an L-arabinose metabolic pathway in Rhodococcus jostii RHA1 for biofuel production.

    PubMed

    Xiong, Xiaochao; Wang, Xi; Chen, Shulin

    2016-07-01

    The oleaginous bacterium, Rhodococcus jostii RHA1 has attracted considerable attention due to its capability to accumulate significant levels of triacylglycerol as renewable hydrocarbon. To enable the strain to utilize arabinose derived from lignocellulosic biomass, the metabolic pathway of L-arabinose utilization was introduced into R. jostii RHA1 by heterogenous expression of the operon, araBAD from Escherichia coli. The results showed that recombinant bearing araBAD could grow on L-arabinose as the sole carbon source, and additional expression of araFGH encoding the arabinose transporter from E. coli could improve the cell biomass yield from high contents of arabinose. We further increased the content of lipid produced from arabinose in the recombinants from 47.9 to 56.8 % of the cell dry weight (CDW) by overexpression of a gene, atf1 encoding a diglyceride acyltransferase from R. opacus PD630. This work demonstrated the feasibility of producing lipid from arabinose by genetic modification of the rhodococci strain. PMID:27143134

  9. Utilization and Transport of L-Arabinose by Non-Saccharomyces Yeasts

    SciTech Connect

    Knoshaug, E. P.; Franden, M. A.; Stambuk, B. U.; Zhang, M.; Singh, A.

    2009-01-01

    L-Arabinose is one of the sugars found in hemicellulose, a major component of plant cell walls. The ability to convert L-arabinose to ethanol would improve the economics of biomass to ethanol fermentations. One of the limitations for L-arabinose fermentation in the current engineered Saccharomyces cerevisiae strains is poor transport of the sugar. To better understand L-arabinose transport and use in yeasts and to identify a source for efficient L-arabinose transporters, 165 non-Saccharomyces yeast strains were studied. These yeast strains were arranged into six groups based on the minimum time required to utilize 20 g/L of L-arabinose. Initial transport rates of L-arabinose were determined for several species and a more comprehensive transport study was done in four selected species. Detailed transport kinetics in Arxula adeninivorans suggested both low and high affinity components while Debaryomyces hansenii var. fabryii, Kluyveromyces marxianus and Pichia guilliermondii possessed a single component, high affinity active transport systems.

  10. Targeting bacterial membranes: NMR spectroscopy characterization of substrate recognition and binding requirements of D-arabinose-5-phosphate isomerase.

    PubMed

    Airoldi, Cristina; Sommaruga, Silvia; Merlo, Silvia; Sperandeo, Paola; Cipolla, Laura; Polissi, Alessandra; Nicotra, Francesco

    2010-02-01

    Lipopolysaccharide (LPS) is an essential component of the outer membrane of gram-negative bacteria and consists of three elements: lipid A, the core oligosaccharide, and the O-antigen. The inner-core region is highly conserved and contains at least one residue of 3-deoxy-D-manno-octulosonate (Kdo). Arabinose-5-phosphate isomerase (API) is an aldo-keto isomerase catalyzing the reversible isomerization of D-ribulose-5-phosphate (Ru5P) to D-arabinose-5-phosphate (A5P), the first step of Kdo biosynthesis. By exploiting saturation transfer difference (STD) NMR spectroscopy, the structural requirements necessary for API substrate recognition and binding were identified, with the aim of designing new API inhibitors. In addition, simple experimental conditions for the STD experiments to perform a fast, robust, and efficient screening of small libraries of potential API inhibitors, allowing the identification of new potential leads, were set up. Due to the essential role of API enzymes in LPS biosynthesis and gram-negative bacteria survival, by exploiting these data, a new generation of potent antibacterial drugs could be developed. PMID:20039350

  11. L-arabinose/D-galactose 1-dehydrogenase of Rhizobium leguminosarum bv. trifolii characterised and applied for bioconversion of L-arabinose to L-arabonate with Saccharomyces cerevisiae.

    PubMed

    Aro-Kärkkäinen, Niina; Toivari, Mervi; Maaheimo, Hannu; Ylilauri, Mikko; Pentikäinen, Olli T; Andberg, Martina; Oja, Merja; Penttilä, Merja; Wiebe, Marilyn G; Ruohonen, Laura; Koivula, Anu

    2014-12-01

    Four potential dehydrogenases identified through literature and bioinformatic searches were tested for L-arabonate production from L-arabinose in the yeast Saccharomyces cerevisiae. The most efficient enzyme, annotated as a D-galactose 1-dehydrogenase from the pea root nodule bacterium Rhizobium leguminosarum bv. trifolii, was purified from S. cerevisiae as a homodimeric protein and characterised. We named the enzyme as a L-arabinose/D-galactose 1-dehydrogenase (EC 1.1.1.-), Rl AraDH. It belongs to the Gfo/Idh/MocA protein family, prefers NADP(+) but uses also NAD(+) as a cofactor, and showed highest catalytic efficiency (k cat/K m) towards L-arabinose, D-galactose and D-fucose. Based on nuclear magnetic resonance (NMR) and modelling studies, the enzyme prefers the α-pyranose form of L-arabinose, and the stable oxidation product detected is L-arabino-1,4-lactone which can, however, open slowly at neutral pH to a linear L-arabonate form. The pH optimum for the enzyme was pH 9, but use of a yeast-in-vivo-like buffer at pH 6.8 indicated that good catalytic efficiency could still be expected in vivo. Expression of the Rl AraDH dehydrogenase in S. cerevisiae, together with the galactose permease Gal2 for L-arabinose uptake, resulted in production of 18 g of L-arabonate per litre, at a rate of 248 mg of L-arabonate per litre per hour, with 86 % of the provided L-arabinose converted to L-arabonate. Expression of a lactonase-encoding gene from Caulobacter crescentus was not necessary for L-arabonate production in yeast. PMID:25236800

  12. INDUCTION AND REPRESSION OF l-ARABINOSE ISOMERASE IN PEDIOCOCCUS PENTOSACEUS1

    PubMed Central

    Dobrogosz, Walter J.; DeMoss, Ralph D.

    1963-01-01

    Dobrogosz, Walter J. (University of Illinois, Urbana) and Ralph D. DeMoss. Induction and repression of l-arabinose isomerase in Pediococcus pentosaceus. J. Bacteriol. 85:1350–1355. 1963.—The inducible l-arabinose isomerase of Pediococcus pentosaceus can be rapidly and conveniently measured in whole-cell preparations by use of a standard colorimetric procedure originally developed for studies with cell-free enzyme preparations. The enzyme is measured by its ability to catalyze the isomerization of l-arabinose to l-ribulose. Whole cells suspended in a suitable buffer and pretreated with toluene were shown to exhibit this isomerase activity at a level comparable with that observed in cell-free enzyme preparations. Conditions for optimal induction of l-arabinose isomerase are described. In addition, it was determined that the formation of this enzyme is subject to repression by glucose, i.e., via catabolite repression. PMID:14047229

  13. Bioprospecting and evolving alternative xylose and arabinose pathway enzymes for use in Saccharomyces cerevisiae.

    PubMed

    Lee, Sun-Mi; Jellison, Taylor; Alper, Hal S

    2016-03-01

    Bioprospecting is an effective way to find novel enzymes from strains with desirable phenotypes. Such bioprospecting has enabled organisms such as Saccharomyces cerevisiae to utilize nonnative pentose sugars. Yet, the efficiency of this pentose catabolism (especially for the case of arabinose) remains suboptimal. Thus, further pathway optimization or identification of novel, optimal pathways is needed. Previously, we identified a novel set of xylan catabolic pathway enzymes from a superior pentose-utilizing strain of Ustilago bevomyces. These enzymes were used to successfully engineer a xylan-utilizing S. cerevisiae through a blended approach of bioprospecting and evolutionary engineering. Here, we expanded this approach to xylose and arabinose catabolic pathway engineering and demonstrated that bioprospected xylose and arabinose catabolic pathways from U. bevomyces offer alternative choices for enabling efficient pentose catabolism in S. cerevisiae. By introducing a novel set of xylose catabolic genes from U. bevomyces, growth rates were improved up to 85 % over a set of traditional Scheffersomyces stipitis pathway genes. In addition, we suggested an alternative arabinose catabolic pathway which, after directed evolution and pathway engineering, enabled S. cerevisiae to grow on arabinose as a sole carbon source in minimal medium with growth rates upwards of 0.05 h(-1). This pathway represents the most efficient growth of yeast on pure arabinose minimal medium. These pathways provide great starting points for further strain development and demonstrate the utility of bioprospecting from U. bevomyces. PMID:26671616

  14. Biochemical preparation of L-ribose and L-arabinose from ribitol: a new approach.

    PubMed

    Ahmed, Z; Shimonishi, T; Bhuiyan, S H; Utamura, M; Takada, G; Izumori, K

    1999-01-01

    L-ribose and L-arabinose were prepared biochemically from ribitol via a two-step reaction, by which the complete oxidation of ribitol to L-ribulose (approximately 98%) was achieved by the reaction of washed cells of Acetobacter aceti IFO 3281. The produced L-ribulose was then used as a substrate for the production of L-ribose and L-arabinose. The isomerization of L-ribulose to L-ribose and L-arabinose was carried out using L-ribose isomerase (L-RI) of Acinetobacter sp. strain DL-28 and L-arabinose isomerase (L-AI) of Mycobacterium smegmatis, respectively. At equilibrium, the ratio of L-ribose: L-ribulose was 70:30 and that of L-arabinose: L-ribulose was 90: 10. After a simple purification treatment, both pentoses could be crystallized without the use of column chromatography. The crystals were confirmed as L-ribose and L-arabinose by High-performance liquid chromatography (HPLC), Infrared (IR), Nuclear magnetic resonance (NMR) and optical rotation measurements. PMID:16232643

  15. Biofuels from crop residue can reduce soil carbon and increase CO2 emissions

    NASA Astrophysics Data System (ADS)

    Liska, Adam J.; Yang, Haishun; Milner, Maribeth; Goddard, Steve; Blanco-Canqui, Humberto; Pelton, Matthew P.; Fang, Xiao X.; Zhu, Haitao; Suyker, Andrew E.

    2014-05-01

    Removal of corn residue for biofuels can decrease soil organic carbon (SOC; refs , ) and increase CO2 emissions because residue C in biofuels is oxidized to CO2 at a faster rate than when added to soil. Net CO2 emissions from residue removal are not adequately characterized in biofuel life cycle assessment (LCA; refs , , ). Here we used a model to estimate CO2 emissions from corn residue removal across the US Corn Belt at 580 million geospatial cells. To test the SOC model, we compared estimated daily CO2 emissions from corn residue and soil with CO2 emissions measured using eddy covariance, with 12% average error over nine years. The model estimated residue removal of 6 Mg per ha-1 yr-1 over five to ten years could decrease regional net SOC by an average of 0.47-0.66 Mg C ha-1 yr-1. These emissions add an average of 50-70 g CO2 per megajoule of biofuel (range 30-90) and are insensitive to the fraction of residue removed. Unless lost C is replaced, life cycle emissions will probably exceed the US legislative mandate of 60% reduction in greenhouse gas (GHG) emissions compared with gasoline.

  16. D-arabinose metabolism in Escherichia coli B: induction and cotransductional mapping of the L-fucose-D-arabinose pathway enzymes.

    PubMed

    Elsinghorst, E A; Mortlock, R P

    1988-12-01

    D-Arabinose is degraded by Escherichia coli B via some of the L-fucose pathway enzymes and a D-ribulokinase which is distinct from the L-fuculokinase of the L-fucose pathway. We found that L-fucose and D-arabinose acted as the apparent inducers of the enzymes needed for their degradation. These enzymes, including D-ribulokinase, appeared to be coordinately regulated, and mutants which constitutively synthesized the L-fucose enzymes also constitutively synthesized D-ribulokinase. In contrast to D-arabinose-positive mutants of E. coli K-12, in which L-fuculose-1-phosphate and D-ribulose-1-phosphate act as inducers of the L-fucose pathway, we found that these intermediates did not act as inducers in E. coli B. To further characterize the E. coli B system, some of the L-fucose-D-arabinose genes were mapped by using bacteriophage P1 transduction. A transposon Tn10 insertion near the E. coli B L-fucose regulon was used in two- and three-factor reciprocal crosses. The gene encoding D-ribulokinase, designated darK, was found to map within the L-fucose regulon, and the partial gene order was found to be Tn10-fucA-darK-fucI-fucK-thyA. PMID:3056899

  17. Consumption of residue containing cucurbitacin feeding stimulant and reduced rates of carbaryl insecticide by western corn rootworm (Coleoptera: Chrysomelidae).

    PubMed

    Behle, R W

    2001-12-01

    Application of insecticide at a reduced rate with a cucurbitacin-based feeding stimulant is a viable alternative to a broadcast insecticide application for control of adult western corn rootworms, Diabrotica virgifera virgifera, LeConte. Because of the small amount of material applied, it is conceivable that a high density of beetles could consume all of the spray residue before economic control is achieved. A laboratory experiment was conducted to determine the amount of cucurbitacin-based spray residue consumed by beetles. Dried residue of four treatments were exposed to three groups of 10 rootworm beetles for 1 h each. Treatments consisted of a cucurbitacin-based adjuvant (Cidetrak CRW, Trécé, Salinas, CA) with carbaryl insecticide (Sevin XLR Plus, Rhone Poulenc, Research Triangle Park, NC) mixed at 0, 0.12, 1.2, and 12 g (AI)/liter. For the treatment with cucurbitacin adjuvant only (no insecticide), beetles consumed 0.029 mg beetle(-1) h(-1) of exposure. Approximately 54% of the beetles were recorded as feeding at any given time during the 60-min feeding period. However, when the spray residue contained carbaryl, no weight loss of treatment residue was measured, though the beetles were observed to feed from the residue during the first few minutes of exposure. When residue included insecticide, beetles quickly ceased feeding (within 20 min), and toxicity behavior was observed 30 min after initial exposure for up to 75% of the beetles, which were classified as moribund (unable to stand upright). Beetle mortality was recorded 24 h after exposure and demonstrated that male beetles (53% dead for three insecticide treatments) were more susceptible to carbaryl toxicity than female beetles (28% dead for three insecticide treatments). Regression analysis showed a significant positive relationship between mortality of female beetles and ovarian development. Based on the measurements of this experiment, it is unlikely that realistic beetle densities would consume

  18. [Effect of reduced N application on soil N residue and N loss in maize-soybean relay strip intercropping system].

    PubMed

    Liu, Xiao-Ming; Yong, Tai-Wen; Liu, Wen-Yu; Su, Ben-Ying; Song, Chun; Yang, Feng; Wang, Xiao-Chun; Yang, Wen-Yu

    2014-08-01

    A field experiment was conducted in 2012, including three planting pattern (maize-soybean relay strip intercropping, mono-cultured maize and soybean) and three nitrogen application level [0 kg N x hm(-2), 180 kg N x hm(-2) (reduced N) and 240 kg N x hm(-2) (normal N)]. Fields were assigned to different treatments in a randomized block design with three replicates. The objective of this work was to analyze the effects of planting patterns and nitrogen application rates on plant N uptake, soil N residue and N loss. After fertilization applications, NH4(+)-N and NO3(-)-N levels increased in the soil of intercropped maize but decreased in the soil of intercropped soybean. Compared with mono-crops, the soil N residue and loss of intercropped soybean were reduced, while those of intercropped maize were increased and decreased, respectively. With the reduced rate of N application, N residue rate, N loss rate and ammonia volatilization loss rate of the maize-soybean intercropping relay strip system were decreased by 17.7%, 21.5% and 0.4% compared to mono-cultured maize, but increased by 2.0%, 19.8% and 0.1% compared to mono-cultured soybean, respectively. Likewise, the reduced N application resulted in reductions in N residue, N loss, and the N loss via ammonia volatilization in the maize-soybean relay strip intercropping system compared with the conventional rate of N application adopted by local farmers, and the N residue rate, N loss rate and ammonia volatilization loss rate reduced by 12.0%, 15.4% and 1.2%, respectively. PMID:25509077

  19. Molecular cloning of the Escherichia coli B L-fucose-D-arabinose gene cluster.

    PubMed Central

    Elsinghorst, E A; Mortlock, R P

    1994-01-01

    To metabolize the uncommon pentose D-arabinose, enteric bacteria often recruit the enzymes of the L-fucose pathway by a regulatory mutation. However, Escherichia coli B can grow on D-arabinose without the requirement of a mutation, using some of the L-fucose enzymes and a D-ribulokinase that is distinct from the L-fuculokinase of the L-fucose pathway. To study this naturally occurring D-arabinose pathway, we cloned and partially characterized the E. coli B L-fucose-D-arabinose gene cluster and compared it with the L-fucose gene cluster of E. coli K-12. The order of the fucA, -P, -I, and -K genes was the same in the two E. coli strains. However, the E. coli B gene cluster contained a 5.2-kb segment located between the fucA and fucP genes that was not present in E. coli K-12. This segment carried the darK gene, which encodes the D-ribulokinase needed for growth on D-arabinose by E. coli B. The darK gene was not homologous with any of the L-fucose genes or with chromosomal DNA from other D-arabinose-utilizing bacteria. D-Ribulokinase and L-fuculokinase were purified to apparent homogeneity and partially characterized. The molecular weights, substrate specificities, and kinetic parameters of these two enzymes were very dissimilar, which together with DNA hybridization analysis, suggested that these enzymes are not related. D-Arabinose metabolism by E. coli B appears to be the result of acquisitive evolution, but the source of the darK gene has not been determined. Images PMID:7961494

  20. Hydrophobic carboxy-terminal residues dramatically reduce protein levels in the haloarchaeon Haloferax volcanii

    PubMed Central

    Reuter, Christopher J.; Uthandi, Sivakumar; Puentes, Jose A.; Maupin-Furlow, Julie A.

    2010-01-01

    Proteolysis is important not only to cell physiology but also to the successful development of biocatalysts. While a wide-variety of signals are known to trigger protein degradation in bacteria and eukaryotes, these mechanisms are poorly understood in archaea, known for their ability to withstand harsh conditions. Here we present a systematic study in which single C-terminal amino acid residues were added to a reporter protein and shown to influence its levels in an archaeal cell. All 20 amino acid residues were examined for their impact on protein levels, using the reporter protein soluble modified red-shifted GFP (smRS-GFP) expressed in the haloarchaeon Haloferax volcanii as a model system. Addition of hydrophobic residues, including Leu, Cys, Met, Phe, Ala, Tyr, Ile and Val, gave the most pronounced reduction in smRS-GFP levels compared with the addition of either neutral or charged hydrophilic residues. In contrast to the altered protein levels, the C-terminal alterations had no influence on smRS-GFP-specific transcript levels, thus revealing that the effect is post-transcriptional. PMID:19850616

  1. USING REDUCING AGENTS TO ELIMINATE CHLORINE DIOXIDE AND CHLORITE ION RESIDUALS IN DRINKING WATER

    EPA Science Inventory

    In an effort to determine the viability of various disinfection alternatives, the Evansville, Ind. Water and Sewer Utility is engaged in a pilot-plant investigation to compare chlorine dioxide and ozone pretreatment. As a result of increased speculation that the total residual c...

  2. Production of Acetoin through Simultaneous Utilization of Glucose, Xylose, and Arabinose by Engineered Bacillus subtilis

    PubMed Central

    Fu, Jing; Li, Ning; Wang, Zhiwen; Tang, Ya-jie; Chen, Tao

    2016-01-01

    Glucose, xylose and arabinose are the three most abundant monosaccharide found in lignocellulosic biomass. Effectively and simultaneously utilization of these sugars by microorganisms for production of the biofuels and bio-chemicals is essential toward directly fermentation of the lignocellulosic biomass. In our previous study, the recombinant Bacillus subtilis 168ARSRCPΔacoAΔbdhA strain was already shown to efficiently utilize xylose for production of acetoin, with a yield of 0.36 g/g xylose. In the current study, the Bacillus subtilis168ARSRCPΔacoAΔbdhA strain was further engineered to produce acetoin from a glucose, xylose, and arabinose mixtures. To accomplish this, the endogenous xylose transport protein AraE, the exogenous xylose isomerase gene xylA and the xylulokinase gene xylB from E. coli were co-overexpressed in the Bacillus subtilis 168ARSRCPΔacoAΔbdhA strain, which enabled the resulting strain, denoted ZB02, to simultaneously utilize glucose and xylose. Unexpectedly, the ZB02 strain could simultaneously utilize glucose and arabinose also. Further results indicated that the transcriptional inhibition of the arabinose transport protein gene araE was the main limiting factor for arabinose utilization in the presence of glucose. Additionally, the arabinose operon in B. subtilis could be activated by the addition of arabinose, even in the presence of glucose. Through fed-batch fermentation, strain ZB02 could simultaneously utilize glucose, xylose, and arabinose, with an average sugar consumption rate of 3.00 g/l/h and an average production of 62.2 g/l acetoin at a rate of 0.864 g/l/h. Finally, the strain produced 11.2 g/l acetoin from lignocellulosic hydrolysate (containing 20.6g/l glucose, 12.1 g/l xylose and 0.45 g/l arabinose) in flask cultivation, with an acetoin yield of 0.34 g/g total sugar. The result demonstrates that this strain has good potential for the utilization of lignocellulosic hydrolysate for production of acetoin. PMID:27467131

  3. Production of Acetoin through Simultaneous Utilization of Glucose, Xylose, and Arabinose by Engineered Bacillus subtilis.

    PubMed

    Zhang, Bo; Li, Xin-Li; Fu, Jing; Li, Ning; Wang, Zhiwen; Tang, Ya-Jie; Chen, Tao

    2016-01-01

    Glucose, xylose and arabinose are the three most abundant monosaccharide found in lignocellulosic biomass. Effectively and simultaneously utilization of these sugars by microorganisms for production of the biofuels and bio-chemicals is essential toward directly fermentation of the lignocellulosic biomass. In our previous study, the recombinant Bacillus subtilis 168ARSRCPΔacoAΔbdhA strain was already shown to efficiently utilize xylose for production of acetoin, with a yield of 0.36 g/g xylose. In the current study, the Bacillus subtilis168ARSRCPΔacoAΔbdhA strain was further engineered to produce acetoin from a glucose, xylose, and arabinose mixtures. To accomplish this, the endogenous xylose transport protein AraE, the exogenous xylose isomerase gene xylA and the xylulokinase gene xylB from E. coli were co-overexpressed in the Bacillus subtilis 168ARSRCPΔacoAΔbdhA strain, which enabled the resulting strain, denoted ZB02, to simultaneously utilize glucose and xylose. Unexpectedly, the ZB02 strain could simultaneously utilize glucose and arabinose also. Further results indicated that the transcriptional inhibition of the arabinose transport protein gene araE was the main limiting factor for arabinose utilization in the presence of glucose. Additionally, the arabinose operon in B. subtilis could be activated by the addition of arabinose, even in the presence of glucose. Through fed-batch fermentation, strain ZB02 could simultaneously utilize glucose, xylose, and arabinose, with an average sugar consumption rate of 3.00 g/l/h and an average production of 62.2 g/l acetoin at a rate of 0.864 g/l/h. Finally, the strain produced 11.2 g/l acetoin from lignocellulosic hydrolysate (containing 20.6g/l glucose, 12.1 g/l xylose and 0.45 g/l arabinose) in flask cultivation, with an acetoin yield of 0.34 g/g total sugar. The result demonstrates that this strain has good potential for the utilization of lignocellulosic hydrolysate for production of acetoin. PMID:27467131

  4. High-level hemicellulosic arabinose predominately affects lignocellulose crystallinity for genetically enhancing both plant lodging resistance and biomass enzymatic digestibility in rice mutants.

    PubMed

    Li, Fengcheng; Zhang, Mingliang; Guo, Kai; Hu, Zhen; Zhang, Ran; Feng, Yongqing; Yi, Xiaoyan; Zou, Weihua; Wang, Lingqiang; Wu, Changyin; Tian, Jinshan; Lu, Tiegang; Xie, Guosheng; Peng, Liangcai

    2015-05-01

    Rice is a major food crop with enormous biomass residue for biofuels. As plant cell wall recalcitrance basically decides a costly biomass process, genetic modification of plant cell walls has been regarded as a promising solution. However, due to structural complexity and functional diversity of plant cell walls, it becomes essential to identify the key factors of cell wall modifications that could not much alter plant growth, but cause an enhancement in biomass enzymatic digestibility. To address this issue, we performed systems biology analyses of a total of 36 distinct cell wall mutants of rice. As a result, cellulose crystallinity (CrI) was examined to be the key factor that negatively determines either the biomass enzymatic saccharification upon various chemical pretreatments or the plant lodging resistance, an integrated agronomic trait in plant growth and grain production. Notably, hemicellulosic arabinose (Ara) was detected to be the major factor that negatively affects cellulose CrI probably through its interlinking with β-1,4-glucans. In addition, lignin and G monomer also exhibited the positive impact on biomass digestion and lodging resistance. Further characterization of two elite mutants, Osfc17 and Osfc30, showing normal plant growth and high biomass enzymatic digestion in situ and in vitro, revealed the multiple GH9B candidate genes for reducing cellulose CrI and XAT genes for increasing hemicellulosic Ara level. Hence, the results have suggested the potential cell wall modifications for enhancing both biomass enzymatic digestibility and plant lodging resistance by synchronically overexpressing GH9B and XAT genes in rice. PMID:25418842

  5. Efficiency of light-emitting diode and halogen units in reducing residual monomers

    PubMed Central

    de Assis Ribeiro Carvalho, Felipe; Almeida, Rhita C.; Almeida, Marco Antonio; Cevidanes, Lucia H. S.; Leite, Marcia C. Amorim M.

    2011-01-01

    Introduction In this in-vitro study, we aimed to compare the residual monomers in composites beneath brackets bonded to enamel, using a light-emitting diode (LED) or a halogen unit, and to compare the residual monomers in the central to the peripheral areas of the composite. Methods Twenty bovine teeth preserved in 0.1% thymol were used in this study. Ten teeth were used to standardize the thickness of the composite film, since different thicknesses would cause different absorbance of light. Brackets were bonded to 10 bovine incisors, with the halogen light (n = 5) and the LED (n = 5). The brackets were debonded, and the remaining composite on the enamel surface was sectioned in 2 regions: peripheral (0.8 mm) and central, resulting in 2 subgroups per group: central halogen (n = 5), peripheral halogen (n = 5), central LED (n = 5), and peripheral LED (n = 5). The spectrometric analysis in the infrared region was used to measure the free monomers with the attenuated total reflectance method. Results Normal distribution was tested by using the Kolmogorov-Smirnov test. Data were compared by 2-way analysis of variance (ANOVA) at P <0.05. The LED group showed fewer residual monomers than did the halogen group (P = 0.014). No differences were found among the regions (P = 0.354), and there were no interactions between light type and region (P = 0.368). Conclusions LED leaves less residual monomer than does the halogen light, even with half of the irradiation time; there were no differences between the central and peripheral regions, and no interaction between light type and region. PMID:21055603

  6. 1H MRS detection of glycine residue of reduced glutathione in vivo

    NASA Astrophysics Data System (ADS)

    Kaiser, Lana G.; Marjańska, Małgorzata; Matson, Gerald B.; Iltis, Isabelle; Bush, Seth D.; Soher, Brian J.; Mueller, Susanne; Young, Karl

    2010-02-01

    Glutathione (GSH) is a powerful antioxidant found inside different kinds of cells, including those of the central nervous system. Detection of GSH in the human brain using 1H MR spectroscopy is hindered by low concentration and spectral overlap with other metabolites. Previous MRS methods focused mainly on the detection of the cysteine residue (GSH-Cys) via editing schemes. This study focuses on the detection of the glycine residue (GSH-Gly), which is overlapped by glutamate and glutamine (Glx) under physiological pH and temperature. The first goal of the study was to obtain the spectral parameters for characterization of the GSH-Gly signal under physiological conditions. The second goal was to investigate a new method of separating GSH-Gly from Glx in vivo. The characterization of the signal was carried out by utilization of numerical simulations as well as experiments over a wide range of magnetic fields (4.0-14 T). The proposed separation scheme utilizes J-difference editing to quantify the Glx contribution to separate it from the GSH-Gly signal. The presented method retains 100% of the GSH-Gly signal. The overall increase in signal to noise ratio of the targeted resonance is calculated to yield a significant SNR improvement compared to previously used methods that target GSH-Cys residue. This allows shorter acquisition times for in vivo human clinical studies.

  7. Directed evolution of AraC for improved compatibility of arabinose- and lactose-inducible promoters.

    PubMed

    Lee, Sung Kuk; Chou, Howard H; Pfleger, Brian F; Newman, Jack D; Yoshikuni, Yasuo; Keasling, Jay D

    2007-09-01

    Synthetic biological systems often require multiple, independently inducible promoters in order to control the expression levels of several genes; however, cross talk between the promoters limits this ability. Here, we demonstrate the directed evolution of AraC to construct an arabinose-inducible (P(BAD)) system that is more compatible with IPTG (isopropyl-beta-D-1-thiogalactopyranoside) induction of a lactose-inducible (P(lac)) system. The constructed system is 10 times more sensitive to arabinose and tolerates IPTG significantly better than the wild type. Detailed studies indicate that the AraC dimerization domain and C terminus are important for the increased sensitivity of AraC to arabinose. PMID:17644634

  8. 13C metabolic flux analysis in Clostridium acetobutylicum during growth on L-arabinose

    NASA Astrophysics Data System (ADS)

    Hurley, Margaret; Sund, Christian; Liu, Sanchao; Germane, Katherine; Servinsky, Matthew; Gerlach, Elliot

    2015-03-01

    Clostridium acetobutylicum's metabolic pathways have been studied for decades due to its metabolic diversity and industrial value, yet many details of its metabolism are continuing to emerge. To elucidate the role of xylulose-5-P/fructose-6-P phosphoketolase (XFP), and the recently discovered Pentose Phosphate Pathway (PKP) in C. acetobutylicum, experimental and computational metabolic isotope analysis was performed under growth on glucose, xylose, and arabinose. Results indicate that PKP utilization increased with increasing xylose concentration and this trend was further pronounced during growth on arabinose. This was confirmed by mutation of the gene encoding XFP, which almost completely abolished flux through the PKP during growth on arabinose and resulted in decreased acetate:butyrate ratios. We discuss these experimental and computational results here, and the implications for our understanding of sugar metabolism in C. acetobutylicum.

  9. Arabinose 5-phosphate isomerase as a target for antibacterial design: studies with substrate analogues and inhibitors.

    PubMed

    Gabrielli, Luca; Merlo, Silvia; Airoldi, Cristina; Sperandeo, Paola; Gianera, Serena; Polissi, Alessandra; Nicotra, Francesco; Holler, Tod P; Woodard, Ronald W; Cipolla, Laura

    2014-04-15

    Structural requirements of D-arabinose 5-phosphate isomerase (KdsD, E.C. 5.3.1.13) from Pseudomonas aeruginosa were analysed in detail using advanced NMR techniques. We performed epitope mapping studies of the binding between the enzyme and the most potent KdsD inhibitors found to date, together with studies of a set of newly synthesised arabinose 5-phosphate (A5P) mimetics. We report here the first experimental evidence that KdsD may bind the furanose form of A5P, suggesting that catalysis of ring opening may be an important part of KdsD catalysis. PMID:24680056

  10. Improved starch recovery from potatoes by enzymes and reduced water holding of the residual fibres.

    PubMed

    Ramasamy, Urmila R; Lips, Steef; Bakker, Rob; Gruppen, Harry; Kabel, Mirjam A

    2014-11-26

    During the industrial extraction of starch from potatoes (Seresta), some starch remains within undisrupted potato cells in the fibrous side-stream. The aim of this study was to investigate if enzymatic degradation of cell wall polysaccharides (CWPs) can enhance starch recovery and lower the water holding capacity (WHC) of the "fibre" fraction. The use of a pectinase-rich preparation recovered 58% of the starch present in the "fibre" fraction. Also, the "fibre" fraction retained only 40% of the water present in the non-enzyme treated "fibre". This was caused by the degradation of pectins, in particular arabinogalactan side chains calculated as the sum of galactosyl and arabinosyl residues. PMID:25256483

  11. Reducing soluble phosphorus in dairy effluents through application of mine drainage residuals

    USGS Publications Warehouse

    Sibrell, Philip L.; Penn, Chad J.; Hedin, Robert S.

    2015-01-01

    Three different dairy manure wastewater effluent samples were amended with mine drainage residuals (MDR) to evaluate the suitability of MDR for sequestration of phosphorus (P). Geochemical modeling of the manure wastewater compositions indicated that partially soluble P-bearing minerals including hydroxyapatite, octacalcium phosphate, and vivianite were all oversaturated in each of the manure wastewater samples. Initial MDR amendment test results indicated that these partially soluble P minerals suspended in the wastewater replenished P in the water phase as it was sorbed by the MDR samples. Further investigations revealed that the MDR samples were effective in decreasing soluble P when the amended manure was tested using the water-extractable P procedure. Under these conditions, up to 90 percent of the soluble P in the manure was converted to a sorbed, water-insoluble state. Water contamination and large-scale validation tests of the process were also conducted.

  12. Thermal-hydraulic processes involved in loss of residual heat removal during reduced inventory operation

    SciTech Connect

    Fletcher, C.D.; McHugh, P.R.; Naff, S.A.; Johnsen, G.W.

    1991-02-01

    This paper identifies the topics needed to understand pressurized water reactor response to an extended loss of residual heat removal event during refueling and maintenance outages. By identifying the possible plant conditions and cooling methods that would be used for each cooling mode, the controlling thermal-hydraulic processes and phenomena were identified. Controlling processes and phenomena include: gravity drain, core water boil-off, and reflux cooling processes. Important subcategories of the reflux cooling processes include: the initiation of reflux cooling from various plant conditions, the effects of air on reflux cooling, core level depression effects, issues regarding the steam generator secondaries, and the special case of boiler-condenser cooling with once-through steam generators. 25 refs., 6 figs., 1 tab.

  13. Arabinose and xylose fermentation by recombinant Saccharomyces cerevisiae expressing a fungal pentose utilization pathway

    PubMed Central

    Bettiga, Maurizio; Bengtsson, Oskar; Hahn-Hägerdal, Bärbel; Gorwa-Grauslund, Marie F

    2009-01-01

    Background Sustainable and economically viable manufacturing of bioethanol from lignocellulose raw material is dependent on the availability of a robust ethanol producing microorganism, able to ferment all sugars present in the feedstock, including the pentose sugars L-arabinose and D-xylose. Saccharomyces cerevisiae is a robust ethanol producer, but needs to be engineered to achieve pentose sugar fermentation. Results A new recombinant S. cerevisiae strain expressing an improved fungal pathway for the utilization of L-arabinose and D-xylose was constructed and characterized. The new strain grew aerobically on L-arabinose and D-xylose as sole carbon sources. The activities of the enzymes constituting the pentose utilization pathway(s) and product formation during anaerobic mixed sugar fermentation were characterized. Conclusion Pentose fermenting recombinant S. cerevisiae strains were obtained by the expression of a pentose utilization pathway of entirely fungal origin. During anaerobic fermentation the strain produced biomass and ethanol. L-arabitol yield was 0.48 g per gram of consumed pentose sugar, which is considerably less than previously reported for D-xylose reductase expressing strains co-fermenting L-arabinose and D-xylose, and the xylitol yield was 0.07 g per gram of consumed pentose sugar. PMID:19630951

  14. A new method to reduce false positives due to antimony in detection of gunshot residues.

    PubMed

    Aksoy, Çağdaş; Bora, Taner; Şenocak, Nilgün; Aydın, Fırat

    2015-05-01

    False positives due to the presence of antimony in vehicle seat fabrics are a problem in gunshot residue (GSR) analysis, in particular, when graphite furnace atomic absorption spectrometry (GFAAS) is employed. In this study, we sought to determine the reason for the prevalence of false positive results and to propose a new approach for the analysis of GSR on vehicle seats. GFAAS was used to examine adhesive tape swabs collected from 100 seats of 50 different automobiles. Characterization of seat fabrics was carried out by using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy with energy dispersive X-ray (SEM/EDX) spectroscopy. The results of FTIR analysis indicated that all seat covers containing antimony were composed of polyester. Experimental results obtained by SEM/EDX analysis revealed that the fabrics in these seat covers contained evenly distributed antimony within the structure of polyester fibers. This study shows that the type of seat fabric should be determined by FTIR spectroscopy before elemental GSR analysis. In this way, most of the false positives caused by polyester fibers in GSR analysis can be prevented. PMID:25828380

  15. Genetic engineering and improvement of a Zymomonas mobilis for arabinose utilization and its performance on pretreated corn stover hydrolyzate

    DOE PAGESBeta

    Chou, Yat -Chen; Linger, Jeffrey; Yang, Shihui; Zhang, Min

    2015-04-28

    In this paper, a glucose, xylose and arabinose utilizing Zymomonas mobilis strain was constructed by incorporating arabinose catabolic pathway genes, araBAD encoding L-ribulokinase, L-arabinose isomerase and L-ribulose-5-phosphate- 4-epimerase in a glucose, xylose co-fermenting host, 8b, using a transposition integration approach. Further improvement on this arabinose-capable integrant, 33C was achieved by applying a second transposition to create a genomic knockout (KO) mutant library. Using arabinose as a sole carbon source and a selection pressure, the KO library was subjected to a growth-enrichment process involving continuous sub-culturing for over 120 generations. Strain 13-1-17, isolated from such process demonstrated significant improvement in metabolizingmore » arabinose in a dilute acid pretreated, saccharified corn stover slurry. Through Next Generation Sequencing (NGS) analysis, integration sites of the transposons were identified. Furthermore, multiple additional point mutations (SNPs: Single Nucleotide Polymorphisms) were discovered in 13-1-17, affecting genes araB and RpiB in the genome. Finally, we speculate that these mutations may have impacted the expression of the enzymes coded by these genes, ribulokinase and Ribose 5-P-isomerase, thus attributing to the improvement of the arabinose utilization.« less

  16. Structure of the thermophilic l-Arabinose isomerase from Geobacillus kaustophilus reveals metal-mediated intersubunit interactions for activity and thermostability.

    PubMed

    Choi, Jin Myung; Lee, Yong-Jik; Cao, Thinh-Phat; Shin, Sun-Mi; Park, Min-Kyu; Lee, Han-Seung; di Luccio, Eric; Kim, Seong-Bo; Lee, Sang-Jae; Lee, Sang Jun; Lee, Sung Haeng; Lee, Dong-Woo

    2016-04-15

    Thermophilic l-arabinose isomerase (AI), which catalyzes the interconversion of l-arabinose and l-ribulose, can be used to produce d-tagatose, a sugar substitute, from d-galactose. Unlike mesophilic AIs, thermophilic AIs are highly dependent on divalent metal ions for their catalytic activity and thermostability at elevated temperatures. However, the molecular basis underlying the substrate preferences and metal requirements of multimeric AIs remains unclear. Here we report the first crystal structure of the apo and holo forms of thermophilic Geobacillus kaustophilus AI (GKAI) in hexamer form. The structures, including those of GKAI in complex with l-arabitol, and biochemical analyses revealed not only how the substrate-binding site of GKAI is formed through displacement of residues at the intersubunit interface when it is bound to Mn(2+), but also revealed the water-mediated H-bonding networks that contribute to the structural integrity of GKAI during catalysis. These observations suggest metal-mediated isomerization reactions brought about by intersubunit interactions at elevated temperatures are responsible for the distinct active site features that promote the substrate specificity and thermostability of thermophilic AIs. PMID:26946941

  17. Reducing the impurity incorporation from residual gas by ion bombardment during high vacuum magnetron sputtering

    SciTech Connect

    Rosen, Johanna; Widenkvist, Erika; Larsson, Karin; Kreissig, Ulrich; Mraz, Stanislav; Martinez, Carlos; Music, Denis; Schneider, J. M.

    2006-05-08

    The influence of ion energy on the hydrogen incorporation has been investigated for alumina thin films, deposited by reactive magnetron sputtering in an Ar/O{sub 2}/H{sub 2}O environment. Ar{sup +} with an average kinetic energy of {approx}5 eV was determined to be the dominating species in the plasma. The films were analyzed with x-ray diffraction, x-ray photoelectron spectroscopy, and elastic recoil detection analysis, demonstrating evidence for amorphous films with stoichiometric O/Al ratio. As the substrate bias potential was increased from -15 V (floating potential) to -100 V, the hydrogen content decreased by {approx}70%, from 9.1 to 2.8 at. %. Based on ab initio calculations, these results may be understood by thermodynamic principles, where a supply of energy enables surface diffusion, H{sub 2} formation, and desorption [Rosen et al., J. Phys.: Condens. Matter 17, L137 (2005)]. These findings are of importance for the understanding of the correlation between ion energy and film composition and also show a pathway to reduce impurity incorporation during film growth in a high vacuum ambient.

  18. Identification and catalytic residues of the arsenite methyltransferase from a sulfate-reducing bacterium, Clostridium sp. BXM.

    PubMed

    Wang, Pei-Pei; Bao, Peng; Sun, Guo-Xin

    2015-01-01

    Arsenic methylation is an important process frequently occurring in anaerobic environments. Anaerobic microorganisms have been implicated as the major contributors for As methylation. However, very little information is available regarding the enzymatic mechanism of As methylation by anaerobes. In this study, one novel sulfate-reducing bacterium isolate, Clostridium sp. BXM, which was isolated from a paddy soil in our laboratory, was demonstrated to have the ability of methylating As. One putative arsenite S-Adenosyl-Methionine methyltransferase (ArsM) gene, CsarsM was cloned from Clostridium sp. BXM. Heterologous expression of CsarsM conferred As resistance and the ability of methylating As to an As-sensitive strain of Escherichia coli. Purified methyltransferase CsArsM catalyzed the formation of methylated products from arsenite, further confirming its function of As methylation. Site-directed mutagenesis studies demonstrated that three conserved cysteine residues at positions 65, 153 and 203 in CsArsM are necessary for arsenite methylation, but only Cysteine 153 and Cysteine 203 are required for the methylation of monomethylarsenic to dimethylarsenic. These results provided the characterization of arsenic methyltransferase from anaerobic sulfate-reducing bacterium. Given that sulfate-reducing bacteria are ubiquitous in various wetlands including paddy soils, enzymatic methylation mediated by these anaerobes is proposed to contribute to the arsenic biogeochemical cycling. PMID:25790486

  19. Long Term Sugarcane Crop Residue Retention Offers Limited Potential to Reduce Nitrogen Fertilizer Rates in Australian Wet Tropical Environments

    PubMed Central

    Meier, Elizabeth A.; Thorburn, Peter J.

    2016-01-01

    The warming of world climate systems is driving interest in the mitigation of greenhouse gas (GHG) emissions. In the agricultural sector, practices that mitigate GHG emissions include those that (1) reduce emissions [e.g., those that reduce nitrous oxide (N2O) emissions by avoiding excess nitrogen (N) fertilizer application], and (2) increase soil organic carbon (SOC) stocks (e.g., by retaining instead of burning crop residues). Sugarcane is a globally important crop that can have substantial inputs of N fertilizer and which produces large amounts of crop residues (‘trash’). Management of N fertilizer and trash affects soil carbon and nitrogen cycling, and hence GHG emissions. Trash has historically been burned at harvest, but increasingly is being retained on the soil surface as a ‘trash blanket’ in many countries. The potential for trash retention to alter N fertilizer requirements and sequester SOC was investigated in this study. The APSIM model was calibrated with data from field and laboratory studies of trash decomposition in the wet tropics of northern Australia. APSIM was then validated against four independent data sets, before simulating location × soil × fertilizer × trash management scenarios. Soil carbon increased in trash blanketed soils relative to SOC in soils with burnt trash. However, further increases in SOC for the study region may be limited because the SOC in trash blanketed soils could be approaching equilibrium; future GHG mitigation efforts in this region should therefore focus on N fertilizer management. Simulated N fertilizer rates were able to be reduced from conventional rates regardless of trash management, because of low yield potential in the wet tropics. For crops subjected to continuous trash blanketing, there was substantial immobilization of N in decomposing trash so conventional N fertilizer rates were required for up to 24 years after trash blanketing commenced. After this period, there was potential to reduce N

  20. Long Term Sugarcane Crop Residue Retention Offers Limited Potential to Reduce Nitrogen Fertilizer Rates in Australian Wet Tropical Environments.

    PubMed

    Meier, Elizabeth A; Thorburn, Peter J

    2016-01-01

    The warming of world climate systems is driving interest in the mitigation of greenhouse gas (GHG) emissions. In the agricultural sector, practices that mitigate GHG emissions include those that (1) reduce emissions [e.g., those that reduce nitrous oxide (N2O) emissions by avoiding excess nitrogen (N) fertilizer application], and (2) increase soil organic carbon (SOC) stocks (e.g., by retaining instead of burning crop residues). Sugarcane is a globally important crop that can have substantial inputs of N fertilizer and which produces large amounts of crop residues ('trash'). Management of N fertilizer and trash affects soil carbon and nitrogen cycling, and hence GHG emissions. Trash has historically been burned at harvest, but increasingly is being retained on the soil surface as a 'trash blanket' in many countries. The potential for trash retention to alter N fertilizer requirements and sequester SOC was investigated in this study. The APSIM model was calibrated with data from field and laboratory studies of trash decomposition in the wet tropics of northern Australia. APSIM was then validated against four independent data sets, before simulating location × soil × fertilizer × trash management scenarios. Soil carbon increased in trash blanketed soils relative to SOC in soils with burnt trash. However, further increases in SOC for the study region may be limited because the SOC in trash blanketed soils could be approaching equilibrium; future GHG mitigation efforts in this region should therefore focus on N fertilizer management. Simulated N fertilizer rates were able to be reduced from conventional rates regardless of trash management, because of low yield potential in the wet tropics. For crops subjected to continuous trash blanketing, there was substantial immobilization of N in decomposing trash so conventional N fertilizer rates were required for up to 24 years after trash blanketing commenced. After this period, there was potential to reduce N fertilizer

  1. Comparing the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways in arabinose and xylose fermenting Saccharomyces cerevisiae strains

    PubMed Central

    Bettiga, Maurizio; Hahn-Hägerdal, Bärbel; Gorwa-Grauslund, Marie F

    2008-01-01

    Background Ethanolic fermentation of lignocellulosic biomass is a sustainable option for the production of bioethanol. This process would greatly benefit from recombinant Saccharomyces cerevisiae strains also able to ferment, besides the hexose sugar fraction, the pentose sugars, arabinose and xylose. Different pathways can be introduced in S. cerevisiae to provide arabinose and xylose utilisation. In this study, the bacterial arabinose isomerase pathway was combined with two different xylose utilisation pathways: the xylose reductase/xylitol dehydrogenase and xylose isomerase pathways, respectively, in genetically identical strains. The strains were compared with respect to aerobic growth in arabinose and xylose batch culture and in anaerobic batch fermentation of a mixture of glucose, arabinose and xylose. Results The specific aerobic arabinose growth rate was identical, 0.03 h-1, for the xylose reductase/xylitol dehydrogenase and xylose isomerase strain. The xylose reductase/xylitol dehydrogenase strain displayed higher aerobic growth rate on xylose, 0.14 h-1, and higher specific xylose consumption rate in anaerobic batch fermentation, 0.09 g (g cells)-1 h-1 than the xylose isomerase strain, which only reached 0.03 h-1 and 0.02 g (g cells)-1h-1, respectively. Whereas the xylose reductase/xylitol dehydrogenase strain produced higher ethanol yield on total sugars, 0.23 g g-1 compared with 0.18 g g-1 for the xylose isomerase strain, the xylose isomerase strain achieved higher ethanol yield on consumed sugars, 0.41 g g-1 compared with 0.32 g g-1 for the xylose reductase/xylitol dehydrogenase strain. Anaerobic fermentation of a mixture of glucose, arabinose and xylose resulted in higher final ethanol concentration, 14.7 g l-1 for the xylose reductase/xylitol dehydrogenase strain compared with 11.8 g l-1 for the xylose isomerase strain, and in higher specific ethanol productivity, 0.024 g (g cells)-1 h-1 compared with 0.01 g (g cells)-1 h-1 for the xylose reductase

  2. Efficient Synthesis of 4-Amino-4-deoxy-L-arabinose and Spacer-equipped 4-Amino-4-deoxy-L-arabinopyranosides by Transglycosylation Reactions.

    PubMed

    Müller, Bernhard; Blaukopf, Markus; Hofinger, Andreas; Zamyatina, Alla; Brade, Helmut; Kosma, Paul

    2010-09-01

    Methyl 4-azido-4-deoxy-β-L-arabinopyranoside has been synthesized in five steps starting from methyl β-D-xylopyranoside in a multigram scale without chromatographic purification in 78% overall yield. The transformation relied on selective tosylation/nosylation at O-4 followed by acylation, S(N)2 displacement with sodium azide and subsequent deprotection. The methyl 4-azido-4-deoxy-arabinoside was then converted into allyl, propenyl, ω-bromohexyl and chlorethoxyethyl spacer glycosides by transglycosylation with the respective alcohols in good yields and fair anomeric selectivity. Reduction of the azido group and further transformations of the aglycon afforded ω-thiol-containing spacer derivatives. Coupling to maleimide-activated BSA provided a potent immunogen which was used to generate murine and rabbit polyclonal sera binding to LPS-core epitopes containing 4-amino-4-deoxy-arabinose residues. PMID:22187517

  3. Use of drinking water treatment residuals as a potential best management practice to reduce phosphorus risk index scores.

    PubMed

    Dayton, E A; Basta, N T

    2005-01-01

    The P risk index system has been developed to identify agricultural fields vulnerable to P loss as a step toward protecting surface water. Because of their high Langmuir phosphorus adsorption maxima (P(max)), use of drinking water treatment residuals (WTRs) should be considered as a best management practice (BMP) to lower P risk index scores. This work discusses three WTR application methods that can be used to reduce P risk scores: (i) enhanced buffer strip, (ii) incorporation into a high soil test phosphorus (STP) soil, and (iii) co-blending with manure or biosolids. The relationship between WTR P(max) and reduction in P extractability and runoff P was investigated. In a simulated rainfall experiment, using a buffer strip enhanced with 20 Mg WTR ha(-1), runoff P was reduced by from 66.8 to 86.2% and reductions were related to the WTR P(max). When 25 g kg(-1) WTR was incorporated into a high STP soil of 315 mg kg(-1) determined using Mehlich-3 extraction, 0.01 M calcium chloride-extractable phosphorus (CaCl(2)-P) reductions ranged from 60.9 to 96.0% and were strongly (P < 0.01) related to WTR P(max). At a 100 g kg(-1) WTR addition, Mehlich 3-extractable P reductions ranged from 41.1 to 86.7% and were strongly (P < 0.01) related to WTR P(max). Co-blending WTR at 250 g kg(-1) to manure or biosolids reduced CaCl(2)-P by >75%. The WTR P(max) normalized across WTR application rates (P(max) x WTR application) was significantly related to reductions in CaCl(2)-P or STP. Using WTR as a P risk index modifying factor will promote effective use of WTR as a BMP to reduce P loss from agricultural land. PMID:16275711

  4. Structure of the effector-binding domain of the arabinose repressor AraR from Bacillus subtilis

    SciTech Connect

    Procházková, Kateřina; Čermáková, Kateřina; Pachl, Petr; Sieglová, Irena; Fábry, Milan; Otwinowski, Zbyszek; Řezáčová, Pavlína

    2012-02-01

    The crystal structure of the effector-binding domain of the transcriptional repressor AraR from B. subtilis in complex with the effector molecule (l-arabinose) was determined at 2.2 Å resolution. A detailed analysis of the crystal identified a dimer organization that is distinctive from that of other members of the GalR/LacI family. In Bacillus subtilis, the arabinose repressor AraR negatively controls the expression of genes in the metabolic pathway of arabinose-containing polysaccharides. The protein is composed of two domains of different phylogenetic origin and function: an N-terminal DNA-binding domain belonging to the GntR family and a C-terminal effector-binding domain that shows similarity to members of the GalR/LacI family. The crystal structure of the C-terminal effector-binding domain of AraR in complex with the effector l-arabinose has been determined at 2.2 Å resolution. The l-arabinose binding affinity was characterized by isothermal titration calorimetry and differential scanning fluorimetry; the K{sub d} value was 8.4 ± 0.4 µM. The effect of l-arabinose on the protein oligomeric state was investigated in solution and detailed analysis of the crystal identified a dimer organization which is distinctive from that of other members of the GalR/LacI family.

  5. Properties of d-Arabinose Isomerase Purified from Two Strains of Escherichia coli

    PubMed Central

    Boulter, James R.; Gielow, William O.

    1973-01-01

    d-Arabinose isomerase (EC 5.3.1.3) has been isolated from l-fucose-induced cultures of Escherichia coli K-12 and d-arabinose-induced cultures of E. coli B/r. Both enzymes were homogeneous in an ultracentrifuge and migrated as single bands upon disc electrophoresis in acrylamide gels. The s20,w was 14.5 × 10−13 sec for the E. coli K-12 enzyme and 14.3 × 10−13 sec for the E. coli B/r enzyme. The molecular weight, determined by high-speed sedimentation equilibrium, was 3.55 ± 0.06 × 105 for the E. coli K-12 enzyme and 3.42 ± 0.04 × 105 for the enzyme isolated from E. coli B/r. Both enzyme preparations were active wth l-fucose or d-arabinose as substrates and showed no activity on any of the other aldopentoses or aldohexoses tested. With the E. coli K-12 enzyme, the Km was 2.8 × 10−1m for d-arabinose and 4.5 × 10−2m for l-fucose; with the E. coli B/r enzyme, the Km was 1.7 × 10−1m for d-arabinose and 4.2 × 10−2m for l-fucose. Both enzymes were inhibited by several of the polyalcohols tested, ribitol, l-arabitol, and dulcitol being the strongest. Both enzymes exhibited a broad plateau of optimal catalytic activity in the alkaline range. Both enzymes were stimulated by the presence of Mn2+ or Co2+ ions, but were strongly inhibited by the presence of Cd2+ ions. Both enzymes were precipitated by antisera prepared against either enzyme preparation. The amino acid composition for both proteins has been determined; a striking similarity has been detected. Both enzymes could be dissociated, by protonation at pH 2 or by dialysis against buffer containing 8 m urea, into subunits that were homogeneous in an ultracentrifuge and migrated as single bands on disc electrophoresis in acrylamide gels containing urea. The molecular weight of the subunit, determined by high-speed sedimentation equilibrium, was 9.09 ± 0.2 × 104 for the enzyme from E. coli K-12 and 8.46 ± 0.1 × 104 for the enzyme from E. coli B/r. On the basis of biophysical studies, both

  6. Hepatitis C Virus (HCV) Envelope Glycoproteins E1 and E2 Contain Reduced Cysteine Residues Essential for Virus Entry*

    PubMed Central

    Fraser, Johanna; Boo, Irene; Poumbourios, Pantelis; Drummer, Heidi E.

    2011-01-01

    The HCV envelope glycoproteins E1 and E2 contain eight and 18 highly conserved cysteine residues, respectively. Here, we examined the oxidation state of E1E2 heterodimers incorporated into retroviral pseudotyped particles (HCVpp) and investigated the significance of free sulfhydryl groups in cell culture-derived HCV (HCVcc) and HCVpp entry. Alkylation of free sulfhydryl groups on HCVcc/pp with a membrane-impermeable sulfhydryl-alkylating reagent 4-(N-maleimido)benzyl-α-trimethylammonium iodide (M135) prior to virus attachment to cells abolished infectivity in a dose-dependent manner. Labeling of HCVpp envelope proteins with EZ-Link maleimide-PEG2-biotin (maleimide-biotin) detected free thiol groups in both E1 and E2. Unlike retroviruses that employ disulfide reduction to facilitate virus entry, the infectivity of alkylated HCVcc could not be rescued by addition of exogenous reducing agents. Furthermore, the infectivity of HCVcc bound to target cells was not affected by addition of M135 indicative of a change in glycoprotein oxidation state from reduced to oxidized following virus attachment to cells. By contrast, HCVpp entry was reduced by 61% when treated with M135 immediately following attachment to cells, suggesting that the two model systems might demonstrate variations in oxidation kinetics. Glycoprotein oxidation was not altered following binding of HCVpp incorporated E1E2 to soluble heparin or recombinant CD81. These results suggest that HCV entry is dependent on the presence of free thiol groups in E1 and E2 prior to cellular attachment and reveals a new essential component of the HCV entry process. PMID:21768113

  7. Hepatitis C virus (HCV) envelope glycoproteins E1 and E2 contain reduced cysteine residues essential for virus entry.

    PubMed

    Fraser, Johanna; Boo, Irene; Poumbourios, Pantelis; Drummer, Heidi E

    2011-09-16

    The HCV envelope glycoproteins E1 and E2 contain eight and 18 highly conserved cysteine residues, respectively. Here, we examined the oxidation state of E1E2 heterodimers incorporated into retroviral pseudotyped particles (HCVpp) and investigated the significance of free sulfhydryl groups in cell culture-derived HCV (HCVcc) and HCVpp entry. Alkylation of free sulfhydryl groups on HCVcc/pp with a membrane-impermeable sulfhydryl-alkylating reagent 4-(N-maleimido)benzyl-α-trimethylammonium iodide (M135) prior to virus attachment to cells abolished infectivity in a dose-dependent manner. Labeling of HCVpp envelope proteins with EZ-Link maleimide-PEG2-biotin (maleimide-biotin) detected free thiol groups in both E1 and E2. Unlike retroviruses that employ disulfide reduction to facilitate virus entry, the infectivity of alkylated HCVcc could not be rescued by addition of exogenous reducing agents. Furthermore, the infectivity of HCVcc bound to target cells was not affected by addition of M135 indicative of a change in glycoprotein oxidation state from reduced to oxidized following virus attachment to cells. By contrast, HCVpp entry was reduced by 61% when treated with M135 immediately following attachment to cells, suggesting that the two model systems might demonstrate variations in oxidation kinetics. Glycoprotein oxidation was not altered following binding of HCVpp incorporated E1E2 to soluble heparin or recombinant CD81. These results suggest that HCV entry is dependent on the presence of free thiol groups in E1 and E2 prior to cellular attachment and reveals a new essential component of the HCV entry process. PMID:21768113

  8. Removal of the free cysteine residue reduces irreversible thermal inactivation of feruloyl esterase: evidence from circular dichroism and fluorescence spectra.

    PubMed

    Li, Jingjing; Zhang, Shuaibing; Yi, Zhuolin; Pei, Xiaoqiong; Wu, Zhongliu

    2015-08-01

    Feruloyl esterase A from Aspergillus niger (AnFaeA) contains three intramolecular disulfide bonds and one free cysteine at position 235. Saturated mutagenesis at Cys235 was carried out to produce five active mutants, all of which displayed unusual thermal inactivation patterns with the most residual activity achieved at 75°C, much higher than the parental AnFaeA. But their optimal reaction temperatures were lower than the parental AnFaeA. Extensive investigation into their free thiol and disulfide bond, circular dichroism spectra and fluorescence spectra revealed that the unfolding of the parental enzyme was irreversible on all the tested conditions, while that of the Cys235 mutants was reversible, and their ability to refold was highly dependent on the denaturing temperature. Mutants denatured at 75°C were able to efficiently reverse the unfolding to regain native structure during the cooling process. This study provided valid evidence that free cysteine substitutions can reduce irreversible thermal inactivation of proteins. PMID:26079173

  9. Random-type scanning patterns in laser shock peening without absorbing coating in 2024-T351 Al alloy: A solution to reduce residual stress anisotropy

    NASA Astrophysics Data System (ADS)

    Correa, C.; Peral, D.; Porro, J. A.; Díaz, M.; Ruiz de Lara, L.; García-Beltrán, A.; Ocaña, J. L.

    2015-10-01

    Laser Shock Peening (LSP) is considered as an alternative technology to shot peening (SP) for the induction of compressive residual stresses in metallic alloys in order to improve their fatigue, corrosion and wear resistance. Since laser pulses generated by high-intensity laser systems cover only a small area, laser pulses are generally overlapped and scanned in a zigzag-type pattern to cover completely the surface to be treated. However, zigzag-type scanning patterns induce residual stress anisotropy as collateral effect. The purpose of this paper is to describe and explain, for the first time and with the aid of the numerical model developed by the authors, the influence of the scanning pattern directionality on the residual stress tensor. As an effective solution, the authors propose the application of random-type scanning patterns instead of zigzag-type in order to reduce the mentioned residual stress anisotropy.

  10. A mixed diet supplemented with L-arabinose does not alter glycaemic or insulinaemic responses in healthy human subjects.

    PubMed

    Halschou-Jensen, Kia; Bach Knudsen, Knud E; Nielsen, Søren; Bukhave, Klaus; Andersen, Jens R

    2015-01-14

    In addition to a yet-to-be published study showing arabinose to have an inhibiting effect on maltase, in vitro studies have shown L-arabinose to exert an inhibiting effect on small-intestinal sucrase and maltase and the consumption of a sucrose-rich drink containing L-arabinose to exert positive effects on postprandial blood glucose, insulin and C-peptide responses in humans. However, the effects of adding L-arabinose to mixed meals on the indices of glucose control are unknown. The purpose of the present study was to investigate whether the positive effects of L-arabinose added to a sugar drink could be reproduced in subjects consuming a mixed meal containing sucrose and/or starch from wheat flour. A total of seventeen healthy men participated in study 1, a randomised, double-blind, cross-over trial. In this study, the subjects consumed two different breakfast meals containing sucrose and starch from wheat flour (meal A) or starch from wheat flour (meal B) supplemented with 0, 5 and 10 % L-arabinose by weight after a 12 h fast. A total of six healthy men participated in study 2, a randomised, double-blind, cross-over trial. In this study, the subjects also consumed meal B served in two different textures and a liquid meal with maltose supplemented with 0 and 20% L-arabinose. In addition, 1·5 g of paracetamol was chosen as an indirect marker to assess gastric emptying. Postprandial plasma glucose, insulin and C-peptide concentrations were measured regularly for 3 h. The results of the present study showed that the peak plasma concentration, time to reach peak plasma concentration or AUC values of glucose, insulin and C-peptide were not altered after consumption of the test meals. Overall, it was not possible to reproduce the beneficial effects of L-arabinose added to sucrose drinks when L-arabinose was mixed in a solid or semi-solid mixed meal. PMID:25400106

  11. Web-Based Intervention in Mindfulness Meditation for Reducing Residual Depressive Symptoms and Relapse Prophylaxis: A Qualitative Study

    PubMed Central

    2014-01-01

    Background Mindful Mood Balance (MMB) is a Web-based intervention designed to treat residual depressive symptoms and prevent relapse. MMB was designed to deliver the core concepts of mindfulness-based cognitive therapy (MBCT), a group treatment, which, despite its strong evidence base, faces a number of dissemination challenges. Objective The present study is a qualitative investigation of participants’ experiences with MMB. Methods Qualitative content analysis was conducted via 38 exit interviews with MMB participants. Study inclusion required a current PHQ-9 (Patient Health Questionnaire) score ≤12 and lifetime history ≥1 major depressive episode. Feedback was obtained on specific website components, program content, and administration as well as skills learned. Results Codes were assigned to interview responses and organized into four main themes: MBCT Web content, MBCT Web-based group process, home practice, and evidence of concept comprehension. Within these four areas, participants highlighted the advantages and obstacles of translating and delivering MBCT in a Web-based format. Adding increased support was suggested for troubleshooting session content as well as managing time challenges for completing home mindfulness practice. Participants endorsed developing affect regulation skills and identified several advantages to Web-based delivery including flexibility, reduced cost, and time commitment. Conclusions These findings support the viability of providing MBCT online and are consistent with prior qualitative accounts derived from in-person MBCT groups. While there is certainly room for innovation in the domains of program support and engagement, the high levels of participant satisfaction indicated that MMB can significantly increase access to evidence-based psychological treatments for sub-threshold symptoms of unipolar affective disorder. PMID:24662625

  12. Analysis of the Arabinose-5-Phosphate Isomerase of Bacteroides fragilis Provides Insight into Regulation of Single-Domain Arabinose Phosphate Isomerases

    PubMed Central

    Cech, David; Wang, Pan Fen; Holler, Tod P.

    2014-01-01

    Arabinose-5-phosphate isomerases (APIs) catalyze the interconversion of d-ribulose-5-phosphate and d-arabinose-5-phosphate, the first step in the biosynthesis of 3-deoxy-d-manno-octulosonic acid (Kdo), an essential component of the lipopolysaccharide in Gram-negative bacteria. Classical APIs, such as Escherichia coli KdsD, contain a sugar isomerase domain and a tandem cystathionine beta-synthase domain. Despite substantial effort, little is known about structure-function relationships in these APIs. We recently reported an API containing only a sugar isomerase domain. This protein, c3406 from E. coli CFT073, has no known physiological function. In this study, we investigated a putative single-domain API from the anaerobic Gram-negative bacterium Bacteroides fragilis. This putative API (UniProt ID Q5LIW1) is the only protein encoded by the B. fragilis genome with significant identity to any known API, suggesting that it is responsible for lipopolysaccharide biosynthesis in B. fragilis. We tested this hypothesis by preparing recombinant Q5LIW1 protein (here referred to by the UniProt ID Q5LIW1), characterizing its API activity in vitro, and demonstrating that the gene encoding Q5LIW1 (GenBank ID YP_209877.1) was able to complement an API-deficient E. coli strain. We demonstrated that Q5LIW1 is inhibited by cytidine 5′-monophospho-3-deoxy-d-manno-2-octulosonic acid, the final product of the Kdo biosynthesis pathway, with a Ki of 1.91 μM. These results support the assertion that Q5LIW1 is the API that supports lipopolysaccharide biosynthesis in B. fragilis and is subject to feedback regulation by CMP-Kdo. The sugar isomerase domain of E. coli KdsD, lacking the two cystathionine beta-synthase domains, demonstrated API activity and was further characterized. These results suggest that Q5LIW1 may be a suitable system to study API structure-function relationships. PMID:24891442

  13. ASCORBIC ACID TREATMENT TO REDUCE RESIDUAL HALOGEN-BASED OXIDANTS PRIOR TO THE DETERMINATION OF HALOGENATED DISINFECTION BYPRODUCTS IN POTABLE WATER

    EPA Science Inventory

    Treatment of potable water samples with ascorbic acid has been investigated as a means for reducing residual halogen-based oxidants (disinfectants)i.e., HOCl, Cl2, Brw and BrCl, prior to determination of EPA Method 551.1A and 551.1B analytes. These disinfection byproducts include...

  14. Effect of Dietary l-arabinose on the Intestinal Microbiota and Metabolism of Dietary Daidzein in Adult Mice

    PubMed Central

    TAMURA, Motoi; KURUSU, Yukie; HORI, Sachiko

    2012-01-01

    This study examined the effects of L-arabinose on mouse intestinal microbiota and urinary isoflavonoids. Male mice were randomly divided into two groups: those fed a 0.05% daidzein–2.5% L-arabinose diet (AR group) and those fed a 0.05% daidzein control diet (CO group) for 28 days. The amounts of daidzein detected in urine were significantly lower in the AR group than in the CO group. The ratio of equol/daidzein was significantly higher in the AR group (p<0.01) than in the CO group. The composition of caecal flora differed between the AR and CO groups. The occupation ratios of Prevotella and Lactobacillales were significantly lower in the AR group. This study suggests that dietary L-arabinose has the potential to affect the metabolism of equol from daidzein by altering the metabolic activity of intestinal microbiota. PMID:24936350

  15. Uptake and Metabolic Fate of Glucose, Arabinose, and Xylose by Zea mays Coleoptiles in Relation to Cell Wall Synthesis 1

    PubMed Central

    Carpita, Nicholas C.; Brown, Ronald A.; Weller, Kathleen M.

    1982-01-01

    According to the acid-growth hypothesis, auxin-induced secretion of hydrogen ions activate “wall loosening” enzymes that change the rheological properties of the cell wall. The wall loosening process may yield monosaccharides by the enzymic cleavage of load-bearing polysaccharides. Our study was initiated to determine the metabolic fate of such sugars when released from the major hemicellulosic polysaccharides of the cell walls of Zea mays coleoptiles. Excised coleoptile sections accumulated radioactive glucose, arabinose, and xylose supplied in an incubation medium, and the radioactivity from these sugars was incorporated into polysaccharides. At least 50% of the radioactivity from glucose accumulated in the soluble neutral sugar fraction regardless of external concentrations. The distribution of radioactivity from xylose into all subcellular fractions was similar to that from glucose, indicating that xylose was converted to glucose before being used by the coleoptile. IAA increased the incorporation of glucose into cell wall polysaccharide and neutral sugar pools when the exogenous concentration was higher than 1 millimolar. Over 80% of the radioactivity from arabinose accumulated by the coleoptile sections was incorporated into soluble and noncellulosic polymers; IAA induced an increase in the incorporation of arabinose into noncellulosic polymers by 22%. Accumulation of radioactivity from arabinose into polysaccharide was enhanced by IAA at concentrations of exogenous arabinose up to 33 millimolar. IAA promoted the incorporation of both arabinose and glucose into cell wall polysaccharides even when elongation was inhibited by CaCl2, indicating that the influence of IAA was not a consequence of the growth response. PMID:16662366

  16. FORMATION OF FINE PARTICLES FROM RESIDUAL OIL COMBUSTION: REDUCING ULTRAFINE NUCLEI THROUGH THE ADDITION OF INORGANIC SORBENT

    EPA Science Inventory

    The paper gives results of an investigation, using an 82-kW-rated laboratory-scale refractory-lined combustor, of the characteristics of particulate matter emitted from residual oil combustion and the reduction of ultrafine nuclei by postflame sorbent injection. Without sorbent a...

  17. Industrial Saccharomyces cerevisiae Yeast Strain Engineered to Convert Glucose, Mannose, Arabinose, and Xylose (GMAX) to Ethanol Anaerobically

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Technology for engineering an industrial yeast strain for production of ethanol from glucose, mannose, arabinose, and xylose (GMAX-yeast) using both corn starch and cellulosic feedstocks with simultaneous production of valuable coproducts, including biodiesel, will be discussed. A stable industrial...

  18. Elastic/plastic analyses of advanced composites investigating the use of the compliant layer concept in reducing residual stresses resulting from processing

    NASA Technical Reports Server (NTRS)

    Arnold, Steven M.; Arya, Vinod K.; Melis, Matthew E.

    1990-01-01

    High residual stresses within intermetallic and metal matrix composite systems can develop upon cooling from the processing temperature to room temperature due to the coefficient of thermal expansion (CTE) mismatch between the fiber and matrix. As a result, within certain composite systems, radial, circumferential, and/or longitudinal cracks have been observed to form at the fiber-matrix interface. The compliant layer concept (insertion of a compensating interface material between the fiber and matrix) was proposed to reduce or eliminate the residual stress buildup during cooling and thus minimize cracking. The viability of the proposed compliant layer concept is investigated both elastically and elastoplastically. A detailed parametric study was conducted using a unit cell model consisting of three concentric cylinders to determine the required character (i.e., thickness and material properties) of the compliant layer as well as its applicability. The unknown compliant layer mechanical properties were expressed as ratios of the corresponding temperature dependent Ti-24Al-11Nb (a/o) matrix properties. The fiber properties taken were those corresponding to SCS-6 (SiC). Results indicate that the compliant layer can be used to reduce, if not eliminate, radial and circumferential residual stresses within the fiber and matrix and therefore also reduce or eliminate the radial cracking. However, with this decrease in in-plane stresses, one obtains an increase in longitudinal stress, thus potentially initiating longitudinal cracking. Guidelines are given for the selection of a specific compliant material, given a perfectly bonded system.

  19. Generation of organic acids and monosaccharides by hydrolytic and oxidative transformation of food processing residues.

    PubMed

    Fischer, Klaus; Bipp, Hans-Peter

    2005-05-01

    Carbohydrate-rich biomass residues, i.e. sugar beet molasses, whey powder, wine yeast, potato peel sludge, spent hops, malt dust and apple marc, were tested as starting materials for the generation of marketable chemicals, e.g. aliphatic acids, sugar acids and mono-/disaccharides. Residues were oxidized or hydrolyzed under acidic or alkaline conditions applying conventional laboratory digestion methods and microwave assisted techniques. Yields and compositions of the oxidation products differed according to the oxidizing agent used. Main products of oxidation by 30% HNO(3) were acetic, glucaric, oxalic and glycolic acids. Applying H(2)O(2)/CuO in alkaline solution, the organic acid yields were remarkably lower with formic, acetic and threonic acids as main products. Gluconic acid was formed instead of glucaric acid throughout. Reaction of a 10% H(2)O(2) solution with sugar beet molasses generated formic and lactic acids mainly. Na(2)S(2)O(8) solutions were very inefficient at oxidizing the residues. Glucose, arabinose and galactose were formed during acidic hydrolysis of malt dust and apple marc. The glucose content reached 0.35 g per gram of residue. Important advantages of the microwave application were lower reaction times and reduced reagent demands. PMID:15607197

  20. Genetic engineering and improvement of a Zymomonas mobilis for arabinose utilization and its performance on pretreated corn stover hydrolyzate

    SciTech Connect

    Chou, Yat -Chen; Linger, Jeffrey; Yang, Shihui; Zhang, Min

    2015-04-28

    In this paper, a glucose, xylose and arabinose utilizing Zymomonas mobilis strain was constructed by incorporating arabinose catabolic pathway genes, araBAD encoding L-ribulokinase, L-arabinose isomerase and L-ribulose-5-phosphate- 4-epimerase in a glucose, xylose co-fermenting host, 8b, using a transposition integration approach. Further improvement on this arabinose-capable integrant, 33C was achieved by applying a second transposition to create a genomic knockout (KO) mutant library. Using arabinose as a sole carbon source and a selection pressure, the KO library was subjected to a growth-enrichment process involving continuous sub-culturing for over 120 generations. Strain 13-1-17, isolated from such process demonstrated significant improvement in metabolizing arabinose in a dilute acid pretreated, saccharified corn stover slurry. Through Next Generation Sequencing (NGS) analysis, integration sites of the transposons were identified. Furthermore, multiple additional point mutations (SNPs: Single Nucleotide Polymorphisms) were discovered in 13-1-17, affecting genes araB and RpiB in the genome. Finally, we speculate that these mutations may have impacted the expression of the enzymes coded by these genes, ribulokinase and Ribose 5-P-isomerase, thus attributing to the improvement of the arabinose utilization.

  1. Boost the electron mobility of solution-grown organic single crystals via reducing the amount of polar solvent residues

    DOE PAGESBeta

    Xue, Guobiao; Xin, Huolin L.; Wu, Jiake; Fan, Congcheng; Liu, Shuang; Huang, Zhuoting; Liu, Yujing; Shan, Bowen; Miao, Qian; Chen, Hongzheng; et al

    2015-10-29

    Enhancing electron transport to match with the development in hole transport is critical for organic electronics in the future. As electron motion is susceptible to extrinsic factors, seeking these factors and avoiding their negative effects have become the central challenge. Here, the existence of polar solvent residues in solution-grown single-crystals of 6,13-bis(triisopropylsilylethynyl)-5,7,12,14-tetraazapentacene is identified as a factor detrimental to electron motion. Field-effect transistors of the crystals exhibit electron mobility boosted by about 60% after the residues are removed. The average electron mobility reaches up to 8.0 ± 2.2 cm2 V–1 s–1 with a highest value of 13.3 cm2 V–1 s–1;more » these results are significantly higher than those obtained previously for the same molecule (1.0–5.0 cm2 V–1 s–1). Furthermore, the achieved mobility is also higher than the maximum reported electron mobility for organic materials (11 cm2 V–1 s–1). As a result, this work should greatly accelerate the advancement of organic electron-transporting materials.« less

  2. Identification of GutQ from Escherichia coli as a d-Arabinose 5-Phosphate Isomerase

    PubMed Central

    Meredith, Timothy C.; Woodard, Ronald W.

    2005-01-01

    The glucitol operon (gutAEBDMRQ) of Escherichia coli encodes a phosphoenolpyruvate:sugar phosphotransferase system that metabolizes the hexitol d-glucitol (sorbitol). The functions for all but the last gene, gutQ, have been previously assigned. The high sequence similarity between GutQ and KdsD, a d-arabinose 5-phosphate isomerase (API) from the 3-deoxy-d-manno-octulosonate (KDO)-lipopolysaccharide (LPS) biosynthetic pathway, suggested a putative activity, but its role within the context of the gut operon remained unclear. Accordingly, the enzyme was cloned, overexpressed, and characterized. Recombinant GutQ was shown to indeed be a second copy of API from the E. coli K-12 genome with biochemical properties similar to those of KdsD, catalyzing the reversible aldol-ketol isomerization between d-ribulose 5-phosphate (Ru5P) and d-arabinose 5-phosphate (A5P). Genomic disruptions of each API gene were constructed in E. coli K-12. TCM11[(ΔkdsD)] was capable of sustaining essential LPS synthesis at wild-type levels, indicating that GutQ functions as an API inside the cell. The gut operon remained inducible in TCM7[(ΔgutQ)], suggesting that GutQ is not directly involved in d-glucitol catabolism. The conditional mutant TCM15[(ΔgutQΔkdsD)] was dependent on exogenous A5P both for LPS synthesis/growth and for upregulation of the gut operon. The phenotype was suppressed by complementation in trans with a plasmid encoding a functional copy of GutQ or by increasing the amount of A5P in the medium. As there is no obvious obligatory role for GutQ in the metabolism of d-glucitol and there is no readily apparent link between d-glucitol metabolism and LPS biosynthesis, it is suggested that A5P is not only a building block for KDO biosynthesis but also may be a regulatory molecule involved in expression of the gut operon. PMID:16199563

  3. Thermal-hydraulic processes involved in loss of residual heat removal during reduced inventory operation. Revision 1

    SciTech Connect

    Fletcher, C.D.; McHugh, P.R.; Naff, S.A.; Johnsen, G.W.

    1991-02-01

    This paper identifies the topics needed to understand pressurized water reactor response to an extended loss of residual heat removal event during refueling and maintenance outages. By identifying the possible plant conditions and cooling methods that would be used for each cooling mode, the controlling thermal-hydraulic processes and phenomena were identified. Controlling processes and phenomena include: gravity drain, core water boil-off, and reflux cooling processes. Important subcategories of the reflux cooling processes include: the initiation of reflux cooling from various plant conditions, the effects of air on reflux cooling, core level depression effects, issues regarding the steam generator secondaries, and the special case of boiler-condenser cooling with once-through steam generators. 25 refs., 6 figs., 1 tab.

  4. Arabinose-rich polymers as an evolutionary strategy to plasticize resurrection plant cell walls against desiccation.

    PubMed

    Moore, John P; Nguema-Ona, Eric E; Vicré-Gibouin, Mäite; Sørensen, Iben; Willats, William G T; Driouich, Azeddine; Farrant, Jill M

    2013-03-01

    A variety of Southern African resurrection plants were surveyed using high-throughput cell wall profiling tools. Species evaluated were the dicotyledons, Myrothamnus flabellifolia and Craterostigma plantagineum; the monocotyledons, Xerophyta viscosa, Xerophyta schlecterii, Xerophyta humilis and the resurrection grass Eragrostis nindensis, as well as a pteridophyte, the resurrection fern, Mohria caffrorum. Comparisons were made between hydrated and desiccated leaf and frond material, with respect to cell wall composition and polymer abundance, using monosaccharide composition analysis, FT-IR spectroscopy and comprehensive microarray polymer profiling in combination with multivariate data analysis. The data obtained suggest that three main functional strategies appear to have evolved to prepare plant cell walls for desiccation. Arabinan-rich pectin and arabinogalactan proteins are found in the resurrection fern M. caffrorum and the basal angiosperm M. flabellifolia where they appear to act as 'pectic plasticizers'. Dicotyledons with pectin-rich walls, such as C. plantagineum, seem to use inducible mechanisms which consist of up-regulating wall proteins and osmoprotectants. The hemicellulose-rich walls of the grass-like Xerophyta spp. and the resurrection grass E. nindensis were found to contain highly arabinosylated xylans and arabinogalactan proteins. These data support a general mechanism of 'plasticising' the cell walls of resurrection plants to desiccation and implicate arabinose-rich polymers (pectin-arabinans, arabinogalactan proteins and arabinoxylans) as the major contributors in ensuring flexibility is maintained and rehydration is facilitated in these plants. PMID:23117392

  5. Reducing residual stresses and deformations in selective laser melting through multi-level multi-scale optimization of cellular scanning strategy

    NASA Astrophysics Data System (ADS)

    Mohanty, Sankhya; Hattel, Jesper H.

    2016-04-01

    Residual stresses and deformations continue to remain one of the primary challenges towards expanding the scope of selective laser melting as an industrial scale manufacturing process. While process monitoring and feedback-based process control of the process has shown significant potential, there is still dearth of techniques to tackle the issue. Numerical modelling of selective laser melting process has thus been an active area of research in the last few years. However, large computational resource requirements have slowed the usage of these models for optimizing the process. In this paper, a calibrated, fast, multiscale thermal model coupled with a 3D finite element mechanical model is used to simulate residual stress formation and deformations during selective laser melting. The resulting reduction in thermal model computation time allows evolutionary algorithm-based optimization of the process. A multilevel optimization strategy is adopted using a customized genetic algorithm developed for optimizing cellular scanning strategy for selective laser melting, with an objective of reducing residual stresses and deformations. The resulting thermo-mechanically optimized cellular scanning strategies are compared with standard scanning strategies and have been used to manufacture standard samples.

  6. Estimation of D-Arabinose by Gas Chromatography/Mass Spectrometry as Surrogate for Mycobacterial Lipoarabinomannan in Human Urine

    PubMed Central

    De, Prithwiraj; Amin, Anita G.; Valli, Eloise; Perkins, Mark D.; McNeil, Michael; Chatterjee, Delphi

    2015-01-01

    Globally, tuberculosis is slowly declining each year and it is estimated that 37 million lives were saved between 2000 and 2013 through effective diagnosis and treatment. Currently, diagnosis relies on demonstration of the bacteria, Mycobacterium tuberculosis (Mtb), in clinical specimens by serial sputum microscopy, culture and molecular testing. Commercial immunoassay lateral flow kits developed to detect Mtb lipoglycan lipoarabinomannan (LAM) in urine as a marker of active TB exhibit poor sensitivity, especially in immunocompetent individuals, perhaps due to low abundance of the analyte. Our present study was designed to develop methods to validate the presence of LAM in a quantitative fashion in human urine samples obtained from culture-confirmed TB patients. Herein we describe, a consolidated approach for isolating LAM from the urine and quantifying D-arabinose as a proxy for LAM, using Gas Chromatography/Mass Spectrometry. 298 urine samples obtained from a repository were rigorously analyzed and shown to contain varying amounts of LAM-equivalent ranging between ~10–40 ng/mL. To further substantiate that D-arabinose detected in the samples originated from LAM, tuberculostearic acid, the unique 10-methyloctadecanoic acid present at the phosphatidylinositol end of LAM was also analyzed in a set of samples and found to be present confirming that the D-arabinose was indeed derived from LAM. Among the 144 samples from culture-negative TB suspects, 30 showed presence of D-arabinose suggesting another source of the analyte, such as disseminated TB or from non-tuberculosis mycobacterium. Our work validates that LAM is present in the urine samples of culture-positive patients in small but readily detectable amounts. The study further substantiates LAM in urine as a powerful biomarker for active tuberculosis. PMID:26633829

  7. The Cell Wall Arabinose-Deficient Arabidopsis thaliana Mutant murus5 Encodes a Defective Allele of REVERSIBLY GLYCOSYLATED POLYPEPTIDE2.

    PubMed

    Dugard, Christopher K; Mertz, Rachel A; Rayon, Catherine; Mercadante, Davide; Hart, Christopher; Benatti, Matheus R; Olek, Anna T; SanMiguel, Phillip J; Cooper, Bruce R; Reiter, Wolf-Dieter; McCann, Maureen C; Carpita, Nicholas C

    2016-07-01

    Traditional marker-based mapping and next-generation sequencing was used to determine that the Arabidopsis (Arabidopsis thaliana) low cell wall arabinose mutant murus5 (mur5) encodes a defective allele of REVERSIBLY GLYCOSYLATED POLYPEPTIDE2 (RGP2). Marker analysis of 13 F2 confirmed mutant progeny from a recombinant mapping population gave a rough map position on the upper arm of chromosome 5, and deep sequencing of DNA from these 13 lines gave five candidate genes with G→A (C→T) transitions predicted to result in amino acid changes. Of these five, only insertional mutant alleles of RGP2, a gene that encodes a UDP-arabinose mutase that interconverts UDP-arabinopyranose and UDP-arabinofuranose, exhibited the low cell wall arabinose phenotype. The identities of mur5 and two SALK insertional alleles were confirmed by allelism tests and overexpression of wild-type RGP2 complementary DNA placed under the control of the 35S promoter in the three alleles. The mur5 mutation results in the conversion of cysteine-257 to tyrosine-257 within a conserved hydrophobic cluster predicted to be distal to the active site and essential for protein stability and possible heterodimerization with other isoforms of RGP. PMID:27217494

  8. Crystal Structure of Escherichia coli L-Arabinose Isomerase (ECAI), The Putative Target of Biological Tagatose Production

    SciTech Connect

    Manjasetty,B.; Chance, M.

    2006-01-01

    Escherichia coli L-arabinose isomerase (ECAI; EC 5.3.1.4) catalyzes the isomerization of L-arabinose to L-ribulose in vivo. This enzyme is also of commercial interest as it catalyzes the conversion of D-galactose to D-tagatose in vitro. The crystal structure of ECAI was solved and refined at 2.6 Angstroms resolution. The subunit structure of ECAI is organized into three domains: an N-terminal, a central and a C-terminal domain. It forms a crystallographic trimeric architecture in the asymmetric unit. Packing within the crystal suggests the idea that ECAI can form a hexameric assembly. Previous electron microscopic and biochemical studies supports that ECAI is hexameric in solution. A comparison with other known structures reveals that ECAI adopts a protein fold most similar to E. coli fucose isomerase (ECFI) despite very low sequence identity 9.7%. The structural similarity between ECAI and ECFI with regard to number of domains, overall fold, biological assembly, and active site architecture strongly suggests that the enzymes have functional similarities. Further, the crystal structure of ECAI forms a basis for identifying molecular determinants responsible for isomerization of arabinose to ribulose in vivo and galactose to tagatose in vitro.

  9. Does polyacrylamide reduce post-fire runoff and inter-rill erosion as effectively as forest residue mulching?

    NASA Astrophysics Data System (ADS)

    Prats, Sergio; Martins, Martinho A. S.; Malvar Cortizo, Marutxa; Ben Hur, Meni; Keizer, Jan Jacob

    2013-04-01

    Forest fires are well-known to increase both overland flow and soil erosion during several years before returning to pre-fire levels. The mitigation of these effects has been less well quantified, especially by forest residue mulching and application of polyacrylamides (PAM). In this study, the effectiveness of both treatments was determined for an eucalypt stand in north-central Portugal during the first year after a wildfire. This was done using twelve micro-plots organized in four triplets located at roughly equal distances from the base to the top of a steep but short slope. After a total rainfall of 1419 mm, the overall overland flow and soil loss figures were markedly and significantly lower for the mulched than untreated plots. The PAM plots, however, did not produce significantly different runoff volumes and sediment losses than the control plots, although they revealed a tendency towards less runoff and, at the same time, greater sediment losses. Also, the key factors explaining runoff and soil erosion were basically the same for the untreated and PAM plots but distinct for the mulched plots. A possible explanation for the poor performance of the PAM was its preferential binding to the ash particles and, at the same time, the selective transport of these ash particles by the overland flow. Of interest was further that the plots on the lower section of the slope tended to produce more runoff and greater soil losses than the plots on the upper part of the slope. Possibly, this was due to differences in fire severity, which, in turn, reflected differences in biomass accumulation and, more specifically, less dry plant growth conditions.

  10. Transcriptional comparison of the filamentous fungus Neurospora crassa growing on three major monosaccharides D-glucose, D-xylose and L-arabinose

    PubMed Central

    2014-01-01

    Background D-glucose, D-xylose and L-arabinose are the three major monosaccharides in plant cell walls. Complete utilization of all three sugars is still a bottleneck for second-generation cellulolytic bioethanol production, especially for L-arabinose. However, little is known about gene expression profiles during L-arabinose utilization in fungi and a comparison of the genome-wide fungal response to these three major monosaccharides has not yet been reported. Results Using next-generation sequencing technology, we have analyzed the transcriptome of N. crassa grown on L-arabinose versus D-xylose, with D-glucose as the reference. We found that the gene expression profiles on L-arabinose were dramatically different from those on D-xylose. It appears that L-arabinose can rewire the fungal cell metabolic pathway widely and provoke the expression of many kinds of sugar transporters, hemicellulase genes and transcription factors. In contrast, many fewer genes, mainly related to the pentose metabolic pathway, were upregulated on D-xylose. The rewired metabolic response to L-arabinose was significantly different and wider than that under no carbon conditions, although the carbon starvation response was initiated on L-arabinose. Three novel sugar transporters were identified and characterized for their substrates here, including one glucose transporter GLT-1 (NCU01633) and two novel pentose transporters, XAT-1 (NCU01132), XYT-1 (NCU05627). One transcription factor associated with the regulation of hemicellulase genes, HCR-1 (NCU05064) was also characterized in the present study. Conclusions We conducted the first transcriptome analysis of Neurospora crassa grown on L-arabinose and performed a comparative analysis with cells grown on D-xylose and D-glucose, which deepens the understanding of the utilization of L-arabinose and D-xylose in filamentous fungi. The dataset generated by this research will be useful for mining target genes for D-xylose and L-arabinose utilization

  11. Does further clean-up reduce the matrix enhancement effect in gas chromatographic analysis of pesticide residues in food?

    PubMed

    Schenck, F J; Lehotay, S J

    2000-01-28

    Sample extracts of apples, peas, green beans, oranges, raspberries, clementines, carrots, and wheat obtained using the Food and Drug Administration (acetone extraction) and Canadian Pest Management Regulatory Agency (acetonitrile extraction) multiresidue methods for pesticides were subjected to clean-up using different solid-phase extraction (SPE) cartridges in an attempt to reduce or eliminate the matrix enhancement effect. The matrix enhancement effect is related to the blocking of active sites on the injector liner by matrix components, thereby increasing signal in the presence of matrix versus standards in solvent in which the pesticides themselves interact with the active sites. Graphitized carbon black (GCB) was often used in combination with various anion-exchange SPE cartridges. The extracts were then spiked with organophosphorus insecticides. These process standards were then compared to standards in acetone of the same concentration using gas chromatography with flame photometric detection or ion trap mass spectrometric detection. Sample matrix enhancement varied from little to no effect for some pesticides (e.g. chlorpyrifos, malathion) to >200% in the case of certain susceptible pesticides. The GCB removed color components but showed little effect in reducing matrix enhancement by itself. The anion-exchange cartridges in combination with GCB or not, substantially reduced the matrix enhancement effect but did not eliminate it. PMID:10677079

  12. LEDGIN-mediated Inhibition of Integrase-LEDGF/p75 Interaction Reduces Reactivation of Residual Latent HIV.

    PubMed

    Vranckx, Lenard S; Demeulemeester, Jonas; Saleh, Suha; Boll, Annegret; Vansant, Gerlinde; Schrijvers, Rik; Weydert, Caroline; Battivelli, Emilie; Verdin, Eric; Cereseto, Anna; Christ, Frauke; Gijsbers, Rik; Debyser, Zeger

    2016-06-01

    Persistence of latent, replication-competent Human Immunodeficiency Virus type 1 (HIV-1) provirus is the main impediment towards a cure for HIV/AIDS (Acquired Immune Deficiency Syndrome). Therefore, different therapeutic strategies to eliminate the viral reservoirs are currently being explored. We here propose a novel strategy to reduce the replicating HIV reservoir during primary HIV infection by means of drug-induced retargeting of HIV integration. A novel class of integration inhibitors, referred to as LEDGINs, inhibit the interaction between HIV integrase and the LEDGF/p75 host cofactor, the main determinant of lentiviral integration site selection. We show for the first time that LEDGF/p75 depletion hampers HIV-1 reactivation in cell culture. Next we demonstrate that LEDGINs relocate and retarget HIV integration resulting in a HIV reservoir that is refractory to reactivation by different latency-reversing agents. Taken together, these results support the potential of integrase inhibitors that modulate integration site targeting to reduce the likeliness of viral rebound. PMID:27428435

  13. Quantification of glucose, xylose, arabinose, furfural, and HMF in corncob hydrolysate by HPLC-PDA-ELSD.

    PubMed

    Liu, Xuejun; Ai, Ning; Zhang, Haiyan; Lu, Meizhen; Ji, Dengxiang; Yu, Fengwen; Ji, Jianbing

    2012-05-15

    Lignocellulose and other carbohydrates are being studied extensively as potential renewable carbon sources for liquid biofuels and other valuable chemicals. In the present study, a simple, sensitive, selective, and reliable HPLC method using a photodiode array (PDA) detector and an evaporative light scattering detector (ELSD) was developed for the simultaneous determination of important sugars (D(+)-cellobiose, glucose, xylose, and arabinose), furfural and 5-hydroxymethylfurfural (5-HMF) in lignocellulose hydrolysate. The analysis was carried out on an Aminex HPX-87H column (250 mm × 4.6 mm, 5 μm particle size). Ultra-pure water with 0.00035 M H(2)SO(4) was used as the mobile phase with a flow rate of 0.6 mL/min. The temperature of the ELSD drift tube was kept at 50 °C, the carrier gas pressure was 350 kPa, and the gain was set at 7. Furfural and 5-HMF were quantified on a PDA detector at 275 nm and 284 nm, respectively. The sugar concentrations were determined by ELSD. This method was validated for accuracy and precision. The regression equation revealed a good linear relationship (r(2) = 0.9986 ± 0.0012) within the test ranges. The method showed good reproducibility for the quantification of six analytes in corncob hydrolysate, with intra- and inter-day variations less than 1.12%. This method is also convenient because it allows the rapid analysis of the primary products of biomass hydrolysis and carbohydrate degradation. PMID:22516168

  14. Overexpression of hydroxynitrile lyase in cassava roots elevates protein and free amino acids while reducing residual cyanogen levels.

    PubMed

    Narayanan, Narayanan N; Ihemere, Uzoma; Ellery, Claire; Sayre, Richard T

    2011-01-01

    Cassava is the major source of calories for more than 250 million Sub-Saharan Africans, however, it has the lowest protein-to-energy ratio of any major staple food crop in the world. A cassava-based diet provides less than 30% of the minimum daily requirement for protein. Moreover, both leaves and roots contain potentially toxic levels of cyanogenic glucosides. The major cyanogen in cassava is linamarin which is stored in the vacuole. Upon tissue disruption linamarin is deglycosylated by the apolplastic enzyme, linamarase, producing acetone cyanohydrin. Acetone cyanohydrin can spontaneously decompose at pHs >5.0 or temperatures >35°C, or is enzymatically broken down by hydroxynitrile lyase (HNL) to produce acetone and free cyanide which is then volatilized. Unlike leaves, cassava roots have little HNL activity. The lack of HNL activity in roots is associated with the accumulation of potentially toxic levels of acetone cyanohydrin in poorly processed roots. We hypothesized that the over-expression of HNL in cassava roots under the control of a root-specific, patatin promoter would not only accelerate cyanogenesis during food processing, resulting in a safer food product, but lead to increased root protein levels since HNL is sequestered in the cell wall. Transgenic lines expressing a patatin-driven HNL gene construct exhibited a 2-20 fold increase in relative HNL mRNA levels in roots when compared with wild type resulting in a threefold increase in total root protein in 7 month old plants. After food processing, HNL overexpressing lines had substantially reduced acetone cyanohydrin and cyanide levels in roots relative to wild-type roots. Furthermore, steady state linamarin levels in intact tissues were reduced by 80% in transgenic cassava roots. These results suggest that enhanced linamarin metabolism contributed to the elevated root protein levels. PMID:21799761

  15. Assessment of some straw-derived materials for reducing the leaching potential of Metribuzin residues in the soil

    NASA Astrophysics Data System (ADS)

    Cara, Irina Gabriela; Trincă, Lucia Carmen; Trofin, Alina Elena; Cazacu, Ana; Ţopa, Denis; Peptu, Cătălina Anişoara; Jităreanu, Gerard

    2015-12-01

    Biomass (straw waste) can be used as raw to obtain materials for herbicide removal from wastewater. These by-products have some important advantages, being environmentally friendly, easily available, presenting low costs, and requiring little processing to increase their adsorptive capacity. In the present study, some materials derived from agricultural waste (wheat, corn and soybean straw) were investigated as potential adsorbents for metribuzin removal from aqueous solutions. The straw wastes were processed by grinding, mineralisation (850 °C) and KOH activation in order to improve their functional surface activity. The materials surface characteristics were investigated by scanning electron microscopy, energy dispersive X-ray spectroscopy and atomic force microscopy. The adsorbents capacity was evaluated using batch sorption tests and liquid chromatography coupled with mass spectrometry for herbicide determination. For adsorption isotherms, the equilibrium time considered was 3 h. The experimental adsorption data were modelled by Freundlich and Langmuir models. The activated straw and ash-derived materials from wheat, corn and soybean increased the adsorption capacity of metribuzin with an asymmetrical behaviour. Overall, our results sustain that activated ash-derived from straw and activated straw materials can be a valuable solution for reducing the leaching potential of metribuzin through soil.

  16. Structural characterization of (1→2)-β-xylose-(1→3)-α-arabinose-containing oligosaccharide products of extracted switchgrass (Panicum virgatum, L.) xylan after exhaustive enzymatic treatment with α-arabinofuranosidase and β-endo-xylanase.

    PubMed

    Bowman, Michael J; Dien, Bruce S; Vermillion, Karl E; Mertens, Jeffrey A

    2014-10-29

    Switchgrass (Panicum virgatum, L.) is a potential dedicated biomass crop for use in biocatalytic conversion systems to biofuels. Nearly 30% of switchgrass cell wall material is xylan. The complete depolymerization of xylan is desirable both as an additional carbon source for microbial fermentation and to reduce inhibitory effects xylooligomers may have on cellulolytic glycoside hydrolase enzymes. To identify structural features of switchgrass xylan that are not distinguishable by mass spectrometry alone, a α-arabinofuranosidase enzyme was used to remove the arabinose side chains from alkali-extracted switchgrass xylan from three cultivars with simultaneous hydrolysis by β-endo-xylanase to enrich for oligosaccharide products with extended branching. The two most abundant enzymatic digestion products were separated and characterized by LC-MS(n), linkage analysis, and NMR. These two oligosaccharides were present in all three switchgrass cultivars and found to contain (1→2)-β-xylose-(1→3)-α-arabinose side chains, a linkage not previously reported in switchgrass. PMID:25240184

  17. Web-based Mindfulness-based Cognitive Therapy for reducing residual depressive symptoms: An open trial and quasi-experimental comparison to propensity score matched controls.

    PubMed

    Dimidjian, Sona; Beck, Arne; Felder, Jennifer N; Boggs, Jennifer M; Gallop, Robert; Segal, Zindel V

    2014-09-18

    Mindfulness-based Cognitive Therapy (MBCT) has been shown to effectively prevent relapse and reduce residual depressive symptoms (RDS), yet it faces barriers to dissemination. The present study examined Mindful Mood Balance (MMB), the first web-based approach to deliver the core content of MBCT. Of the 107 recurrently depressed individuals screened, 100 elected to enroll in the study and received MMB in an 8-session open trial with 6-month follow-up. Outcomes included depressive symptom severity, rumination and mindful awareness, and program engagement. A quasi-experimental comparison between MMB participants and propensity matched case-controls receiving usual depression care (UDC) (N = 100) also was conducted. The full sample and the subgroup with residual depressive symptoms (N = 42) showed significantly reduced depressive severity, which was sustained over six months, and improvement on rumination and mindfulness. Examination of acceptability of MMB indicated that 42% of participants within the full sample and 36% of the RDS subgroup completed all 8 sessions and 53% within the full sample and 50% within the RDS subgroup completed at least 4 sessions, and that participants engaged with daily mindfulness practice. MMB also was associated with significant reduction in RDS severity as compared to quasi-experimental propensity matched controls. Although the use of a non-randomized design, with potential unmeasured differences between groups, and short interval of clinical follow-up were limitations, findings from this study support the web-based delivery of MBCT and suggest clinical benefits for participants with histories of depression and with RDS, relative to those receiving usual care alone. PMID:25461782

  18. X-ray structures of Bacillus pallidus d-arabinose isomerase and its complex with l-fucitol.

    PubMed

    Takeda, Kosei; Yoshida, Hiromi; Izumori, Ken; Kamitori, Shigehiro

    2010-06-01

    d-Arabinose isomerase (d-AI), also known as l-fucose isomerase (l-FI), catalyzes the aldose-ketose isomerization of d-arabinose to d-ribulose, and l-fucose to l-fuculose. Bacillus pallidus (B. pallidus) d-AI can catalyze isomerization of d-altrose to d-psicose, as well as d-arabinose and l-fucose. Three X-ray structures of B. pallidus d-AI in complexes with 2-methyl-2,4-pentadiol, glycerol and an inhibitor, l-fucitol, were determined at resolutions of 1.77, 1.60 and 2.60 A, respectively. B. pallidus d-AI forms a homo-hexamer, and one subunit has three domains of almost equal size; two Rossmann fold domains and a mimic of the (beta/alpha) barrel fold domain. A catalytic metal ion (Mn(2+)) was found in the active site coordinated by Glu342, Asp366 and His532, and an additional metal ion was found at the channel for the passage of a substrate coordinated by Asp453. The X-ray structures basically supported the ene-diol mechanism for the aldose-ketose isomerization by B. pallidus d-AI, as well as Escherichia coli (E. coli) l-FI, in which Glu342 and Asp366 facing each other at the catalytic metal ion transfer a proton from C2 to C1 and O1 to O2, acting as acid/base catalysts, respectively. However, considering the ionized state of Asp366, the catalytic reaction also possibly occurs through the negatively charged ene-diolate intermediate stabilized by the catalytic metal ion. A structural comparison with E. colil-FI showed that B. pallidus d-AI possibly interconverts between "open" and "closed" forms, and that the additional metal ion found in B. pallidus d-AI may help to stabilize the channel region. PMID:20123133

  19. Novel transporters from Kluyveromyces marxianus and Pichia guilliermondii expressed in Saccharomyces cerevisiae enable growth on L-arabinose and D-xylose.

    PubMed

    Knoshaug, Eric P; Vidgren, Virve; Magalhães, Frederico; Jarvis, Eric E; Franden, Mary Ann; Zhang, Min; Singh, Arjun

    2015-10-01

    Genes encoding L-arabinose transporters in Kluyveromyces marxianus and Pichia guilliermondii were identified by functional complementation of Saccharomyces cerevisiae whose growth on L-arabinose was dependent on a functioning L-arabinose transporter, or by screening a differential display library, respectively. These transporters also transport D-xylose and were designated KmAXT1 (arabinose-xylose transporter) and PgAXT1, respectively. Transport assays using L-arabinose showed that KmAxt1p has K(m) 263 mM and V(max) 57 nM/mg/min, and PgAxt1p has K(m) 0.13 mM and V(max) 18 nM/mg/min. Glucose, galactose and xylose significantly inhibit L-arabinose transport by both transporters. Transport assays using D-xylose showed that KmAxt1p has K(m) 27 mM and V(max) 3.8 nM/mg/min, and PgAxt1p has K(m) 65 mM and V(max) 8.7 nM/mg/min. Neither transporter is capable of recovering growth on glucose or galactose in a S. cerevisiae strain deleted for hexose and galactose transporters. Transport kinetics of S. cerevisiae Gal2p showed K(m) 371 mM and V(max) 341 nM/mg/min for L-arabinose, and K(m) 25 mM and V(max) 76 nM/mg/min for galactose. Due to the ability of Gal2p and these two newly characterized transporters to transport both L-arabinose and D-xylose, one scenario for the complete usage of biomass-derived pentose sugars would require only the low-affinity, high-throughput transporter Gal2p and one additional high-affinity general pentose transporter, rather than dedicated D-xylose or L-arabinose transporters. Additionally, alignment of these transporters with other characterized pentose transporters provides potential targets for substrate recognition engineering. PMID:26129747

  20. Reduced susceptibility to all neuraminidase inhibitors of influenza H1N1 viruses with haemagglutinin mutations and mutations in non-conserved residues of the neuraminidase

    PubMed Central

    McKimm-Breschkin, Jennifer L.; Williams, Janelle; Barrett, Susan; Jachno, Kim; McDonald, Mandy; Mohr, Peter G.; Saito, Takehiko; Tashiro, Masato

    2013-01-01

    Objectives We characterized human H1N1 influenza isolate A/Hokkaido/15/02, which has haemagglutinin and neuraminidase mutations that reduce drug susceptibility to oseltamivir, zanamivir and peramivir. Methods One wild-type and three mutant viruses were isolated by plaque purification. Viruses were tested in MUNANA-based enzyme assays, cell culture and receptor binding assays. Results Two viruses had a neuraminidase Y155H mutation that reduced susceptibility in the enzyme inhibition assay to all inhibitors by 30-fold to >100-fold. The Y155H mutation reduced plaque size and affected the stability, Km and pH activity profile of the enzyme. In contrast to previous mutants, this neuraminidase demonstrated a slower rate of inhibitor binding in the IC50 kinetics assay. One virus had both the Y155H mutation and a haemagglutinin D225G mutation that rescued the small-plaque phenotype of the Y155H virus and affected receptor binding and drug susceptibility in cell culture and binding assays. We also isolated a third mutant virus, with both neuraminidase V114I and haemagglutinin D225N mutations, which affected susceptibility in the enzyme inhibition assay and receptor binding, respectively, but to lesser extents than the Y155H and D225G mutations. Conclusions Neither Y155 nor V114 is conserved across neuraminidase subtypes. Furthermore, Y155 is not conserved even among avian and swine N1 viruses. Structurally, both residues reside far from the neuraminidase active site. D225 forms part of the receptor binding site of the haemagglutinin. We believe this is the first demonstration of a specific haemagglutinin mutation correlating with reduced drug susceptibility in plaque assays in both Madin Darby Canine Kidney and SIAT cells. PMID:23759505

  1. Production of the amino acids l-glutamate, l-lysine, l-ornithine and l-arginine from arabinose by recombinant Corynebacterium glutamicum.

    PubMed

    Schneider, Jens; Niermann, Karin; Wendisch, Volker F

    2011-07-10

    Amino acid production processes with Corynebacterium glutamicum are based on media containing glucose from starch hydrolysis or fructose and sucrose as present in molasses. Simultaneous utilization of various carbon sources, including glucose, fructose and sucrose, in blends is a typical characteristic of this bacterium. The renewable non-food carbon source arabinose, which is present in hemicellulosic hydrolysates, cannot be utilized by most C. glutamicum strains. Heterologous expression of the araBAD operon from Escherichia coli in the wild-type and in an l-lysine producing strain of C. glutamicum was shown to enable production of l-glutamate and l-lysine, respectively, from arabinose as sole carbon source. l-Ornithine and l-arginine producing strains were constructed and shown to produce l-ornithine and l-arginine from arabinose when araBAD from E. coli was expressed. Moreover, the recombinant strains produced l-glutamate, l-lysine, l-ornithine and l-arginine respectively, from arabinose also when glucose-arabinose blends were used as carbon sources. PMID:20638422

  2. Metabolite gene regulation: imidazole and imidazole derivatives which circumvent cyclic adenosine 3',5'-monophosphate in induction of the Escherichia coli L-arabinose operon.

    PubMed Central

    Kline, E L; Bankaitis, V A; Brown, C S; Montefiori, D C

    1980-01-01

    Imidazole, histidine, histamine, histidinol phosphate, urocanic acid, or imidazolepropionic acid were shown to induce the L-arabinose operon in the absence of cyclic adenosine 3',5'-monophosphate. Induction was quantitated by measuring the increased differential rate of synthesis of L-arabinose isomerase in Escherichia coli strains which carried a deletion of the adenyl cyclase gene. The crp gene product (cyclic adenosine 3',5'-monophosphate receptor protein) and the araC gene product (P2) were essential for induction of the L-arabinose operon by imidazole and its derivatives. These compounds were unable to circumvent the cyclic adenosine 3',5'-monophosphate in the induction of the lactose or the maltose operons. The L-arabinose regulon was catabolite repressed upon the addition of glucose to a strain carrying an adenyl cyclase deletion growing in the presence of L-arabinose with imidazole. These results demonstrated that several imidazole derivatives may be involved in metabolite gene regulation (23). Images PMID:6245056

  3. The residual and direct effects of reduced-risk and conventional miticides on twospotted spider mites, Tetranychus urticae (Acari: Tetranychidae) and predatory mites (Acari: Phytoseiidae)

    SciTech Connect

    Liburd, O.E.; White, J.C.; Rhodes, E.M.; Browdy, A.A.

    2007-03-15

    The residual effects of several reduced-risk and conventional miticides were evaluated in strawberries (Fragaria z ananassa Duchesne) on the twospotted spider mite (TSSM), Tetranychus urticae Koch (Acari: Tetranychidae) and on 2 predatory mites, Neoseiulus californicus McGregor and Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae). Experiments were conducted in the laboratory and greenhouse. The greenhouse experiments also tested the direct effects of the miticides on TSSM. The efficacy of conventional and reduced-risk miticides was evaluated on strawberry leaf discs and on whole plants for control of TSSM. Furthermore, the residual effects of these miticides were evaluated on whole strawberry plants against selective predatory mites. For TSSM, 5 treatments were evaluated: a conventional miticide; fenbutatin-oxide (Vendex[reg]) and 3 reduced-risk miticides; binfenazate (Acramite 50WP[reg]), activated garlic extract (Repel[reg]), sesame seed and castor oil (Wipeout[reg]), and a water-treated control. For predatory mites, the residual effects of only Acramite[reg] and Vendex[reg] were evaluated. Acramite[reg] was the most effective acaricide in reducing TSSM populations in both the laboratory and greenhouse experiments. Vendex[reg] and Wipeout[reg] were also effective in the laboratory, but did not cause significant reduction of TSSM in the greenhouse. Repel[reg] was the least effective of the 4 pesticides evaluated. Neither Acramite[reg] nor Vendex[reg] had a significant effect on either predatory mite species. However, there appeared to be more predatory mites on the Vendex[reg]-treated plants than on the Acramite[reg]-treated plants. There were significantly more predatory mites of both species on the cue plants, which were inoculated with TSSM versus the non-cue plants, which were not inoculated. (author) [Spanish] Los efectos residuales en poblaciones de la 'arana roja', Tetranychus urticae Koch (Acari: Tetranichidae) y de los acaros predadores

  4. An encodable lanthanide binding tag with reduced size and flexibility for measuring residual dipolar couplings and pseudocontact shifts in large proteins.

    PubMed

    Barb, Adam W; Subedi, Ganesh P

    2016-01-01

    Metal ions serve important roles in structural biology applications from long-range perturbations seen in magnetic resonance experiments to electron-dense signatures in X-ray crystallography data; however, the metal ion must be secured in a molecular framework to achieve the maximum benefit. Polypeptide-based lanthanide-binding tags (LBTs) represent one option that can be directly encoded within a recombinant protein expression construct. However, LBTs often exhibit significant mobility relative to the target molecule. Here we report the characterization of improved LBTs sequences for insertion into a protein loop. These LBTs were inserted to connect two parallel alpha helices of an immunoglobulin G (IgG)-binding Z domain platform. Variants A and B bound Tb(3+) with high affinity (0.70 and 0.13 μM, respectively) and displayed restricted LBT motion. Compared to the parent construct, the metal-bound A experienced a 2.5-fold reduction in tag motion as measured by magnetic field-induced residual dipolar couplings and was further studied in a 72.2 kDa complex with the human IgG1 fragment crystallizable (IgG1 Fc) glycoprotein. The appearance of both pseudo-contact shifts (-0.221 to 0.081 ppm) and residual dipolar couplings (-7.6 to 14.3 Hz) of IgG1 Fc resonances in the IgG1 Fc:(variant A:Tb(3+))2 complex indicated structural restriction of the LBT with respect to the Fc. These studies highlight the applicability of improved LBT sequences with reduced mobility to probe the structure of macromolecular systems. PMID:26728077

  5. Product PCNPsurv or the "reduced" evaporation residue cross section σER/σfusion for "hot" fusion reactions studied with the dynamical cluster-decay model

    NASA Astrophysics Data System (ADS)

    Chopra, Sahila; Kaur, Arshdeep; Hemdeep, Gupta, Raj K.

    2016-04-01

    The product PCNPsurv of compound nucleus (CN) fusion probability PCN and survival probability Psurv is calculated to determine the reduced evaporation residue cross section σER/σfusion , denoted σERreduced, with (total) fusion cross section σfusion given as a sum of CN-formation cross section σCN and non-CN cross section σnCN for each reaction, where σCN is the sum of evaporation residue cross section σER and fusion-fission cross section σff and σnCN, if not measured, is estimated empirically as the difference between measured and calculated σfusion. Our calculations of PCN and Psurv, based on the dynamical cluster-decay model, were successfully made for some 17 "hot" fusion reactions, forming different CN of mass numbers ACN˜100 -300 , with deformations of nuclei up to hexadecapole deformations and "compact" orientations for both coplanar (Φc=0∘ ) and noncoplanar (Φc≠0∘ ) configurations, using various different nuclear interaction potentials. Interesting variations of σERreduced with CN excitation energy E*, fissility parameter χ , CN mass ACN, and Coulomb parameter Z1Z2 show that, independent of entrance channel, different isotopes of CN, and nuclear interaction potentials used, the dominant quantity in the product is Psurv, which classifies all the studied CN into three groups of weakly fissioning, radioactive, and strongly fissioning superheavy nuclei, with relative magnitudes of σERreduced˜1 , ˜10-6 , and ˜10-11 , which, like for PCN, get further grouped in two dependencies of (i) weakly fissioning and strongly fissioning superheavy nuclei decreasing with increasing E* and (ii) radioactive nuclei increasing with increasing E*.

  6. Antihyperlipidemic and hepatoprotective activities of residue polysaccharide from Cordyceps militaris SU-12.

    PubMed

    Wang, Liqin; Xu, Nuo; Zhang, Jianjun; Zhao, Huajie; Lin, Lin; Jia, Shouhua; Jia, Le

    2015-10-20

    Cordyceps militaris has been artificially cultivated in China, and the great amounts of produced medium residue were discarded after the harvest. The aims of this work were to analyze the structure of the residue polysaccharide (RPS) of C. militaris SU-12, and to investigate the pharmacological effects of RPS on lipid metabolism and oxidative stress. RPS was composed of glucose, arabinose and mannose with a ratio of 62:1.6:1 by gas chromatography analysis, and the Mw (weight-average molecular weight), Mn (number-average molecular weight) and Mz (z-average molecular weight) of RPS were 2.86×10(3), 6.85×10(2), and 1.97×10(4)Da, respectively. The mice experiments demonstrated that RPS could reduce the levels of blood and liver lipid, and improve the glutamate pyruvate transaminase and antioxidant activity. The histopathological observations of mice livers indicated that RPS could attenuate liver cell injury. Results suggest that the RPS might be used as a potential antihyperlipidemic, hepatoprotective and antioxidant product. PMID:26256194

  7. Lipid production through simultaneous utilization of glucose, xylose, and L-arabinose by Pseudozyma hubeiensis: a comparative screening study.

    PubMed

    Tanimura, Ayumi; Takashima, Masako; Sugita, Takashi; Endoh, Rikiya; Ohkuma, Moriya; Kishino, Shigenobu; Ogawa, Jun; Shima, Jun

    2016-12-01

    Co-fermentation of glucose, xylose and L-arabinose from lignocellulosic biomass by an oleaginous yeast is anticipated as a method for biodiesel production. However, most yeasts ferment glucose first before consuming pentoses, due to glucose repression. This preferential utilization results in delayed fermentation time and lower productivity. Therefore, co-fermentation of lignocellulosic sugars could achieve cost-effective conversion of lignocellulosic biomass to microbial lipid. Comprehensive screening of oleaginous yeasts capable of simultaneously utilizing glucose, xylose, and L-arabinose was performed by measuring the concentration of sugars remaining in the medium and of lipids accumulated in the cells. We found that of 1189 strains tested, 12 had the ability to co-ferment the sugars. The basidiomycete yeast Pseudozyma hubeiensis IPM1-10, which had the highest sugars consumption rate of 94.1 %, was selected by culturing in a batch culture with the mixed-sugar medium. The strain showed (1) simultaneous utilization of all three sugars, and (2) high lipid-accumulating ability. This study suggests that P. hubeiensis IPM1-10 is a promising candidate for second-generation biodiesel production from hydrolysate of lignocellulosic biomass. PMID:27566647

  8. Mutagenicity study on pyrazole, seven pyrazole derivatives, and two nitroimidazoles with the L-arabinose resistance test of Salmonella typhimurium

    SciTech Connect

    Alejandre-Duran, E.; Ruiz-Rubio, M.; Claramunt, R.M.; Lopez, C.; Pueyo, C.

    1986-01-01

    The mutagenicity of pyrazole and seven pyrazole derivatives (4-nitropyrazole, 4-bromopyrazole, 1-methyl-4-nitropyrazole, 3,5-dimethyl-4-nitropyrazole, 1-methyl-4-bromopyrazole, 4,4'-dinitro-1, 1'-methylene-dipyrazole and 4,4'-dibromo-1,1'-methylene-dipyrazole) has been investigated with the L-arabinose forward mutation assay of Salmonella typhimurium. Two nitroimidazoles (1-methyl-5-nitroimidazole and metronidazole) were included as reference drugs. The mutagenicity of each chemical was determined by both preincubation and liquid tests, in the presence or absence of S9 microsomal fraction. The mutagenic responses was expressed as the absolute number of L-arabinose resistant mutants growing in selective plates, supplemented with traces of D-glucose. Strain BA13 with a wild-type lipopolysaccharide barrier was used as a comparison to the deep rough derivative BA9. No mutagenic effect was detected with pyrazole and two of its derivatives, 1-methyl-4-bromopyrazole and 4,4'-dibromo-1,1'-methylene-dipyrazole. The other five pyrazole derivatives were mutagenic to different degrees, although their mutagenic potencies were always considerably lower than those of the two nitroimidazoles. The results suggest that 4-nitropyrazoles, as well as 4,4'-dinitro-1, 1'-methylene-dipyrazoles, should be investigated further as alternatives to, or even substitutes for, the currently used nitroimidazoles.

  9. The glcB locus of Rhizobium leguminosarum VF39 encodes an arabinose-inducible malate synthase.

    PubMed

    García-de los Santos, Alejandro; Morales, Alejandro; Baldomá, Laura; Clark, Scott R D; Brom, Susana; Yost, Christopher K; Hernández-Lucas, Ismael; Aguilar, Juan; Hynes, Michael F

    2002-10-01

    In the course of a study conducted to isolate genes upregulated by plant cell wall sugars, we identified an arabinose-inducible locus from a transcriptional fusion library of Rhizobium leguminosarum VF39, carrying random insertions of the lacZ transposon Tn5B22. Sequence analysis of the locus disrupted by the transposon revealed a high similarity to uncharacterized malate synthase G genes from Sinorhizobium meliloti, Agrobacterium tumefaciens, and Mesorhizobium loti. This enzyme catalyzes the condensation of glyoxylate and acetyl-CoA to yield malate and CoA and is thought to be a component of the glyoxylate cycle, which allows microorganisms to grow on two carbon compounds. Enzyme assays showed that a functional malate synthase is encoded in the glcB gene of R. leguminosarum and that its expression is induced by arabinose, glycolate, and glyoxylate. An Escherichia coli aceB glcB mutant, complemented with the R. leguminosarum PCR-amplified gene, recovered malate synthase activity. A very similar genome organization of the loci containing malate synthase and flanking genes was observed in R. leguminosarum, S. meliloti, and A. tumefaciens. Pea plants inoculated with the glcB mutant or the wild-type strain showed no significant differences in nitrogen fixation. This is the first report regarding the characterization of a mutant in one of the glyoxylate cycle enzymes in the rhizobia. PMID:12489782

  10. L-Arabinose (pyranose and furanose rings)-branched poly (vinylalcohol): enzymatic synthesis of the sugar esters followed by free radical polymerization.

    PubMed

    Rodrigues Borges, Maurício; Balaban, Rosangela de Carvalho

    2014-12-20

    Herein this study reports the successful synthesis of a new poly(vinyl alcohol) (PVA), containing L-arabinose (L-arabinopyranose and arabinofuranose isomers) branched in only two steps: (1) production of polymerizable monomers of L-arabinose isomers (pyranose and furanose forms) through enzymatic synthesis using alkaline protease from Bacillus subtilis as catalyst and two substrates: L-arabinose and Divinyl Adipate (DVA) in N,N-dimethylformamide (DMF); (2) radical polymerization of the monomers, using an initiator system consisting of potassium persulfate and hydrogen peroxide in water. The transesterification of DVA with L-arabinose was monitored via qualitative analysis by TLC, confirming the formation of the vinyl sugar ester. The acylation occurred on the two different cyclic conformations of the L-arabinose which coexist in equilibrium: (α/β) arabinofuranose and (α/β) arabinopyranose. The acylation positions and the chemical structure of the 5-O-vinyl adipoyl L-arabinofuranose and 4-O-vinyl adipolyl L-arabinopyranose formed were determined by 13C NMR. The surface activity of the L-arabinose esters mixture (monomers) was compared with a commercial product based on phenol formaldehyde polyoxyalkylene polyamine, largely used as surfactant in many industries. FTIR spectroscopy of the sugar ester monomers and the respective polymer were compared revealing the disappearance of the vinyl group in the polymer spectrum. The polymer number-average molar mass (Mn) and the weight-average molar mass (Mw) were determined by gel permeation chromatography (GPC) presenting the following results: 2.9 × 10(4) Da and 7.2 × 10(4) Da, respectively, and polydispersity (Mw/Mn) equal to 2.48. PMID:25450639

  11. Immobilization of β-glucosidase from Aspergillus niger on κ-carrageenan hybrid matrix and its application on the production of reducing sugar from macroalgae cellulosic residue.

    PubMed

    Tan, Inn Shi; Lee, Keat Teong

    2015-05-01

    A novel concept for the synthesis of a stable polymer hybrid matrix bead was developed in this study. The beads were further applied for enzyme immobilization to produce stable and active biocatalysts with low enzyme leakage, and high immobilization efficiency, enzyme activity, and recyclability. The immobilization conditions, including PEI concentration, activation time and pH of the PEI solution were investigated and optimized. All formulated beads were characterized for its functionalized groups, composition, surface morphology and thermal stability. Compared with the free β-glucosidase, the immobilized β-glucosidase on the hybrid matrix bead was able to tolerate broader range of pH values and higher reaction temperature up to 60 °C. The immobilized β-glucosidase was then used to hydrolyse pretreated macroalgae cellulosic residue (MCR) for the production of reducing sugar and a hydrolysis yield of 73.4% was obtained. After repeated twelve runs, immobilized β-glucosidase retained about 75% of its initial activity. PMID:25465785

  12. Copper-dependent inhibition of cytochrome c oxidase by Abeta(1-42) requires reduced methionine at residue 35 of the Abeta peptide.

    PubMed

    Crouch, Peter J; Barnham, Kevin J; Duce, James A; Blake, Rachel E; Masters, Colin L; Trounce, Ian A

    2006-10-01

    By altering key amino acid residues of the Alzheimer's disease-associated amyloid-beta peptide, we investigated the mechanism through which amyloid-beta inhibits cytochrome c oxidase (EC 1.9.3.1). Native amyloid-beta inhibited cytochrome oxidase by up to 65%, and the level of inhibition was determined by the period of amyloid-beta ageing before the cytochrome oxidase assay. Substituting tyrosine-10 with alanine did not affect maximal enzyme inhibition, but the altered peptide required a longer period of ageing. By contrast, oxidizing the sulfur of methionine-35 to a sulfoxide, or substituting methionine-35 with valine, completely abrogated the peptide's inhibitory potential towards cytochrome oxidase. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed that the loss of inhibitory potential towards cytochrome oxidase with the methionine-35-altered peptides did not correlate with a substantially different distribution of amyloid-beta oligomeric species. Although the amyloid-beta-mediated inhibition of cytochrome oxidase was completely dependent on the presence of divalent Cu2+, it was not supported by monovalent Cu+, and experiments with catalase and H2O2 indicated that the mechanism of cytochrome oxidase inhibition does not involve amyloid-beta-mediated H2O2 production. We propose that amyloid-beta-mediated inhibition of cytochrome oxidase is dependent on the peptide's capacity to bind, then reduce Cu2+, and that it may involve the formation of a redox active amyloid-beta-methionine radical. PMID:16987248

  13. Effects of ad libitum and restricted feeding on early production performance and body composition of Yorkshire pigs selected for reduced residual feed intake.

    PubMed

    Boddicker, N; Gabler, N K; Spurlock, M E; Nettleton, D; Dekkers, J C M

    2011-08-01

    Residual feed intake (RFI), defined as the difference between observed and expected feed intake based on growth and backfat, has been used to investigate genetic variation in feed efficiency in cattle, poultry and pigs. However, little is known about the biological basis of differences in RFI in pigs. To this end, the objective of this study was to evaluate the fifth generation of a line of pigs selected for reduced RFI against a randomly selected Control line for performance, carcass and chemical carcass composition and overall efficiency. Here, emphasis was on the early grower phase. A total of 100 barrows, 50 from each line, were paired by age and weight (22.6 ± 3.9 kg) and randomly assigned to one of four feeding treatments in 11 replicates: ad libitum (Ad), 75% of Ad (Ad75), 55% of Ad (Ad55) and weight stasis (WS), which involved weekly adjustments in intake to keep body weight (BW) constant for each pig. Pigs were individually penned (group housing was used for selection) and were on treatment for 6 weeks. Initial BW did not significantly differ between the lines (P > 0.17). Under Ad feeding, the low RFI pigs consumed 8% less feed compared with Control line pigs (P < 0.06), had less carcass fat (P < 0.05), but with no significant difference in growth rate (P > 0.85). Under restricted feeding, low RFI pigs under the Ad75 treatment had a greater rate of gain while consuming the same amount of feed as Control pigs. Despite the greater gain, no significant line differences in carcass composition or carcass traits were observed. For the WS treatment, low RFI pigs had similar BW (P > 0.37) with no significant difference in feed consumption (P > 0.32). Overall, selection for reduced RFI has decreased feed intake, with limited differences in growth rate but reduced carcass fat, as seen under Ad feeding. Collectively, results indicate that the effects of selection for low RFI are evident during the early grower stage, which allows for greater savings to the producer

  14. Increased urinary excretion of analogs of Krebs cycle metabolites and arabinose in two brothers with autistic features.

    PubMed

    Shaw, W; Kassen, E; Chaves, E

    1995-08-01

    A marked increase in analogs of Krebs cycle metabolites was found in the urine of two brothers with autistic features. These metabolites included citramalic, tartaric (3-OH-malic), and 3-oxoglutaric acids and compounds tentatively identified as a citric acid analog and partially identified as a phenylcarboxylic acid by the fragmentation pattern of the trimethylsilyl (TMS) derivatives of the compounds and mass shifts of the same compounds derivatized with perdeuterated N,O-bis(trimethylsilyl)trifluoroacetamide. The molecular mass of the TMS derivative of the tentatively identified citric acid analog was 596 Da, based on a finding of a significant M - 15 ion at m/z 581. The citric acid analog was excreted in quantities as high as 137 mmol/mol creatinine, based on the response factor of citric acid as a surrogate calibrator. A carbohydrate with a retention time and mass spectrum identical to arabinose was also found in high concentrations in the urine of these brothers. PMID:7628083

  15. L-Arabinose binding, isomerization, and epimerization by D-xylose isomerase: X-ray/neutron crystallographic and molecular simulation study.

    PubMed

    Langan, Paul; Sangha, Amandeep K; Wymore, Troy; Parks, Jerry M; Yang, Zamin Koo; Hanson, B Leif; Fisher, Zoe; Mason, Sax A; Blakeley, Matthew P; Forsyth, V Trevor; Glusker, Jenny P; Carrell, Horace L; Smith, Jeremy C; Keen, David A; Graham, David E; Kovalevsky, Andrey

    2014-09-01

    D-xylose isomerase (XI) is capable of sugar isomerization and slow conversion of some monosaccharides into their C2-epimers. We present X-ray and neutron crystallographic studies to locate H and D atoms during the respective isomerization and epimerization of L-arabinose to L-ribulose and L-ribose, respectively. Neutron structures in complex with cyclic and linear L-arabinose have demonstrated that the mechanism of ring-opening is the same as for the reaction with D-xylose. Structural evidence and QM/MM calculations show that in the reactive Michaelis complex L-arabinose is distorted to the high-energy (5)S1 conformation; this may explain the apparent high KM for this sugar. MD-FEP simulations indicate that amino acid substitutions in a hydrophobic pocket near C5 of L-arabinose can enhance sugar binding. L-ribulose and L-ribose were found in furanose forms when bound to XI. We propose that these complexes containing Ni(2+) cofactors are Michaelis-like and the isomerization between these two sugars proceeds via a cis-ene-diol mechanism. PMID:25132082

  16. Investigation of the interconversion of L­arabinose and D­xylose as regulated by candidate pathway genes in Beta vulgaris using comparative genomics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Arabinose and xylose occur in hemicellulose, a group of polysaccharides present in plant cell walls in all terrestrial plants. Xylose is an aldopentose sugar with uses as a chemical feedstock, and this study sought to explore the possibility of using sugar beet as an industrial source of xylose, wh...

  17. The acid-tolerant L-arabinose isomerase from the mesophilic Shewanella sp. ANA-3 is highly active at low temperatures

    PubMed Central

    2011-01-01

    Background L-arabinose isomerases catalyse the isomerization of L-arabinose into L-ribulose at insight biological systems. At industrial scale of this enzyme is used for the bioconversion of D-galactose into D-tagatose which has many applications in pharmaceutical and agro-food industries. The isomerization reaction is thermodynamically equilibrated, and therefore the bioconversion rates is shifted towards tagatose when the temperature is increased. Moreover, to prevent secondary reactions it will be of interest to operate at low pH. The profitability of this D-tagatose production process is mainly related to the use of lactose as cheaper raw material. In many dairy products it will be interesting to produce D-tagatose during storage. This requires an efficient L-arabinose isomerase acting at low temperature and pH values. Results The gene encoding the L-arabinose isomerase from Shewanella sp. ANA-3 was cloned and overexpressed in Escherichia coli. The purified protein has a tetrameric arrangement composed by four identical 55 kDa subunits. The biochemical characterization of this enzyme showed that it was distinguishable by its maximal activity at low temperatures comprised between 15-35°C. Interestingly, this biocatalyst preserves more than 85% of its activity in a broad range of temperatures from 4.0 to 45°C. Shewanella sp. ANA-3 L-arabinose isomerase was also optimally active at pH 5.5-6.5 and maintained over 80% of its activity at large pH values from 4.0 to 8.5. Furthermore, this enzyme exhibited a weak requirement for metallic ions for its activity evaluated at 0.6 mM Mn2+. Stability studies showed that this protein is highly stable mainly at low temperature and pH values. Remarkably, T268K mutation clearly enhances the enzyme stability at low pH values. Use of this L-arabinose isomerase for D-tagatose production allows the achievement of attractive bioconversion rates of 16% at 4°C and 34% at 35°C. Conclusions Here we reported the purification and the

  18. Genetics, Transcriptional Profiles, and Catalytic Properties of the UDP-Arabinose Mutase Family from Barley.

    PubMed

    Hsieh, Yves S Y; Zhang, Qisen; Yap, Kuok; Shirley, Neil J; Lahnstein, Jelle; Nelson, Clark J; Burton, Rachel A; Millar, A Harvey; Bulone, Vincent; Fincher, Geoffrey B

    2016-01-19

    Four members of the UDP-Ara mutase (UAM) gene family from barley have been isolated and characterized, and their map positions on chromosomes 2H, 3H, and 4H have been defined. When the genes are expressed in Escherichia coli, the corresponding HvUAM1, HvUAM2, and HvUAM3 proteins exhibit UAM activity, and the kinetic properties of the enzymes have been determined, including Km, Kcat, and catalytic efficiencies. However, the expressed HvUAM4 protein shows no mutase activity against UDP-Ara or against a broad range of other nucleotide sugars and related molecules. The enzymic data indicate therefore that the HvUAM4 protein may not be a mutase. However, the HvUAM4 gene is transcribed at high levels in all the barley tissues examined, and its transcript abundance is correlated with transcript levels for other genes involved in cell wall biosynthesis. The UDP-l-Arap → UDP-l-Araf reaction, which is essential for the generation of the UDP-Araf substrate for arabinoxylan, arabinogalactan protein, and pectic polysaccharide biosynthesis, is thermodynamically unfavorable and has an equilibrium constant of 0.02. Nevertheless, the incorporation of Araf residues into nascent polysaccharides clearly occurs at biologically appropriate rates. The characterization of the HvUAM genes opens the way for the manipulation of both the amounts and fine structures of heteroxylans in cereals, grasses, and other crop plants, with a view toward enhancing their value in human health and nutrition, and in renewable biofuel production. PMID:26645466

  19. Microflow liquid chromatography coupled to mass spectrometry--an approach to significantly increase sensitivity, decrease matrix effects, and reduce organic solvent usage in pesticide residue analysis.

    PubMed

    Uclés Moreno, Ana; Herrera López, Sonia; Reichert, Barbara; Lozano Fernández, Ana; Hernando Guil, María Dolores; Fernández-Alba, Amadeo Rodríguez

    2015-01-20

    This manuscript reports a new pesticide residue analysis method employing a microflow-liquid chromatography system coupled to a triple quadrupole mass spectrometer (microflow-LC-ESI-QqQ-MS). This uses an electrospray ionization source with a narrow tip emitter to generate smaller droplets. A validation study was undertaken to establish performance characteristics for this new approach on 90 pesticide residues, including their degradation products, in three commodities (tomato, pepper, and orange). The significant benefits of the microflow-LC-MS/MS-based method were a high sensitivity gain and a notable reduction in matrix effects delivered by a dilution of the sample (up to 30-fold); this is as a result of competition reduction between the matrix compounds and analytes for charge during ionization. Overall robustness and a capability to withstand long analytical runs using the microflow-LC-MS system have been demonstrated (for 100 consecutive injections without any maintenance being required). Quality controls based on the results of internal standards added at the samples' extraction, dilution, and injection steps were also satisfactory. The LOQ values were mostly 5 μg kg(-1) for almost all pesticide residues. Other benefits were a substantial reduction in solvent usage and waste disposal as well as a decrease in the run-time. The method was successfully applied in the routine analysis of 50 fruit and vegetable samples labeled as organically produced. PMID:25495653

  20. The Cell Wall Arabinose-Deficient Arabidopsis thaliana Mutant murus5 Encodes a Defective Allele of REVERSIBLY GLYCOSYLATED POLYPEPTIDE21[OPEN

    PubMed Central

    Dugard, Christopher K.; Olek, Anna T.; Cooper, Bruce R.

    2016-01-01

    Traditional marker-based mapping and next-generation sequencing was used to determine that the Arabidopsis (Arabidopsis thaliana) low cell wall arabinose mutant murus5 (mur5) encodes a defective allele of REVERSIBLY GLYCOSYLATED POLYPEPTIDE2 (RGP2). Marker analysis of 13 F2 confirmed mutant progeny from a recombinant mapping population gave a rough map position on the upper arm of chromosome 5, and deep sequencing of DNA from these 13 lines gave five candidate genes with G→A (C→T) transitions predicted to result in amino acid changes. Of these five, only insertional mutant alleles of RGP2, a gene that encodes a UDP-arabinose mutase that interconverts UDP-arabinopyranose and UDP-arabinofuranose, exhibited the low cell wall arabinose phenotype. The identities of mur5 and two SALK insertional alleles were confirmed by allelism tests and overexpression of wild-type RGP2 complementary DNA placed under the control of the 35S promoter in the three alleles. The mur5 mutation results in the conversion of cysteine-257 to tyrosine-257 within a conserved hydrophobic cluster predicted to be distal to the active site and essential for protein stability and possible heterodimerization with other isoforms of RGP. PMID:27217494

  1. Crystal Structure of Mn2+-bound Escherichia coli L-arabinose Isomerase (ECAI) and Implications in Protein Catalytic Mechanism and Thermo-Stability

    SciTech Connect

    Zhu,W.; Manjasetty, B.; Chance, M.

    2007-01-01

    The functional properties of proteins depend on their three-dimensional shapes. Protein structures can be determined by X-ray crystallography as a tool. The three-dimensional structure of the apo form of the Escherichia coli L-arabinose isomerase (ECAI) has recently been determined. ECAI is responsible for the initial stage of L-arabinose catabolism, converting arabinose into ribulose in vivo. This enzyme also plays a crucial role in catalyzing the conversion of galactose into tagatose (low calorie natural sugar) in vitro. ECAI utilizes Mn{sup 2+} for its catalytic activity. Crystals of the ECAI + Mn{sup 2+} complex helps to investigate the catalytic properties of the enzyme. Therefore, crystals of ECAI + Mn{sup 2+} complex were grown using hanging drop vapor diffusion method at room temperature. Diffraction data were collected at X4C beamline, National Synchrotron Light Source, Brookhaven National Laboratory. The structure was solved by the molecular replacement technique and has been refined to Rwork of 0.23 at 2.8 {angstrom} resolution using X3A beamline computational facility. The structure was deposited to Protein Data Bank (PDB ID 2HXG). Mn{sup 2+} ion was localized to the previously identified putative active site with octahedral coordination. Comparison of apo and holo form of ECAI structures permits the identification of structural features that are of importance to the intrinsic activity and heat stability of AI.

  2. Boost the electron mobility of solution-grown organic single crystals via reducing the amount of polar solvent residues

    SciTech Connect

    Xue, Guobiao; Xin, Huolin L.; Wu, Jiake; Fan, Congcheng; Liu, Shuang; Huang, Zhuoting; Liu, Yujing; Shan, Bowen; Miao, Qian; Chen, Hongzheng; Li, Hanying

    2015-10-29

    Enhancing electron transport to match with the development in hole transport is critical for organic electronics in the future. As electron motion is susceptible to extrinsic factors, seeking these factors and avoiding their negative effects have become the central challenge. Here, the existence of polar solvent residues in solution-grown single-crystals of 6,13-bis(triisopropylsilylethynyl)-5,7,12,14-tetraazapentacene is identified as a factor detrimental to electron motion. Field-effect transistors of the crystals exhibit electron mobility boosted by about 60% after the residues are removed. The average electron mobility reaches up to 8.0 ± 2.2 cm2 V–1 s–1 with a highest value of 13.3 cm2 V–1 s–1; these results are significantly higher than those obtained previously for the same molecule (1.0–5.0 cm2 V–1 s–1). Furthermore, the achieved mobility is also higher than the maximum reported electron mobility for organic materials (11 cm2 V–1 s–1). As a result, this work should greatly accelerate the advancement of organic electron-transporting materials.

  3. Analysis of organo-chlorine pesticides residue in raw coffee with a modified "quick easy cheap effective rugged and safe" extraction/clean up procedure for reducing the impact of caffeine on the gas chromatography-mass spectrometry measurement.

    PubMed

    Bresin, Bruno; Piol, Maria; Fabbro, Denis; Mancini, Maria Antonietta; Casetta, Bruno; Del Bianco, Clorinda

    2015-01-01

    The control of pesticide residues on raw coffee is a task of great importance due to high consumption of this beverage in Italy and in many other countries. High caffeine content can hamper extraction and measurement of any pesticide residue. A tandem extraction protocol has been devised by exploiting the quick easy cheap effective rugged and safe (QuEChERS) scheme for extraction, coupled to a dispersive liquid-liquid micro-extraction (DLLME) in order to drastically reduce caffeine content in the final extract. Gas chromatography-mass spectrometry (GC-MS) has been used for quantification of organo-chlorine pesticides in single ion monitoring (SIM) mode. Method has been validated and performances meet the criteria prescribed by European Union regulations. PMID:25537171

  4. Biochar from Sugarcane Filtercake Reduces Soil CO2 Emissions Relative to Raw Residue and Improves Water Retention and Nutrient Availability in a Highly-Weathered Tropical Soil

    PubMed Central

    Eykelbosh, Angela Joy; Johnson, Mark S.; Santos de Queiroz, Edmar; Dalmagro, Higo José; Guimarães Couto, Eduardo

    2014-01-01

    In Brazil, the degradation of nutrient-poor Ferralsols limits productivity and drives agricultural expansion into pristine areas. However, returning agricultural residues to the soil in a stabilized form may offer opportunities for maintaining or improving soil quality, even under conditions that typically promote carbon loss. We examined the use of biochar made from filtercake (a byproduct of sugarcane processing) on the physicochemical properties of a cultivated tropical soil. Filtercake was pyrolyzed at 575°C for 3 h yielding a biochar with increased surface area and porosity compared to the raw filtercake. Filtercake biochar was primarily composed of aromatic carbon, with some residual cellulose and hemicellulose. In a three-week laboratory incubation, CO2 effluxes from a highly weathered Ferralsol soil amended with 5% biochar (dry weight, d.w.) were roughly four-fold higher than the soil-only control, but 23-fold lower than CO2 effluxes from soil amended with 5% (d.w.) raw filtercake. We also applied vinasse, a carbon-rich liquid waste from bioethanol production typically utilized as a fertilizer on sugarcane soils, to filtercake- and biochar-amended soils. Total CO2 efflux from the biochar-amended soil in response to vinasse application was only 5% of the efflux when vinasse was applied to soil amended with raw filtercake. Furthermore, mixtures of 5 or 10% biochar (d.w.) in this highly weathered tropical soil significantly increased water retention within the plant-available range and also improved nutrient availability. Accordingly, application of sugarcane filtercake as biochar, with or without vinasse application, may better satisfy soil management objectives than filtercake applied to soils in its raw form, and may help to build soil carbon stocks in sugarcane-cultivating regions. PMID:24897522

  5. Biochar from sugarcane filtercake reduces soil CO2 emissions relative to raw residue and improves water retention and nutrient availability in a highly-weathered tropical soil.

    PubMed

    Eykelbosh, Angela Joy; Johnson, Mark S; Santos de Queiroz, Edmar; Dalmagro, Higo José; Guimarães Couto, Eduardo

    2014-01-01

    In Brazil, the degradation of nutrient-poor Ferralsols limits productivity and drives agricultural expansion into pristine areas. However, returning agricultural residues to the soil in a stabilized form may offer opportunities for maintaining or improving soil quality, even under conditions that typically promote carbon loss. We examined the use of biochar made from filtercake (a byproduct of sugarcane processing) on the physicochemical properties of a cultivated tropical soil. Filtercake was pyrolyzed at 575°C for 3 h yielding a biochar with increased surface area and porosity compared to the raw filtercake. Filtercake biochar was primarily composed of aromatic carbon, with some residual cellulose and hemicellulose. In a three-week laboratory incubation, CO2 effluxes from a highly weathered Ferralsol soil amended with 5% biochar (dry weight, d.w.) were roughly four-fold higher than the soil-only control, but 23-fold lower than CO2 effluxes from soil amended with 5% (d.w.) raw filtercake. We also applied vinasse, a carbon-rich liquid waste from bioethanol production typically utilized as a fertilizer on sugarcane soils, to filtercake- and biochar-amended soils. Total CO2 efflux from the biochar-amended soil in response to vinasse application was only 5% of the efflux when vinasse was applied to soil amended with raw filtercake. Furthermore, mixtures of 5 or 10% biochar (d.w.) in this highly weathered tropical soil significantly increased water retention within the plant-available range and also improved nutrient availability. Accordingly, application of sugarcane filtercake as biochar, with or without vinasse application, may better satisfy soil management objectives than filtercake applied to soils in its raw form, and may help to build soil carbon stocks in sugarcane-cultivating regions. PMID:24897522

  6. Use of Interface Treatment to Reduce Emissions from Residuals in Lower Permeability Zones to Groundwater flowing Through More Permeable Zones (Invited)

    NASA Astrophysics Data System (ADS)

    Johnson, P.; Cavanagh, B.; Clifton, L.; Daniels, E.; Dahlen, P.

    2013-12-01

    Many soil and groundwater remediation technologies rely on fluid flow for contaminant extraction or reactant delivery (e.g., soil vapor extraction, pump and treat, in situ chemical oxidation, air sparging, enhanced bioremediation). Given that most unconsolidated and consolidated settings have permeability contrasts, the outcome is often preferential treatment of more permeable zones and ineffective treatment of the lower permeability zones. When this happens, post-treatment contaminant emissions from low permeability zone residuals can cause unacceptable long-term impacts to groundwater in the transmissive zones. As complete remediation of the impacted lower permeability zones may not be practicable with conventional technologies, one might explore options that lead to reduction of the contaminant emissions to acceptable levels, rather than full remediation of the lower permeability layers. This could be accomplished either by creating a sustained emission reaction/attenuation zone at the high-low permeability interface, or by creating a clean soil zone extending sufficiently far into the lower permeability layer to cause the necessary reduction in contaminant concentration gradient and diffusive emission. These options are explored in proof-of-concept laboratory-scale physical model experiments. The physical models are prepared with two layers of contrasting permeability and either dissolved matrix storage or nonaqueous phase liquid (NAPL) in the lower permeability layer. A dissolved oxidant is then delivered to the interface via flow across the higher permeability layer and changes in contaminant emissions from the low permeability zone are monitored before, during, and after oxidant delivery. The use of three oxidants (dissolved oxygen, hydrogen peroxide and sodium persulfate) for treatment of emissions from petroleum hydrocarbon residuals is examined.

  7. Identification of a Novel Mycobacterial Arabinosyltransferase Activity Which Adds an Arabinosyl Residue to α-d-Mannosyl Residues.

    PubMed

    Angala, Shiva Kumar; McNeil, Michael R; Zou, Lu; Liav, Avraham; Zhang, Junfeng; Lowary, Todd L; Jackson, Mary

    2016-06-17

    The arabinosyltransferases responsible for the biosynthesis of the arabinan domains of two abundant heteropolysaccharides of the cell envelope of all mycobacterial species, lipoarabinomannan and arabinogalactan, are validated drug targets. Using a cell envelope preparation from Mycobacterium smegmatis as the enzyme source and di- and trimannoside synthetic acceptors, we uncovered a previously undetected arabinosyltransferase activity. Thin layer chromatography, GC/MS, and LC/MS/MS analyses of the major enzymatic product are consistent with the transfer of an arabinose residue to the 6 position of the terminal mannosyl residue at the nonreducing end of the acceptors. The newly identified enzymatic activity is resistant to ethambutol and could correspond to the priming arabinosyl transfer reaction that occurs during lipoarabinomannan biosynthesis. PMID:27045860

  8. Optimization of acid hydrolysis from the hemicellulosic fraction of Eucalyptus grandis residue using response surface methodology.

    PubMed

    Canettieri, Eliana Vieira; de Moraes Rocha, George Jackson; de Carvalho, João Andrade; de Almeida e Silva, João Batista

    2007-01-01

    Biotechnological conversion of biomass into fuels and chemicals requires hydrolysis of the polysaccharide fraction into monomeric sugars. Hydrolysis can be performed enzymatically and with dilute or concentrate mineral acids. The present study used dilute sulfuric acid as a catalyst for hydrolysis of Eucalyptus grandis residue. The purpose of this paper was to optimize the hydrolysis process in a 1.4 l pilot-scale reactor and investigate the effects of the acid concentration, temperature and residue/acid solution ratio on the hemicellulose removal and consequently on the production of sugars (xylose, glucose and arabinose) as well as on the formation of by-products (furfural, 5-hydroxymethylfurfural and acetic acid). This study was based on a model composition corresponding to a 2(3) orthogonal factorial design and employed the response surface methodology (RSM) to optimize the hydrolysis conditions, aiming to attain maximum xylose extraction from hemicellulose of residue. The considered optimum conditions were: H(2)SO(4) concentration of 0.65%, temperature of 157 degrees C and residue/acid solution ratio of 1/8.6 with a reaction time of 20 min. Under these conditions, 79.6% of the total xylose was removed and the hydrolysate contained 1.65 g/l glucose, 13.65 g/l xylose, 1.55 g/l arabinose, 3.10 g/l acetic acid, 1.23 g/l furfural and 0.20 g/l 5-hydroxymethylfurfural. PMID:16473004

  9. Assessment of agro-industrial and composted organic wastes for reducing the potential leaching of triazine herbicide residues through the soil.

    PubMed

    Fenoll, José; Vela, Nuria; Navarro, Ginés; Pérez-Lucas, Gabriel; Navarro, Simón

    2014-09-15

    In this study, we examined the effect of four different organic wastes--composted sheep manure (CSM), spent coffee grounds (SCG), composted pine bark (CPB) and coir (CR)--on the sorption, persistence and mobility of eight symmetrical and two asymmetrical-triazine herbicides: atrazine, propazine, simazine, terbuthylazine (chlorotriazines), prometon (methoxytriazine), prometryn, simetryn, terbutryn (methylthiotriazines), metamitron and metribuzin (triazinones). The downward movement of herbicides was monitored using disturbed soil columns packed with a clay loam soil (Hipercalcic calcisol) under laboratory conditions. For unamended and amended soils, the groundwater ubiquity score (GUS) was calculated for each herbicide on the basis of its persistence (as t½) and mobility (as KOC). All herbicides showed medium/high leachability through the unamended soils. The addition of agro-industrial and composted organic wastes at a rate of 10% (w:w) strongly decreased the mobility of herbicides. Sorption coefficients normalized to the total soil organic carbon (KOC) increased in the amended soils. These results suggest that used organic wastes could be used to enhance the retention and reduce the mobility of the studied herbicides in soil. PMID:24937498

  10. Impact of Residual Inducer on Titratable Expression Systems

    PubMed Central

    Afroz, Taliman; Luo, Michelle L.; Beisel, Chase L.

    2015-01-01

    Inducible expression systems are widely employed for the titratable control of gene expression, yet molecules inadvertently present in the growth medium or synthesized by the host cells can alter the response profile of some of these systems. Here, we explored the quantitative impact of these residual inducers on the apparent response properties of inducible systems. Using a simple mathematical model, we found that the presence of residual inducer shrinks the apparent dynamic range and causes the apparent Hill coefficient to converge to one. We also found that activating systems were more sensitive than repressing systems to the presence of residual inducer and the response parameters were most heavily dependent on the original Hill coefficient. Experimental interrogation of common titratable systems based on an L-arabinose inducible promoter or a thiamine pyrophosphate-repressing riboswitch in Escherichia coli confirmed the predicted trends. We finally found that residual inducer had a distinct effect on “all-or-none” systems, which exhibited increased sensitivity to the added inducer until becoming fully induced. Our findings indicate that residual inducer or repressor alters the quantitative response properties of titratable systems, impacting their utility for scientific discovery and pathway engineering. PMID:26348036

  11. Impact of Residual Inducer on Titratable Expression Systems.

    PubMed

    Afroz, Taliman; Luo, Michelle L; Beisel, Chase L

    2015-01-01

    Inducible expression systems are widely employed for the titratable control of gene expression, yet molecules inadvertently present in the growth medium or synthesized by the host cells can alter the response profile of some of these systems. Here, we explored the quantitative impact of these residual inducers on the apparent response properties of inducible systems. Using a simple mathematical model, we found that the presence of residual inducer shrinks the apparent dynamic range and causes the apparent Hill coefficient to converge to one. We also found that activating systems were more sensitive than repressing systems to the presence of residual inducer and the response parameters were most heavily dependent on the original Hill coefficient. Experimental interrogation of common titratable systems based on an L-arabinose inducible promoter or a thiamine pyrophosphate-repressing riboswitch in Escherichia coli confirmed the predicted trends. We finally found that residual inducer had a distinct effect on "all-or-none" systems, which exhibited increased sensitivity to the added inducer until becoming fully induced. Our findings indicate that residual inducer or repressor alters the quantitative response properties of titratable systems, impacting their utility for scientific discovery and pathway engineering. PMID:26348036

  12. Crop residues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop residues [e.g., corn (Zea mays) stover and small grain straw] are sometimes excluded when discussing cellulosic energy crops per se, but because of the vast area upon which they are grown and their current role in the development of cellulosic energy systems. This chapter focuses on current cor...

  13. Cellulose microfibril crystallinity is reduced by mutating C-terminal transmembrane region residues CESA1A903V and CESA3T942I of cellulose synthase

    PubMed Central

    Harris, Darby M.; Corbin, Kendall; Wang, Tuo; Gutierrez, Ryan; Bertolo, Ana L.; Petti, Carloalberto; Smilgies, Detlef-M.; Estevez, José Manuel; Bonetta, Dario; Urbanowicz, Breeanna R.; Ehrhardt, David W.; Somerville, Chris R.; Rose, Jocelyn K. C.; Hong, Mei; DeBolt, Seth

    2012-01-01

    The mechanisms underlying the biosynthesis of cellulose in plants are complex and still poorly understood. A central question concerns the mechanism of microfibril structure and how this is linked to the catalytic polymerization action of cellulose synthase (CESA). Furthermore, it remains unclear whether modification of cellulose microfibril structure can be achieved genetically, which could be transformative in a bio-based economy. To explore these processes in planta, we developed a chemical genetic toolbox of pharmacological inhibitors and corresponding resistance-conferring point mutations in the C-terminal transmembrane domain region of CESA1A903V and CESA3T942I in Arabidopsis thaliana. Using 13C solid-state nuclear magnetic resonance spectroscopy and X-ray diffraction, we show that the cellulose microfibrils displayed reduced width and an additional cellulose C4 peak indicative of a degree of crystallinity that is intermediate between the surface and interior glucans of wild type, suggesting a difference in glucan chain association during microfibril formation. Consistent with measurements of lower microfibril crystallinity, cellulose extracts from mutated CESA1A903V and CESA3T942I displayed greater saccharification efficiency than wild type. Using live-cell imaging to track fluorescently labeled CESA, we found that these mutants show increased CESA velocities in the plasma membrane, an indication of increased polymerization rate. Collectively, these data suggest that CESA1A903V and CESA3T942I have modified microfibril structure in terms of crystallinity and suggest that in plants, as in bacteria, crystallization biophysically limits polymerization. PMID:22375033

  14. Magnetic solid phase extraction based on magnetite/reduced graphene oxide nanoparticles for determination of trace isocarbophos residues in different matrices.

    PubMed

    Yan, Shan; Qi, Ting-Ting; Chen, De-Wen; Li, Zhao; Li, Xiu-Juan; Pan, Si-Yi

    2014-06-20

    A simple one-step solvothermal method was applied for the preparation of magnetite/reduced graphene oxide (MRGO), and the synthetic nanocomposites with a magnetic particle size of ∼8nm were used as an adsorbent for magnetic solid phase extraction of isocarbophos (ICP) in different sample matrices prior to gas chromatography (GC) detection. The identity of the nanomaterial was confirmed using Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. It was shown that Fe3O4 nanoparticles with a uniform size were homogeneously anchored on RGO nanosheets. Increased oxidation degrees of graphite oxide, big particle sizes and large loading amounts of Fe3O4 on the surface of RGO led to a decrease of adsorption capacity of MRGO to ICP. The adsorption behavior of this adsorbent was better fitted by the pseudo-second-order kinetic model. Several parameters affecting the extraction efficiency were investigated and optimized, including adsorbent dosage, extraction time, ionic strength and desorption conditions. And then, a rapid and effective method based on MRGO combined with GC was developed for the determination of ICP in aqueous samples. A linear range from 0.05 to 50ngmL(-1) was obtained with a high correlation coefficient (R(2)) of 0.9995, and the limit of detection was found to be 0.0044ngmL(-1). This method was successfully applied to the analysis of ICP in five kinds of samples, including apple, rice, lake water, cowpea and cabbage. The recoveries in different sample matrices were in the range from 81.00% to 108.51% with relative standard deviations less than 9.72%. It can be concluded that the proposed analytical method is highly-efficient, sensitive, precise, accurate and practicable. PMID:24800969

  15. AraR, an l-Arabinose-Responsive Transcriptional Regulator in Corynebacterium glutamicum ATCC 31831, Exerts Different Degrees of Repression Depending on the Location of Its Binding Sites within the Three Target Promoter Regions

    PubMed Central

    Kuge, Takayuki; Teramoto, Haruhiko

    2015-01-01

    ABSTRACT In Corynebacterium glutamicum ATCC 31831, a LacI-type transcriptional regulator AraR, represses the expression of l-arabinose catabolism (araBDA), uptake (araE), and the regulator (araR) genes clustered on the chromosome. AraR binds to three sites: one (BSB) between the divergent operons (araBDA and galM-araR) and two (BSE1 and BSE2) upstream of araE. l-Arabinose acts as an inducer of the AraR-mediated regulation. Here, we examined the roles of these AraR-binding sites in the expression of the AraR regulon. BSB mutation resulted in derepression of both araBDA and galM-araR operons. The effects of BSE1 and/or BSE2 mutation on araE expression revealed that the two sites independently function as the cis elements, but BSE1 plays the primary role. However, AraR was shown to bind to these sites with almost the same affinity in vitro. Taken together, the expression of araBDA and araE is strongly repressed by binding of AraR to a single site immediately downstream of the respective transcriptional start sites, whereas the binding site overlapping the −10 or −35 region of the galM-araR and araE promoters is less effective in repression. Furthermore, downregulation of araBDA and araE dependent on l-arabinose catabolism observed in the BSB mutant and the AraR-independent araR promoter identified within galM-araR add complexity to regulation of the AraR regulon derepressed by l-arabinose. IMPORTANCE Corynebacterium glutamicum has a long history as an industrial workhorse for large-scale production of amino acids. An important aspect of industrial microorganisms is the utilization of the broad range of sugars for cell growth and production process. Most C. glutamicum strains are unable to use a pentose sugar l-arabinose as a carbon source. However, genes for l-arabinose utilization and its regulation have been recently identified in C. glutamicum ATCC 31831. This study elucidates the roles of the multiple binding sites of the transcriptional repressor AraR in the

  16. Conversion of hemicellulose sugars catalyzed by formic acid: kinetics of the dehydration of D-xylose, L-arabinose, and D-glucose.

    PubMed

    Dussan, Karla; Girisuta, Buana; Lopes, Marystela; Leahy, James J; Hayes, Michael H B

    2015-04-24

    The pre-treatment of lignocellulosic biomass produces a liquid stream of hemicellulose-based sugars, which can be further converted to high-value chemicals. Formosolv pulping and the Milox process use formic acid as the fractionating agent, which can be used as the catalyst for the valorisation of hemicellulose sugars to platform chemicals. The objective of this study was to investigate the reaction kinetics of major components in the hemicelluloses fraction of biomass, that is, D-xylose, L-arabinose and D-glucose. The kinetics experiments for each sugar were performed at temperatures between 130 and 170 °C in various formic acid concentrations (10-64 wt %). The implications of these kinetic models on the selectivity of each sugar to the desired products are discussed. The models were used to predict the reaction kinetics of solutions that resemble the liquid stream obtained from the fractionation process of biomass using formic acid. PMID:25821128

  17. Crystal structures of two monomeric triosephosphate isomerase variants identified via a directed-evolution protocol selecting for L-arabinose isomerase activity.

    PubMed

    Krause, Mirja; Kiema, Tiila Riikka; Neubauer, Peter; Wierenga, Rik K

    2016-06-01

    The crystal structures are described of two variants of A-TIM: Ma18 (2.7 Å resolution) and Ma21 (1.55 Å resolution). A-TIM is a monomeric loop-deletion variant of triosephosphate isomerase (TIM) which has lost the TIM catalytic properties. Ma18 and Ma21 were identified after extensive directed-evolution selection experiments using an Escherichia coli L-arabinose isomerase knockout strain expressing a randomly mutated A-TIM gene. These variants facilitate better growth of the Escherichia coli selection strain in medium supplemented with 40 mM L-arabinose. Ma18 and Ma21 differ from A-TIM by four and one point mutations, respectively. Ma18 and Ma21 are more stable proteins than A-TIM, as judged from CD melting experiments. Like A-TIM, both proteins are monomeric in solution. In the Ma18 crystal structure loop 6 is open and in the Ma21 crystal structure loop 6 is closed, being stabilized by a bound glycolate molecule. The crystal structures show only small differences in the active site compared with A-TIM. In the case of Ma21 it is observed that the point mutation (Q65L) contributes to small structural rearrangements near Asn11 of loop 1, which correlate with different ligand-binding properties such as a loss of citrate binding in the active site. The Ma21 structure also shows that its Leu65 side chain is involved in van der Waals interactions with neighbouring hydrophobic side-chain moieties, correlating with its increased stability. The experimental data suggest that the increased stability and solubility properties of Ma21 and Ma18 compared with A-TIM cause better growth of the selection strain when coexpressing Ma21 and Ma18 instead of A-TIM. PMID:27303904

  18. Residual Cap

    NASA Technical Reports Server (NTRS)

    2006-01-01

    10 May 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a summertime view of the south polar residual cap of Mars. In this image, mesas composed largely of solid carbon dioxide are separated from one another by irregularly-shaped depressions. The variation in brightness across this scene is a function of several factors including, but not limited to, varying proportions of dust and solid carbon dioxide, undulating topography, and differences in the roughness of the slopes versus the flat surfaces.

    Location near: 86.7oS, 343.3oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Southern Summer

  19. Insecticidal Activity of Some Reducing Sugars Against the Sweet Potato Whitefly, Bemisia tabaci, Biotype B

    PubMed Central

    Hu, Jing S.; Gelman, Dale B.; Salvucci, Michael E.; Chen, Yan P.; Blackburn, Michael B.

    2010-01-01

    The effects of 16 sugars (arabinose, cellobiose, fructose, galactose, gentiobiose, glucose, inositol, lactose, maltose, mannitol (a sugar alcohol), mannose, melibiose, ribose, sorbitol, trehalose, and xylose) on sweet potato whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) survival were determined using in vitro bioassays. Of these sugars, arabinose, mannose, ribose, and xylose were strongly inhibitory to both nymphal and adult survival. When 10% mannose was added to the nymphal diet, 10.5%, 1.0%, and 0% developed to the 2nd, 3rd, and 4th instars, respectively. When 10% arabinose was added, 10.8% and 0% of the nymphs molted to the 2nd and 3rd instars, respectively. Addition of 10% xylose or ribose completely terminated B. tabaci development, preventing the molt to the 2nd instar. With decreasing sugar concentrations the inhibitory effect was significantly reduced. In tests using adults, arabinose, galactose, inositol, lactose, maltose, mannitol, mannose, melibiose, ribose, sorbitol, trehalose, and xylose significantly reduced mean day survival. Mortality rates were highest when arabinose, mannitol, mannose, ribose, or xylose was added to the diet. Mean day survival was less than 2 days when adults were fed on diet containing 10% of any one of these five sugars. When lower concentrations of sugars were used there was a decrease in mortality. Mode of action studies revealed that toxicity was not due to the inhibition of alpha glucosidase (converts sucrose to glucose and fructose) and/or trehalulose synthase (converts sucrose to trehalulose) activity. The result of agarose gel electrophoresis of RT-PCR products of bacterial endosymbionts amplified from RNA isolated from whiteflies fed with 10% arabinose, mannose, or xylose indicated that the concentration of endosymbionts in mycetomes was not affected by the toxic sugars. Experiments in which B. tabaci were fed on diets that contained radio-labeled sucrose, methionine or inulin and one or none (control) of

  20. A method for the production of D-tagatose using a recombinant Pichia pastoris strain secreting β-D-galactosidase from Arthrobacter chlorophenolicus and a recombinant L-arabinose isomerase from Arthrobacter sp. 22c

    PubMed Central

    2012-01-01

    Background D-Tagatose is a natural monosaccharide which can be used as a low-calorie sugar substitute in food, beverages and pharmaceutical products. It is also currently being tested as an anti-diabetic and obesity control drug. D-Tagatose is a rare sugar, but it can be manufactured by the chemical or enzymatic isomerization of D-galactose obtained by a β-D-galactosidase-catalyzed hydrolysis of milk sugar lactose and the separation of D-glucose and D-galactose. L-Arabinose isomerases catalyze in vitro the conversion of D-galactose to D-tagatose and are the most promising enzymes for the large-scale production of D-tagatose. Results In this study, the araA gene from psychrotolerant Antarctic bacterium Arthrobacter sp. 22c was isolated, cloned and expressed in Escherichia coli. The active form of recombinant Arthrobacter sp. 22c L-arabinose isomerase consists of six subunits with a combined molecular weight of approximately 335 kDa. The maximum activity of this enzyme towards D-galactose was determined as occurring at 52°C; however, it exhibited over 60% of maximum activity at 30°C. The recombinant Arthrobacter sp. 22c L-arabinose isomerase was optimally active at a broad pH range of 5 to 9. This enzyme is not dependent on divalent metal ions, since it was only marginally activated by Mg2+, Mn2+ or Ca2+ and slightly inhibited by Co2+ or Ni2+. The bioconversion yield of D-galactose to D-tagatose by the purified L-arabinose isomerase reached 30% after 36 h at 50°C. In this study, a recombinant Pichia pastoris yeast strain secreting β-D-galactosidase Arthrobacter chlorophenolicus was also constructed. During cultivation of this strain in a whey permeate, lactose was hydrolyzed and D-glucose was metabolized, whereas D-galactose was accumulated in the medium. Moreover, cultivation of the P. pastoris strain secreting β-D-galactosidase in a whey permeate supplemented with Arthrobacter sp. 22c L-arabinose isomerase resulted in a 90% yield of lactose hydrolysis, the

  1. Chemical improvement of chitosan-modified beads for the immobilization of Enterococcus faecium DBFIQ E36 L-arabinose isomerase through multipoint covalent attachment approach.

    PubMed

    Manzo, Ricardo M; de Sousa, Marylane; Fenoglio, Cecilia L; Gonçalves, Luciana Rocha Barro; Mammarella, Enrique J

    2015-10-01

    D-tagatose is produced from D-galactose by the enzyme L-arabinose isomerase (L-AI) in a commercially viable bioprocess. An active and stable biocatalyst was obtained by modifying chitosan gel structure through reaction with TNBS, D-fructose or DMF, among others. This led to a significant improvement in L-AI immobilization via multipoint covalent attachment approach. Synthetized derivatives were compared with commercial supports such as Eupergit(®) C250L and glyoxal-agarose. The best chitosan derivative for L-AI immobilization was achieved by reacting 4 % (w/v) D-fructose with 3 % (w/v) chitosan at 50 °C for 4 h. When compared to the free enzyme, the glutaraldehyde-activated chitosan biocatalyst showed an apparent activity of 88.4 U g (gel) (-1) with a 211-fold stabilization factor while the glyoxal-agarose biocatalyst gave an apparent activity of 161.8 U g (gel) (-1) with an 85-fold stabilization factor. Hence, chitosan derivatives were comparable to commercial resins, thus becoming a viable low-cost strategy to obtain high active L-AI insolubilized derivatives. PMID:26254040

  2. Optical systolic array processor using residue arithmetic

    NASA Technical Reports Server (NTRS)

    Jackson, J.; Casasent, D.

    1983-01-01

    The use of residue arithmetic to increase the accuracy and reduce the dynamic range requirements of optical matrix-vector processors is evaluated. It is determined that matrix-vector operations and iterative algorithms can be performed totally in residue notation. A new parallel residue quantizer circuit is developed which significantly improves the performance of the systolic array feedback processor. Results are presented of a computer simulation of this system used to solve a set of three simultaneous equations.

  3. Soil water evaporation and crop residues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop residues have value when left in the field and also when removed from the field and sold as a commodity. Reducing soil water evaporation (E) is one of the benefits of leaving crop residues in place. E was measured beneath a corn canopy at the soil suface with nearly full coverage by corn stover...

  4. An EBV recombinant deleted for residues 130-159 in EBNA3C can deregulate p53/Mdm2 and Cyclin D1/CDK6 which results in apoptosis and reduced cell proliferation

    PubMed Central

    El-Naccache, Darine W.; Robertson, Erle S.

    2016-01-01

    Epstein-Barr virus (EBV), a gamma herpes virus is associated with B-cell malignancies. EBNA-3C is critical for in vitro primary B-cell transformation. Interestingly, the N terminal domain of EBNA3C which contains residues 130–159, interacts with various cellular proteins, such as p53, Mdm2, CyclinD1/Cdk6 complex, and E2F1. In the current reverse genetics study, we deleted the residues 130-159 aa within EBNA3C open reading frame (ORF) by BACmid recombinant engineering methodology. Our experiments demonstrated that deletion of the 130-159 aa showed a reduction in cell proliferation. Also, this recombinant virus showed with higher infectivity of human peripheral blood mononuclear cells (PBMCs) compared to wild type EBV. PBMCs- infected with recombinant EBV deleted for 130-159 residues have differential expression patterns for the p53/Mdm2, CyclinD1/Cdk6 and pRb/E2F1 pathways compared to wild type EBV-infected PBMCs. PBMCs infected with recombinant virus showed increased apoptotic cell death which further resulted in activation of polymerase 1 (PARP1), an important contributor to apoptotic signaling. Interestingly, cells infected with this recombinant virus showed a dramatic decrease in chromosomal instability, indicated by the presence of increased multinucleation and micronucleation. In addition infection with recombinant virus have increased cells in G0/G1 phase and decreased cells in S-G2M phase when compared to wild type infected cells. Thus, these differences in signaling activities due to 29 amino acid residues of EBNA3C is of particular significance in deregulation of cell proliferation in EBV-infected cells. PMID:26908453

  5. Should the Functional Residual Capacity be Ignored?

    PubMed Central

    Selvi E, Chandra; K.V Rao, Kuppu; Malathi

    2013-01-01

    Aim and Objectives: The functional residual capacity was given the least importance than the other lung volume parameters. Studies have revealed the restrictive pattern of lung disease in patients with liver cirrhosis. We aimed to analyze the importance of the functional residual capacity and other lung volumes of cirrhotic patients. Subjects and Methods: Forty (40) patients with cirrhosis (Child’s-B) were enrolled in this study. The vital capacity was measured by an instrument called V02 Max 22. The other lung volumes which were measured were derived parameters. The functional residual capacity was measured by the nitrogen wash-out method. Results: The measured value of the functional residual capacity was below normal as compared to the reference value. The total lung capacity and the vital capacity were positively correlated with the functional residual capacity. The residual volume was found to be increased in twelve out of forty cirrhotic patients. Conclusion: The functional residual capacity can be determined by the compliance of the lung and the chest wall. The patients with a reduced functional residual capacity may be suffering from dyspnoea, probably due to the restrictive pattern of the lung disease. Hence, the reduced lung volumes of the subjects may be due to the abnormalities in the mechanics of ventilation. PMID:23450122

  6. Sugarcane Post-Harvest Residue Management in Louisiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Failure to remove sugarcane post-harvest residue often reduces ratoon crop yields in temperate climates. A series of experiments was conducted to determine the effects of various residue management practices on sugarcane yield. For the first experiment, timing of post-harvest residue was based on th...

  7. Behavior of peptides combining 1 alanine residue and 8 glycine residues on papain associated with structural fluctuations

    NASA Astrophysics Data System (ADS)

    Nishiyama, Katsuhiko

    2011-12-01

    I investigated the behavior of the peptides combining 1 ALA residue and 8 GLY residues on papain associated with structural fluctuations via molecular dynamics and docking simulations. Although the chance of binding to sites near the active center of papain was reduced by replacing the GLY residue in 9GLY with ALA residue, binding stability was improved by the replacement. Furthermore, both the chance and binding stability were greatly affected by positioning of ALA residue in the peptides. Residue in peptides should be replaced in view of the balance between chance of binding to sites near active center and binding stability.

  8. Process for treatment of residual gas

    SciTech Connect

    Nolden, K.

    1980-01-01

    A process is disclosed for the treatment of the residual gases which are produced when hydrogen sulfide is reduced, by combustion, to elementary sulfur by the Claus process. The residual gases are fed through a heated conduit and gas scrubber, wherein the temperature of those residual gases are maintained above the melting point of sulfur. A portion of the raw coke oven gas condensate is admitted to the gas scrubber to be returned to the coke oven battery main from the flushing liquid separator as flushing liquor. The residual gases are then conducted through the coke oven gas purification process equipment along with the raw coke oven gas where the residual gases are intermixed with the raw coke oven gas prior to tar separation.

  9. Bacteroides propionicifaciens sp. nov., isolated from rice-straw residue in a methanogenic reactor treating waste from cattle farms.

    PubMed

    Ueki, Atsuko; Abe, Kunihiro; Kaku, Nobuo; Watanabe, Kazuya; Ueki, Katsuji

    2008-02-01

    Two strictly anaerobic bacterial strains (SV434(T) and S562) were isolated from rice-straw residue in a methanogenic reactor treating waste from cattle farms in Japan. They had identical 16S rRNA gene sequences and showed almost the same phenotypic properties. The cells of both strains were Gram-negative, non-motile, non-spore-forming rods; extraordinarily long rods often occurred. Remarkable stimulation of growth occurred with the addition of haemin and cobalamin (vitamin B(12)) to the medium. The supplementary cobalamin and haemin could be replaced if autoclaved and clarified sludge fluid obtained from the reactor was added. Both strains utilized a range of growth substrates, including arabinose, fructose, galactose, glucose, mannose, cellobiose, maltose, glycogen, starch, dextrin, amygdalin, lactate and pyruvate. Both strains produced acetate and propionate with a small amount of succinate from these substrates in the presence of haemin and cobalamin. Both strains were slightly alkaliphilic, having a pH optimum at about 7.9. The temperature range for growth was 5-35 degrees C, the optimum being 30 degrees C. The NaCl concentration range for growth was 0-4 % (w/v). Catalase activity was not detected in cells cultivated without haemin, whereas cells cultivated with haemin usually had the enzyme activity. Oxidase and nitrate-reducing activities were not detected. Aesculin was hydrolysed, but gelatin was not hydrolysed. Both strains were sensitive to bile acids. The major cellular fatty acids of both strains were anteiso-C(15 : 0) and iso-C(15 : 0). Menaquinones MK-8(H(0)) and MK-9(H(0)) were the major respiratory quinones and the genomic DNA G+C contents were 46.2-47.5 mol%. A phylogenetic analysis based on 16S rRNA gene sequences placed both strains in the phylum Bacteroidetes. Bacteroides coprosuis (isolated from swine-manure storage pits) was the species most closely related to both strains (95.9 % 16S rRNA gene sequence similarity to the type strain). On the

  10. Effects of processing on carbendazim residue in Pleurotus ostreatus.

    PubMed

    Xia, Erdong; Tao, Wuqun; Yao, Xi; Wang, Jin; Tang, Feng

    2016-07-01

    Samples of Pleurotus ostreatus were exposed to fungicide carbendazim to study the effect of processing on the residues. In most cases, processing operations led to a significant decrease in residue levels in the finished products, particularly through washing, drying, and cooking processes. The results indicated that rinsing under running tap water led to more than 70.30% loss in carbendazim residues. When dried under sunlight could remove more than 70.30% residues. There was a 63.90-97.14% reduction after steaming, with processing time extending, the removal rates increased especially for lower initial residue level samples. The residue was almost completely removed by frying combined with microwave heating. Furthermore, boiling the mushrooms reduced the residue in the mushroom and no carbendazim residues were determined in the broth. PMID:27386113

  11. Interfacial residual thermal strain

    NASA Astrophysics Data System (ADS)

    Kasen, M.; Santoyo, R.

    A method has been developed for assessing the influence of polymer chemical composition and of processing parameters on the magnitude of residual stress developed in glass-fibre-reinforced composites subjected to various cure cycles and subsequently cooled to cryogenic temperatures. The test method was applied to nine resin types, including epoxy, vinyl ester, polyester, cyanate ester and phenolic formulations. Results suggest that polyester resin develops substantially less overall residual strain than do the other resin systems.

  12. Quantifying logging residue - before the fact

    SciTech Connect

    Bones, J.T.

    1982-06-01

    Tree biomass estimation, which is being integrated into the U.S. Forest Service Renewable Resources Evaluation Program, will give foresters the ability to estimate the amount of logging residues they might expect from harvested treetops and branches and residual rough, rotten, and small trees before the actual harvest. With planning, and increased demand for such timber products as pulpwood and fuelwood, product recovery could be increased by up to 43 percent in softwood stands and 99% in hardwoods. Recovery levels affect gross product receipts and site preparation costs. An example of product recovery and residue generation is presented for three harvesting options in Pennsylvania hardwood stands. Under the whole-tree harvesting option, 46% more product was recovered than in single product harvesting, and logging residue levels were reduced by 58%.

  13. Mapping crop Residue Cover and Soil Tillage Intensity Using Remote Sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Until recently crop residues were managed primarily to reduce soil erosion and increase soil organic carbon, but demands for biofuels may remove much of the residue. Current methods of measuring crop residue cover are inadequate for characterizing the temporal and spatial variability of crop residu...

  14. Cellulose microfibril crystallinity is reduced by mutating C-terminal transmembrane region residues CESA1{sup A903V} and CESA3{sup T942I} of cellulose synthase

    SciTech Connect

    Harris, Darby; Corbin, Kendall; Wang, Tuo; Gutierrez, Ryan; Bertolo, Ana; Petti, Caroalberto; Smilgies, Detlef-M; Estevez, Jose Manuel; Bonetta, Dario; Urbanowicz, Breeanna; Ehrhardt, David; Somerville, Chris; Rose, Jocelyn; Hong, Mei; DeBolt, Seth

    2012-01-08

    The mechanisms underlying the biosynthesis of cellulose in plants are complex and still poorly understood. A central question concerns the mechanism of microfibril structure and how this is linked to the catalytic polymerization action of cellulose synthase (CESA). Furthermore, it remains unclear whether modification of cellulose microfibril structure can be achieved genetically, which could be transformative in a bio-based economy. To explore these processes in planta, we developed a chemical genetic toolbox of pharmacological inhibitors and corresponding resistance-conferring point mutations in the C-terminal transmembrane domain region of CESA1{sup A903V} and CESA3{sup T942I} in Arabidopsis thaliana. Using {sup 13}C solid-state nuclear magnetic resonance spectroscopy and X-ray diffraction, we show that the cellulose microfibrils displayed reduced width and an additional cellulose C4 peak indicative of a degree of crystallinity that is intermediate between the surface and interior glucans of wild type, suggesting a difference in glucan chain association during microfibril formation. Consistent with measurements of lower microfibril crystallinity, cellulose extracts from mutated CESA1{sup A903V} and CESA3{sup T942I} displayed greater saccharification efficiency than wild type. Using live-cell imaging to track fluorescently labeled CESA, we found that these mutants show increased CESA velocities in the plasma membrane, an indication of increased polymerization rate. Collectively, these data suggest that CESA1{sup A903V} and CESA3{sup T942I} have modified microfibril structure in terms of crystallinity and suggest that in plants, as in bacteria, crystallization biophysically limits polymerization.

  15. Chemical Stabilization of Hanford Tank Residual Waste

    SciTech Connect

    Cantrell, Kirk J.; Um, Wooyong; Williams, Benjamin D.; Bowden, Mark E.; Gartman, Brandy N.; Lukens, Wayne W.; Buck, Edgar C.; Mausolf, Edward J.

    2014-03-01

    Three different chemical treatment methods were tested for their ability to stabilize residual waste from Hanford tank C-202 for reducing contaminant release (Tc, Cr, and U in particular). The three treatment methods tested were lime addition [Ca(OH)2], an in-situ Ceramicrete waste form based on chemically bonded phosphate ceramics, and a ferrous iron/goethite treatment. These approaches rely on formation of insoluble forms of the contaminants of concern (lime addition and ceramicrete) and chemical reduction followed by co-precipitation (ferrous iron/goethite incorporation treatment). The results have demonstrated that release of the three most significant mobile contaminants of concern from tank residual wastes can be dramatically reduced after treatment compared to contact with simulated grout porewater without treatment. For uranium, all three treatments methods reduced the leachable uranium concentrations by well over three orders of magnitude. In the case of uranium and technetium, released concentrations were well below their respective MCLs for the wastes tested. For tank C-202 residual waste, chromium release concentrations were above the MCL but were considerably reduced relative to untreated tank waste. This innovative approach has the potential to revolutionize Hanford’s tank retrieval process, by allowing larger volumes of residual waste to be left in tanks while providing an acceptably low level of risk with respect to contaminant release that is protective of the environment and human health. Such an approach could enable DOE to realize significant cost savings through streamlined retrieval and closure operations.

  16. Close proximity gunshot residues.

    PubMed

    Thornton, J I

    1986-04-01

    Intuitively, a hand held in close proximity to a firearm at the instant of discharge will intercept a significant amount of gunshot residue, even though the hand did not actually come into contact with the weapon. There is, however, little information specifically described in the forensic science literature concerning the residue levels which might be encountered in such an instance. The present work confirms that antimony levels consistent with an individual having fired or handled a firearm may be intercepted by a hand held in close proximity. PMID:3711843

  17. Axial residual stresses in boron fibers

    NASA Technical Reports Server (NTRS)

    Behrendt, D. R.

    1978-01-01

    The axial residual stress distribution as a function of radius was determined from the fiber surface to the core including the average residual stress in the core. Such measurements on boron on tungsten (B/W) fibers show that the residual stresses for 102, 142, 203, and 366 micron diameter fibers were similar, being compressive at the surface and changing monotonically to a region of tensile within the boron. At approximately 25 percent of the original radius, the stress reaches a maximum tensile stress of about 860 mn/sq.m and then decreases to a compressive stress near the tungsten boride core. Data were presented for 203 micron diameter B/W fibers that show annealing above 900 C reduces the residual stresses. A comparison between 102 micron diameter B/W and boron on carbon (b/C) shows that the residual stresses were similar in the outer regions of the fibers, but that large differences near and in the core were observed. The effects of these residual stresses on the fracture of boron fibers were discussed.

  18. Optimization of reaction conditions for enzymatic viscosity reduction and hydrolysis of wheat arabinoxylan in an industrial ethanol fermentation residue.

    PubMed

    Sørensen, Hanne R; Pedersen, Sven; Meyer, Anne S

    2006-01-01

    This study examined enzyme-catalyzed viscosity reduction and evaluated the effects of substrate dry matter concentration on enzymatic degradation of arabinoxylan in a fermentation residue, "vinasse", resulting from industrial ethanol manufacture on wheat. Enzymatic catalysis was accomplished with a 50:50 mixture of an enzyme preparation from Humicola insolens, Ultraflo L, and a cellulolytic enzyme preparation from Trichoderma reesei, Celluclast 1.5 L. This enzyme mixture was previously shown to exhibit a synergistic action on arabinoxylan degradation. The viscosity of vinasse decreased with increased enzyme dosage and treatment time at pH 5, 50 degrees C, 5 wt % vinasse dry matter. After 24 h of enzymatic treatment, 76-84%, 75-80%, and 43-47%, respectively, of the theoretically maximal arabinose, xylose, and glucose releases were achieved, indicating that the viscosity decrease was a result of enzyme-catalyzed hydrolysis of arabinoxylan, beta-glucan, and cellulose. In designed response surface experiments, the optimal enzyme reaction conditions with respect to pH and temperature of the vinasse, the vinasse supernatant (mainly soluble material), and the vinasse sediment (mainly insoluble substances) varied from pH 5.2-6.4 and 41-49 degrees C for arabinose release and from pH 4.9-5.3 and 42-46 degrees C for xylose release. Even though only limited hydrolysis of the arabinoxylan in the vinasse sediment fraction was obtained, the results indicated that the same enzyme activities acted on the arabinoxylan in the different vinasse fractions irrespective of the state of solubility of the substrate material. The levels of liberated arabinose and xylose increased with increased dry matter concentration during enzymatic hydrolysis in the vinasse and the vinasse supernatant, but at the same time, increased substrate dry matter concentrations gave corresponding linear decreases in the hydrolytic efficiency as evaluated from levels of monosaccharide release per weight unit dry

  19. Structure of ten free N-glycans in ripening tomato fruit. Arabinose is a constituent of a plant N-glycan.

    PubMed Central

    Priem, B; Gitti, R; Bush, C A; Gross, K C

    1993-01-01

    The concentration-dependent stimulatory and inhibitory effect of N-glycans on tomato (Lycopersicon esculentum Mill.) fruit ripening was recently reported (B. Priem and K.C. Gross [1992] Plant Physiol 98: 399-401). We report here the structure of 10 free N-glycans in mature green tomatoes. N-Glycans were purified from fruit pericarp by ethanolic extraction, desalting, concanavalin A-Sepharose chromatography, and amine-bonded silica high performance liquid chromatography. N-Glycan structures were determined using 500 MHz 1H-nuclear magnetic resonance spectroscopy, fast atom bombardment mass spectrometry, and glycosyl linkage methylation analysis by gas chromatography-mass spectrometry. A novel arabinosyl-containing N-glycan, Man alpha 1-->6(Ara alpha 1-->2)Man beta 1-->4GlcNAc beta 1-->4(Fuc alpha 1-->3)GlcNAc, was purified from a retarded concanavalin A fraction. The location of the arabinosyl residue was the same as the xylosyl residue in complex N-glycans. GlcNAc[5']Man3(Xyl)GlcNAc(Fuc)GlcNAc and GlcNAc[5']Man2GlcNAc(Fuc)GlcNAc were also purified from the weakly retained fraction. The oligomannosyl N-glycans Man5GlcNAc, Man6GlcNAc, Man7GlcNAc, and Man8GlcNAc were purified from a strongly retained concanavalin A fraction. The finding of free Man5GlcNAc in situ was important physiologically because previously we had described it as a promoter of tomato ripening when added exogenously. Mature green pericarp tissue contained more than 1 microgram of total free N-glycan/g fresh weight. Changes in N-glycan composition were determined during ripening by comparing glycosyl and glycosyl-linkage composition of oligosaccharidic extracts from fruit at different developmental stages. N-Glycans were present in pericarp tissue at all stages of development. However, the amount increased during ripening, as did the relative amount of xylosyl-containing N-glycans. PMID:8108510

  20. CROP-RESIDUE MANAGEMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our agricultural production system is under increasing pressure to provide low cost, high quality food, fiber and biofuels while maintaining and preserving the environment. Increased interest in crop residues for production system sustainability is related to the recognition that the soil, water and...

  1. Utilizing water treatment residuals to reduce phosphorus runoff from biosolids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Approximately 40% of biosolids (sewage sludge) produced in the U.S. are incinerated or landfilled rather than land applied due to concern over non-point source phosphorus (P) runoff. The objective of this study was to determine the impact of chemical amendments on water-extractable P (WEP) in appli...

  2. Reducing Phosphorus Runoff from Biosolids with Water Treatment Residuals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A large fraction of the biosolids produced in the U.S. are placed in landfills or incinerated to avoid potential water quality problems associated with non-point source phosphorus (P) runoff. The objective of this study was to determine the effect of various chemical amendments on P runoff from bi...

  3. Capturing residual soil nitrogen with winter cereal cover crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The wide-spread drought during the 2012 summer has resulted in reduced crop growth, poor yields, and an anticipated increase in residual nitrate (NO3) nitrogen (N) in the soil profile. This residual N can potentially increase NO3-N losses to ground and/or surface waters, as well as increase carry-ov...

  4. Corn cob residue carbon and nutrient dynamics during decomposition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cob fraction of corn (Zea mays L.) residue has characteristics that reduce concerns associated with residue removal making it a potential biofuel feedstock. The contribution the cob fraction makes to soil C and nutrient dynamics is unknown. A litterbag study was conducted in no-tillage plots und...

  5. Assessing crop residue cover as scene moisture conditions change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop residue or plant litter is the portion of a crop left in the field after harvest. Crop residues on the soil surface provide a first line of defense against water and wind erosion and reduce the amounts of soil, nutrients, and pesticides that reach streams and rivers. Thus, quantification of cro...

  6. Catalytic combustion with incompletely vaporized residual fuel

    NASA Technical Reports Server (NTRS)

    Rosfjord, T. J.

    1981-01-01

    Catalytic combustion of fuel lean mixtures of incompletely vaporized residual fuel and air was investigated. The 7.6 cm diameter, graded cell reactor was constructed from zirconia spinel substrate and catalyzed with a noble metal catalyst. Streams of luminous particles exited the rector as a result of fuel deposition and carbonization on the substrate. Similar results were obtained with blends of No. 6 and No. 2 oil. Blends of shale residual oil and No. 2 oil resulted in stable operation. In shale oil blends the combustor performance degraded with a reduced degree of fuel vaporization. In tests performed with No. 2 oil a similar effect was observed.

  7. Residual stresses in material processing

    SciTech Connect

    Kozaczek, K.J.; Watkins, T.R.; Hubbard, C.R.; Wang, Xun-Li; Spooner, S.

    1994-09-01

    Material manufacturing processes often introduce residual stresses into the product. The residual stresses affect the properties of the material and often are detrimental. Therefore, the distribution and magnitude of residual stresses in the final product are usually an important factor in manufacturing process optimization or component life prediction. The present paper briefly discusses the causes of residual stresses. It then adresses the direct, nondestructive methods of residual stress measurement by X-ray and neutron diffraction. Examples are presented to demonstrate the importance of residual stress measurement in machining and joining operations.

  8. Production, properties and specificity of a new bacterial L-fucose- and D-arabinose-binding lectin of the plant aggressive pathogen Ralstonia solanacearum, and its comparison to related plant and microbial lectins.

    PubMed

    Sudakevitz, Dvora; Imberty, Anne; Gilboa-Garber, Nechama

    2002-08-01

    The worldwide distributed plant aggressive pathogen Ralstonia solanacearum, which causes lethal wilt in many agricultural crops, produces a potent L-fucose-binding lectin (RSL) exhibiting sugar specificity similar to that of PA-IIL of the human aggressive opportunistic pathogen Pseudomonas aeruginosa. Both lectins show L-fucose > L-galactose > D-arabinose > D-mannose specificity, but the affinities of RSL to these sugars are substantially lower. Unlike Ulex europaeus anti-H lectin, but like PA-IIL and Aleuria aurantia lectin (AAL), RSL agglutinates H-positive human erythrocytes regardless of their type, O, A, B, or AB, and animal erythrocytes (papain-treated ones more strongly than untreated ones). It also interacts with H and Lewis chains in the saliva of "secretors" and "nonsecretors." RSL purification is easier than that of PA-IIL since R. solanacearum extracts do not contain a galactophilic PA-IL-like activity. Mass spectrometry and 35 N-terminal amino acid sequencing enabled identification of the RSL protein (subunit approximately 9.9 kDa, approximately 90 amino acids) in the complete genome sequence of this bacterium. Despite the greater phylogenetic proximity of R. solanacearum to P. aeruginosa, and the presence of a PA-IIL-like gene in its genome, the RSL structure is not related to that of PA-IIL, but to that of the fucose-binding lectin of the mushroom (fungus) Aleuria aurantia, which like the two bacteria is a soil inhabitant. PMID:12153735

  9. l-Arabinose Isomerase and d-Xylose Isomerase from Lactobacillus reuteri: Characterization, Coexpression in the Food Grade Host Lactobacillus plantarum, and Application in the Conversion of d-Galactose and d-Glucose

    PubMed Central

    2014-01-01

    The l-arabinose isomerase (l-AI) and the d-xylose isomerase (d-XI) encoding genes from Lactobacillus reuteri (DSMZ 17509) were cloned and overexpressed in Escherichia coli BL21 (DE3). The proteins were purified to homogeneity by one-step affinity chromatography and characterized biochemically. l-AI displayed maximum activity at 65 °C and pH 6.0, whereas d-XI showed maximum activity at 65 °C and pH 5.0. Both enzymes require divalent metal ions. The genes were also ligated into the inducible lactobacillal expression vectors pSIP409 and pSIP609, the latter containing a food grade auxotrophy marker instead of an antibiotic resistance marker, and the l-AI- and d-XI-encoding sequences/genes were coexpressed in the food grade host Lactobacillus plantarum. The recombinant enzymes were tested for applications in carbohydrate conversion reactions of industrial relevance. The purified l-AI converted d-galactose to d-tagatose with a maximum conversion rate of 35%, and the d-XI isomerized d-glucose to d-fructose with a maximum conversion rate of 48% at 60 °C. PMID:24443973

  10. SRC Residual fuel oils

    DOEpatents

    Tewari, Krishna C.; Foster, Edward P.

    1985-01-01

    Coal solids (SRC) and distillate oils are combined to afford single-phase blends of residual oils which have utility as fuel oils substitutes. The components are combined on the basis of their respective polarities, that is, on the basis of their heteroatom content, to assure complete solubilization of SRC. The resulting composition is a fuel oil blend which retains its stability and homogeneity over the long term.

  11. Residual Neuromuscular Blockade.

    PubMed

    Plummer-Roberts, Anna L; Trost, Christina; Collins, Shawn; Hewer, Ian

    2016-02-01

    This article provides an update on residual neuromuscular blockade for nurse anesthetists. The neuromuscular junction, pharmacology for producing and reversing neuromuscular blockade, monitoring sites and methods, and patient implications relating to incomplete reversal of neuromuscular blockade are reviewed. Overall recommendations include using multiple settings when employing a peripheral nerve stimulator for monitoring return of neuromuscular function and administering pharmacologic reversal when the train-of-four ratio is below 0.9. PMID:26939390

  12. Energy from rice residues

    SciTech Connect

    Mahin, D.B.

    1990-03-01

    Developing countries produce millions of tons of rice husks and straw as a byproduct of harvesting rice. Although some of these rice residues are used for fuel or other purposes, most are burned for disposal or just dumped. However, since the mid- 1980's, industrial plants for rice residue utilization have been installed in several countries and are planned in a number of others. The report provides information on systems to produce energy from rice residues that are commercially available in the United States, Europe, and various developing countries, with an emphasis on those currently used or sold on an international level. Specifically reviewed are the use of rice husks to produce: (1) industrial process heat either directly from furnaces or by generating low pressure steam in boilers; (2) mechanical and electrical power for rice milling via steam engine systems, steam turbine/generator systems, and gasifier/engine systems; and (3) electric power for the grid. The outlook for producing energy from rice straw is also assessed. In addition, the prospects for the use of energy from husks or straw in the processing of rice bran are reviewed.

  13. CHARACTERIZING RESIDUE TRANSFER EFFICIENCIES USING A FLUORESCENT IMAGING TECHNIQUE

    EPA Science Inventory

    To reduce the uncertainty associated with current estimates of children's exposure to pesticides by dermal contact and indirect ingestion, residue transfer data are required. Prior to conducting exhaustive studies, a screening study to identify the important parameters for chara...

  14. Sustainable System for Residual Hazards Management

    SciTech Connect

    Kevin M. Kostelnik; James H. Clarke; Jerry L. Harbour

    2004-06-01

    Hazardous, radioactive and other toxic substances have routinely been generated and subsequently disposed of in the shallow subsurface throughout the world. Many of today’s waste management techniques do not eliminate the problem, but rather only concentrate or contain the hazardous contaminants. Residual hazards result from the presence of hazardous and/or contaminated material that remains on-site following active operations or the completion of remedial actions. Residual hazards pose continued risk to humans and the environment and represent a significant and chronic problem that require continuous longterm management (i.e. >1000 years). To protect human health and safeguard the natural environment, a sustainable system is required for the proper management of residual hazards. A sustainable system for the management of residual hazards will require the integration of engineered, institutional and land-use controls to isolate residual contaminants and thus minimize the associated hazards. Engineered controls are physical modifications to the natural setting and ecosystem, including the site, facility, and/or the residual materials themselves, in order to reduce or eliminate the potential for exposure to contaminants of concern (COCs). Institutional controls are processes, instruments, and mechanisms designed to influence human behavior and activity. System failure can involve hazardous material escaping from the confinement because of system degradation (i.e., chronic or acute degradation) or by externalintrusion of the biosphere into the contaminated material because of the loss of institutional control. An ongoing analysis of contemporary and historic sites suggests that the significance of the loss of institutional controls is a critical pathway because decisions made during the operations/remedial action phase, as well as decisions made throughout the residual hazards management period, are key to the longterm success of the prescribed system. In fact

  15. Crop Residue Coverage Estimation Using ASTER Imagery

    NASA Astrophysics Data System (ADS)

    Lewis, D.; Yao, H.; Kincaid, R.

    2006-12-01

    Soil erosion and its related runoff is a serious problem in U.S. agriculture. USDA has classified 33 percent of U.S. agricultural land as being highly erodible. It is well recognized that residue coverage on the soil surface can reduce soil erosion. The National Food Security Act of 1985 requires that agricultural producers protect all highly erodible cropland from excessive erosion. The 2002 Farm Bill gave U.S. Department of Agriculture's (USDA) Natural Resource Conservation Service (NRCS) the authority to make a determination of compliance. NRCS is currently running several programs to implement conservation practices and to monitor compliance. To be in compliance, growers must keep crop residue cover more than 30 percent of the field. This requires field-level assessment. The NRCS does not have the resources to regularly survey every field. One potential approach for compliance decision making is using data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor onboard NASA's Terra satellite. ASTER data provides 15 bands of 15 meter visible/NIR (VNIR) and 30 meter SWIR resolution data. Both the spatial resolution and spectral wavelength range and resolution are suitable for field level residue cover estimation. The objective of this study was to explore the potential of using ASTER data for crop residue cover estimation. The results indicate that ASTER imagery has good capability to identify residue within the corn fields and moderate capability in soybean residue estimation. SWIR bands have the most promise in separating crop residue when compared to the VNIR bands. Satellite based remote sensing imagery could be a potential rapid decision making tool for NRCS's compliance programs.

  16. Mobility of organic carbon from incineration residues

    SciTech Connect

    Ecke, Holger Svensson, Malin

    2008-07-01

    Dissolved organic carbon (DOC) may affect the transport of pollutants from incineration residues when landfilled or used in geotechnical construction. The leaching of dissolved organic carbon (DOC) from municipal solid waste incineration (MSWI) bottom ash and air pollution control residue (APC) from the incineration of waste wood was investigated. Factors affecting the mobility of DOC were studied in a reduced 2{sup 6-1} experimental design. Controlled factors were treatment with ultrasonic radiation, full carbonation (addition of CO{sub 2} until the pH was stable for 2.5 h), liquid-to-solid (L/S) ratio, pH, leaching temperature and time. Full carbonation, pH and the L/S ratio were the main factors controlling the mobility of DOC in the bottom ash. Approximately 60 weight-% of the total organic carbon (TOC) in the bottom ash was available for leaching in aqueous solutions. The L/S ratio and pH mainly controlled the mobilization of DOC from the APC residue. About 93 weight-% of TOC in the APC residue was, however, not mobilized at all, which might be due to a high content of elemental carbon. Using the European standard EN 13 137 for determination of total organic carbon (TOC) in MSWI residues is inappropriate. The results might be biased due to elemental carbon. It is recommended to develop a TOC method distinguishing between organic and elemental carbon.

  17. Chemical stabilization of Hanford tank residual waste

    NASA Astrophysics Data System (ADS)

    Cantrell, Kirk J.; Um, Wooyong; Williams, Benjamin D.; Bowden, Mark E.; Gartman, Brandy; Lukens, Wayne W.; Buck, Edgar C.; Mausolf, Edward J.

    2014-03-01

    Three different chemical treatment methods were tested for their ability to stabilize residual waste from Hanford tank C-202 for reducing contaminant release (Tc, Cr, and U in particular). The three treatment methods tested were lime addition [Ca(OH)2], an in situ Ceramicrete waste form based on chemically bonded phosphate ceramics, and a ferrous iron/goethite treatment. These approaches rely on formation of insoluble forms of the contaminants of concern (lime addition and Ceramicrete) and chemical reduction followed by co-precipitation (ferrous iron/goethite incorporation treatment). The results have demonstrated that release of uranium from tank residual wastes can be dramatically reduced after treatment compared to contact with simulated grout porewater without treatment. All three treatments methods reduced the leachable uranium concentrations by well over three orders of magnitude. In the case of uranium and technetium, released concentrations were well below their respective Maximum Contaminant Levels (MCLs) for the wastes tested. For tank C-202 residual waste, chromium release concentrations were above the MCL but were considerably reduced relative to untreated tank waste.

  18. Reduced-Bandwidth Coding for Mobile Communication

    NASA Technical Reports Server (NTRS)

    Davarian, F.

    1986-01-01

    Fade-resistant mobile systems use power and spectrum efficiently. Transmission system employs tone-calibrated technique (TCT). Residual carrier used in technique to reduce fading-induced effects and coherently demodulate received signal. TCT potentially efficient in use of power and of frequency spectrum. Coding technique, intended for residual-carrier transmission system, alleviates fading and spectrum crowding that hamper mobile communications.

  19. Improved Remote Crop Residue Cover Estimation by Incorporation of Soil and Residue Information

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Modern agricultural practices are increasingly making use of conservation (reduced- and no-till) methods, in order to minimize soil erosion and increase soil organic carbon (SOC) content. These methods result in increased crop residue cover after planting when compared to conventional tillage metho...

  20. The residual caries dilemma.

    PubMed

    Weerheijm, K L; Groen, H J

    1999-12-01

    Restorative dentistry is based on the assumption that bacterial infection of demineralized dentine should prompt operative intervention. One of the concepts of practical dentistry is to create a favourable environment for caries arrest with minimal operative intervention. The progress of remaining primary caries is key to any discussion of this concept. This discussion is important for the atraumatic restorative treatment (ART) approach, since the removal of all carious dentine is sometimes difficult using hand instruments only. In this paper the results of possible measures to guard against the effects of residual carious and its consequences are reviewed, in order to obtain an impression of the justification for (in)complete excavation of occlusal dentinal caries. Three types of measure are considered: isolating the caries process from the oral environment, excavating the carious dentine, and using a cariostatic filling material. Each of these measures contributes to the arrest of the caries process. However, none of these measures can arrest this process by itself. A combination of all three seems necessary. It is concluded that although residual caries does not seem to be the criterion for rerestoration, one has to strive for as complete caries removal as possible. If this cannot be fulfilled the sealing capacities of the filling material seem to be more important than its cariostatic properties. PMID:10600078

  1. Reducing the atmospheric impact of wet slaking

    SciTech Connect

    B.D. Zubitskii; G.V. Ushakov; B.G. Tryasunov; A.G.Ushakov

    2009-05-15

    Means of reducing the atmospheric emissions due to the wet slaking of coke are considered. One option, investigated here, is to remove residual active silt and organic compounds from the biologically purified wastewater sent for slaking, by coagulation and flocculation.

  2. Impact of Corn Residue Removal on Crop and Soil Productivity

    NASA Astrophysics Data System (ADS)

    Johnson, J. M.; Wilhelm, W. W.; Hatfield, J. L.; Voorhees, W. B.; Linden, D.

    2003-12-01

    Over-reliance on imported fuels, increasing atmospheric levels of greenhouses and sustaining food production for a growing population are three of the most important problems facing society in the mid-term. The US Department of Energy and private enterprise are developing technology necessary to use high cellulose feedstock, such as crop residues, for ethanol production. Based on production levels, corn (Zea mays L.) residue has potential as a biofuel feedstock. Crop residues are a renewable and domestic fuel source, which can reduce the rate of fossil fuel use (both imported and domestic) and provide an additional farm commodity. Crop residues protect the soil from wind and water erosion, provide inputs to form soil organic matter (a critical component determining soil quality) and play a role in nutrient cycling. Crop residues impact radiation balance and energy fluxes and reduce evaporation. Therefore, the benefits of using crop residues as fuel, which removes crop residues from the field, must be balanced against negative environmental impacts (e.g. soil erosion), maintaining soil organic matter levels, and preserving or enhancing productivity. All ramifications of new management practices and crop uses must be explored and evaluated fully before an industry is established. There are limited numbers of long-term studies with soil and crop responses to residue removal that range from negative to negligible. The range of crop and soil responses to crop residue removal was attributed to interactions with climate, management and soil type. Within limits, corn residue can be harvested for ethanol production to provide a renewable, domestic source of energy feedstock that reduces greenhouse gases. Removal rates must vary based on regional yield, climatic conditions and cultural practices. Agronomists are challenged to develop a protocol (tool) for recommending maximum permissible removal rates that ensure sustained soil productivity.

  3. Recycling of auto shredder residue.

    PubMed

    Nourreddine, Menad

    2007-01-31

    Currently, about 75% of end-of-life vehicle's (ELV) total weight is recycled in EU countries. The remaining 25%, which is called auto shredder residues (ASR) or auto fluff, is disposed of as landfill because of its complexity. It is a major challenge to reduce this percentage of obsolete cars. The European draft directive states that by the year 2006, only 15% of the vehicle's weight can be disposed of at landfill sites and by 2015, this will be reduced to 5%. The draft directive states that a further 10% can be incinerated. The quantities of shredder fluff are likely to increase in the coming years. This is because of the growing number of cars being scrapped, coupled with the increase in the amount of plastics used in cars. In Sweden, some current projects are focusing on recycling of ASR material. In this paper some different alternatives for using this material are reported. The hypothetical injection of ASR into a blast furnace concentrating on ASR's effect to some blast furnace (BF) parameters has been completed using a blast furnace mass balance model. As a result, in principle, ASR can be used as reducing agent in the BF process if certain conditions are met. The particle size of ASR material must be controlled to ensure optimal gasification of the material in the raceway. Regarding the chemical composition of ASR, the non-ferrous content can affect the pig iron quality, which is difficult to rectify at a later point. The most attractive recycling alternative is to use the products obtained from pyrolysis of ASR in appropriate metallurgical processes. PMID:16600493

  4. Residue harvest effects on corn response to applied N and yield

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn (Zea mays L.) residue harvest is common in Nebraska, primarily for feeding of beef cattle. Applied N immobilization is expected to be less with residue harvest due to reduced microbial activity for digestion of high CN organic material. Residue reduction may affect subsequent crop yield and res...

  5. Residue harvest effects on irrigated, no-till corn yield and nitrogen response

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn (Zea mays L.) residue harvest is common in Nebraska, primarily for feeding of beef cattle. Applied N immobilization is expected to be less with residue harvest due to reduced microbial activity for digestion of high CN organic material. Residue reduction may affect subsequent crop yield and res...

  6. Sugarcane Post-Harvest Residue Management in the Temperate Climate of Louisiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Full retention of sugarcane (interspecific hybrids of Saccharum spp.) post-harvest residue often reduces subsequent ratoon crop yields in Louisiana. Experiments were conducted to investigate if residue management effects are consistent across ratoon crops, to determine if residue management by soil...

  7. Residual gas analyzer calibration

    NASA Technical Reports Server (NTRS)

    Lilienkamp, R. H.

    1972-01-01

    A technique which employs known gas mixtures to calibrate the residual gas analyzer (RGA) is described. The mass spectra from the RGA are recorded for each gas mixture. This mass spectra data and the mixture composition data each form a matrix. From the two matrices the calibration matrix may be computed. The matrix mathematics requires the number of calibration gas mixtures be equal to or greater than the number of gases included in the calibration. This technique was evaluated using a mathematical model of an RGA to generate the mass spectra. This model included shot noise errors in the mass spectra. Errors in the gas concentrations were also included in the valuation. The effects of these errors was studied by varying their magnitudes and comparing the resulting calibrations. Several methods of evaluating an actual calibration are presented. The effects of the number of gases in then, the composition of the calibration mixture, and the number of mixtures used are discussed.

  8. Residual stress alleviation of aircraft metal structures reinforced with filamentary composites

    NASA Technical Reports Server (NTRS)

    Kelly, J. B.; June, R. R.

    1973-01-01

    Methods to eliminate or reduce residual stresses in aircraft metal structures reinforced by filamentary composites are discussed. Residual stress level reductions were achieved by modifying the manufacturing procedures used during adhesive bonding. The residual stress alleviation techniques involved various forms of mechanical constraint which were applied to the components during bonding. Nine methods were evaluated, covering a wide range in complexity. All methods investigated during the program affected the residual stress level. In general, residual stresses were reduced by 70 percent or more from the stress level produced by conventional adhesive bonding procedures.

  9. Selenium speciation in flue desulfurization residues.

    PubMed

    Zhong, Liping; Cao, Yan; Li, Wenying; Xie, Kechang; Pan, Wei-Ping

    2011-01-01

    Flue gas from coal combustion contains significant amounts of volatile selenium (Se). The capture of Se in the flue gas desulfurization (FGD) scrubber unit has resulted in a generation of metal-laden residues. It is important to determine Se speciation to understand the environmental impact of its disposal. A simple method has been developed for selective inorganic Se(IV), Se(VI) and organic Se determination in the liquid-phase FGD residues by hydride generation atomic fluorescence spectrometry (AFS). It has been determined that Se(IV), Se(VI) and organic Se can be accurately determined with detection limits (DL) of 0.05, 0.06 and 0.06 microg/L, respectively. The accuracy of the proposed method was evaluated by analyzing the certified reference material, NIST CRM 1632c, and also by analyzing spiked tap-water samples. Analysis indicates that the concentration of Se is high in FGD liquid residues and primarily exists in a reduced state as selenite (Se(IV)). The toxicity of Se(IV) is the strongest of all Se species. Flue gas desulfurization residues pose a serious environmental risk. PMID:21476358

  10. Materials recovery from shredder residues

    SciTech Connect

    Daniels, E. J.; Jody, B. J.; Pomykala, J., Jr.

    2000-07-24

    Each year, about five (5) million ton of shredder residues are landfilled in the US. Similar quantities are landfilled in Europe and the Pacific Rim. Landfilling of these residues results in a cost to the existing recycling industry and also represents a loss of material resources that are otherwise recyclable. In this paper, the authors outline the resources recoverable from typical shredder residues and describe technology that they have developed to recover these resources.

  11. Laundering as decontamination of apparel fabrics: residues of pesticides from six chemical classes.

    PubMed

    Nelson, C; Laughlin, J; Kim, C; Rigakis, K; Raheel, M; Scholten, L

    1992-07-01

    Research on reducing the level of pesticide residue on a textile substrate has examined many variables under many different conditions. This study controlled fiber type and the use of prewash product in an examination of residue levels for a number of pesticides in different pesticide classes. For all pesticides examined, the use of prewash lowered pesticide residues regardless of fiber type. Differences in pesticide residue level attributable to fiber type were not consistent. PMID:1637202

  12. Residual stresses in darrieus vertical axis wind turbine blades

    SciTech Connect

    Veers, P.

    1981-04-01

    A numerical package called RESID has been assembled to calculate the residual stresses in VAWT blades induced during cold forming. Using a strength of materials - elementary beam theory approach, RESID models the material response with a bilinear stress-strain curve, and the cross-sectional geometry with an array of area increments. Through an iterative solution procedure residual stresses are predicted for a specified final radius of curvature or applied bending moment. RESID results are compared to theoretical solutions for simple geometries and with MARC Finite element results for VAWT blade geometries. Calculating residual stress levels, determining acceptable residual stress levels, and a method of reducing residual stresses are discussed. A complete listing and sample run are included in the appendicies.

  13. Glove accumulation of pesticide residues for strawberry harvester exposure assessment.

    PubMed

    Li, Yanhong; Chen, Li; Chen, Zhenshan; Coehlo, Joe; Cui, Li; Liu, Yu; Lopez, Terry; Sankaran, Gayatri; Vega, Helen; Krieger, Robert

    2011-06-01

    We investigated the accumulation of pesticide residues on rubber latex gloves that are used by strawberry harvesters to protect their skin, reduce pesticide exposure and promote food safety. Gloves accumulated residues of 16 active ingredients including azoxystrobin, bifenthrin, boscalid, captan, cyprodinil, fenhexamid, fenpropathrin, fludioxonil, hexythiazox, malathion, methomyl, naled, propiconazole, pyraclostrobin, quinoline, and quinoxyfen at different times. Glove residue accumulation (t(½) 2.8-3.7 d) was very similar to the dissipation of DFRs (t(½) 2.1-3.0 d) during the first 3 weeks after malathion applications. Dermal malathion dose was 0.2 mg/kg at the preharvest interval and declined to trace levels during the following 3 months. Glove accumulation of malathion indicated trace surface residue availability and was used to assess the relationship between dislodgable foliar residues and potential hand exposure. PMID:21503692

  14. Microwave emission and crop residues

    NASA Technical Reports Server (NTRS)

    Jackson, Thomas J.; O'Neill, Peggy E.

    1991-01-01

    A series of controlled experiments were conducted to determine the significance of crop residues or stubble in estimating the emission of the underlying soil. Observations using truck-mounted L and C band passive microwave radiometers showed that for dry wheat and soybeans the dry residue caused negligible attenuation of the background emission. Green residues, with water contents typical of standing crops, did have a significant effect on the background emission. Results for these green residues also indicated that extremes in plant structure, as created using parallel and perpendicular stalk orientations, can cause very large differences in the degree of attenuation.

  15. Reducing Dropouts.

    ERIC Educational Resources Information Center

    Timpane, Michael; And Others

    A group of three conference papers, all addressing the subject of effective programs to decrease the number of school dropouts, is presented in this document. The first paper, "Systemic Approaches to Reducing Dropouts" (Michael Timpane), asserts that dropping out is a symptom of failures in the social, economic, and educational systems. Dropping…

  16. Costs for alternative grain-residue-collection systems

    NASA Astrophysics Data System (ADS)

    Flaim, S. J.; Neenan, B.; Dauve, J.; Mapp, H. P., Jr.

    1981-06-01

    The costs for systems for corn and soybean production in Iowa are examined. All machinery field operations, fuel, other inputs, and labor requirements are identified for the base case with no residue harvest, and for residue harvest by stacks and large round bales, with the owner's equipment and for custom harvest. These five cases were developed for corn and soybeans for conventional and reduced tillage practices. Harvesting alternatives are compared on the basis of costs, fuel input requirements, and gross energy balances of residues collected less energy inputs. The cost of collecting corn and soybean residues varies widely over the collection and tillage systems examined. Other effects constant, the reduced tillage practice leads to a lower cost of harvest than conventional tillage, and stacks are always cheaper than large round bales; however, the former difference is greater than the latter.

  17. On tide-induced lagrangian residual current and residual transport: 1. Lagrangian residual current

    USGS Publications Warehouse

    Feng, Shizuo; Cheng, Ralph T.; Pangen, Xi

    1986-01-01

    Residual currents in tidal estuaries and coastal embayments have been recognized as fundamental factors which affect the long-term transport processes. It has been pointed out by previous studies that it is more relevant to use a Lagrangian mean velocity than an Eulerian mean velocity to determine the movements of water masses. Under weakly nonlinear approximation, the parameter k, which is the ratio of the net displacement of a labeled water mass in one tidal cycle to the tidal excursion, is assumed to be small. Solutions for tides, tidal current, and residual current have been considered for two-dimensional, barotropic estuaries and coastal seas. Particular attention has been paid to the distinction between the Lagrangian and Eulerian residual currents. When k is small, the first-order Lagrangian residual is shown to be the sum of the Eulerian residual current and the Stokes drift. The Lagrangian residual drift velocity or the second-order Lagrangian residual current has been shown to be dependent on the phase of tidal current. The Lagrangian drift velocity is induced by nonlinear interactions between tides, tidal currents, and the first-order residual currents, and it takes the form of an ellipse on a hodograph plane. Several examples are given to further demonstrate the unique properties of the Lagrangian residual current.

  18. A manual for implementing residual radioactive material guidelines

    SciTech Connect

    Gilbert, T.L.; Yu, C.; Yuan, Y.C.; Zielen, A.J.; Jusko, M.J.; Wallo, A. III

    1989-06-01

    This manual presents information for implementing US Department of Energy (DOE) guidelines for residual radioactive material at sites identified by the Formerly Utilized Sites Remedial Action Program (FUSRAP) and the Surplus Facilities Management Program (SFMP). It describes the analysis and models used to derive site-specific guidelines for allowable residual concentrations of radionuclides in soil and the design and use of the RESRAD computer code for calculating guideline values. It also describes procedures for implementing DOE policy for reducing residual radioactivity to levels that are as low as reasonably achievable. 36 refs., 16 figs, 22 tabs.

  19. Residual Field Correction of Pulsed Bending Magnet

    NASA Astrophysics Data System (ADS)

    Takano, Junpei; Igarashi, Susumu; Kamikubota, Norihiko; Meigo, Shin-ichiro; Sato, Kenichi; Shirakata, Masashi; Yamada, Shuei

    The Japan Proton Accelerator Research Complex (J-PARC) has an accelerator chain, Linac, Rapid Cycling Synchrotron (RCS), and Main Ring (MR). The RCS accelerates the proton beam up to 3 GeV every 40 msec. After the beam is extracted from the RCS, it is delivered to a beam transport line, which is 3NBT for the Material and Life Science Experimental Facility (MLF). Some bunches of the proton beam are bended from the 3NBT to another beam transport line, which is 3-50BT for the MR, by using a pulsed bending magnet (PB) [1]. However, the beam orbit in the 3NBT is kicked by the residual magnetic field of the PB. In order to correct the residual magnetic field, additional coils had been wound on the PB poles. As a result of scanning the current pattern of the correction coils, the orbit distortion in the 3NBT has been reduced.

  20. Sugar composition of the pectic polysaccharides of charophytes, the closest algal relatives of land-plants: presence of 3-O-methyl-d-galactose residues

    PubMed Central

    O’Rourke, Christina; Gregson, Timothy; Murray, Lorna; Sadler, Ian H.; Fry, Stephen C.

    2015-01-01

    Background and Aims During evolution, plants have acquired and/or lost diverse sugar residues as cell-wall constituents. Of particular interest are primordial cell-wall features that existed, and in some cases abruptly changed, during the momentous step whereby land-plants arose from charophytic algal ancestors. Methods Polysaccharides were extracted from four charophyte orders [Chlorokybales (Chlorokybus atmophyticus), Klebsormidiales (Klebsormidium fluitans, K. subtile), Charales (Chara vulgaris, Nitella flexilis), Coleochaetales (Coleochaete scutata)] and an early-diverging land-plant (Anthoceros agrestis). ‘Pectins’ and ‘hemicelluloses’, operationally defined as extractable in oxalate (100 °C) and 6 m NaOH (37 °C), respectively, were acid- or Driselase-hydrolysed, and the monosaccharides analysed chromatographically. One unusual monosaccharide, ‘U’, was characterized by 1H/13C-nuclear magnetic resonance spectroscopy and also enzymically. Key Results ‘U’ was identified as 3-O-methyl-d-galactose (3-MeGal). All pectins, except in Klebsormidium, contained acid- and Driselase-releasable galacturonate, suggesting homogalacturonan. All pectins, without exception, released rhamnose and galactose on acid hydrolysis; however, only in ‘higher’ charophytes (Charales, Coleochaetales) and Anthoceros were these sugars also efficiently released by Driselase, suggesting rhamnogalacturonan-I. Pectins of ‘higher’ charophytes, especially Chara, contained little arabinose, instead possessing 3-MeGal. Anthoceros hemicelluloses were rich in glucose, xylose, galactose and arabinose (suggesting xyloglucan and arabinoxylan), none of which was consistently present in charophyte hemicelluloses. Conclusions Homogalacturonan is an ancient streptophyte feature, albeit secondarily lost in Klebsormidium. When conquering the land, the first embryophytes already possessed rhamnogalacturonan-I. In contrast, charophyte and land-plant hemicelluloses differ

  1. Sugarcane rice residue biochars and their applications

    NASA Astrophysics Data System (ADS)

    Wang, J. J.

    2014-12-01

    production, and reduced greenhouse gas emission. Overall, the conversion of sugarcane harvest residue to biochar as soil amendment improves sugarcane production for both agronomic and environmental benefits. Sugarcane residue biochar also showed the potential of other environmental use for remediation of petroleum hydrocarbons.

  2. Impact of corn residue on yield of cool-season crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synergy between dry pea and corn can reduce the density of corn needed for optimum yield. Lower crop density may accrue an additional benefit, as after-harvest residues of corn lying on the soil surface can reduce yield of crops planted the next year. This study evaluated impact of corn residue lev...

  3. Improved Remotely-Sensed Estimates of Crop Residue Cover by Incorporating Soils Information.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conservation tillage (CT) methods, which include reduced- and no-till methods, leave substantial quantities of crop residues on the soil surface. These crop residues act as a barrier to wind and water to reduce soil erosion and evaporation. Long-term CT also increases soil organic carbon (SOC) cont...

  4. Measurement and correlation of conditions for entrapment and mobilization of residual oil. First annual report

    SciTech Connect

    Morrow, N.R.

    1982-09-01

    Substantial progress has been made in four major task areas. The first task is to establish the limits of reliability of laboratory waterflooding as an evaluation tool. Wettability is identified as a key variable. Work is being extended to wetting properties of crude oils and core flooding. The second task concerns the effects of high capillary number flows on trapping phenomena and residual oil saturation. Correlations of capillary number and relative permeability behavior at reduced residual saturations have been developed for displacement in sandstones. The third task deals with mechanisms of mobilization and entrapment of residual oil. Detailed accounts have recently been presented of work on relative permeability at reduced residual oil saturations and for factors which affect the magnitude and distribution of residual oil. Work on the fourth task concerns the detailed structure of residual oil. The size distribution of residual oil blobs, obtained under various displacement conditions, is being measured by various size-analysis methods.

  5. Universality in Protein Residue Networks

    PubMed Central

    Estrada, Ernesto

    2010-01-01

    Abstract Residue networks representing 595 nonhomologous proteins are studied. These networks exhibit universal topological characteristics as they belong to the topological class of modular networks formed by several highly interconnected clusters separated by topological cavities. There are some networks that tend to deviate from this universality. These networks represent small-size proteins having <200 residues. This article explains such differences in terms of the domain structure of these proteins. On the other hand, the topological cavities characterizing proteins residue networks match very well with protein binding sites. This study investigates the effect of the cutoff value used in building the residue network. For small cutoff values, <5 Å, the cavities found are very large corresponding almost to the whole protein surface. On the contrary, for large cutoff value, >10.0 Å, only very large cavities are detected and the networks look very homogeneous. These findings are useful for practical purposes as well as for identifying protein-like complex networks. Finally, this article shows that the main topological class of residue networks is not reproduced by random networks growing according to Erdös-Rényi model or the preferential attachment method of Barabási-Albert. However, the Watts-Strogatz model reproduces very well the topological class as well as other topological properties of residue network. A more biologically appealing modification of the Watts-Strogatz model to describe residue networks is proposed. PMID:20197043

  6. Noninvasive in vivo determination of residual strains and stresses.

    PubMed

    Donmazov, Samir; Piskin, Senol; Pekkan, Kerem

    2015-06-01

    Vascular growth and remodeling during embryonic development are associated with blood flow and pressure induced stress distribution, in which residual strains and stresses play a central role. Residual strains are typically measured by performing in vitro tests on the excised vascular tissue. In this paper, we investigated the possibility of estimating residual strains and stresses using physiological pressure-radius data obtained through in vivo noninvasive measurement techniques, such as optical coherence tomography or ultrasound modalities. This analytical approach first tested with in vitro results using experimental data sets for three different arteries such as rabbit carotid artery, rabbit thoracic artery, and human carotid artery based on Fung's pseudostrain energy function and Delfino's exponential strain energy function (SEF). We also examined residual strains and stresses in the human swine iliac artery using the in vivo experimental ultrasound data sets corresponding to the systolic-to-diastolic region only. This allowed computation of the in vivo residual stress information for loading and unloading states separately. Residual strain parameters as well as the material parameters were successfully computed with high accuracy, where the relative errors are introduced in the range of 0-7.5%. Corresponding residual stress distributions demonstrated global errors all in acceptable ranges. A slight discrepancy was observed in the computed reduced axial force. Results of computations performed based on in vivo experimental data obtained from loading and unloading states of the artery exhibited alterations in material properties and residual strain parameters as well. Emerging noninvasive measurement techniques combined with the present analytical approach can be used to estimate residual strains and stresses in vascular tissues as a precursor for growth estimates. This approach is also validated with a finite element model of a general two-layered artery

  7. Safety assessment of drug residues

    SciTech Connect

    Jackson, B.A.

    1980-05-15

    The safety assessment of drug residues is part of the process for defining the conditions for the safe use of drugs in food-producing animals. The information needed to assess the safety of drug residues is provided by chemical and toxicity tests. Toxicity tests are conducted to identify the type of effect produced and to determine the exposure concentrations that would be expected not to produce the effect. These tests include acute, subacute, and chronic toxicity tests, as well as reproduction studies and other special tests. The results are used to find an acceptable daily intake for drug residues that can be used to set a tolerance.

  8. Sludge displacement verification for reducing grout report

    SciTech Connect

    Caldwell, T.B.; Langton, C.A.

    1997-04-10

    To support the closure of HLW tanks at SRS, a reducing grout was developed that is formulated to reduce the mobility of radionuclides left in each tank. During non-radioactive flow tests of the grout, it was discovered that, in addition to its desired properties, the grout has the ability to move residual waste a considerable distance across the tank floor.

  9. Fasting, but Not Aging, Dramatically Alters the Redox Status of Cysteine Residues on Proteins in Drosophila melanogaster.

    PubMed

    Menger, Katja E; James, Andrew M; Cochemé, Helena M; Harbour, Michael E; Chouchani, Edward T; Ding, Shujing; Fearnley, Ian M; Partridge, Linda; Murphy, Michael P

    2015-06-30

    Altering the redox state of cysteine residues on protein surfaces is an important response to environmental challenges. Although aging and fasting alter many redox processes, the role of cysteine residues is uncertain. To address this, we used a redox proteomic technique, oxidative isotope-coded affinity tags (OxICAT), to assess cysteine-residue redox changes in Drosophila melanogaster during aging and fasting. This approach enabled us to simultaneously identify and quantify the redox state of several hundred cysteine residues in vivo. Cysteine residues within young flies had a bimodal distribution with peaks at ∼10% and ∼85% reversibly oxidized. Surprisingly, these cysteine residues did not become more oxidized with age. In contrast, 24 hr of fasting dramatically oxidized cysteine residues that were reduced under fed conditions while also reducing cysteine residues that were initially oxidized. We conclude that fasting, but not aging, dramatically alters cysteine-residue redox status in D. melanogaster. PMID:26095360

  10. Residual tembotrione and atrazine in carrot.

    PubMed

    Bontempo, Amanda F; Carneiro, Gabriella D P; Guimarães, Fernanda A R; Dos Reis, Marcelo R; Silva, Daniel V; Rocha, Bruno H; Souza, Matheus F; Sediyama, Tocio

    2016-07-01

    Carrot (Daucus carota L.) is a vegetable crop that is grown throughout the year across various regions of Brazil in rotation or in succession to other cultures. Herbicide residual effect has emerged as a concern, because of the possibility of carryover. Thus, the objective of this study was to evaluate the effect of tembotrione and atrazine residues - in mixture and isolated - on carrot planted in succession to corn. The experiment was designed in randomized blocks with five replications. Treatments consisted of tembotrione (50.4 g ha(-1)), tembotrione (100.8 g ha(-1)), tembotrione + atrazine (50.4 g ha(-1)+ 2 L ha(-1)), tembotrione + atrazine (100.8 g ha(-1)+ 2 L ha(-1)), and atrazine (2.00 L ha(-1)) applied eight months before carrot seeding, plus a control treatment with no herbicide application. Investigated variables were shoot dry mass, productivity, and classification of carrot roots. The presence of atrazine and tembotrione decreased dry mass in the area, and only tembotrione reduced total root productivity. Thus, there is a carryover effect to tembotrione application that reduces the dry matter accumulation of shoot and total productivity, and an atrazine + tembotrione (100.8 g ha(-1)) mixture reduces the total productivity after application of these herbicides to soil. PMID:27052932

  11. Demonstration of catalytic combustion with residual fuel

    NASA Technical Reports Server (NTRS)

    Dodds, W. J.; Ekstedt, E. E.

    1981-01-01

    An experimental program was conducted to demonstrate catalytic combustion of a residual fuel oil. Three catalytic reactors, including a baseline configuration and two backup configurations based on baseline test results, were operated on No. 6 fuel oil. All reactors were multielement configurations consisting of ceramic honeycomb catalyzed with palladium on stabilized alumina. Stable operation on residual oil was demonstrated with the baseline configuration at a reactor inlet temperature of about 825 K (1025 F). At low inlet temperature, operation was precluded by apparent plugging of the catalytic reactor with residual oil. Reduced plugging tendency was demonstrated in the backup reactors by increasing the size of the catalyst channels at the reactor inlet, but plugging still occurred at inlet temperature below 725 K (845 F). Operation at the original design inlet temperature of 589 K (600 F) could not be demonstrated. Combustion efficiency above 99.5% was obtained with less than 5% reactor pressure drop. Thermally formed NO sub x levels were very low (less than 0.5 g NO2/kg fuel) but nearly 100% conversion of fuel-bound nitrogen to NO sub x was observed.

  12. Ideal architecture of residue packing and its observation in protein structures.

    PubMed Central

    Raghunathan, G.; Jernigan, R. L.

    1997-01-01

    A simple model of sphere packing has been investigated as an ideal model for long-range interactions for the packing of non-bonded residues in protein structures. By superposing all residues, the geometry of packing around a central residue is investigated. It is found that all residues conform almost perfectly to this lattice model for sphere packing when a radius of 6.5 A is used to define non-bonded (virtual) interacting residues. Side-chain positions with respect to sequential backbone segments are relatively regular as well. This lattice can readily be used in conformation simulations to reduce the conformational space. PMID:9336831

  13. Effects of Crop Residue on the Persistence of Steinernema carpocapsae

    PubMed Central

    Shapiro, David I.; Obrycki, John J.; Lewis, Leslie C.; Jackson, Jan J.

    1999-01-01

    We determined the effects of crop residue on the persistence of an entomopathogenic nematode, Steinernema carpocapsae. During 2 consecutive years, nematodes were applied at rates of 2.5 × 10₄ and 1.0 × 10⁵ infective juveniles/m² to small field plots planted with corn. Nematode persistence was monitored by exposing Galleria mellonella larvae to soil samples from plots with and without crop residue (approximately 75% coverage of soybean stubble). Persistence of S. carpocapsae was significantly greater in crop residue plots than in plots without residue. In crop residue plots that received the higher rate of nematode application, larval mortality did not significantly decrease during the study period (3 to 5 days) and remained above 85%. In nematode-treated plots without crop residue, however, larval mortality fell from over 96% to below 11% and 35% in the first and second trials, respectively. The increased crop residue may have benefited nematode persistence through protection from desiccation or ultraviolet light. We conclude that increased ground cover in cropping systems (e.g., due to reduced tillage) may lead to increased insect pest suppression with entomopathogenic nematodes. PMID:19270924

  14. Americium recovery from reduction residues

    DOEpatents

    Conner, W.V.; Proctor, S.G.

    1973-12-25

    A process for separation and recovery of americium values from container or bomb'' reduction residues comprising dissolving the residues in a suitable acid, adjusting the hydrogen ion concentration to a desired level by adding a base, precipitating the americium as americium oxalate by adding oxalic acid, digesting the solution, separating the precipitate, and thereafter calcining the americium oxalate precipitate to form americium oxide. (Official Gazette)

  15. Residual Resistance Data from Cavity Production Projects at Jefferson Lab

    SciTech Connect

    Gianluigi Ciovati, Rongli Geng, John Mammosser, Jeffrey Saunders

    2010-11-01

    A fundamental limitation towards achieving high quality factors in superconducting radio-frequency cavities is the so-called residual resistance. Understanding and controlling the residual resistance has important implications towards improving the efficiency and reduce the operating cost of continuous wave superconducting linear accelerators. In this contribution we will report on the residual resistance values obtained from measurements of the quality factor of a large set of cavities, with resonant frequency between 805 MHz and 1.5 GHz, all of them processed and tested at Jefferson Lab. Surface treatments included both buffered chemical polishing and electropolishing. The results indicate an approximate value of the residual resistance of about 7-10 n Omega.

  16. Process-dependent residual trapping of CO2 in sandstone

    NASA Astrophysics Data System (ADS)

    Zuo, Lin; Benson, Sally M.

    2014-04-01

    This paper demonstrates that the nature and extent of residual CO2 trapping depend on the process by which the CO2 phase is introduced into the rock. We compare residual trapping of CO2 in Berea Sandstone by imbibing water into a core containing either exsolved CO2 or CO2 introduced by drainage. X-ray computed tomography measurements are used to map the spatial distribution of CO2 preimbibition and postimbibition. Unlike during drainage where the CO2 distribution is strongly influenced by the heterogeneity of the rock, the distribution of exsolved CO2 is comparatively uniform. Postimbibition, the CO2 distribution retained the essential features for both the exsolved and drainage cases, but twice as much residual trapping is observed for exsolved CO2 even with similar preimbibition gas saturations. Residually trapped exsolved gas also disproportionately reduced water relative permeability. Development of process-dependent parameterization will help better manage subsurface flow processes and unlock benefits from gas exsolution.

  17. Residual stress measurements of tension leg platform tendon welds

    SciTech Connect

    Kim, D.S.; Smith, J.D.

    1994-12-31

    Results of fatigue test of prototype welded tendons showed that fatigue life was greatly reduced for the weld repaired joint. Since tensile residual stresses near the fusion boundary were suspected to cause the fatigue life reduction, these residual stresses were measured. Residual stresses of girth welded tendon pipes for a tension leg platform (TLP) were obtained for various fabrication conditions. The stresses were measured experimentally using the blind hole drilling (BHD) technique, X-ray diffraction (XRD) technique and Barkhausen Noise (BHN) method. The results of these measurements illustrate the reliability of each measurement technique. Effects of joint configuration, weld repair, weld cap grinding, and pre-fatigue test on residual stresses were discussed.

  18. DISSOLUTION OF NEPTUNIUM OXIDE RESIDUES

    SciTech Connect

    Kyser, E

    2009-01-12

    This report describes the development of a dissolution flowsheet for neptunium (Np) oxide (NpO{sub 2}) residues (i.e., various NpO{sub 2} sources, HB-Line glovebox sweepings, and Savannah River National Laboratory (SRNL) thermogravimetric analysis samples). Samples of each type of materials proposed for processing were dissolved in a closed laboratory apparatus and the rate and total quantity of off-gas were measured. Samples of the off-gas were also analyzed. The quantity and type of solids remaining (when visible) were determined after post-dissolution filtration of the solution. Recommended conditions for dissolution of the NpO{sub 2} residues are: Solution Matrix and Loading: {approx}50 g Np/L (750 g Np in 15 L of dissolver solution), using 8 M nitric acid (HNO{sub 3}), 0.025 M potassium fluoride (KF) at greater than 100 C for at least 3 hours. Off-gas: Analysis of the off-gas indicated nitric oxide (NO), nitrogen dioxide (NO{sub 2}) and nitrous oxide (N{sub 2}O) as the only identified components. No hydrogen (H{sub 2}) was detected. The molar ratio of off-gas produced per mole of Np dissolved ranged from 0.25 to 0.4 moles of gas per mole of Np dissolved. A peak off-gas rate of {approx}0.1 scfm/kg bulk oxide was observed. Residual Solids: Pure NpO{sub 2} dissolved with little or no residue with the proposed flowsheet but the NpCo and both sweepings samples left visible solid residue after dissolution. For the NpCo and Part II Sweepings samples the residue amounted to {approx}1% of the initial material, but for the Part I Sweepings sample, the residue amounted to {approx}8 % of the initial material. These residues contained primarily aluminum (Al) and silicon (Si) compounds that did not completely dissolve under the flowsheet conditions. The residues from both sweepings samples contained minor amounts of plutonium (Pu) particles. Overall, the undissolved Np and Pu particles in the residues were a very small fraction of the total solids.

  19. Residual stresses in welded plates

    NASA Technical Reports Server (NTRS)

    Bernstein, Edward L.

    1994-01-01

    The purpose of this project was to develop a simple model which could be used to study residual stress. The mechanism that results in residual stresses in the welding process starts with the deposition of molten weld metal which heats the immediately adjacent material. After solidification of weld material, normal thermal shrinkage is resisted by the adjacent, cooler material. When the thermal strain exceeds the elastic strain corresponding to the yield point stress, the stress level is limited by this value, which decreases with increasing temperature. Cooling then causes elastic unloading which is restrained by the adjoining material. Permanent plastic strain occurs, and tension is caused in the region immediately adjacent to the weld material. Compression arises in the metal farther from the weld in order to maintain overall static equilibrium. Subsequent repair welds may add to the level of residual stresses. The level of residual stress is related to the onset of fracture during welding. Thus, it is of great importance to be able to predict the level of residual stresses remaining after a weld procedure, and to determine the factors, such as weld speed, temperature, direction, and number of passes, which may affect the magnitude of remaining residual stress. It was hoped to use traditional analytical modeling techniques so that it would be easier to comprehend the effect of these variables on the resulting stress. This approach was chosen in place of finite element methods so as to facilitate the understanding of the physical processes. The accuracy of the results was checked with some existing experimental studies giving residual stress levels found from x-ray diffraction measurements.

  20. Residual deformations in ocular tissues

    PubMed Central

    Wang, Ruoya; Raykin, Julia; Gleason, Rudolph L.; Ethier, C. Ross

    2015-01-01

    Residual deformations strongly influence the local biomechanical environment in a number of connective tissues. The sclera is known to be biomechanically important in healthy and diseased eyes, such as in glaucoma. Here, we study the residual deformations of the sclera, as well as the adjacent choroid and retina. Using freshly harvested porcine eyes, we developed two approaches of quantifying residual deformations in the spherically shaped tissues of interest. The first consisted of punching discs from the posterior wall of the eye and quantifying the changes in the area and eccentricity of these samples. The second consisted of cutting a ring from the equatorial sclera and making stress-relieving cuts in it. Measurements of curvature were made before and after the stress-relieving cuts. Using the first approach, we observed a 42% areal contraction of the choroid, but only modest contractions of the sclera and retina. The observed contractions were asymmetric. In the second approach, we observed an opening of the scleral rings (approx. 10% decrease in curvature). We conclude that residual bending deformations are present in the sclera, which we speculate may be due to radially heterogeneous growth and remodelling of the tissue during normal development. Further, residual areal deformations present in the choroid may be due to the network of elastic fibres in this tissue and residual deformations in the constituent vascular bed. Future studies of ocular biomechanics should attempt to include effects of these residual deformations into mechanical models in order to gain a better understanding of the biomechanics of the ocular wall. PMID:25740853

  1. Recycling crop residues for use in recirculating hydroponic crop production

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Garland, J. L.; Sager, J. C.

    1996-01-01

    As part of bioregenerative life support feasibility testing by NASA, crop residues are being used to resupply elemental nutrients to recirculating hydroponic crop production systems. Methods for recovering nutrients from crop residues have evolved from water soaking (leaching) to rapid aerobic bioreactor processing. Leaching residues recovered the majority of elements but it also recovered significant amounts of soluble organics. The high organic content of leachates was detrimental to plant growth. Aerobic bioreactor processing reduced the organic content ten-fold, which reduced or eliminated phytotoxic effects. Wheat and potato production studies were successful using effluents from reactors having with 8- to 1-day retention times. Aerobic bioreactor effluents supplied at least half of the crops elemental mass needs in these studies. Descriptions of leachate and effluent mineral content, biomass productivity, microbial activity, and nutrient budgets for potato and wheat are presented.

  2. Field emitter based extractor gauges and residual gas analyzers

    SciTech Connect

    Changkun Dong; G. Rao Myneni

    1999-04-01

    Attempts at using the Spindt-type molybdenum field emitter arrays in the extractor gauges and a residual gas analyzer are presented in this article. The sensitivity of the fuel emitter gauge is as high as 11 Torr{sup -1}. The departure from linearity of the pressure versus ion current measurements did not exceed 10% over the pressure range of 10{sup -10} - 10{sup -6} Torr. Stable sensitivities for nitrogen, helium, and hydrogen were achieved below 10{sup -7} Torr with the field emitter residual gas analyzer. The slightly reduced emission current and sensitivity, after long-term operation, are of concern and need to be addressed. Residual gas spectra indicate that when using field emitters, the electron stimulated desorption ions (O{sup +}, F{sup +}, and Cl{sup +}) are reduced as compared to those made using a hot filament source.

  3. Recycling crop residues for use in recirculating hydroponic crop production.

    PubMed

    Mackowiak, C L; Garland, J L; Sager, J C

    1996-12-01

    As part of bioregenerative life support feasibility testing by NASA, crop residues are being used to resupply elemental nutrients to recirculating hydroponic crop production systems. Methods for recovering nutrients from crop residues have evolved from water soaking (leaching) to rapid aerobic bioreactor processing. Leaching residues recovered the majority of elements but it also recovered significant amounts of soluble organics. The high organic content of leachates was detrimental to plant growth. Aerobic bioreactor processing reduced the organic content ten-fold, which reduced or eliminated phytotoxic effects. Wheat and potato production studies were successful using effluents from reactors having with 8- to 1-day retention times. Aerobic bioreactor effluents supplied at least half of the crops elemental mass needs in these studies. Descriptions of leachate and effluent mineral content, biomass productivity, microbial activity, and nutrient budgets for potato and wheat are presented. PMID:11541570

  4. Dry fermentation of agricultural residues

    NASA Astrophysics Data System (ADS)

    Jewell, W. J.; Chandler, J. A.; Dellorto, S.; Fanfoni, K. J.; Fast, S.; Jackson, D.; Kabrick, R. M.

    1981-09-01

    A dry fermentation process is discussed which converts agricultural residues to methane, using the residues in their as produced state. The process appears to simplify and enhance the possibilities for using crop residues as an energy source. The major process variables investigated include temperature, the amount and type of inoculum, buffer requirements, compaction, and pretreatment to control the initial available organic components that create pH problems. A pilot-scale reactor operation on corn stover at a temperature of 550 C, with 25 percent initial total solids, a seed-to-feed ratio of 2.5 percent, and a buffer-to-feed ratio of 8 percent achieved 33 percent total volatile solids destruction in 60 days. Volumetric biogas yields from this unit were greater than 1 vol/vol day for 12 days, and greater than 0.5 vol/vol day for 32 days, at a substrate density of 169 kg/m (3).

  5. Sampling protocols for the detection of smokeless powder residues using capillary electrophoresis.

    PubMed

    MacCrehan, W A; Smith, K D; Rowe, W F

    1998-01-01

    Present techniques for the detection of gunshot residue rely primarily metallic primer components such as lead, barium and antimony. With the advent of reformulated primers that reduce or eliminate these elements, new methods for the detection of organic residue compounds will be needed. Micellar electrokinetic capillary electrophoresis (MECE) is one technique that has been successfully applied to the analysis of these smokeless powder residue compounds. Protocols for the recovery of the organic residue components under a variety of sampling conditions were evaluated and improved for MECE analysis. The collection of residue samples where external contaminants such as grease or blood were present on the residue substrate were investigated using both tape lifts and solvent swab protocols. In addition, residue component recovery using supercritical fluid extraction techniques was preliminarily evaluated for samples contaminated with blood. PMID:9456532

  6. Total radioactive residues and residues of [36Cl]chlorate in market size broilers.

    PubMed

    Smith, David J; Byrd, James A; Anderson, Robin C

    2007-07-11

    The oral administration of chlorate salts reduces the numbers of Gram-negative pathogens in gastrointestinal tracts of live food animals. Although the efficacy of chlorate salts has been demonstrated repeatedly, the technology cannot be introduced into commercial settings without first demonstrating that chlorate residues, and metabolites of chlorate remaining in edible tissues, represent a negligible risk to consumers. Typically, a first step in this risk assessment is to quantify the parent compound and to identify metabolites remaining in edible tissues of animals treated with the experimental compound. The objectives of this study were to determine the pathway(s) of chlorate metabolism in market broilers and to determine the magnitude of chlorate residues remaining in edible tissues. To this end, 12 broilers (6 weeks; 2.70+/-0.34 kg) were randomly assigned to three treatments of 7.4, 15.0, and 22.5 mM sodium [36Cl]chlorate dissolved in drinking water (n=4 broilers per treatment). Exposure to chlorate, dissolved in drinking water, occurred at 0 and 24 h (250 mL per exposure), feed was withdrawn at hour 38, water was removed at hour 48, and birds were slaughtered at hour 54 (16 h after feed removal and 8 h after water removal). The radioactivity was rapidly eliminated in excreta with 69-78% of the total administered radioactivity being excreted by slaughter. Total radioactive residues were proportional to dose in all edible tissues with chloride ion comprising greater than 98.5% of the radioactive residue for the tissue (9.4-97.8 ppm chlorate equivalents). Chlorate residues were typically greatest in the skin (0.33-0.82 ppm), gizzard (0.1-0.137 ppm), and dark muscle (0.05-0.14 ppm). Adipose, liver, and white muscle tissue contained chlorate concentrations from 0.03 to 0.13 ppm. In contrast, chlorate concentrations in excreta eliminated during the 6 h period prior to slaughter ranged from 53 to 71 ppm. Collectively, these data indicate that broilers rapidly

  7. Chemistry of combined residual chlorination

    SciTech Connect

    Leao, S.F.; Selleck, R.E.

    1982-01-01

    The decay of the combined chlorine residual was investigated in this work. Recent concerns about the formation of undesirable compounds such as chloroform with free residual chlorination have focused attention on the alternative use of combined residual chlorination. This work investigates the applicability of reactions proposed to describe the transformations and decay of the combined residual with time. Sodium hypochlorite was added to buffered solutions of ammonia with the chlorine residual being monitored over periods extending up to 10 days. The reaction was studied at four initial concentrations of hypochlorite of 100, 50, 25 and 10 mg/L as Cl/sub 2/ with molar application ratios of chlorine to ammonia, defined herein as M ratios, of 0.90, 0.50, 0.25 and 0.05 at each hypochlorite dose. Sixty-eight experiments were conducted at the pH of 6.6 and 7.2. The conclusions are: (1) in the absence of free chlorine, the concentration of NH/sub 3/ does not seem to affect the rate of disappearance of the residual other than through the formation of NHCl/sub 2/ by NH/sub 2/Cl hydrolysis; (2) the reaction between NHCl/sub 2/ and NH/sub 4//sup +/ to form NH/sub 2/Cl is either much slower than reported by Gray et. al. or the mechanism is different with a rate limiting step not involving NH/sub 3/ or NH/sub 4//sup +/; (3) a redox reaction in addition to the first-order decomposition of NHCl/sub 2/ appears necessary. Model simulation results indicated that a reaction of the type NH/sub 2/Cl + NHCl/sub 2/ ..-->.. P added to the first-order NHCl/sub 2/ decomposition can explain the results observed except at the higher chlorine doses.

  8. CHARACTERIZING PESTICIDE RESIDUE TRANSFER EFFICIENCIES USING FLUORESCENT TRACER IMAGING TECHNIQUES

    EPA Science Inventory

    To reduce the uncertainty associated with current estimates of children's exposure to pesticides by dermal contact and non-dietary ingestion, residue transfer data are required. Prior to conducting exhaustive studies, a screening study was conducted to identify the important pa...

  9. Sugarcane postharvest residue management in a temperate climate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Full retention of sugarcane (interspecific hybrids of Saccharum spp.) post-harvest residue often reduces subsequent ratoon crop yields in Louisiana. Experiments were conducted to determine the effects of different removal methods and removal timings on sugarcane growth and yield and to determine if...

  10. Estimating Crop Residue Distribution Using Airborne and Satellite Remote Sensing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop residue management and reduced tillage are commonly accepted best management practices that improve soil quality through the sequestration of soil organic carbon. A major goal of this study was to evaluate remote sensing data for rapid quantification of conservation tillage at the field and wa...

  11. 40 CFR 1065.705 - Residual and intermediate residual fuel.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... specifications for fuels meeting the definition of residual fuel in 40 CFR 80.2, including fuels marketed as... 991.0 1010.0 ISO 3675 or ISO 12185 (see also ISO 8217). Kinematic viscosity at 50 °C, max cSt 30.0...

  12. Collection of sugarcane crop residue for energy

    SciTech Connect

    Eiland, B.R.; Clayton, J.E.

    1982-12-01

    Crop residue left after sugarcane harvesting was recovered using a forage harvester and a large round baler. The quantity, bulk density and moisture content of the crop residue was determined in four fields. Crop residue from 7 ha was burned in boilers at a sugar mill. Samples of this residue were tested by a laboratory and compared to sugarcane bagasse.

  13. Residual Structures in Latent Growth Curve Modeling

    ERIC Educational Resources Information Center

    Grimm, Kevin J.; Widaman, Keith F.

    2010-01-01

    Several alternatives are available for specifying the residual structure in latent growth curve modeling. Two specifications involve uncorrelated residuals and represent the most commonly used residual structures. The first, building on repeated measures analysis of variance and common specifications in multilevel models, forces residual variances…

  14. Elevated atmospheric carbon dioxide effects on cotton plant residue decomposition

    SciTech Connect

    Torbert, H.A.; Prior, S.A.; Rogers, H.H.

    1995-09-01

    Assessing the impact of elevated atmospheric CO{sub 2} concentration on the global environment is hampered due to a lack of understanding of global C cycling. Carbon fixed within plant biomass ultimately enters the soil via plant residues, but the effects of elevated-CO{sub 2}-grown plant material on decomposition rates and long-term soil C storage are unknown. The objective of this study was to determine the decomposition rate of plant residues grown under an elevated CO{sub 2} environment as affected by soil type. Cotton (Gossypium hirsutum L. `Delta Pine 77`) samples were collected from a free-air CO{sub 2} enrichment (550 {mu}L L{sup -1}) experiment. The plant residues were incubated under ambient CO{sub 2} conditions to determine decomposition rates of leaves, stems, and roots and potential N and P mineralization-immobilization in three soil series. No significant difference was observed between plant residue grown under CO{sub 2} enrichment vs. ambient CO{sub 2} conditions for soil respiration or P mineralization-immobilization. Significantly greater net N immobilization was observed during the incubation in all soil types for plant residue grown at elevated CO{sub 2}. These results indicate that while decomposition of plant residue may not be reduced by CO{sub 2} enrichment, N dynamics may be markedly changed. 32 refs., 5 figs., 3 tabs.

  15. IMPROVED TECHNIQUES FOR RESIDUAL OZONE

    EPA Science Inventory

    Eight analytical methods for the determination of residual ozone in water are evaluated. Four are iodometric methods based on the reduction of ozone by iodide ion: the iodometric method, the amperometric method, the arsenic (III) back titration method, and the N, N-diethyl-p-phen...

  16. Leptogenesis and residual CP symmetry

    NASA Astrophysics Data System (ADS)

    Chen, Peng; Ding, Gui-Jun; King, Stephen F.

    2016-03-01

    We discuss flavour dependent leptogenesis in the framework of lepton flavour models based on discrete flavour and CP symmetries applied to the type-I seesaw model. Working in the flavour basis, we analyse the case of two general residual CP symmetries in the neutrino sector, which corresponds to all possible semi-direct models based on a preserved Z 2 in the neutrino sector, together with a CP symmetry, which constrains the PMNS matrix up to a single free parameter which may be fixed by the reactor angle. We systematically study and classify this case for all possible residual CP symmetries, and show that the R-matrix is tightly constrained up to a single free parameter, with only certain forms being consistent with successful leptogenesis, leading to possible connections between leptogenesis and PMNS parameters. The formalism is completely general in the sense that the two residual CP symmetries could result from any high energy discrete flavour theory which respects any CP symmetry. As a simple example, we apply the formalism to a high energy S 4 flavour symmetry with a generalized CP symmetry, broken to two residual CP symmetries in the neutrino sector, recovering familiar results for PMNS predictions, together with new results for flavour dependent leptogenesis.

  17. Pyrotechnic reaction residue particle analysis.

    PubMed

    Kosanke, Kenneth L; Dujay, Richard C; Kosanke, Bonnie J

    2006-03-01

    Pyrotechnic reaction residue particle (PRRP) production, sampling and analysis are all very similar to that for primer gunshot residue. In both cases, the preferred method of analysis uses scanning electron microscopy to locate suspect particles and then uses energy dispersive x-ray spectroscopy to characterize the particle's constituent chemical elements. There are relatively few times when standard micro-analytical chemistry performed on pyrotechnic residues may not provide sufficient information for forensic investigators. However, on those occasions, PRRP analysis provides a greatly improved ability to discriminate between materials of pyrotechnic origin and other unrelated substances also present. The greater specificity of PRRP analysis is the result of its analyzing a large number of individual micron-sized particles, rather than producing only a single integrated result such as produced using standard micro-analytical chemistry. For example, PRRP analyses are used to demonstrate its ability to successfully (1) discriminate between pyrotechnic residues and unrelated background contamination, (2) identify that two different pyrotechnic compositions had previously been exploded within the same device, and (3) establish the chronology of an incident involving two separate and closely occurring explosions. PMID:16566762

  18. Implication of Terminal Residues at Protein-Protein and Protein-DNA Interfaces.

    PubMed

    Martin, Olivier M F; Etheve, Loïc; Launay, Guillaume; Martin, Juliette

    2016-01-01

    Terminal residues of protein chains are charged and more flexible than other residues since they are constrained only on one side. Do they play a particular role in protein-protein and protein-DNA interfaces? To answer this question, we considered large sets of non-redundant protein-protein and protein-DNA complexes and analyzed the status of terminal residues and their involvement in interfaces. In protein-protein complexes, we found that more than half of terminal residues (62%) are either modified by attachment of a tag peptide (10%) or have missing coordinates in the analyzed structures (52%). Terminal residues are almost exclusively located at the surface of proteins (94%). Contrary to charged residues, they are not over or under-represented in protein-protein interfaces, but strongly prefer the peripheral region of interfaces when present at the interface (83% of terminal residues). The almost exclusive location of terminal residues at the surface of the proteins or in the rim regions of interfaces explains that experimental methods relying on tail hybridization can be successfully applied without disrupting the complexes under study. Concerning conformational rearrangement in protein-protein complexes, despite their expected flexibility, terminal residues adopt similar locations between the free and bound forms of the docking benchmark. In protein-DNA complexes, N-terminal residues are twice more frequent than C-terminal residues at interfaces. Both N-terminal and C-terminal residues are under-represented in interfaces, in contrast to positively charged residues, which are strongly favored. When located in protein-DNA interfaces, terminal residues prefer the periphery. N-terminal and C-terminal residues thus have particular properties with regard to interfaces, which cannot be reduced to their charged nature. PMID:27611671

  19. Escherichia coli Common Pilus (ECP) Targets Arabinosyl Residues in Plant Cell Walls to Mediate Adhesion to Fresh Produce Plants*

    PubMed Central

    Rossez, Yannick; Holmes, Ashleigh; Lodberg-Pedersen, Henriette; Birse, Louise; Marshall, Jacqueline; Willats, William G. T.; Toth, Ian K.; Holden, Nicola J.

    2014-01-01

    Outbreaks of verotoxigenic Escherichia coli are often associated with fresh produce. However, the molecular basis to adherence is unknown beyond ionic lipid-flagellum interactions in plant cell membranes. We demonstrate that arabinans present in different constituents of plant cell walls are targeted for adherence by E. coli common pilus (ECP; or meningitis-associated and temperature-regulated (Mat) fimbriae) for E. coli serotypes O157:H7 and O18:K1:H7. l-Arabinose is a common constituent of plant cell wall that is rarely found in other organisms, whereas ECP is widespread in E. coli and other environmental enteric species. ECP bound to oligosaccharides of at least arabinotriose or longer in a glycan array, plant cell wall pectic polysaccharides, and plant glycoproteins. Recognition overlapped with the antibody LM13, which binds arabinanase-sensitive pectic epitopes, and showed a preferential affinity for (1→5)-α-linked l-arabinosyl residues and longer chains of arabinan as demonstrated with the use of arabinan-degrading enzymes. Functional adherence in planta was mediated by the adhesin EcpD in combination with the structural subunit, EcpA, and expression was demonstrated with an ecpR–GFP fusion and ECP antibodies. Spinach was found to be enriched for ECP/LM13 targets compared with lettuce. Specific recognition of arabinosyl residues may help explain the persistence of E. coli in the wider environment and association of verotoxigenic E. coli with some fresh produce plants by exploitation of a glycan found only in plant, not animal, cells. PMID:25320086

  20. Performance of Container-Grown Loropetalum Grown in Clean Chip Residual Substrate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The idea of using forest residuals is gaining in popularity as a replacement for pine bark (PB) in nursery crop substrates due to reduced availability of PB. Clean Chip Residual (CCR) is a by-product of in-field forestry harvesting practices. This material, composed of roughly 50% wood, 40% bark, an...

  1. Distribution of multiple pesticide residues in apple segments after home processing.

    PubMed

    Rasmusssen, R R; Poulsen, M E; Hansen, H C B

    2003-11-01

    The effects of washing, storing, boiling, peeling, coring and juicing on pesticide residue were investigated for field-sprayed Discovery and Jonagold apples. Residues of chlorpyrifos, cypermethrin, deltamethrin, diazinon, endosulfan, endosulfan sulfate, fenitrothion, fenpropathrin, iprodione, kresoxim-methyl, lambda-cyhalothrin, quinalphos, tolylfluanid and vinclozolin in the processed apples were analysed by gas chromatography. Statistical analysis showed that reductions of 18-38% were required to obtain significant effects of processing practices, depending on pesticide and apple variety. Juicing and peeling the apples significantly reduced all pesticide residues. In the case of detectable pesticide residues, 1-24% were distributed in the juice and in the peeled apple. None of the pesticide residues was significantly reduced when the apples were subject to simple washing or coring. Storing significantly reduced five of the pesticide residues: diazinon, chlorpyrifos, fenitrothion, kresoxim-methyl and tolylfluanid, by 25-69%. Residues of the metabolite endosulfan sulfate were increased by 34% during storage. Boiling significantly reduced residues of fenitrothion and tolylfluanid by 32 and 81%, respectively. Only a few of the observed effects of processing could be explained by the physical or chemical characteristics of the pesticides. No differences in effect of processing due to apple variety were identified. PMID:14668155

  2. Analysis of residual tritium in an LP 50 product container

    SciTech Connect

    Wermer, J.R.

    1996-06-04

    The analysis was done by sampling coupons cut from the side of the vessel. Tests were performed to analyze the amount of residual tritium in the container wall, as well as the amount of tritium removed through exposure to moist air. Based on this data, the PC contained 62 curies of residual tritium. Air exposure and leaching of the coupons in aqua regia accounted for 27 curies. Recommendations are given for final processing of these containers in order to reduce the final tritium content.

  3. Alcohol production from agricultural and forestry residues

    SciTech Connect

    Dale, L; Opilla, R; Surles, T

    1980-09-01

    Technologies available for the production of ethanol from whole corn are reviewed. Particular emphasis is placed on the environmental aspects of the process, including land utilization and possible air and water pollutants. Suggestions are made for technological changes intended to improve the economics of the process as well as to reduce some of the pollution from by-product disposal. Ethanol may be derived from renewable cellulosic substances by either enzymatic or acid hydrolysis of cellulose to sugar, followed by conventional fermentation and distillation. The use of two agricultural residues - corn stover (field stalks remaining after harvest) and straw from wheat crops - is reviewed as a cellulosic feedstock. Two processes have been evaluated with regard to environmental impact - a two-stage acid process developed by G.T. Tsao of Purdue University and an enzymatic process based on the laboratory findings of C.R. Wilke of the University of California, Berkeley. The environmental residuals expected from the manufacture of methyl and ethyl alcohols from woody biomass are covered. The methanol is produced in a gasification process, whereas ethanol is produced by hydrolysis and fermentation processes similar to those used to derive ethanol from cellulosic materials.

  4. Alcohol production from agricultural and forestry residues

    SciTech Connect

    Opilla, R.; Dale, L.; Surles, T.

    1980-05-01

    A variety of carbohydrate sources can be used as raw material for the production of ethanol. Section 1 is a review of technologies available for the production of ethanol from whole corn. Particular emphasis is placed on the environmental aspects of the process, including land utilization and possible air and water pollutants. Suggestions are made for technological changes intended to improve the economics of the process as well as to reduce some of the pollution from by-product disposal. Ethanol may be derived from renewable cellulosic substances by either enzymatic or acid hydrolysis of cellulose to sugar, followed by conventional fermentation and distillation. Section 2 is a review of the use of two agricultural residues - corn stover (field stalks remaining after harvest) and straw from wheat crops - as a cellulosic feedstock. Two processes have been evaluated with regard to environmental impact - a two-stage acid process developed by G.T. Tsao of Purdue University and an enzymatic process based on the laboratory findings of C.R. Wilke of the University of California, Berkeley. Section 3 deals with the environmental residuals expected from the manufacture of methyl and ethyl alcohols from woody biomass. The methanol is produced in a gasification process, whereas ethanol is produced by hydrolysis and fermentation processes similar to those used to derive ethanol from cellulosic materials.

  5. Managing coal combustion residues in mines

    SciTech Connect

    2006-07-01

    Burning coal in electric utility plants produces, in addition to power, residues that contain constituents which may be harmful to the environment. The management of large volumes of coal combustion residues (CCRs) is a challenge for utilities, because they must either place the CCRs in landfills, surface impoundments, or mines, or find alternative uses for the material. This study focuses on the placement of CCRs in active and abandoned coal mines. The Committee on Mine Placement of Coal Combustion Wastes of the National Research Council believes that placement of CCRs in mines as part of the reclamation process may be a viable option for the disposal of this material as long as the placement is properly planned and carried out in a manner that avoids significant adverse environmental and health impacts. This report discusses a variety of steps that are involved in planning and managing the use of CCRs as minefills, including an integrated process of CCR characterization and site characterization, management and engineering design of placement activities, and design and implementation of monitoring to reduce the risk of contamination moving from the mine site to the ambient environment. Enforceable federal standards are needed for the disposal of CCRs in minefills to ensure that states have adequate, explicit authority and that they implement minimum safeguards. 267 refs., 6 apps.

  6. Strategies for preserving residual renal function in peritoneal dialysis patients

    PubMed Central

    Nongnuch, Arkom; Assanatham, Montira; Panorchan, Kwanpeemai; Davenport, Andrew

    2015-01-01

    Although there have been many advancements in the treatment of patients with chronic kidney disease (CKD) over the last 50 years, in terms of reducing cardiovascular risk, mortality remains unacceptably high, particularly for those patients who progress to stage 5 CKD and initiate dialysis (CKD5d). As mortality risk increases exponentially with progressive CKD stage, the question arises as to whether preservation of residual renal function once dialysis has been initiated can reduce mortality risk. Observational studies to date have reported an association between even small amounts of residual renal function and improved patient survival and quality of life. Dialysis therapies predominantly provide clearance for small water-soluble solutes, volume and acid-base control, but cannot reproduce the metabolic functions of the kidney. As such, protein-bound solutes, advanced glycosylation end-products, middle molecules and other azotaemic toxins accumulate over time in the anuric CKD5d patient. Apart from avoiding potential nephrotoxic insults, observational and interventional trials have suggested that a number of interventions and treatments may potentially reduce the progression of earlier stages of CKD, including targeted blood pressure control, reducing proteinuria and dietary intervention using combinations of protein restriction with keto acid supplementation. However, many interventions which have been proven to be effective in the general population have not been equally effective in the CKD5d patient, and so the question arises as to whether these treatment options are equally applicable to CKD5d patients. As strategies to help preserve residual renal function in CKD5d patients are not well established, we have reviewed the evidence for preserving or losing residual renal function in peritoneal dialysis patients, as urine collections are routinely collected, whereas few centres regularly collect urine from haemodialysis patients, and haemodialysis dialysis

  7. Neutron scattering residual stress measurements on gray cast iron brake discs

    SciTech Connect

    Spooner, S.; Payzant, E.A.; Hubbard, C.R.

    1996-11-01

    Neutron diffraction was used to investigate the effects of a heat treatment designed to remove internal residual stresses in brake discs. It is believed that residual stresses may change the rate of deformation of the discs during severe braking conditions when the disc temperature is increased significantly. Neutron diffraction was used to map out residual strain distributions in a production disc before and after a stress-relieving heat treatment. Results from these neutron diffraction experiments show that some residual strains were reduced by as much as 400 microstrain by stress relieving. 5 refs., 5 figs., 1 tab.

  8. Manual for applying fluidized-bed-combustion residue to agricultural lands. Research report

    SciTech Connect

    Stout, W.L.; Hern, J.L.; Korcak, R.F.; Carlson, C.W.

    1988-08-01

    Atmospheric fluidized-bed combustion (AFBC) is a process that reduces sulfur emissions from coal-fired electric-generating plants. The residue from the process is a mixture of alkaline oxides, calcium sulfate, and coal ash constituent. Since 1976, USDA/ARS has investigated the potential agriculture use of the residue. The investigations comprised an extensive series of laboratory, greenhouse, field plot, and animal-feeding experiments. The best and safest use of AFBC residue in agriculture was as a substitute for agricultural lime. The report contains guidelines for appling AFBC residue to agricultural lands.

  9. Residual Resistivity of Dilute Alloys

    NASA Astrophysics Data System (ADS)

    Vora, Aditya M.

    The residual resistivity for 156 dilute alloys of 19 hosts of different groups of the periodic table has been studied on the basis of the single parametric model potential formalism. Ashcroft's empty core model (EMC) potential is explored for the first time with five different local field correction functions, viz, Hartree (H), Taylor (T), Ichimaru-Utsumi (IU), Farid et al. (F), and Sarkar et al. (S) to investigate the effect of the exchange and correlation on the aforesaid properties. The comparison of the presently computed outcomes with the available theoretical and experimental data is highly encouraging. The investigation of residual resistivity is found to be quite sensitive to the selection of local field correction function, showing a significant variation with the change in the function.

  10. Primer residues deposited by handguns.

    PubMed

    Cooper, R; Guileyardo, J M; Stone, I C; Hall, V; Fletcher, L

    1994-12-01

    There is much anecdotal information being disseminated, even offered in expert witness testimony, concerning the deposit of primer residues on the hands of persons in front of the muzzle of handguns. We present data for 9 mm and 380 Auto pistols and for a 38 caliber revolver depicting the procedure for obtaining wipings taken from targets representing the hands of a gunshot victim. These wipings from pork tissue were then analyzed for the primer residue metals antimony, barium, and lead. The data show that the two primary metals, antimony and barium, are deposited on the targets out to 4 feet for the pistols and out to three feet for the 38-caliber revolver. Testing will continue in actual cases with the gun and ammunition involved in the shooting. PMID:7879775

  11. Catalytic combustion of residual fuels

    NASA Technical Reports Server (NTRS)

    Bulzan, D. L.; Tacina, R. R.

    1981-01-01

    A noble metal catalytic reactor was tested using two grades of petroleum derived residual fuels at specified inlet air temperatures, pressures, and reference velocities. Combustion efficiencies greater than 99.5 percent were obtained. Steady state operation of the catalytic reactor required inlet air temperatures of at least 800 K. At lower inlet air temperatures, upstream burning in the premixing zone occurred which was probably caused by fuel deposition and accumulation on the premixing zone walls. Increasing the inlet air temperature prevented this occurrence. Both residual fuels contained about 0.5 percent nitrogen by weight. NO sub x emissions ranged from 50 to 110 ppm by volume at 15 percent excess O2. Conversion of fuel-bound nitrogen to NO sub x ranged from 25 to 50 percent.

  12. Limits of adaptation, residual interferences

    NASA Technical Reports Server (NTRS)

    Mokry, Miroslav (Editor); Erickson, J. C., Jr.; Goodyer, Michael J.; Mignosi, Andre; Russo, Giuseppe P.; Smith, J.; Wedemeyer, Erich H.; Newman, Perry A.

    1990-01-01

    Methods of determining linear residual wall interference appear to be well established theoretically; however they need to be validated, for example by comparative studies of test data on the same model in different adaptive-wall wind tunnels as well as in passive, ventilated-wall tunnels. The GARTEur CAST 7 and the CAST 10/DOA 2 investigations are excellent examples of such comparative studies. Results to date in both one-variable and two-variable methods for nonlinear wall interference indicate that a great deal more research and validation are required. The status in 2D flow is advanced over that in 3D flow as is the case generally with adaptive-wall development. Nevertheless, it is now well established that for transonic testing with extensive supercritical flow present, significant wall interference is likely to exist in conventional ventilated test sections. Consequently, residual correction procedures require further development hand-in-hand with further adaptive-wall development.

  13. Technique for the determination of asphaltenes in crude oil residues

    SciTech Connect

    Pearson, C.D.; Huff, G.S.; Gharfeh, S.G.

    1986-12-01

    Recently, the authors reported a method for the determination of saturates, aromatics, and resins in deasphaltened crude oil residues by high-performance liquid chromatography using a flame ionization detector. The present work describes a filtration technique for the determination of asphaltenes in crude oil residues using disposable Millex filters. This technique reduces the filtration, washing, and equilibration time needed for asphaltene determination. Six crude oil residues that varied widely in asphaltene content were used to evaluate the precision of this technique. The values obtained by Millex filters were compared to the values obtained by a conventional method using filter papers. Agreement between the two methods was very good. Several methods have been reported for the separation and determination of asphaltenes. Speight et al. made a survey of the different asphaltene procedures and conducted the experimental work to determine the optimum conditions for asphaltene separation and determination. The operating parameters recommended by Speight were used in this work.

  14. Vitrification of NAC process residue

    SciTech Connect

    Merrill, R.A.; Whittington, K.F.; Peters, R.D.

    1995-12-31

    Vitrification tests have been performed with simulated waste compositions formulated to represent the residue which would be obtained from the treatment of low-level, nitrate wastes from Hanford and Oak Ridge by the nitrate to ammonia and ceramic (NAC) process. The tests were designed to demonstrate the feasibility of vitrifying NAC residue and to quantify the impact of the NAC process on the volume of vitrified waste. The residue from NAC treatment of low-level nitrate wastes consists primarily of oxides of aluminum and sodium. High alumina glasses were formulated to maximize the waste loading of the NAC product. Transparent glasses with up to 35 wt% alumina, and even higher contents in opaque glasses, were obtained at melting temperatures of 1,200 C to 1,400 C. A modified TCLP leach test showed the high alumina glasses to have good chemical durability, leaching significantly less than either the ARM-1 or the DWPF-EA high-level waste reference glasses. A significant increase in the final waste volume would be a major result of the NAC process on LLW vitrification. For Hanford wastes, NAC-treatment of nitrate wastes followed by vitrification of the residue will increase the final volume of vitrified waste by 50% to 90%; for Melton Valley waste from Oak Ridge, the increase in final glass volume will be 260% to 280%. The increase in volume is relative to direct vitrification of the waste in a 20 wt% Na{sub 2}O glass formulation. The increase in waste volume directly affects not only disposal costs, but also operating and/or capital costs. Larger plant size, longer operating time, and additional energy and additive costs are direct results of increases in waste volume. Such increases may be balanced by beneficial impacts on the vitrification process; however, those effects are outside the scope of this report.

  15. Vitrification of NAC process residue

    SciTech Connect

    Merrill, R.A.; Whittington, K.F.; Peters, R.D.

    1995-09-01

    Vitrification tests have been performed with simulated waste compositions formulated to represent the residue which would be obtained from the treatment of low-level, nitrate wastes from Hanford and Oak Ridge by the nitrate to ammonia and ceramic (NAC) process. The tests were designed to demonstrate the feasibility of vitrifying NAC residue and to quantify the impact of the NAC process on the volume of vitrified waste. The residue from NAC treatment of low-level nitrate wastes consists primarily of oxides of aluminum and sodium. High alumina glasses were formulated to maximize the waste loading of the NAC product. Transparent glasses with up to 35 wt% alumina, and even higher contents in opaque glasses, were obtained at melting temperatures of 1200{degrees}C to 1400{degrees}C. A modified TCLP leach test showed the high alumina glasses to have good chemical durability, leaching significantly less than either the ARM-1 or the DWPF-EA high-level waste reference glasses. A significant increase in the final waste volume would be a major result of the NAC process on LLW vitrification. For Hanford wastes, NAC-treatment of nitrate wastes followed by vitrification of the residue will increase the final volume of vitrified waste by 50% to 90%; for Melton Valley waste from Oak Ridge, the increase in final glass volume will be 260% to 280%. The increase in volume is relative to direct vitrification of the waste in a 20 wt% Na{sub 2}O glass formulation. The increase in waste volume directly affects not only disposal costs, but also operating and/or capital costs. Larger plant size, longer operating time, and additional energy and additive costs are direct results of increases in waste volume. Such increases may be balanced by beneficial impacts on the vitrification process; however, those effects are outside the scope of this report.

  16. Residue management at Rocky Flats

    SciTech Connect

    Olencz, J.

    1995-12-31

    Past plutonium production and manufacturing operations conducted at the Rocky Flats Environmental Technology Site (RFETS) produced a variety of plutonium-contaminated by-product materials. Residues are a category of these materials and were categorized as {open_quotes}materials in-process{close_quotes} to be recovered due to their inherent plutonium concentrations. In 1989 all RFETS plutonium production and manufacturing operations were curtailed. This report describes the management of plutonium bearing liquid and solid wastes.

  17. STUDY TO IDENTIFY IMPORTANT PARAMETERS FOR CHARACTERIZING PESTICIDE RESIDUE TRANSFER EFFICIENCIES

    EPA Science Inventory

    To reduce the uncertainty associated with current estimates of children's exposure to pesticides by dermal contact and non-dietary ingestion, residue transfer data are required. Prior to conducting exhaustive studies, a screening study to identify the important parameters for...

  18. COMBINING METHODS FOR THE REDUCTION OF OXYCHLORINE RESIDUALS IN DRINKING WATER

    EPA Science Inventory

    Previous investigations have shown ferrous iron application to be an effective and economically feasible method of removing residual chlorine dioxide and chlorite iron from drinking water. This treatment, however, was not effective in reducing concentrqations of chlorate iron. ...

  19. Evaluation of residue drum storage safety risks

    SciTech Connect

    Conner, W.V.

    1994-06-17

    A study was conducted to determine if any potential safety problems exist in the residue drum backlog at the Rocky Flats Plant. Plutonium residues stored in 55-gallon drums were packaged for short-term storage until the residues could be processed for plutonium recovery. These residues have now been determined by the Department of Energy to be waste materials, and the residues will remain in storage until plans for disposal of the material can be developed. The packaging configurations which were safe for short-term storage may not be safe for long-term storage. Interviews with Rocky Flats personnel involved with packaging the residues reveal that more than one packaging configuration was used for some of the residues. A tabulation of packaging configurations was developed based on the information obtained from the interviews. A number of potential safety problems were identified during this study, including hydrogen generation from some residues and residue packaging materials, contamination containment loss, metal residue packaging container corrosion, and pyrophoric plutonium compound formation. Risk factors were developed for evaluating the risk potential of the various residue categories, and the residues in storage at Rocky Flats were ranked by risk potential. Preliminary drum head space gas sampling studies have demonstrated the potential for formation of flammable hydrogen-oxygen mixtures in some residue drums.

  20. Field bioefficacy of deltamethrin residual spraying against dengue vectors.

    PubMed

    Rozilawati, H; Lee, H L; Mohd Masri, S; Mohd Noor, I; Rosman, S

    2005-12-01

    Field bioefficacy of residual-sprayed deltamethrin against Aedes vectors was evaluated in an urban residential area in Kuala Lumpur. The trial area consisted of single storey wood-brick houses and a block of flat. The houses were treated with outdoor residual spraying while the flat was used as an untreated control. Initial pre-survey using ovitrap surveillance indicated high Aedes population in the area. Deltamethrin WG was sprayed at a dosage of 25mg/m2 using a compression sprayer. The effectiveness of deltamethrin was determined by wall bioassay and ovitrap surveillance. The residual activity of 25mg/m2 deltamethrin was still effective for 6 weeks after treatment, based on biweekly bioassay results. Bioassay also indicated that both Aedes aegypti and Aedes albopictus were more susceptible on the wooden surfaces than on brick. Aedes aegypti was more susceptible than Ae. albopictus against deltamethrin. Residual spraying of deltamethrin was not very effective against Aedes in this study since the Aedes population in the study area did not reduce as indicated by the total number of larvae collected using the ovitrap (Wilcoxon Sign Test, p> 0.05). Further studies are required to improve the effectiveness of residual spraying against Aedes vectors. PMID:16883280

  1. Perchlorate Reductase Is Distinguished by Active Site Aromatic Gate Residues.

    PubMed

    Youngblut, Matthew D; Tsai, Chi-Lin; Clark, Iain C; Carlson, Hans K; Maglaqui, Adrian P; Gau-Pan, Phonchien S; Redford, Steven A; Wong, Alan; Tainer, John A; Coates, John D

    2016-04-22

    Perchlorate is an important ion on both Earth and Mars. Perchlorate reductase (PcrAB), a specialized member of the dimethylsulfoxide reductase superfamily, catalyzes the first step of microbial perchlorate respiration, but little is known about the biochemistry, specificity, structure, and mechanism of PcrAB. Here we characterize the biophysics and phylogeny of this enzyme and report the 1.86-Å resolution PcrAB complex crystal structure. Biochemical analysis revealed a relatively high perchlorate affinity (Km = 6 μm) and a characteristic substrate inhibition compared with the highly similar respiratory nitrate reductase NarGHI, which has a relatively much lower affinity for perchlorate (Km = 1.1 mm) and no substrate inhibition. Structural analysis of oxidized and reduced PcrAB with and without the substrate analog SeO3 (2-) bound to the active site identified key residues in the positively charged and funnel-shaped substrate access tunnel that gated substrate entrance and product release while trapping transiently produced chlorate. The structures suggest gating was associated with shifts of a Phe residue between open and closed conformations plus an Asp residue carboxylate shift between monodentate and bidentate coordination to the active site molybdenum atom. Taken together, structural and mutational analyses of gate residues suggest key roles of these gate residues for substrate entrance and product release. Our combined results provide the first detailed structural insight into the mechanism of biological perchlorate reduction, a critical component of the chlorine redox cycle on Earth. PMID:26940877

  2. PESTICIDE RESIDUE RECOVERIES FROM SURFACE WIPES

    EPA Science Inventory

    Human exposure is a consequence of pesticide use indoors with a primary source resulting from residue deposition on household surfaces. Accurate measurements of surface residues is essential for estimating exposure from different routes. Various procedures have been developed ...

  3. 48 CFR 250.104 - Residual powers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Residual powers. 250.104 Section 250.104 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT... Contractual Actions 250.104 Residual powers....

  4. 48 CFR 1850.104 - Residual powers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false Residual powers. 1850.104 Section 1850.104 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... 1850.104 Residual powers....

  5. 48 CFR 250.104 - Residual powers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Residual powers. 250.104 Section 250.104 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT... Contractual Actions 250.104 Residual powers....

  6. 48 CFR 1850.104 - Residual powers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false Residual powers. 1850.104 Section 1850.104 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... 1850.104 Residual powers....

  7. 48 CFR 970.5001 - Residual powers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Residual powers. 970.5001 Section 970.5001 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY....5001 Residual powers....

  8. 48 CFR 250.104 - Residual powers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Residual powers. 250.104 Section 250.104 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT... Contractual Actions 250.104 Residual powers....

  9. 48 CFR 970.5001 - Residual powers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Residual powers. 970.5001 Section 970.5001 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY....5001 Residual powers....

  10. 48 CFR 970.5001 - Residual powers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Residual powers. 970.5001 Section 970.5001 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY....5001 Residual powers....

  11. 48 CFR 970.5001 - Residual powers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Residual powers. 970.5001 Section 970.5001 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY....5001 Residual powers....

  12. 48 CFR 1850.104 - Residual powers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false Residual powers. 1850.104 Section 1850.104 Federal Acquisition Regulations System NATIONAL AERONAUTICS AND SPACE ADMINISTRATION... 1850.104 Residual powers....

  13. 48 CFR 250.104 - Residual powers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Residual powers. 250.104 Section 250.104 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT... Contractual Actions 250.104 Residual powers....

  14. 48 CFR 250.104 - Residual powers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Residual powers. 250.104 Section 250.104 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT... Contractual Actions 250.104 Residual powers....

  15. 48 CFR 970.5001 - Residual powers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Residual powers. 970.5001 Section 970.5001 Federal Acquisition Regulations System DEPARTMENT OF ENERGY AGENCY SUPPLEMENTARY....5001 Residual powers....

  16. Low-latency digital frequency synthesizer using the residue number system

    NASA Technical Reports Server (NTRS)

    Chren, William A., Jr.

    1993-01-01

    A low-latency frequency synthesizer using the Direct Digital Synthesis (DDS) technique has been designed. Called the Residue Assisted Frequency Synthesizer (RAFS), it exhibits frequency switching times which are reduced by more than 50 percent below previously published designs. The switching speed advantage is made possible by the use of the Residue Number System, which allows the pipeline lengths in the Phase Accumulator and other circuitry to be reduced significantly.

  17. 40 CFR 1065.705 - Residual and intermediate residual fuel.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... specifications for fuels meeting the definition of residual fuel in 40 CFR 80.2, including fuels marketed as...). Kinematic viscosity at 50 °C, max cSt 30.0 80.0 180.0 380.0 700.0 ISO 3104:1994/Cor 1:1997. Flash point, min... ISO 6245. Water, max (m3/m3)% 0.5 0.5 0.5 0.5 0.5 ISO 3733. Sulfur, max (kg/kg)% 3.50 4.00 4.50 4.50...

  18. 40 CFR 1065.705 - Residual and intermediate residual fuel.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... specifications for fuels meeting the definition of residual fuel in 40 CFR 80.2, including fuels marketed as...). Kinematic viscosity at 50 °C, max cSt 30.0 80.0 180.0 380.0 700.0 ISO 3104:1994/Cor 1:1997. Flash point, min... ISO 6245. Water, max (m3/m3)% 0.5 0.5 0.5 0.5 0.5 ISO 3733. Sulfur, max (kg/kg)% 3.50 4.00 4.50 4.50...

  19. 40 CFR 1065.705 - Residual and intermediate residual fuel.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... specifications for fuels meeting the definition of residual fuel in 40 CFR 80.2, including fuels marketed as...). Kinematic viscosity at 50 °C, max cSt 30.0 80.0 180.0 380.0 700.0 ISO 3104:1994/Cor 1:1997. Flash point, min... ISO 6245. Water, max (m3/m3)% 0.5 0.5 0.5 0.5 0.5 ISO 3733. Sulfur, max (kg/kg)% 3.50 4.00 4.50 4.50...

  20. 40 CFR 1065.705 - Residual and intermediate residual fuel.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... specifications for fuels meeting the definition of residual fuel in 40 CFR 80.2, including fuels marketed as...). Kinematic viscosity at 50 °C, max cSt 30.0 80.0 180.0 380.0 700.0 ISO 3104:1994/Cor 1:1997. Flash point, min... ISO 6245. Water, max (m3/m3)% 0.5 0.5 0.5 0.5 0.5 ISO 3733. Sulfur, max (kg/kg)% 3.50 4.00 4.50 4.50...

  1. The effectiveness of the head-turn-plus-chin-down maneuver for eliminating vallecular residue.

    PubMed

    Nagy, Ahmed; Peladeau-Pigeon, Melanie; Valenzano, Teresa Josephine; Namasivayam, Ashwini Marini; Steele, Catriona Margaret

    2016-04-01

    Purpose When swallowing efficiency is impaired, residue accumulates in the pharynx. Cued or spontaneous swallows in the head neutral position do not always successfully clear residue. We investigated the impact of a novel maneuver on residue clearance by combining a head turn with the chin down posture. Methods Data were collected from 26 participants who demonstrated persistent vallecular residue after an initial head neutral clearance swallow in videofluoroscopy. Participants were cued to perform a head-turn-plus-chin-down swallow, with the direction of head turn randomized. Pixel-based measures of residue in the vallecular space before and after the maneuver were made on still frame lateral images using ImageJ software. Measures of % full and the Normalized Residue Ratio Scale (NRRS) were extracted. Univariate analyses of variance were used to detect significant reductions in residue. Results On average, pre-maneuver measures showed residue filling 56-73% of the valleculae, depending on stimulus consistency (NRRS scores: 0.2-0.4). More than 80% of pre-swallow measures displayed NRRS ratios > 0.06, a threshold previously linked to increased risk of post-swallow aspiration. Conclusion The head-turn-plus-chin-down maneuver achieved significant reductions in residue for thin and nectar-thick fluids, suggesting that this maneuver can be effective in reducing persistent vallecular residue with these consistencies. PMID:27191873

  2. A Multi-Factor Analysis of Sustainable Agricultural Residue Removal Potential

    SciTech Connect

    Jared Abodeely; David Muth; Paul Adler; Eleanor Campbell; Kenneth Mark Bryden

    2012-10-01

    Agricultural residues have significant potential as a near term source of cellulosic biomass for bioenergy production, but sustainable removal of agricultural residues requires consideration of the critical roles that residues play in the agronomic system. Previous work has developed an integrated model to evaluate sustainable agricultural residue removal potential considering soil erosion, soil organic carbon, greenhouse gas emission, and long-term yield impacts of residue removal practices. The integrated model couples the environmental process models WEPS, RUSLE2, SCI, and DAYCENT. This study uses the integrated model to investigate the impact of interval removal practices in Boone County, Iowa, US. Residue removal of 4.5 Mg/ha was performed annually, bi-annually, and tri-annually and were compared to no residue removal. The study is performed at the soil type scale using a national soil survey database assuming a continuous corn rotation with reduced tillage. Results are aggregated across soil types to provide county level estimates of soil organic carbon changes and individual soil type soil organic matter content if interval residue removal were implemented. Results show interval residue removal is possible while improving soil organic matter. Implementation of interval removal practices provide greater increases in soil organic matter while still providing substantial residue for bioenergy production.

  3. Chlorpyrifos residual behaviors in field crops and transfers during duck pellet feed processing.

    PubMed

    Li, Rui; Wei, Wei; He, Liang; Hao, Lili; Ji, Xiaofeng; Zhou, Yu; Wang, Qiang

    2014-10-22

    Chlorpyrifos is a widely used organophosphorus pesticide in agricultural crops (including food) and animal feeds in China, resulting in heavy contamination. Many studies have focused on the food-processing effects on chlorpyrifos removal, but sufficient information is not observed for feed-processing steps. Here, chlorpyrifos residual behaviors in field crops and its transfers in duck pellet feed-processing steps were evaluated. In field trials, the highest residues for rice grain, shelled corn, and soybean seed were 12.0, 0.605, and 0.220 mg/kg, respectively. Residues of all rice grain and about half of shelled corn exceeded the maximum residue limits (MRLs) of China, and five soybean seeds exceeded the MRL of China. Chlorpyrifos residue was reduced 38.2% in brown rice after the raw rice grain was hulled. The residue in bran increased 71.2% after milling from brown rice. During the squashing step, the residue reduced 73.8% in soybean meal. The residues reduced significantly (23.7-36.8%) during the process of granulating for rice, maize, and soybean products. Comparatively, the grinding process showed only limited influence on chlorpyrifos removal (<10%). The residues of duck pellet feeds produced from highly contaminated raw materials of this study were 1.01 mg/kg (maize-soybean feed) and 3.20 mg/kg (rice-soybean feed), which were much higher than the generally accepted value (>0.1 mg/kg) for animal feeding. Chlorpyrifos residues were removed significantly by processing steps of pellet feeds, but the residue of raw materials was the determining factor for the safety of duck feeding. PMID:25310710

  4. Measurement and correlation of conditions for entrapment and mobilization of residual oil. Final report

    SciTech Connect

    Morrow, N.R.

    1981-09-01

    This report covers a two year research project concerned with factors which affect the entrapment and mobilization of residual oil. The project is composed of six major tasks: (1) capillary number relationships for rock samples; (2) residual oil saturations near the wellbore; (3) residual oil structure; (4) effect of gravity on residual saturation; (5) magnitude of residual oil saturation; and (6) effects of wettability on capillary number relationships. Detailed progress reports are presented for each task. Some of the highlights are: measurements of relationships between the ratio of viscous to capillary forces and the reduction in normal waterflood residual oil for a variety of rock types indicate the relative ease with which residual oil can be immiscibly displaced by a tertiary process; in reducing the amount of trapped oil to 50% of normal residual oil saturation, recovery of continuous oil is significantly easier than mobilization of trapped oil; the relative permeabilities of the water phase at reduced residual oil saturations were found to be independent of the displacement mechanism of oil movement by which the reduced residual saturations were achieved; a technique involving solidification of the immobile oil phase and subsequent separation has been developed and electron micrographs have been made of the solid blobs; gravity forces can become important at the ultralow interfacial tension values encountered such as in surfactant flooding; provided capillary forces are dominant, residual saturation in unconsolidated media is independent of both particle size and size distribution; for velocities ranging from below to well above typical field flow rates, contact angles at roughened low energy surfaces changed by no more than a few degrees.

  5. Protein thermal denaturation is modulated by central residues in the protein structure network.

    PubMed

    Souza, Valquiria P; Ikegami, Cecília M; Arantes, Guilherme M; Marana, Sandro R

    2016-03-01

    Network structural analysis, known as residue interaction networks or graphs (RIN or RIG, respectively) or protein structural networks or graphs (PSN or PSG, respectively), comprises a useful tool for detecting important residues for protein function, stability, folding and allostery. In RIN, the tertiary structure is represented by a network in which residues (nodes) are connected by interactions (edges). Such structural networks have consistently presented a few central residues that are important for shortening the pathways linking any two residues in a protein structure. To experimentally demonstrate that central residues effectively participate in protein properties, mutations were directed to seven central residues of the β-glucosidase Sfβgly (β-d-glucoside glucohydrolase; EC 3.2.1.21). These mutations reduced the thermal stability of the enzyme, as evaluated by changes in transition temperature (Tm ) and the denaturation rate at 45 °C. Moreover, mutations directed to the vicinity of a central residue also caused significant decreases in the Tm of Sfβgly and clearly increased the unfolding rate constant at 45 °C. However, mutations at noncentral residues or at surrounding residues did not affect the thermal stability of Sfβgly. Therefore, the data reported in the present study suggest that the perturbation of the central residues reduced the stability of the native structure of Sfβgly. These results are in agreement with previous findings showing that networks are robust, whereas attacks on central nodes cause network failure. Finally, the present study demonstrates that central residues underlie the functional properties of proteins. PMID:26785700

  6. SPECIATION OF ELEMENTS IN INCINERATION RESIDUES

    EPA Science Inventory

    Knowledge as to the speciation of elements in incineration residues is important for the successful management and utilization of the residues and for modelling and predicting their leaching behavior. s part of a larger research effort on speciation in combustion residues, ESP as...

  7. COMPOSITION AND DECOMPOSITION OF PEANUT RESIDUES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Limited information exists on the mineralizable nitrogen (N) content of peanut (Arachis hypogaea L.) residue. The objective of this study was to determine the N contribution of pre- and post harvest peanut residue on two soil types. Aboveground peanut residue (cv. Georgia Green) was collected prio...

  8. 9 CFR 311.39 - Biological residues.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Biological residues. 311.39 Section... Biological residues. Carcasses, organs, or other parts of carcasses of livestock shall be condemned if it is determined that they are adulterated because of the presence of any biological residues....

  9. 9 CFR 311.39 - Biological residues.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Biological residues. 311.39 Section... Biological residues. Carcasses, organs, or other parts of carcasses of livestock shall be condemned if it is determined that they are adulterated because of the presence of any biological residues....

  10. 9 CFR 311.39 - Biological residues.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Biological residues. 311.39 Section... Biological residues. Carcasses, organs, or other parts of carcasses of livestock shall be condemned if it is determined that they are adulterated because of the presence of any biological residues....

  11. 9 CFR 311.39 - Biological residues.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Biological residues. 311.39 Section... Biological residues. Carcasses, organs, or other parts of carcasses of livestock shall be condemned if it is determined that they are adulterated because of the presence of any biological residues....

  12. 9 CFR 311.39 - Biological residues.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Biological residues. 311.39 Section... Biological residues. Carcasses, organs, or other parts of carcasses of livestock shall be condemned if it is determined that they are adulterated because of the presence of any biological residues....

  13. Management of post-harvest residue blanket

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Timely and effective residue management is essential for maximum sugar yields. Several studies were implemented in 2003 and harvested in 2004 in an effort to increase the effectiveness of residue management practices. Six studies were conducted to determine the effect of residue removal timing a...

  14. 48 CFR 50.104 - Residual powers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Residual powers. 50.104... EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions 50.104 Residual powers. This section prescribes standards and procedures for exercising residual powers under Pub. L....

  15. 48 CFR 50.104 - Residual powers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Residual powers. 50.104... EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions 50.104 Residual powers. This section prescribes standards and procedures for exercising residual powers under Pub. L....

  16. 48 CFR 50.104 - Residual powers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Residual powers. 50.104... EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions 50.104 Residual powers. This section prescribes standards and procedures for exercising residual powers under Pub. L....

  17. 48 CFR 50.104 - Residual powers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Residual powers. 50.104... EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions 50.104 Residual powers. This section prescribes standards and procedures for exercising residual powers under Pub. L....

  18. 48 CFR 50.104 - Residual powers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Residual powers. 50.104... EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions 50.104 Residual powers. This section prescribes standards and procedures for exercising residual powers under Pub. L....

  19. Microbial degradation of post-harvest residues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Management of post-harvest residues, produced during the green cane harvesting of sugarcane in Louisiana, has become an increasingly important issue for producers, particularly in areas where burning of the residues is banned or restricted. If the residues, which range from 4-8 tonnes per hectare, ...

  20. Finite-state residual vector quantizer for image coding

    NASA Astrophysics Data System (ADS)

    Huang, Steve S.; Wang, Jia-Shung

    1993-10-01

    Finite state vector quantization (FSVQ) has been proven during recent years to be a high quality and low bit rate coding scheme. A FSVQ has achieved the efficiency of a small codebook (the state codebook) VQ while maintaining the quality of a large codebook (the master codebook) VQ. However, the large master codebook has become a primary limitation of FSVQ if the implementation is carefully taken into account. A large amount of memory would be required in storing the master codebook and also much effort would be spent in maintaining the state codebook if the master codebook became too large. This problem could be partially solved by the mean/residual technique (MRVQ). That is, the block means and the residual vectors would be separately coded. A new hybrid coding scheme called the finite state residual vector quantization (FSRVQ) is proposed in this paper for the sake of utilizing both advantage in FSVQ and MRVQ. The codewords in FSRVQ were designed by removing the block means so as to reduce the codebook size. The block means were predicted by the neighboring blocks to reduce the bit rate. Additionally, the predicted means were added to the residual vectors so that the state codebooks could be generated entirely. The performance of FSRVQ was indicated from the experimental results to be better than that of both ordinary FSVQ and RMVQ uniformly.

  1. Outlet baffles: Effect on liquid residuals from zero-gravity draining of hemispherically ended cylinders

    NASA Technical Reports Server (NTRS)

    Symons, E. P.

    1972-01-01

    An experimental investigation was conducted to study the relative effectiveness of various outlet baffles in reducing liquid residuals resulting from the draining of hemispherically ended cylindrical tanks in a weightless environment. Three different baffles were employed. The relative effectiveness of each baffle was determined by comparing the results obtained, in the form of liquid residuals, with results for an unbaffled tank. Data indicate that all the baffles tested reduced residuals. Reductions betweem 10 and 60 percent were obtained, depending on baffle geometry and outlfow Weber number.

  2. Wood residues: trash or treasure

    SciTech Connect

    Bolgiano, C.

    1983-12-01

    Forest residues have acquired new economic value since the growth of the wood-energy markets has prompted private woodlot owners to begin managing and harvesting their forests after nearly a century of neglect. Estimates place half the commercial forests as overstocked, with poor-quality trees and unmarketable varieties, as well as standing dead or fallen trees and slash which are aesthetically bad. Overzealous cleansing of the forest floor, however, will deplete forests soils of nutrients and expose them to erosion in addition to destroying wildlife habitat. A compromise is needed to balance the ecological and economic benefits. (DCK)

  3. Process to recycle shredder residue

    DOEpatents

    Jody, Bassam J.; Daniels, Edward J.; Bonsignore, Patrick V.

    2001-01-01

    A system and process for recycling shredder residue, in which separating any polyurethane foam materials are first separated. Then separate a fines fraction of less than about 1/4 inch leaving a plastics-rich fraction. Thereafter, the plastics rich fraction is sequentially contacted with a series of solvents beginning with one or more of hexane or an alcohol to remove automotive fluids; acetone to remove ABS; one or more of EDC, THF or a ketone having a boiling point of not greater than about 125.degree. C. to remove PVC; and one or more of xylene or toluene to remove polypropylene and polyethylene. The solvents are recovered and recycled.

  4. Organochlorine residues in starlings, 1972.

    PubMed

    Nickerson, P R; Barbehenn, K R

    1975-03-01

    During the fall of 1972 starlings were collected from 130 sites in conjunction with the National Pesticide Monitoring Program. They were analyzed for DDT and its metabolites, dieldrin, heptachlor epoxide, benzene hexachloride, polychlorinated biphenyls and, for the first time in the series, oxychlordane and HCB. Mean DDT and dieldrin residue levels have declined significantly since 1967 and a regression analysis suggests that levels of DDT and its metabolites should fall below a mean of 0.1 ppm for the 1974 starling collection. PMID:1161450

  5. 40 CFR 180.519 - Bromide ion and residual bromine; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Bromide ion and residual bromine... Tolerances § 180.519 Bromide ion and residual bromine; tolerances for residues. (a) General. The food additives, bromide ion and residual bromine, may be present in water, potable in accordance with...

  6. 40 CFR 180.519 - Bromide ion and residual bromine; tolerances for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Bromide ion and residual bromine... Tolerances § 180.519 Bromide ion and residual bromine; tolerances for residues. (a) General. The food additives, bromide ion and residual bromine, may be present in water, potable in accordance with...

  7. 40 CFR 180.519 - Bromide ion and residual bromine; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Bromide ion and residual bromine... Tolerances § 180.519 Bromide ion and residual bromine; tolerances for residues. (a) General. The food additives, bromide ion and residual bromine, may be present in water, potable in accordance with...

  8. 40 CFR 180.519 - Bromide ion and residual bromine; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Bromide ion and residual bromine... Tolerances § 180.519 Bromide ion and residual bromine; tolerances for residues. (a) General. The food additives, bromide ion and residual bromine, may be present in water, potable in accordance with...

  9. 40 CFR 180.519 - Bromide ion and residual bromine; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Bromide ion and residual bromine... Tolerances § 180.519 Bromide ion and residual bromine; tolerances for residues. (a) General. The food additives, bromide ion and residual bromine, may be present in water, potable in accordance with...

  10. Managing residual limb hyperhidrosis in wounded warriors.

    PubMed

    Pace, Sarah; Kentosh, Joshua

    2016-06-01

    Residual limb dermatologic problems are a common concern among young active traumatic amputee patients who strive to maintain an active lifestyle. Hyperhidrosis of residual limbs is a recognized inciting factor that often contributes to residual limb dermatoses and is driven by the design of the prosthetic liner covering the residual limb. Treatment of hyperhidrosis in this population presents a unique challenge. Several accepted treatments of hyperhidrosis can offer some relief but have been limited by lack of results or side-effect profiles. Microwave thermal ablation has presented an enticing potential for residual limb hyperhidrosis. PMID:27416083

  11. Fiber-optic polymer residue monitor

    SciTech Connect

    Pfeifer, K.B.; Jarecki, R.L. Jr.; Dalton, T.J.

    1998-10-01

    Semiconductor processing tools that use a plasma to etch polysilicon or oxides produce residue polymers that build up on the exposed surfaces of the processing chamber. These residues are generally stressed and with time can cause flaking onto wafers resulting in yield loss. Currently, residue buildup is not monitored, and chambers are cleaned at regular intervals resulting in excess downtime for the tool. In addition, knowledge of the residue buildup rate and index of refraction is useful in determining the state of health of the chamber process. The authors have developed a novel optical fiber-based robust sensor that allows measurement of the residue polymer buildup while not affecting the plasma process.

  12. Inhibited Release of Mobile Contaminants from Hanford Tank Residual Waste

    SciTech Connect

    Cantrell, Kirk J.; Heald, Steve M.; Arey, Bruce W.; Lindberg, Michael J.

    2011-03-03

    Investigations of contaminant release from Hanford Site tank residual waste have indicated that in some cases certain contaminants of interest (Tc and Cr) exhibit inhibited release. The percentage of Tc that dissolved from residual waste from tanks 241-C-103, 241-C-106, 241-C-202, and 241-C-203 ranged from approximately 6% to 10%. The percent leachable Cr from residual waste from tanks C-103, C 202, and C-203 ranged from approximately 1.1% to 44%. Solid phase characterization results indicate that the recalcitrant forms of these contaminants are associated with iron oxides. X-ray absorption near edge structure analysis of Tc and Cr in residual waste indicates that these contaminants occur in Fe oxide particles as their lower, less soluble oxidation states [Tc(IV) and Cr(III)]. The form of these contaminants is likely as oxides or hydroxides incorporated within the structure of the Fe oxide. Leaching behavior of U from tank residual waste was studied using deionized water, and CaCO3 and Ca(OH)2 saturated solutions as leachants. The release behavior of U from tank residual waste is complex. Initial U concentrations in water and CaCO3 leachants are high due to residual amounts of the highly soluble U mineral cejkaite. As leaching and dilution occur NaUO2PO4 {center_dot} xH2O, Na2U2O7(am) and schoepite (or a similar phase) become the solubility controlling phases for U. In the case of the Ca(OH)2 leachant, U release from tank residual waste is dramatically reduced. Thermodynamic modeling indicates that the solubility of CaUO4(c) controls release of U from residual waste in the Ca(OH)2 leachants. It is assumed the solubility controlling phase is actually a hydrated version of CaUO4 with a variable water content ranging from CaUO4 to CaUO4 {center_dot} (H2O). The critically reviewed value for CaUO4(c) (log KSP0 = 15.94) produced good agreement with our experimental data for the Ca(OH)2 leachates.

  13. Measuring the reduced shear

    SciTech Connect

    Zhang, Jun

    2011-11-01

    Neglecting the second order corrections in weak lensing measurements can lead to a few percent uncertainties on cosmic shears, and becomes more important for cluster lensing mass reconstructions. Existing methods which claim to measure the reduced shears are not necessarily accurate to the second order when a point spread function (PSF) is present. We show that the method of Zhang (2008) exactly measures the reduced shears at the second order level in the presence of PSF. A simple theorem is provided for further confirming our calculation, and for judging the accuracy of any shear measurement method at the second order based on its properties at the first order. The method of Zhang (2008) is well defined mathematically. It does not require assumptions on the morphologies of galaxies and the PSF. To reach a sub-percent level accuracy, the CCD pixel size is required to be not larger than 1/3 of the Full Width at Half Maximum (FWHM) of the PSF, regardless of whether the PSF has a power-law or exponential profile at large distances. Using a large ensemble (∼>10{sup 7}) of mock galaxies of unrestricted morphologies, we study the shear recovery accuracy under different noise conditions. We find that contaminations to the shear signals from the noise of background photons can be removed in a well defined way because they are not correlated with the source shapes. The residual shear measurement errors due to background noise are consistent with zero at the sub-percent level even when the amplitude of such noise reaches about 1/10 of the source flux within the half-light radius of the source. This limit can in principle be extended further with a larger galaxy ensemble in our simulations. On the other hand, the source Poisson noise remains to be a cause of systematic errors. For a sub-percent level accuracy, our method requires the amplitude of the source Poisson noise to be less than 1/80 ∼ 1/100 of the source flux within the half-light radius of the source

  14. Management of Antibiotic Residues from Agricultural Sources: Use of Composting to Reduce Chlortetracycline Residues in Beef Manure from Treated Animals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chlortetracycline (CTC) is one of only ten antibiotics licensed in the U.S.A. for use as a growth promoter for livestock. The widespread use of CTC may contribute to development of antibiotic-resistant bacteria. The objective of this study was to determine the effect of composting on the fate of C...

  15. 40 CFR 180.432 - Lactofen; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Lactofen; tolerances for residues. (a) General. Tolerances are established for residues of the herbicide... for residues of the herbicide lactofen, including its metabolites and degradates, in or on...

  16. 40 CFR 180.432 - Lactofen; tolerances for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Lactofen; tolerances for residues. (a) General. Tolerances are established for residues of the herbicide... for residues of the herbicide lactofen, including its metabolites and degradates, in or on...

  17. 40 CFR 180.432 - Lactofen; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Lactofen; tolerances for residues. (a) General. Tolerances are established for residues of the herbicide... for residues of the herbicide lactofen, including its metabolites and degradates, in or on...

  18. 40 CFR 180.432 - Lactofen; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Lactofen; tolerances for residues. (a) General. Tolerances are established for residues of the herbicide... for residues of the herbicide lactofen, including its metabolites and degradates, in or on...

  19. RESIDUAL STRESSES IN 3013 CONTAINERS

    SciTech Connect

    Mickalonis, J.; Dunn, K.

    2009-11-10

    The DOE Complex is packaging plutonium-bearing materials for storage and eventual disposition or disposal. The materials are handled according to the DOE-STD-3013 which outlines general requirements for stabilization, packaging and long-term storage. The storage vessels for the plutonium-bearing materials are termed 3013 containers. Stress corrosion cracking has been identified as a potential container degradation mode and this work determined that the residual stresses in the containers are sufficient to support such cracking. Sections of the 3013 outer, inner, and convenience containers, in both the as-fabricated condition and the closure welded condition, were evaluated per ASTM standard G-36. The standard requires exposure to a boiling magnesium chloride solution, which is an aggressive testing solution. Tests in a less aggressive 40% calcium chloride solution were also conducted. These tests were used to reveal the relative stress corrosion cracking susceptibility of the as fabricated 3013 containers. Significant cracking was observed in all containers in areas near welds and transitions in the container diameter. Stress corrosion cracks developed in both the lid and the body of gas tungsten arc welded and laser closure welded containers. The development of stress corrosion cracks in the as-fabricated and in the closure welded container samples demonstrates that the residual stresses in the 3013 containers are sufficient to support stress corrosion cracking if the environmental conditions inside the containers do not preclude the cracking process.

  20. Residual number processing in dyscalculia.

    PubMed

    Cappelletti, Marinella; Price, Cathy J

    2014-01-01

    Developmental dyscalculia - a congenital learning disability in understanding numerical concepts - is typically associated with parietal lobe abnormality. However, people with dyscalculia often retain some residual numerical abilities, reported in studies that otherwise focused on abnormalities in the dyscalculic brain. Here we took a different perspective by focusing on brain regions that support residual number processing in dyscalculia. All participants accurately performed semantic and categorical colour-decision tasks with numerical and non-numerical stimuli, with adults with dyscalculia performing slower than controls in the number semantic tasks only. Structural imaging showed less grey-matter volume in the right parietal cortex in people with dyscalculia relative to controls. Functional MRI showed that accurate number semantic judgements were maintained by parietal and inferior frontal activations that were common to adults with dyscalculia and controls, with higher activation for participants with dyscalculia than controls in the right superior frontal cortex and the left inferior frontal sulcus. Enhanced activation in these frontal areas was driven by people with dyscalculia who made faster rather than slower numerical decisions; however, activation could not be accounted for by response times per se, because it was greater for fast relative to slow dyscalculics but not greater for fast controls relative to slow dyscalculics. In conclusion, our results reveal two frontal brain regions that support efficient number processing in dyscalculia. PMID:24266008

  1. Effect of Extraction Conditions on the Saccharide (Neutral and Acidic) Composition of the Crude Pectic Extract from Various Agro-Industrial Residues.

    PubMed

    Babbar, Neha; Roy, Sandra Van; Wijnants, Marc; Dejonghe, Winnie; Caligiani, Augusta; Sforza, Stefano; Elst, Kathy

    2016-01-13

    The influence of different extraction methodologies was assessed on the composition of both neutral (arabinose, rhamnose, galactose) and acidic (galacturonic acid) pectic polysaccharides obtained from four agro-industrial residues, namely, berry pomace (BP), onion hulls (OH), pressed pumpkin (PP), and sugar beet pulp (SBP). For acidic pectic polysaccharides, the extraction efficiency was obtained as BP (nitric acid-assisted extraction, 2 h, 62.9%), PP (enzymatic-assisted extraction, 12 h, 75.0%), SBP (enzymatic-assisted extraction, 48 h, 89.8%; and nitric acid-assisted extraction, 4 h, 76.5%), and OH (sodium hexametaphosphate-assisted extraction, 0.5 h, 100%; and ammonium oxalate-assisted extraction, 0.5 h, 100%). For neutral pectic polysaccharides, the following results were achieved: BP (enzymatic-assisted extraction, 24 h, 85.9%), PP (nitric acid-assisted extraction, 6 h, 82.2%), and SBP (enzymatic assisted extraction, 48 h, 97.5%; and nitric acid-assisted extraction, 4 h, 83.2%). On the basis of the high recovery of pectic sugars, SBP and OH are interesting candidates for the further purification of pectin and production of pectin-derived products. PMID:26652767

  2. Saccharification of pumpkin residues by coculturing of Trichoderma reesei RUT-C30 and Phanerochaete chrysosporium Burdsall with delayed inoculation timing.

    PubMed

    Yang, Rui; Meng, Demei; Hu, Xiaosong; Ni, Yuanying; Li, Quanhong

    2013-09-25

    Trichoderma reesei and Phanerochaete chrysosporium with different lignocellulose-degrading enzyme systems have received much attention due to their ability to biodegrade lignocellulosic biomass. However, the synergistic effect of the two fungi on lignocellulose degradation is unknown. Herein, a cocultivation of T. reesei RUT-C30 and P. chrysosporium Burdsall for biodegradation of lignocellulosic pumpkin residues (PRS) was developed to produce soluble saccharide. Results indicated that a cocultivation of the two fungi with P. chrysosporium Burdsall inoculation delayed for 1.5 days produced the highest saccharide yield of 53.08% (w/w), and only 20.83% (w/w) of PRS were left after one batch of fermentation. In addition, this strategy increased the activities of secreted cellulases (endoglucanase, cellobiohydrolase, and β-glucosidase) and ligninases (lignin peroxidase and manganese peroxidase), which correlated to the increased saccharide yield. Besides, the resulting monosaccharides including glucose (1.23 mg/mL), xylose (0.13 mg/mL), arabinose (0.46 mg/mL), and fructose (0.21 mg/mL) from cocultures exhibited much higher yields than those from monoculture, which provides basal information for further fermentation research. This bioconversion of PRS into soluble sugars by cocultured fungal species provides a low cost method based on lignocellulose for potential biofuels or other bioproduct production. PMID:24020787

  3. Residual Oxygen on Nb Heated to 500 C

    SciTech Connect

    Kirby, R.; King, F.K.; Padamsee, H.; /Cornell U., LEPP

    2005-06-10

    The superconducting accelerating cavities for the International Linear Collider will be constructed of high-residual resistivity ratio (RRR) niobium sheet. Excessive oxygen within the skin depth (several microns) will reduce the RRR and increase resistive losses. We measure the thickness of this oxide layer, following bakeout simulation, to be about 0.5 nm thick. The results suggest that this layer will very slowly disappear from the top five nm at 500 C.

  4. The potential of residues of furfural and biogas as calcareous soil amendments for corn seed production.

    PubMed

    Zhao, Yunchen; Yan, Zhibin; Qin, Jiahai; Ma, Zhijun; Zhang, Youfu; Zhang, Li

    2016-04-01

    Intensive corn seed production in Northwest of China produced large amounts of furfural residues, which represents higher treatment cost and environmental issue. The broad calcareous soils in the Northwest of China exhibit low organic matter content and high pH, which led to lower fertility and lower productivity. Recycling furfural residues as soil organic and nutrient amendment might be a promising agricultural practice to calcareous soils. A 3-year field study was conducted to evaluate the effects of furfural as a soil amendment on corn seed production on calcareous soil with compared to biogas residues. Soil physical-chemical properties, soil enzyme activities, and soil heavy metal concentrations were assessed in the last year after the last application. Corn yield was determined in each year. Furfural residue amendments significantly decreased soil pH and soil bulk density. Furfural residues combined with commercial fertilizers resulted in the greater cumulative on soil organic matter, total phosphorus, available phosphorus, available potassium, and cation exchange capacity than that of biogas residue. Simultaneously, urease, invertase, catalase, and alkaline phosphatase increased even at the higher furfural application rates. Maize seed yield increased even with lower furfural residue application rates. Furfural residues resulted in lower Zn concentration and higher Cd concentration than that of biogas residues. Amendment of furfural residues led to higher soil electrical conductivity (EC) than that of biogas residues. The addition of furfural residues to maize seed production may be considered to be a good strategy for recycling the waste, converting it into a potential resource as organic amendment in arid and semi-arid calcareous soils, and may help to reduce the use of mineral chemical fertilizers in these soils. However, the impact of its application on soil health needs to be established in long-term basis. PMID:26606935

  5. Electrodeposition of low residual stress CoNiMnP hard magnetic thin films for magnetic MEMS actuators

    NASA Astrophysics Data System (ADS)

    Guan, Shan; Nelson, Bradley J.

    2005-04-01

    A new technique for electrodeposition of CoNiMnP hard magnetic thin films is developed to provide thin films with low residual stress and magnetic properties useful for MEMS applications. Processing parameters including applied current density, film thickness, pH and temperature of the electrolyte are regulated in order to reduce residual stress of the film. In addition, a hybrid residual stress reliever composed of sodium saccharine and a rare-earth salts mixture of Ce 2(SO 4) 3 and Nd 2(SO 4) 3 is created to further reduce the residual stress, eliminate microcracks and improve surface morphology of the film. The effects of residual stress on the magnetic properties of electrodeposited CoNiMnP hard magnetic films such as coercivity, saturation and residual magnetization are reported in this paper.

  6. Residue levels of five grain-storage-use insecticides during the production process of sorghum distilled spirits.

    PubMed

    Han, Yongtao; Huang, Baoyong; Liu, Shaowen; Zou, Nan; Yang, Juan; Zhong, Zezhi; Zhang, Xuesong; Song, Le; Qin, Yuhong; Pan, Canping

    2016-09-01

    Residue levels of dichlorvos, fenitrothion, pirimiphos-methyl, malathion and deltamethrin during sorghum distilled spirits production were examined. The analytical method for these pesticides in sorghum, fermented sorghum, rice hull and distilled spirits was validated through linearity, matrix effect, accuracy and precision, limit of quantification (LOQ) and limit of detection (LOD) parameters. The pesticide residue levels before/after each process of soaking, steaming, fermentation, and distillation were determined by gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). Results showed that soaking process could obviously reduce dichlorvos residue with 87% decrease as its high vapor pressure. The steaming process reduced pesticide residues by 42-83% mainly due to evaporation or thermal degradation. Also, the fermentation could remove pesticide residues by 40-63% in favor of biological degradation. Moreover, the distillation process was proved to be effective for decreasing the pesticide residues in distilled spirits with the processing factors lower than other processes for each pesticide. PMID:27041292

  7. Detecting ketamine in beverage residues: Application in date rape detection.

    PubMed

    Albright, Jessica A; Stevens, Sarah A; Beussman, Douglas J

    2012-05-01

    Ketamine can be used to facilitate date-rape when unknowingly spiked into a victim's beverage. If a biological sample is not available from the victim, the beverage container might be the only remaining source of forensic evidence. We present a rapid, simple analysis method for the detection of ketamine in wet or dry beverage residues based on liquid chromatography-mass spectrometry (LC-MS). Wet residues consist of the final few drops (<1 ml) in a container while dry residues are the remains once all liquid has evaporated. By using LC-MS, which readily handles aqueous samples, often no derivatization or sample extraction is needed, thus reducing analysis time and lab technician involvement. Tandem mass spectrometry (MS/MS) provides an enhancement in both selectivity and sensitivity. We have studied a range of beverages and determined limits of detection between 1.2 × 10-3 and 1.3 × 10-4 mg/ml, compared to 0.21-0.85 mg/ml used in most date-rape scenarios. This paper represents the first published report of using LC-MS/MS for the analysis of beverage residues for the presence of a date-rape drug. This method could replace the current gas chromatography-mass spectrometry (GC-MS) methods and provide a faster, more selective method for the analysis of date-rape drugs, requiring virtually no sample preparation. PMID:22114065

  8. Modeling the oxidation of methionine residues by peroxides in proteins.

    PubMed

    Chennamsetty, Naresh; Quan, Yong; Nashine, Vishal; Sadineni, Vikram; Lyngberg, Olav; Krystek, Stanley

    2015-04-01

    We report the use of molecular modeling to predict the oxidation propensity of methionine residues in proteins. Oxidation of methionine to the sulfoxide form is one of the major degradation pathways for therapeutic proteins. Oxidation can occur during production, formulation, or storage of pharmaceuticals and it often reduces or eliminates biological activity. We use a molecular model based on atomistic simulations called 2-shell water coordination number to predict the oxidation rates for several model proteins and therapeutic candidates. In addition, we implement models that are based on static and simulation average of the solvent-accessible area (SAA) for either the side chain or the sulfur atom in the methionine residue. We then compare the results from the different models against the experimentally measured relative rates of methionine oxidation. We find that both the 2-shell model and the simulation-averaged SAA models are accurate in predicting the oxidation propensity of methionine residues for the proteins tested. We also find the appropriate parameter ranges where the models are most accurate. These models have significant predictive power and can be used to enable further protein engineering or to guide formulation approaches in stabilizing the unstable methionine residues. PMID:25641333

  9. Microwave calcination for plutonium immobilization and residue stabilization

    SciTech Connect

    Harris, M.J.; Rising, T.L.; Roushey, W.J.; Sprenger, G.S.

    1995-12-01

    In the late 1980`s development was begun on a process using microwave energy to vitrify low level mixed waste sludge and transuranic mixed waste sludge generated in Building 374 at Rocky Flats. This process was shown to produce a dense, highly durable waste form. With the cessation of weapons production at Rocky Flats, the emphasis has changed from treatment of low level and TRU wastes to stabilizaiton of plutonium oxide and residues. This equipment is versatile and can be used as a heat source to calcine, react or vitrify many types of residues and oxides. It has natural economies in that it heats only the material to be treated, significantly reducing cycle times over conventional furnaces. It is inexpensive to operate in that most of the working components remain outside of any necessary contamination enclosure and therefore can easily be maintained. Limited testing has been successfully performed on cerium oxide (as a surrogate for plutonium oxide), surrogate electrorefining salts, surrogate residue sludge and residue ash. Future plans also include tests on ion exchange resins. In an attempt to further the usefullness of this technology, a mobile, self-contained microwave melting system is currently under development and expected to be operational at Rocky Flats Enviromental Technology Site by the 4th quarter of FY96.

  10. Dicofol residues in eggs and carcasses of captive American kestrels

    USGS Publications Warehouse

    Wiemeyer, Stanley N.; Clark, D.R., Jr.; Spann, J.W.; Belisle, A.A.; Bunck, C.M.

    2001-01-01

    American kestrels (Falco sparverius) were fed diets containing 0 (control), 1, 3, 10, and 30 ?g/g (wet wt) of Kelthane?. Residues of dicofol and its metabolites were then analyzed in the eggs and carcasses of females. Significant differences occurred among treatments for residues of both p,p'-dicofol and p,p'-dechlorodicofol (DCD) in both eggs and carcasses and for p,p'-dicholorbenzophenone (DCBP) in eggs. Residue concentrations increased with increasing treatment exposure. Residues of p,p'-dicofol, p,p'-DCD, and p,p'-DCBP in eggs were significantly correlated with eggshell quality parameters. Significant correlations also occurred among contaminants in eggs and for individual contaminants between eggs and carcasses. The lowest-observed-dietary-effect concentration for eggshell thinning was 3 ?g/g, whereas 1 ?g/g may be considered to be near a no-observable-adverse-effect concentration. Concentrations of dicofol in potential prey items and eggs of wild birds generally have been lower than dietary-effect concentrations or concentrations in tissues or eggs associated with eggshell thinning and reduced reproductive success.

  11. Seawater neutralization of alkaline bauxite residue and implications for revegetation.

    PubMed

    Menzies, N W; Fulton, I M; Morrell, W J

    2004-01-01

    Reaction of bauxite residue with seawater results in neutralization of alkalinity through precipitation of Mg-, Ca-, and Al-hydroxide and carbonate minerals. In batch studies, the initial pH neutralization reaction was rapid (<5 min), with further reaction continuing to reduce pH for several weeks. Reaction with seawater produced a residue pH of 8 to 8.5. Laboratory leaching column studies were undertaken to provide information on seawater neutralization of the coarse-textured fraction of the waste, residue sand (RS), under conditions comparable with those that might be applied in the field. An 0.80-m-deep column of RS was neutralized by the application of the equivalent of 2-m depth of seawater. In addition to lowering the pH and Na content of the residue, seawater neutralization resulted in the addition of substantial amounts of the plant nutrients Ca, Mg, and K to the profile. Similar results were also obtained from a field-scale assessment of neutralization. However, the accumulation of precipitate, consisting of hydrotalcite, aragonite, and pyroaurite, in the drainage system may preclude the use of in situ seawater neutralization as a routine rehabilitation practice. Following seawater neutralization, RS remains too saline to support plant growth and would require fresh water leaching before revegetation. PMID:15356249

  12. Residual Strength Prediction of Fuselage Structures with Multiple Site Damage

    NASA Technical Reports Server (NTRS)

    Chen, Chuin-Shan; Wawrzynek, Paul A.; Ingraffea, Anthony R.

    1999-01-01

    This paper summarizes recent results on simulating full-scale pressure tests of wide body, lap-jointed fuselage panels with multiple site damage (MSD). The crack tip opening angle (CTOA) fracture criterion and the FRANC3D/STAGS software program were used to analyze stable crack growth under conditions of general yielding. The link-up of multiple cracks and residual strength of damaged structures were predicted. Elastic-plastic finite element analysis based on the von Mises yield criterion and incremental flow theory with small strain assumption was used. A global-local modeling procedure was employed in the numerical analyses. Stress distributions from the numerical simulations are compared with strain gage measurements. Analysis results show that accurate representation of the load transfer through the rivets is crucial for the model to predict the stress distribution accurately. Predicted crack growth and residual strength are compared with test data. Observed and predicted results both indicate that the occurrence of small MSD cracks substantially reduces the residual strength. Modeling fatigue closure is essential to capture the fracture behavior during the early stable crack growth. Breakage of a tear strap can have a major influence on residual strength prediction.

  13. Residual stress patterns in steel welds

    SciTech Connect

    Spooner, S.; Hubbard, C.R.; Wang, X.L.; David, S.A.; Holden, T.M.; Root, J.H.; Swainson, I.

    1994-12-31

    Neutron strain scanning of residual stress is a valuable nondestructive tool for evaluation of residual stress in welds. The penetrating characteristic of neutrons permits mapping of strain patterns with a spatial resolution approaching 1mm at depths of 20mm in steels. While the overall patterns of the residual stress tensor in a weld are understood, the detailed patterns depend on welding process parameters and the effects of solid state transformation. The residual strain profiles in two multi-pass austenitic welds and a ferritic steel weld are presented. The stress-free lattice parameters within the fusion zone and the adjacent heat affected zone in the two austenitic welds show that the interpretation of residual stress from strains are affected by welding parameters. An interpretation of the residual strain pattern in the ferritic steel plate can be made using the strain measurements of a Gleeble test bar which has undergone the solid state austenite decomposition.

  14. Use of MRF residue as alternative fuel in cement production.

    PubMed

    Fyffe, John R; Breckel, Alex C; Townsend, Aaron K; Webber, Michael E

    2016-01-01

    that using MRF residue to produce SRF for use in cement kilns is likely an advantageous alternative to disposal of the residue in landfills. The use of SRF can offset fossil fuel use, reduce CO2 emissions, and divert energy-dense materials away from landfills. For this test-case, the use of SRF offset between 7700 and 8700 Mg of coal use, reduced CO2 emissions by at least 1.4%, and diverted over 7950 Mg of energy-dense materials away from landfills. In addition, emissions were reduced by at least 19% for SO2, while NOX emissions increased by between 16% and 24%. Changes in emissions of particulate matter, mercury, hydrogen chloride, and total-hydrocarbons were all less than plus or minus 2.2%, however these emissions were not measured at the cement kiln. Co-location of MRFs, SRF production facilities, and landfills can increase the benefits of SRF use even further by reducing transportation requirements. PMID:26187294

  15. Effect of electrode force condition on nugget diameter and residual stress in resistance spot welded high-strength steel sheets

    NASA Astrophysics Data System (ADS)

    Iyota, M.; Mikami, Y.; Hashimoto, T.; Taniguchi, K.; Ikeda, R.; Mochizuki, M.

    2012-08-01

    This study examines the effect of the electrode force condition on the nugget diameter and residual stress in spot welded high-strength steel sheets. Numerical simulations of spot welding were performed to examine the nugget diameter and residual stress. The results indicate that adjusting the force profile changes the current density and stress state at the spot welds. Therefore, choosing an appropriate force profile extends the nugget diameter and reduces the residual stress.

  16. Harmonic Components Based Post-Filter Design for Residual Echo Suppression

    NASA Astrophysics Data System (ADS)

    Lee, Minwoo; Lee, Yoonjae; Kim, Kihyeon; Ko, Hanseok

    In this Letter, a residual acoustic echo suppression method is proposed to enhance the speech quality of hands-free communication in an automobile environment. The echo signal is normally a human voice with harmonic characteristics in a hands-free communication environment. The proposed algorithm estimates the residual echo signal by emphasizing its harmonic components. The estimated residual echo is used to obtain the signal-to-interference ratio (SIR) information at the acoustic echo canceller output. Then, the SIR based Wiener post-filter is constructed to reduce both the residual echo and noise. The experimental results confirm that the proposed algorithm is superior to the conventional residual echo suppression algorithm in terms of the echo return loss enhancement (ERLE) and the segmental signal-to-noise ratio (SEGSNR).

  17. Air pollution control residues from waste incineration: Current UK situation and assessment of alternative technologies

    SciTech Connect

    Amutha Rani, D.; Boccaccini, A.R.; Deegan, D.; Cheeseman, C.R.

    2008-11-15

    Current disposal options for APC residues in the UK and alternative treatment technologies developed world-wide have been reviewed. APC residues are currently landfilled in the UK where they undergo in situ solidification, although the future acceptability of this option is uncertain because the EU waste acceptance criteria (WAC) introduce strict limits on leaching that are difficult to achieve. Other APC residue treatment processes have been developed which are reported to reduce leaching to below relevant regulatory limits. The Ferrox process, the VKI process, the WES-PHix process, stabilisation/solidification using cementitious binders and a range of thermal treatment processes are reviewed. Thermal treatment technologies convert APC residues combined with other wastes into inert glass or glass-ceramics that encapsulate heavy metals. The waste management industry will inevitably use the cheapest available option for treating APC residues and strict interpretation and enforcement of waste legislation is required if new, potentially more sustainable technologies are to become commercially viable.

  18. Identification of kinetically hot residues in proteins.

    PubMed Central

    Demirel, M. C.; Atilgan, A. R.; Jernigan, R. L.; Erman, B.; Bahar, I.

    1998-01-01

    A number of recent studies called attention to the presence of kinetically important residues underlying the formation and stabilization of folding nuclei in proteins, and to the possible existence of a correlation between conserved residues and those participating in the folding nuclei. Here, we use the Gaussian network model (GNM), which recently proved useful in describing the dynamic characteristics of proteins for identifying the kinetically hot residues in folded structures. These are the residues involved in the highest frequency fluctuations near the native state coordinates. Their high frequency is a manifestation of the steepness of the energy landscape near their native state positions. The theory is applied to a series of proteins whose kinetically important residues have been extensively explored: chymotrypsin inhibitor 2, cytochrome c, and related C2 proteins. Most of the residues previously pointed out to underlie the folding process of these proteins, and to be critically important for the stabilization of the tertiary fold, are correctly identified, indicating a correlation between the kinetic hot spots and the early forming structural elements in proteins. Additionally, a strong correlation between kinetically hot residues and loci of conserved residues is observed. Finally, residues that may be important for the stability of the tertiary structure of CheY are proposed. PMID:9865946

  19. Particulate residue separators for harvesting devices

    DOEpatents

    Hoskinson, Reed L.; Kenney, Kevin L.; Wright, Christopher T.; Hess, John R.

    2010-06-29

    A particulate residue separator and a method for separating a particulate residue stream may include a plenum borne by a harvesting device, and have a first, intake end and a second, exhaust end; first and second particulate residue air streams which are formed by the harvesting device and which travel, at least in part, along the plenum and in a direction of the second, exhaust end; and a baffle assembly which is located in partially occluding relation relative to the plenum, and which substantially separates the first and second particulate residue air streams.

  20. Methods of separating particulate residue streams

    DOEpatents

    Hoskinson, Reed L.; Kenney, Kevin L.; Wright, Christopher T.; Hess, J. Richard

    2011-04-05

    A particulate residue separator and a method for separating a particulate residue stream may include an air plenum borne by a harvesting device, and have a first, intake end and a second, exhaust end; first and second particulate residue air streams that are formed by the harvesting device and that travel, at least in part, along the air plenum and in a direction of the second, exhaust end; and a baffle assembly that is located in partially occluding relation relative to the air plenum and that substantially separates the first and second particulate residue air streams.

  1. Reduced Tillage in a Three Year Potato Rotation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tillage in most crop rotations is used to prepare seed-beds, control weeds and other pests, manage crop residues, reduce soil compaction, and incorporate fertilizer and pesticides. Adopting conservation tillage to reduce erosion, increase N use efficiency, and build organic matter would improve soi...

  2. Reduced bovine pancreatic trypsin inhibitor has a compact structure.

    PubMed

    Amir, D; Haas, E

    1988-12-13

    The conformation of reduced bovine pancreatic trypsin inhibitor (R-BPTI) under reducing conditions was monitored by measurements of nonradiative excitation energy-transfer efficiencies (E) between a donor probe attached to the N-terminal Arg1 residue and an acceptor attached to one of the lysine residues (15, 26, 41, or 46) [Amir, D., & Haas, E. (1987) Biochemistry 26, 2162-2175]. High-excitation energy-transfer efficiencies that approach those found in the native state were obtained for the reduced labeled BPTI derivatives in 0.5 M guanidine hydrochloride (Gdn.HCl) and 4 mM DTT. Unlike the dependence expected for a random coil chain, E does not decrease as a function of the number of residues between the labeled sites. The efficiency of energy transfer between probes attached to residues 1 and 15 in the reduced state is higher than that found for the same pair of sites in the native state or reduced unfolded (in 6 M Gdn.HCl) state. This segment also shows high dynamic flexibility. These results indicate that the overall structure of reduced BPTI under folding (but still reducing) conditions shows a high population of conformers with interprobe distances similar to those of the native state. Reduced BPTI seems to be in a molten globule state characterized by a flexible, compact structure, which probably reorganizes into the native structure when the folding is allowed to proceed under oxidizing conditions. PMID:2466482

  3. Bioethanol production from rice straw residues.

    PubMed

    Belal, Elsayed B

    2013-01-01

    A rice straw - cellulose utilizing mold was isolated from rotted rice straw residues. The efficient rice straw degrading microorganism was identified as Trichoderma reesei. The results showed that different carbon sources in liquid culture such as rice straw, carboxymethyl cellulose, filter paper, sugar cane bagasse, cotton stalk and banana stalk induced T. reesei cellulase production whereas glucose or Potato Dextrose repressed the synthesis of cellulase. T. reesei cellulase was produced by the solid state culture on rice straw medium. The optimal pH and temperature for T. reesei cellulase production were 6 and 25 °C, respectively. Rice straw exhibited different susceptibilities towards cellulase to their conversion to reducing sugars. The present study showed also that, the general trend of rice straw bioconversion with cellulase was more than the general trend by T. reesei. This enzyme effectively led to enzymatic conversion of acid, alkali and ultrasonic pretreated cellulose from rice straw into glucose, followed by fermentation into ethanol. The combined method of acid pretreatment with ultrasound and subsequent enzyme treatment resulted the highest conversion of lignocellulose in rice straw to sugar and consequently, highest ethanol concentration after 7 days fermentation with S. cerevisae yeast. The ethanol yield in this study was about 10 and 11 g.L(-1). PMID:24159309

  4. Bioethanol production from rice straw residues

    PubMed Central

    Belal, Elsayed B.

    2013-01-01

    A rice straw - cellulose utilizing mold was isolated from rotted rice straw residues. The efficient rice straw degrading microorganism was identified as Trichoderma reesei. The results showed that different carbon sources in liquid culture such as rice straw, carboxymethyl cellulose, filter paper, sugar cane bagasse, cotton stalk and banana stalk induced T. reesei cellulase production whereas glucose or Potato Dextrose repressed the synthesis of cellulase. T. reesei cellulase was produced by the solid state culture on rice straw medium. The optimal pH and temperature for T. reesei cellulase production were 6 and 25 °C, respectively. Rice straw exhibited different susceptibilities towards cellulase to their conversion to reducing sugars. The present study showed also that, the general trend of rice straw bioconversion with cellulase was more than the general trend by T. reesei. This enzyme effectively led to enzymatic conversion of acid, alkali and ultrasonic pretreated cellulose from rice straw into glucose, followed by fermentation into ethanol. The combined method of acid pretreatment with ultrasound and subsequent enzyme treatment resulted the highest conversion of lignocellulose in rice straw to sugar and consequently, highest ethanol concentration after 7 days fermentation with S. cerevisae yeast. The ethanol yield in this study was about 10 and 11 g.L−1. PMID:24159309

  5. Effects of crop residue returning on nitrous oxide emissions in agricultural soils

    NASA Astrophysics Data System (ADS)

    Shan, Jun; Yan, Xiaoyuan

    2013-06-01

    Crop residue returning is a common practice in agricultural system that consequently influences nitrous oxide (N2O) emissions. Much attention has been focused on the effects of crop residue on N2O release. However, no systematic result has yet been drawn because environmental factors among different studies vary. A meta-analysis was described to integrate 112 scientific assessments of crop residue returning on N2O emissions in this study. Results showed that crop residue returning, when averaged across all studies, had no statistically significant effect on N2O release compared with control treatments. However, the range of effects of crop residue returning on N2O emission was significantly affected by synthetic nitrogen (N) fertilizer application, type of crop residue, specific manner in which crop residue has returned, and type of land-use. N2O release was significantly inhibited by 11.7% and 27.1% (P < 0.05) when crop residue was with synthetic N fertilizer and when type of land-use was paddy, respectively. While N2O emissions were significantly enhanced by 42.1% and 23.5% (P < 0.05) when crop residue was applied alone and when type of land-use was upland, respectively. N2O emissions were likewise increased when crop residue with lower C/N ratio was used, mulching of crop residue was performed, and type of land-use was fallow. Our study provides the first quantitative analysis of crop residue returning on N2O emissions, indicating that crop residue returning has no statistically significant effect on N2O release at regional scale, and underlining that the Intergovernmental Panel on Climate Change guidelines should take the opposite effects of crop residue returning on upland and paddy into account when estimating the N2O emission factor of crop residue for different land-use types. Given that most of data are dominated by certain types of crop residue and specific application methods, more field data are required to reduce uncertainty.

  6. Partitioning Residue-derived and Residue-induced Emissions of N2O Using 15N-labelled Crop Residues

    NASA Astrophysics Data System (ADS)

    Farrell, R. E.; Carverhill, J.; Lemke, R.; Knight, J. D.

    2014-12-01

    Estimates of N2O emissions in Canada indicate that 17% of all agriculture-based emissions are associated with the decomposition of crop residues. However, research specific to the western Canadian prairies (including Saskatchewan) has shown that the N2O emission factor for N sources in this region typically ranges between 0.2 and 0.6%, which is well below the current IPCC default emission factor of 1.0%. Thus, it stands to reason that emissions from crop residues should also be lower than those calculated using the current IPCC emission factor. Current data indicates that residue decomposition, N mineralization and N2O production are affected by a number of factors such as C:N ratio and chemical composition of the residue, soil type, and soil water content; thus, a bench-scale incubation study was conducted to examine the effects of soil type and water content on N2O emissions associated with the decomposition of different crop residues. The study was carried out using soils from the Black, Dark Brown, Brown, and Gray soil zones and was conducted at both 50% and 70% water-filled pore space (WFPS); the soils were amended with 15N-labeled residues of wheat, pea, canola, and flax, or with an equivalent amount of 15N-labeled urea; 15N2O production was monitored using a Picarro G5101-i isotopic N2O analyzer. Crop residue additions to the soils resulted in both direct and indirect emissions of N2O, with residue derived emissions (RDE; measured as 15N2O) generally exceeding residue-induced emissions (RIE) at 50% WFPS—with RDEs ranging from 42% to 88% (mean = 58%) of the total N2O. Conversely, at 70% WFPS, RDEs were generally lower than RIEs—ranging from 21% to 83% (mean = 48%). Whereas both water content and soil type had an impact on N2O production, there was a clear and consistent trend in the emission factors for the residues; i.e., emissions were always greatest for the canola residue and lowest for the wheat residue and urea fertilizer; and intermediate for pea

  7. Effect of soil spectral properties on remote sensing of crop residue cover

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conservation tillage practices have been shown to improve soil structure, enhance soil organic carbon content (SOC), and reduce soil erosion. Conservation tillage practices include reduced- and no-till methods, which often leave appreciable amounts of crop residues over the soil surfaces after harv...

  8. Accounting for green vegetation and soil spectral properties to improve remote sensing of crop residue cover

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conservation tillage methods are beneficial as they disturb soil less and leaves increased crop residue cover (CRC) after planting on the soil surface. CRC helps reduce soil erosion, evaporation, and the need for tillage operations in fields. Greenhouse gas emissions are reduced to due to less fos...

  9. High residue amounts of kaolin further increase photosynthesis and fruit color in 'Empire' apple

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Kaolin (Surround WP, NovaSource, Phoenix, AZ, USA) is commonly used to reduce sunburn damage in fruit crops and to reduce heat stress on foliage. It is typically applied at rates of 3% to 6%, resulting in leaf and fruit residue levels of 1-3 g/m2. Crop modeling of the effect of kaolin on leaf/cano...

  10. Influence of Surface Properties and Impact Conditions on Adhesion of Insect Residues

    NASA Technical Reports Server (NTRS)

    Wohl, Christopher J.; Smith, Joseph G.; Connell, John W.; Siochi, Emilie J.; Doss, Jereme R.; Shanahan, Michelle H.; Penner, Ronald K.

    2015-01-01

    Insect residues can cause premature transition to turbulent flow on laminar flow airfoils. Engineered surfaces that mitigate the adhesion of insect residues provide, therefore, a route to more efficient aerodynamics and reduced fuel burn rates. Areal coverage and heights of residues depend not only on surface properties, but also on impact conditions. We report high speed photography of fruit fly impacts at different angles of inclination on a rigid aluminum surface, optical microscopy and profilometry, and contact angle goniometry to support the design of engineered surfaces. For the polyurethane and epoxy coatings studied, some of which exhibited superhydrophobicity, it was determined that impact angle and surface compositions play critical roles in the efficacy of these surfaces to reduce insect residue adhesion.

  11. Assessment of secondary crop residues. Final report

    SciTech Connect

    Ashare, E.; Leuschner, A.P.; West, C.E.; Langton, B.

    1981-03-01

    This report is the first of three reports assessing the feasibility of converting secondary agricultural residues to energy in the form of either methane gas or ethyl alcohol. Secondary agricultural residues are defined in this study as those residues resulting from biomass processing to produce primary products; e.g., whey from cheese processing, vegetable processing wastes, residues from paper pulping, etc. This report summarizes the first two phases of this study, data compilation, and evaluation. Subsequent reports will analyze the technical and economic feasibility of converting these residues to energy and the implementability of this technology. The industries for which data has been compiled in this report include vegetable, fruit, seafood, meat, poultry, and dairy processing and the pulp, paper, and paperboard industry. The data collected include raw product input, final processed product output, residue types, and quantity, residue concentration, biodegradability, seasonality of production, and geographic distribution of processing facilities. In general, these industries produce a relatively solid residue ranging in total solids concentration from 10 to 50% and a dilute liquid residue with an organic content (measured as COD or BOD) ranging from a few hundred to a few thousand mg/l. Due to the significant quantities of residues generated in each of the industries, it appears that the potential exists for generating a substantial quantity of energy. For a particular industry this quantity of energy can range from only one percent upwards to nearly thirty-five percent of the total processing energy required. The total processing energy required for the industries included in this study is approximately 2.5 quads per year. The potential energy which can be generated from these industrial residues will be 0.05 to 0.10 quads per year or approximately 2 to 4 percent of the total demand.

  12. A Benchmark Study on Casting Residual Stress

    SciTech Connect

    Johnson, Eric M.; Watkins, Thomas R; Schmidlin, Joshua E; Dutler, S. A.

    2012-01-01

    Stringent regulatory requirements, such as Tier IV norms, have pushed the cast iron for automotive applications to its limit. The castings need to be designed with closer tolerances by incorporating hitherto unknowns, such as residual stresses arising due to thermal gradients, phase and microstructural changes during solidification phenomenon. Residual stresses were earlier neglected in the casting designs by incorporating large factors of safety. Experimental measurement of residual stress in a casting through neutron or X-ray diffraction, sectioning or hole drilling, magnetic, electric or photoelastic measurements is very difficult and time consuming exercise. A detailed multi-physics model, incorporating thermo-mechanical and phase transformation phenomenon, provides an attractive alternative to assess the residual stresses generated during casting. However, before relying on the simulation methodology, it is important to rigorously validate the prediction capability by comparing it to experimental measurements. In the present work, a benchmark study was undertaken for casting residual stress measurements through neutron diffraction, which was subsequently used to validate the accuracy of simulation prediction. The stress lattice specimen geometry was designed such that subsequent castings would generate adequate residual stresses during solidification and cooling, without any cracks. The residual stresses in the cast specimen were measured using neutron diffraction. Considering the difficulty in accessing the neutron diffraction facility, these measurements can be considered as benchmark for casting simulation validations. Simulations were performed using the identical specimen geometry and casting conditions for predictions of residual stresses. The simulation predictions were found to agree well with the experimentally measured residual stresses. The experimentally validated model can be subsequently used to predict residual stresses in different cast

  13. Characterization Report on Sand, Slag, and Crucible Residues and on Fluoride Residues

    SciTech Connect

    Murray, A.M.

    1999-02-10

    This paper reports on the chemical characterization of the sand, slag, and crucible (SS and C) residues and the fluoride residues that may be shipped from the Rocky Flats Environmental Technology Site (RFETS) to Savannah River Site (SRS).

  14. 46 CFR 153.1608 - Calculation of total NLS residue and clingage NLS residue.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... MATERIALS Test and Calculation Procedures for Determining Stripping Quantity, Clingage NLS Residue, and... NLS residue for each tank is calculated by adding the stripping quantity and the clingage NLS...

  15. 46 CFR 153.1608 - Calculation of total NLS residue and clingage NLS residue.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... MATERIALS Test and Calculation Procedures for Determining Stripping Quantity, Clingage NLS Residue, and... NLS residue for each tank is calculated by adding the stripping quantity and the clingage NLS...

  16. 46 CFR 153.1608 - Calculation of total NLS residue and clingage NLS residue.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... MATERIALS Test and Calculation Procedures for Determining Stripping Quantity, Clingage NLS Residue, and... NLS residue for each tank is calculated by adding the stripping quantity and the clingage NLS...

  17. 46 CFR 153.1608 - Calculation of total NLS residue and clingage NLS residue.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... MATERIALS Test and Calculation Procedures for Determining Stripping Quantity, Clingage NLS Residue, and... NLS residue for each tank is calculated by adding the stripping quantity and the clingage NLS...

  18. Gunshot residue, ten years later.

    PubMed

    Wilber, C G; Lantz, R K; Sulik, P L

    1991-09-01

    Gunshot residues may be central to a competent reconstruction of a shooting incident. When a young boy was shot in the neck by a playmate using a .22-caliber single-action revolver, permanent paralysis from mid-thorax downward ensued. Ten years later the victim sued the importer, the vendor, the German manufacturer, and the shooter's family. Investigative reports indicated "horseplay" and questionable emergency medical team care. Depositions were contradictory. The entry wound, removed at surgery, was fixed and processed for slides. The histopathologist referred to "black pigment granules" in the wound track. The 10-year-old slides and block were retrieved. The coverslip was removed from a representative slide that was examined under the scanning, x-ray dispersive microscope. The black granules contained amounts of lead, barium, and antimony far beyond any normal range. The firing range had to have been no greater than 6-12 in (15.24-30.48 cm). The case was promptly settled out of court. PMID:1750390

  19. The Gatekeeper Residue and Beyond

    PubMed Central

    Choi, Ryan; Song, Yifan; Fox, Anna M.W.; Hillesland, Heidi K.; Zhang, Zhongsheng; Vidadala, RamaSubbaRao; Merritt, Ethan A.; Lau, Audrey O.T.; Maly, Dustin J.; Fan, Erkang; Barrett, Lynn K.; Van Voorhis, Wesley C.; Ojo, Kayode K.

    2015-01-01

    SUMMARY Specific roles of individual CDPKs vary, but in general, they mediate essential biological functions necessary for parasite's survival. A comparative analysis of the structural-activity relationships (SAR) of Neospora caninum, Eimeria tenella and Babesia bovis Calcium-dependent Protein kinases (CDPKs) together with those of Plasmodium falciparum, Cryptosporidium parvum, and Toxoplasma gondii was performed by screening against 333 Bumped kinase inhibitors (BKIs). Structural modeling and experimental data revealed that residues other than the gatekeeper influence compound-protein interactions resulting in distinct sensitivity profiles. We subsequently defined potential amino-acid structural influences within the ATP binding cavity for each orthologue necessary for consideration in the development of broad-spectrum apicomplexan CDPK inhibitors. Although the BKI library was developed for specific inhibition of glycine gatekeeper CDPKs combined with low inhibition of threonine gatekeeper human SRC kinase; some library compounds exhibit activity against serine or threonine containing CDPKs. Divergent BKI sensitivity of CDPK homologs could be explained on the basis of differences in the size and orientation of the hydrophobic pocket and specific variation at other amino-acid positions within the ATP binding cavity. In particular, BbCDPK4 and PfCDPK1 are sensitive to a larger fraction of compounds than EtCDPK1 despite the presence of threonine gatekeeper in all the three CDPKs. PMID:24927073

  20. Thermal Insulation from Hardwood Residues

    NASA Astrophysics Data System (ADS)

    Sable, I.; Grinfelds, U.; Vikele, L.; Rozenberga, L.; Zeps, M.; Luguza, S.

    2015-11-01

    Adequate heat is one of the prerequisites for human wellbeing; therefore, building insulation is required in places where the outside temperature is not suitable for living. The climate change, with its rising temperatures and longer dry periods, promotes enlargement of the regions with conditions more convenient for hardwood species than for softwood species. Birch (Betula pendula) is the most common hardwood species in Latvia. The aim of this work was to obtain birch fibres from wood residues of plywood production and to form low-density thermal insulation boards. Board formation and production was done in the presence of water; natural binder, fire retardant and fungicide were added in different concentrations. Board properties such as density, transportability or resistance to particulate loss, thermal conductivity and reaction to fire were investigated. This study included thermal insulation boards with the density of 102-120 kg/m3; a strong correlation between density and the binder amount was found. Transportability also improved with the addition of a binder, and 0.1-0.5% of the binder was the most appropriate amount for this purpose. The measured thermal conductivity was in the range of 0.040-0.043 W/(m·K). Fire resistance increased with adding the fire retardant. We concluded that birch fibres are applicable for thermal insulation board production, and it is possible to diversify board properties, changing the amount of different additives.

  1. Identification of oxidized methionine residues in peptides containing two methionine residues by derivatization and matrix-assisted laser desorption/ionization mass spectrometry.

    PubMed

    Hollemeyer, Klaus; Heinzle, Elmar; Tholey, Andreas

    2002-11-01

    Oxidation of methionine residues in peptides and proteins occurs in vivo or may be an artifact resulting from purification steps. We present a three step method for the localization of methionine sulfoxides in peptides with two methionine residues. In the first step, the N-terminus as well as other reactive side chain functions are blocked by acetylation. The resulting protected peptides are cleaved by cyanogen bromide. The cleavage does not occur at methionine sulfoxide but only at reduced methionine residues forming new amino termini. The newly formed amino group is then derivatized with a bromine containing compound in the last step of the procedure. The resulting peptide can easily be identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry using both the characteristic isotope pattern of the halogen and the metastable loss of methanesulfenic acid from oxidized residues. This procedure allows the unequivocal localization of oxidized methionines even in complex peptide mixtures. PMID:12442252

  2. Thermal Stability of Residual Stresses in Ti-6Al-4V components

    NASA Astrophysics Data System (ADS)

    Stanojevic, A.; Angerer, P.; Oberwinkler, B.

    2016-03-01

    The need for light weight design while maintaining a high safety is essential for many components, especially in the aircraft industry. Therefore, it's important to consider every aspect to reduce weight, improve fatigue life and maintain safety of crucial components. Residual stresses are a major factor which can positively influence components and fulfil all three requirements. However, due to the inconstancy of the behaviour of residual stresses during the life time of a component, residual stresses are often neglected. If the behaviour of residual stresses could be described reliably over the entire life time of a component, residual stresses could be taken into account and components could be optimized even further. Mechanical and thermal loads are the main reason for relaxation of residual stresses. This work covers the thermal stability of residual stresses in Ti-6Al-4V components. Therefore, exposure tests at raised temperatures were performed on specimens with different surface conditions. Residual stresses were measured by x-ray diffraction before and after testing. Creep tests were also carried out to describe the creep behaviour and thereby the ability for residual stress relaxation. A correlation between the creep rate and amount of relaxed stress was found. The creep behaviour of the material was described by using a combination of the Norton Power law and the Arrhenius equation. The Zener-Wert-Avrami model was used to describe the residual stress relaxation. With these models a satisfying correlation between measured and calculated data was found. Hence, the relaxation of residual stresses due to thermal load was described reliably.

  3. Solidification/stabilisation of air pollution control residues using Portland cement: Physical properties and chloride leaching.

    PubMed

    Lampris, C; Stegemann, J A; Cheeseman, C R

    2009-03-01

    Portland cement (CEMI) was used to solidify air pollution control (APC) residues from an energy-from-waste plant burning municipal solid waste. APC residue/CEMI mixes were prepared with CEMI additions ranging from 0 to 50 weight% (wt%) of total dry mass and water/solids ratios between 0.40 and 0.80. Isothermal conduction calorimetry was used to assess the effect of APC residues on the hydration of CEMI. Although up to 30wt% additions of APC residues accelerated CEMI hydration, the total heat of hydration during the initial 98h was significantly reduced. Higher levels of APC residues severely inhibited CEMI hydration. The consistence, setting time, compressive strength, porosity and chloride leaching characteristics of the solidified products were determined. As might be expected, increasing the CEMI addition and reducing the water content resulted in increased compressive strengths. All mixes achieved compressive strengths greater than 1MPa at 7 and 28days but only 50wt% samples did not show significant strength reduction when tested after immersion in water. Monolithic leaching tests indicated low physical immobilisation of chloride in the CEMI solidified APC residues, with chloride leaching in excess of relevant UK landfill waste acceptance criteria (WAC). The results of this study show that greater than 50% CEMI additions would be required to effectively treat APC residues to meet current WAC limits. PMID:18849156

  4. Persistence and effect of processing on chlorpyriphos residues in tomato (Lycopersicon esculantum Mill.).

    PubMed

    Rani, Mamta; Saini, Sunayana; Kumari, Beena

    2013-09-01

    Persistence of chlorpyriphos in tomato was studied following applications of Action 505EC at 800 and 1600 g ha(-1) with active application of chlorpyriphos as 400 and 800 g a.i. ha(-1). The average initial deposits of chlorpyriphos were 0.155 and 0.372 mg kg(-1) on tomato fruits on application of ready-mix formulation, Action 505EC at single and double dose, respectively. The residues dissipated with half- life period of 4.43 days at single dose and 4.38 days at double dose following pseudo first order kinetics.Residues of chlorpyriphos in both the doses on 0 day were below maximum residue limit (MRL) of 0.5 mg kg(-1). Processing was found very effective in reducing the residues of chlorpyriphos in tomato fruits. By washing, reduction of chlorpyriphos was in the range of 41-44 per cent. Washing followed by boiling reduced the residues from 89 to 91% whereas peeling removed residues from 62 to 64%. In soil samples, residues of chlorpyriphos reached below detectable level of 0.010 mg kg(-1) after 5 and 10 days after spray at single and double dose, respectively. PMID:23764237

  5. On-site treatment and landfilling of MSWI air pollution control residues.

    PubMed

    Lundtorp, K; Jensen, D L; Sørensen, M A; Mosbaek, H; Christensen, T H

    2003-02-28

    Air pollution control (APC) residues from municipal solid waste incineration (MSWI) are difficult to landfill due to substantial leaching of trace metals. An on-site pretreatment prior to landfilling of APC-residues was investigated in terms of bench-scale experiments with a semidry APC-residue and a fly ash. The treatment involved mixing of the residues with a ferrous sulphate solution and subsequent oxidation of the suspension. Afterwards, the suspension was spread on a dedicated landfill section and allowed to drain by gravity through the drainage system of the landfill. The wastewater from the process, collected through the drainage system, contained large concentrations of salts (Cl: 14-30 g/l, Na: 4-9 g/l, K: 5-11 g/l, Ca: 2-12 g/l) but low concentrations of trace metals (e.g. Pb: 14-100 microg/l, Cd: <2-7 microg/l). The treated residues left in the landfills were later subject to leaching by simulated rainfall. The leachate contained low concentrations of trace metals (Pb: <120 microg/l, Cd: <2 microg/l, Cr: <485 microg/l). The leachate concentrations from the treated APC-residues were substantially reduced compared to concentrations in leachate from untreated APC-residues. Particularly in the early stages of the leaching, concentrations of trace metals were reduced by up to four orders of magnitude. PMID:12573829

  6. Effect of Post-Harvest Residue on Ratoon Crops of Sugarcane Infected with Sugarcane Yellow Leaf Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sugarcane yellow leaf virus (SCYLV) is a luteovirus that causes yellow leaf of sugarcane. Previous studies in Louisiana focusing on the effect of post-harvest residue found that retention of the residue often reduces yield of subsequent ratoon crops. A field experiment to determine the potential in...

  7. High Residue Winter Cover Crops Deplete Winter Annual Weed Seed Across a Landscape in a Long-Term Tillage Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High residue conservation agriculture systems have the potential to maximize environmental benefits achieved when practicing reduced tillage. A greenhouse study was conducted in 2006 through 2008 to determine the effects of cover crop residue on weed seed density within the soil seedbank under varyi...

  8. Prediction and Optimization of Residual Stresses on Machined Surface and Sub-Surface in MQL Turning

    NASA Astrophysics Data System (ADS)

    Ji, Xia; Zou, Pan; Li, Beizhi; Rajora, Manik; Shao, Yamin; Liang, Steven Y.

    Residual stress in the machined surface and subsurface is affected by materials, machining conditions, and tool geometry and can affect the component life and service quality significantly. Empirical or numerical experiments are commonly used for determining residual stresses but these are very expensive. There has been an increase in the utilization of minimum quantity lubrication (MQL) in recent years in order to reduce the cost and tool/part handling efforts, while its effect on machined part residual stress, although important, has not been explored. This paper presents a hybrid neural network that is trained using Simulated Annealing (SA) and Levenberg-Marquardt Algorithm (LM) in order to predict the values of residual stresses in cutting and radial direction on the surface and within the work piece after the MQL face turning process. Once the ANN has successfully been trained, an optimization procedure, using Genetic Algorithm (GA), is applied in order to find the best cutting conditions in order to minimize the surface tensile residual stresses and maximize the compressive residual stresses within the work piece. The optimization results show that the usage of MQL decreases the surface tensile residual stresses and increases the compressive residual stresses within the work piece.

  9. Effect of Chinese traditional cooking on eight pesticides residue during cowpea processing.

    PubMed

    Huan, Zhibo; Xu, Zhi; Jiang, Wayne; Chen, Zhiqiang; Luo, Jinhui

    2015-03-01

    Thermal processing can concentrate residues or convert residues to more toxic metabolites in food. Chinese traditional cooking pays more attention to thermal processing and more vegetables were eaten after thermal processing. In this study, the effect of Chinese traditional cooking (washing, blanching, stir-frying, frying and combined operations) on eight pesticides residues (pyridaben, procymidone, chlorothalonil, difenoconazole, α-cypermethrin, bifenthrin, S-fenvalerate and λ-cyhalothrin) in cowpea which was one of the most important legume crops in China was examined. Result showed washing and blanching could reduce residues with low Kow while stir-frying and frying were more effective to residues with high Kow; stir-frying and frying could concentrate residues with low Kow; the residue levels in oil increased following increasing frying time and frequency especially the residues with high Kow; one metabolite studied in this paper was not detected. Blanching (5 min) followed by stir-frying (3 min) was the most effective combined operation. PMID:25306325

  10. Quality control of residual solvent content in polymeric microparticles.

    PubMed

    Dixit, Kalpana; Athawale, Rajani B; Singh, Sarabjit

    2015-01-01

    Organic solvents are the innate part of pharmaceutical industry, playing vital role in the bulk drug substance as well as finished product manufacturing. Even though they are used for various crucial purposes, they still lack therapeutic beneficial effect and can be toxic if present in unacceptable limits in final product. Hence, their concentration must be regulated in the final pharmaceutical formulation. With the major development in the market of polymeric microparticles in past few decades, drug product manufacturers are paying more attention towards the development of new techniques for reducing residual solvent content of microparticles. This article sheds light on the importance of removal of organic volatile impurities from the formulation and its regulatory aspects. It also highlights how residual solvent affects various physicochemical characteristics of polymeric microparticles and suggests certain solutions as per the current state of art for limiting organic solvent content in the final product. PMID:25560934

  11. Antioxidative and renoprotective effects of residue polysaccharides from Flammulina velutipes.

    PubMed

    Lin, Lin; Cui, Fangyuan; Zhang, Jianjun; Gao, Xia; Zhou, Meng; Xu, Nuo; Zhao, Huajie; Liu, Min; Zhang, Chen; Jia, Le

    2016-08-01

    Three extractable polysaccharides including Ac-RPS, Al-RPS and En-RPS were extracted from the residue of Flammulina velutipes and their antioxidative and renoprotective effects on STZ-induced mice were investigated. Biochemical and antioxidant analysis showed that the En-RPS had potential effects in decreasing the serum levels of CRE, BUN, ALB and GLU significantly, increasing the renal activities of SOD, CAT and GSH-Px remarkably, and reducing the renal contents of MDA prominently. Furthermore, the histopathological observations also displayed that En-RPS could alleviate kidney damage. These results demonstrated that En-RPS extracted from the residue of F. velutipes possessed potent antioxidant activities, and could be used as a promising therapeutic agent for inhibiting the progression of diabetic nephropathy. In addition, the monosaccharide compositions of these three RPS were also analyzed. PMID:27112888

  12. Effect of Pretreatment on Biomass Residue Structure and the Application of Pyrolysed and Composted Biomass Residues in Soilless Culture

    PubMed Central

    Suo, Linna; Sun, Xiangyang; Jiang, Weijie

    2013-01-01

    The changes in the structural characteristics of biomass residues during pyrolysis and composting were investigated. The biomass residues particles were prepared by pyrolysing at temperatures ranging from 350 to 400. For soilless production of the ornamental plant Anthurium andraeanum, pure sphagnum peat moss (P) has traditionally been used as the growing medium. This use of P must be reduced, however, because P is an expensive and nonrenewable resource. The current study investigated the use of biomass residues as substitutes for P in A. andraeanum production. Plants were grown for 15 months in 10 soilless media that contained different proportions of pyrolysed corn cobs (PC), composted corn cobs (C), pyrolysed garden wastes (PG), and P. Although the media altered the plant nutrient content, A. andraeanum growth, development, and yield were similar with media consisting of 50% P+50% PC, 50% P+35% PC+15% PG, and 100% P. This finding indicates that, when pyrolysed, organic wastes, which are otherwise an environmental problem, can be used to reduce the requirement for peat in the soilless culture of A. andraeanum. PMID:23704995

  13. Tank 12H residuals sample analysis report

    SciTech Connect

    Oji, L. N.; Shine, E. P.; Diprete, D. P.; Coleman, C. J.; Hay, M. S.

    2015-06-11

    The Savannah River National Laboratory (SRNL) was requested by Savannah River Remediation (SRR) to provide sample preparation and analysis of the Tank 12H final characterization samples to determine the residual tank inventory prior to grouting. Eleven Tank 12H floor and mound residual material samples and three cooling coil scrape samples were collected and delivered to SRNL between May and August of 2014.

  14. Photoelastic measurements of residual stresses for NDE

    NASA Technical Reports Server (NTRS)

    Redner, Alex S.

    1988-01-01

    Photoelastic measurements of residual strains are used extensively in the QC and inspection of transparent materials. A new method of measurements, based on Spectral Contents Analysis, is described in this paper. The method uses a personal computer for photoelastic data acquisition, eliminating personal skill and subjectivity. the new tool should make the measurements of residual strains for QC simpler and more reliable.

  15. Crop Residues: The Rest of the Story

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A recent scientific publication stated that to remove CO2 from the atmosphere, the most permanent and rapid solution would be to sink crop residues to the ocean floor where they would be buried in deep ocean sediments. However, mitigating rising atmospheric CO2 concentrations by removing crop residu...

  16. BOOSTER CHLORINATION FOR MANAGING DISINFECTANT RESIDUALS

    EPA Science Inventory

    Booster chlorination is an approach to residual maintenance in which chlorine is applied at strategic locations within the distribution system. Situations in which booster chlorination may be most effective for maintaining a residual are explained informally in the context of a ...

  17. 40 CFR 240.208 - Residue.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Residue. 240.208 Section 240.208 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES GUIDELINES FOR THE THERMAL PROCESSING OF SOLID WASTES Requirements and Recommended Procedures § 240.208 Residue....

  18. 40 CFR 240.208 - Residue.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Residue. 240.208 Section 240.208 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES GUIDELINES FOR THE THERMAL PROCESSING OF SOLID WASTES Requirements and Recommended Procedures § 240.208 Residue....

  19. 40 CFR 240.208 - Residue.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Residue. 240.208 Section 240.208 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES GUIDELINES FOR THE THERMAL PROCESSING OF SOLID WASTES Requirements and Recommended Procedures § 240.208 Residue....

  20. 40 CFR 240.208 - Residue.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Residue. 240.208 Section 240.208 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES GUIDELINES FOR THE THERMAL PROCESSING OF SOLID WASTES Requirements and Recommended Procedures § 240.208 Residue....

  1. RECOVERY OF URANIUM VALUES FROM RESIDUES

    DOEpatents

    Schaap, W.B.

    1959-08-18

    A process is described for the recovery of uranium from insoluble oxide residues resistant to repeated leaching with mineral acids. The residue is treated with gaseous hydrogen fluoride, then with hydrogen and again with hydrogen fluoride, preferably at 500 to 700 deg C, prior to the mineral acid leaching.

  2. 40 CFR 158.2290 - Residue chemistry.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Health Administration in 29 CFR 1910.1200 must accompany analytical standards. 3. Data are required if a... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Residue chemistry. 158.2290 Section... REQUIREMENTS FOR PESTICIDES Antimicrobial Pesticide Data Requirements § 158.2290 Residue chemistry. (a)...

  3. 40 CFR 158.2290 - Residue chemistry.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Health Administration in 29 CFR 1910.1200 must accompany analytical standards. 3. Data are required if a... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Residue chemistry. 158.2290 Section... REQUIREMENTS FOR PESTICIDES Antimicrobial Pesticide Data Requirements § 158.2290 Residue chemistry. (a)...

  4. CHARACTERISTICS AND TREATABILITY OF URBAN RUNOFF RESIDUALS

    EPA Science Inventory

    This study was undertaken to determine the character of urban stormwater runoff (UR) residuals as well as handling and disposal techniques. Samples of UR residuals for this study were obtained from a field-assembled sedimentation basin in Racine, WI, swirl and helical bend solids...

  5. 40 CFR 240.208 - Residue.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Residue. 240.208 Section 240.208 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES GUIDELINES FOR THE THERMAL PROCESSING OF SOLID WASTES Requirements and Recommended Procedures § 240.208 Residue....

  6. Does Bt Corn Really Produce Tougher Residues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bt corn hybrids produce insecticidal proteins that are derived from a bacterium, Bacillus thuringiensis. There have been concerns that Bt corn hybrids produce residues that are relatively resistant to decomposition. We conducted four experiments that examined the decomposition of corn residues und...

  7. Distribution of veterinary drug residues among muscles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The U.S. Food and Drug Administration sets tolerances for veterinary drug residues in muscle, but does not specify which muscle should be sampled for analysis. The goal of this research was to determine if antibiotic residue levels are dependent on muscle type. In this study, penicillin G (Pen G) d...

  8. Measurment Of Residual Stress In Ferromagnetic Materials

    NASA Technical Reports Server (NTRS)

    Namkung, Min; Yost, William T.; Kushnick, Peter W.; Grainger, John L.

    1992-01-01

    Magnetoacoustic (MAC) and magnetoacoustic emission (MAE) techniques combined to provide complete characterization of residual stresses in ferromagnetic structural materials. Combination of MAC and MAE techniques makes it possible to characterize residual tension and compression without being limited by surface conditions and unavailability of calibration standards. Significant in field of characterization of materials as well as detection of fatigue failure.

  9. Unicystic ameloblastoma arising from a residual cyst

    PubMed Central

    Mahajan, Amit D; Manjunatha, Bhari Sharanesha; Khurana, Neha M; Shah, Navin

    2014-01-01

    Intraoral swellings involving alveolar ridges in edentulous patients are clinically diagnosed as residual cysts, traumatic bone cysts, Stafne's jaw bone cavity, ameloblastoma and metastatic tumours of the jaw. This case report describes a residual cyst in a 68-year-old edentulous male patient which was enucleated and histopathologically confirmed as a unicystic ameloblastoma. PMID:25199192

  10. Crop residues: a resource for whom?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Crop residues represent an important on-farm resource, which are now being considered a harvestable commodity contributing to bio-fuel production. This review of literature looks at how crop residues contribute to soil properties and processes, water conservation and quality, on-farm forage availab...

  11. Nationwide residues of organochlorines in starlings, 1974

    USGS Publications Warehouse

    White, D.H.

    1976-01-01

    Organochlorine residues in starlings (Sturnus vulgaris) from 126 collection sites were monitored during the fall of 1974. DDE, DDT, polychlorinated biphenyls (PCB's), and benzene hexachloride were present in all samples. Dieldrin, heptachlor expoxide, hexachlorobenzene, and oxychlordane were present in approximately 97% of the samples. DDE, dieldrin, and PCB residues in starlings were significantly lower than they had been in 1972.

  12. 48 CFR 1450.104 - Residual powers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Residual powers. 1450.104 Section 1450.104 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions 1450.104 Residual powers....

  13. 48 CFR 1450.104 - Residual powers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Residual powers. 1450.104 Section 1450.104 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions 1450.104 Residual powers....

  14. 48 CFR 1450.104 - Residual powers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Residual powers. 1450.104 Section 1450.104 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions 1450.104 Residual powers....

  15. 48 CFR 1450.104 - Residual powers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 5 2012-10-01 2012-10-01 false Residual powers. 1450.104 Section 1450.104 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions 1450.104 Residual powers....

  16. 48 CFR 1450.104 - Residual powers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Residual powers. 1450.104 Section 1450.104 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR CONTRACT MANAGEMENT EXTRAORDINARY CONTRACTUAL ACTIONS AND THE SAFETY ACT Extraordinary Contractual Actions 1450.104 Residual powers....

  17. Residue management: Back to the roots

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Addressing the issues of climate change and sustainable biomass feedstocks have soil as a common theme. Managing crop residues is directly related to soil management. Understanding how soil and crop residue management interact provides insight on how to assure agricultural soil can serve as a carbon...

  18. Nationwide residues of organochlorines in starlings, 1974.

    PubMed

    White, D H

    1976-06-01

    Organochlorine residues in starlings (Sturnus vulgaris) from 126 collection sites were monitored during the fall of 1974. DDE, DDT, polychlorinated biphenyls (PCB's), and benzene hexachloride were present in all samples. Dieldrin, heptachlor expoxide, hexachlorobenzene, and oxychlordane were present in approximately 97% of the samples. DDE, dieldrin, and PCB residues in starlings were significantly lower than they had been in 1972. PMID:940731

  19. Residuals Management and Water Pollution Control Planning.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC. Office of Public Affairs.

    This pamphlet addresses the problems associated with residuals and water quality especially as it relates to the National Water Pollution Control Program. The types of residuals and appropriate management systems are discussed. Additionally, one section is devoted to the role of citizen participation in developing management programs. (CS)

  20. 46 CFR 153.1608 - Calculation of total NLS residue and clingage NLS residue.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Calculation of total NLS residue and clingage NLS residue. 153.1608 Section 153.1608 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... MATERIALS Test and Calculation Procedures for Determining Stripping Quantity, Clingage NLS Residue,...

  1. Residuals and the Residual-Based Statistic for Testing Goodness of Fit of Structural Equation Models

    ERIC Educational Resources Information Center

    Foldnes, Njal; Foss, Tron; Olsson, Ulf Henning

    2012-01-01

    The residuals obtained from fitting a structural equation model are crucial ingredients in obtaining chi-square goodness-of-fit statistics for the model. The authors present a didactic discussion of the residuals, obtaining a geometrical interpretation by recognizing the residuals as the result of oblique projections. This sheds light on the…

  2. Residual stress measurement in YBCO thin films.

    SciTech Connect

    Cheon, J. H.; Singh, J. P.

    2002-05-13

    Residual stress in YBCO films on Ag and Hastelloy C substrates was determined by using 3-D optical interferometry and laser scanning to measure the change in curvature radius before and after film deposition. The residual stress was obtained by appropriate analysis of curvature measurements. Consistent with residual thermal stress calculations based on the thermal expansion coefficient mismatch between the substrates and YBCO film, the measured residual stress in the YBCO film on Hastelloy C substrate was tensile, while it was compressive on the Ag substrate. The stress values measured by the two techniques were generally in good agreement, suggesting that optical interferometry and laser scanning have promise for measuring residual stresses in thin films.

  3. NASA's Microgravity Fluid Physics Program: Tolerability to Residual Accelerations

    NASA Technical Reports Server (NTRS)

    Skarda, J. Raymond

    1998-01-01

    An overview of the NASA microgravity fluid physics program is presented. The necessary quality of a reduced-gravity environment in terms of tolerable residual acceleration or g levels is a concern that is inevitably raised for each new microgravity experiment. Methodologies have been reported in the literature that provide guidance in obtaining reasonable estimates of residual acceleration sensitivity for a broad range of fluid physics phenomena. Furthermore, a relatively large and growing database of microgravity experiments that have successfully been performed in terrestrial reduced gravity facilities and orbiting platforms exists. Similarity of experimental conditions and hardware, in some cases, lead to new experiments adopting prior experiments g-requirements. Rationale applied to other experiments can, in principle, be a valuable guide to assist new Principal Investigators, PIs, in determining the residual acceleration tolerability of their flight experiments. The availability of g-requirements rationale from prior (mu)g experiments is discussed. An example of establishing g tolerability requirements is demonstrated, using a current microgravity fluid physics flight experiment. The Fluids and Combustion Facility (FCF) which is currently manifested on the US Laboratory of the International Space Station (ISS) will provide opportunities for fluid physics and combustion experiments throughout the life of the ISS. Although the FCF is not intended to accommodate all fluid physics experiments, it is expected to meet the science requirements of approximately 80% of the new PIs that enter the microgravity fluid physics program. The residual acceleration requirements for the FCF fluid physics experiments are based on a set of fourteen reference fluid physics experiments which are discussed.

  4. Residual macrovascular risk in 2013: what have we learned?

    PubMed Central

    2014-01-01

    Cardiovascular disease poses a major challenge for the 21st century, exacerbated by the pandemics of obesity, metabolic syndrome and type 2 diabetes. While best standards of care, including high-dose statins, can ameliorate the risk of vascular complications, patients remain at high risk of cardiovascular events. The Residual Risk Reduction Initiative (R3i) has previously highlighted atherogenic dyslipidaemia, defined as the imbalance between proatherogenic triglyceride-rich apolipoprotein B-containing-lipoproteins and antiatherogenic apolipoprotein A-I-lipoproteins (as in high-density lipoprotein, HDL), as an important modifiable contributor to lipid-related residual cardiovascular risk, especially in insulin-resistant conditions. As part of its mission to improve awareness and clinical management of atherogenic dyslipidaemia, the R3i has identified three key priorities for action: i) to improve recognition of atherogenic dyslipidaemia in patients at high cardiometabolic risk with or without diabetes; ii) to improve implementation and adherence to guideline-based therapies; and iii) to improve therapeutic strategies for managing atherogenic dyslipidaemia. The R3i believes that monitoring of non-HDL cholesterol provides a simple, practical tool for treatment decisions regarding the management of lipid-related residual cardiovascular risk. Addition of a fibrate, niacin (North and South America), omega-3 fatty acids or ezetimibe are all options for combination with a statin to further reduce non-HDL cholesterol, although lacking in hard evidence for cardiovascular outcome benefits. Several emerging treatments may offer promise. These include the next generation peroxisome proliferator-activated receptorα agonists, cholesteryl ester transfer protein inhibitors and monoclonal antibody therapy targeting proprotein convertase subtilisin/kexin type 9. However, long-term outcomes and safety data are clearly needed. In conclusion, the R3i believes that ongoing trials with

  5. Residual Strength Analyses of Monolithic Structures

    NASA Technical Reports Server (NTRS)

    Forth, Scott (Technical Monitor); Ambur, Damodar R. (Technical Monitor); Seshadri, B. R.; Tiwari, S. N.

    2003-01-01

    Finite-element fracture simulation methodology predicts the residual strength of damaged aircraft structures. The methodology uses the critical crack-tip-opening-angle (CTOA) fracture criterion to characterize the fracture behavior of the material. The CTOA fracture criterion assumes that stable crack growth occurs when the crack-tip angle reaches a constant critical value. The use of the CTOA criterion requires an elastic- plastic, finite-element analysis. The critical CTOA value is determined by simulating fracture behavior in laboratory specimens, such as a compact specimen, to obtain the angle that best fits the observed test behavior. The critical CTOA value appears to be independent of loading, crack length, and in-plane dimensions. However, it is a function of material thickness and local crack-front constraint. Modeling the local constraint requires either a three-dimensional analysis or a two-dimensional analysis with an approximation to account for the constraint effects. In recent times as the aircraft industry is leaning towards monolithic structures with the intention of reducing part count and manufacturing cost, there has been a consistent effort at NASA Langley to extend critical CTOA based numerical methodology in the analysis of integrally-stiffened panels.In this regard, a series of fracture tests were conducted on both flat and curved aluminum alloy integrally-stiffened panels. These flat panels were subjected to uniaxial tension and during the test, applied load-crack extension, out-of-plane displacements and local deformations around the crack tip region were measured. Compact and middle-crack tension specimens were tested to determine the critical angle (wc) using three-dimensional code (ZIP3D) and the plane-strain core height (hJ using two-dimensional code (STAGS). These values were then used in the STAGS analysis to predict the fracture behavior of the integrally-stiffened panels. The analyses modeled stable tearing, buckling, and crack

  6. POST-OPERATIONAL TREATMENT OF RESIDUAL NA COOLLANT IN EBR-2 USING CARBONATION

    SciTech Connect

    Sherman, S.; Knight, C.

    2011-03-08

    safety standpoint, the inventory of residual sodium in these systems was greatly reduced by using the carbonation process. From a regulatory standpoint, the process was not able to achieve deactivation of all residual sodium, and other more aggressive measures will be needed if the remaining residual sodium must also be deactivated to meet the requirements of the existing environmental permit. This chapter provides a project history and technical summary of the carbonation of EBR-II residual sodium. Options for future treatment are also discussed.

  7. Gunshot residue preservation in seawater.

    PubMed

    Lindström, Anne-Christine; Hoogewerff, Jurian; Athens, Josie; Obertova, Zuzana; Duncan, Warwick; Waddell, Neil; Kieser, Jules

    2015-08-01

    Little is known about the persistence of gunshot residue (GSR) in soft tissue and bones during decomposition in marine environments. For a better understanding, qualitative and quantitative data were obtained on GSR retention on soft tissue and bony gunshot wounds (GSWs). A quantity of 36 fleshed and 36 defleshed bovine ribs were shot at contact range with 0.22 calibre hollow point ammunition using a Stirling 0.22 calibre long rifle. Bone specimens in triplicate were placed in three environments: submerged, intertidal and in supralittoral zone. Sets of triplicates were recovered on day 3, 10, 24 and 38, and analysed with scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDX), and inductive coupled plasma mass spectrometry (ICP-MS). The SEM-EDX recorded GSR-indicative particles surrounding the bullet entrance on all bone types (fleshed and defleshed) in all environments throughout the study. GSR-unique particles were only detected on the supralittoral bones. The ICP-MS analysis showed faster GSR loss on submerged than intertidal and supralittoral defleshed specimens. Fleshed specimens showed a faster GSR loss on intertidal than submerged and supralittoral specimens. In conclusion, the GSR disappeared faster from submerged and intertidal than non-submerged specimens. The difference of detection of GSR between analysed specimens (defleshed versus fleshed) disappeared upon defleshing. This study highlights the potential of finding evidence of GSR in a submerged body and the potential of microscopic and analytical methods for examining suspected GSW in highly decomposed bodies in marine habitats. PMID:26115226

  8. Reduced discretization error in HZETRN

    SciTech Connect

    Slaba, Tony C.; Blattnig, Steve R.; Tweed, John

    2013-02-01

    The deterministic particle transport code HZETRN is an efficient analysis tool for studying the effects of space radiation on humans, electronics, and shielding materials. In a previous work, numerical methods in the code were reviewed, and new methods were developed that further improved efficiency and reduced overall discretization error. It was also shown that the remaining discretization error could be attributed to low energy light ions (A < 4) with residual ranges smaller than the physical step-size taken by the code. Accurately resolving the spectrum of low energy light particles is important in assessing risk associated with astronaut radiation exposure. In this work, modifications to the light particle transport formalism are presented that accurately resolve the spectrum of low energy light ion target fragments. The modified formalism is shown to significantly reduce overall discretization error and allows a physical approximation to be removed. For typical step-sizes and energy grids used in HZETRN, discretization errors for the revised light particle transport algorithms are shown to be less than 4% for aluminum and water shielding thicknesses as large as 100 g/cm{sup 2} exposed to both solar particle event and galactic cosmic ray environments.

  9. Fasting, but Not Aging, Dramatically Alters the Redox Status of Cysteine Residues on Proteins in Drosophila melanogaster

    PubMed Central

    Menger, Katja E.; James, Andrew M.; Cochemé, Helena M.; Harbour, Michael E.; Chouchani, Edward T.; Ding, Shujing; Fearnley, Ian M.; Partridge, Linda; Murphy, Michael P.

    2015-01-01

    Summary Altering the redox state of cysteine residues on protein surfaces is an important response to environmental challenges. Although aging and fasting alter many redox processes, the role of cysteine residues is uncertain. To address this, we used a redox proteomic technique, oxidative isotope-coded affinity tags (OxICAT), to assess cysteine-residue redox changes in Drosophila melanogaster during aging and fasting. This approach enabled us to simultaneously identify and quantify the redox state of several hundred cysteine residues in vivo. Cysteine residues within young flies had a bimodal distribution with peaks at ∼10% and ∼85% reversibly oxidized. Surprisingly, these cysteine residues did not become more oxidized with age. In contrast, 24 hr of fasting dramatically oxidized cysteine residues that were reduced under fed conditions while also reducing cysteine residues that were initially oxidized. We conclude that fasting, but not aging, dramatically alters cysteine-residue redox status in D. melanogaster. PMID:26095360

  10. Structure-based identification of catalytic residues

    PubMed Central

    Yahalom, Ran; Reshef, Dan; Wiener, Ayana; Frankel, Sagiv; Kalisman, Nir; Lerner, Boaz; Keasar, Chen

    2011-01-01

    The identification of catalytic residues is an essential step in functional characterization of enzymes. We present a purely structural approach to this problem, which is motivated by the difficulty of evolution-based methods to annotate structural genomics targets that have few or no homologs in the databases. Our approach combines a state-of-the-art support vector machine (SVM) classifier with novel structural features that augment structural clues by spatial averaging and Z-scoring. Special attention is paid to the class imbalance problem that stems from the overwhelming number of non-catalytic residues in enzymes compared to catalytic residues. This problem is tackled by: 1) optimizing the classifier to maximize a performance criterion that considers both type I and type II errors in the classification of catalytic and non-catalytic residues; 2) under-sampling non-catalytic residues before SVM training; and 3) during SVM training, penalizing errors in learning catalytic residues more than errors in learning non-catalytic residues. Tested on four enzyme datasets – one specifically designed by us to mimic the structural genomics scenario and three previously-evaluated datasets – our structure-based classifier is never inferior to similar structure-based classifiers and comparable to classifiers that use both structural and evolutionary features. In addition to evaluation of the performance of catalytic residue identification, we also present detailed case studies on three proteins. This analysis suggests that many false positive predictions may correspond to binding sites and other functional residues. A web server that implements the method, our own-designed database, and the source code of the programs are publicly available at http://www.cs.bgu.ac.il/~meshi/functionPrediction. PMID:21491495

  11. Structure-based identification of catalytic residues.

    PubMed

    Yahalom, Ran; Reshef, Dan; Wiener, Ayana; Frankel, Sagiv; Kalisman, Nir; Lerner, Boaz; Keasar, Chen

    2011-06-01

    The identification of catalytic residues is an essential step in functional characterization of enzymes. We present a purely structural approach to this problem, which is motivated by the difficulty of evolution-based methods to annotate structural genomics targets that have few or no homologs in the databases. Our approach combines a state-of-the-art support vector machine (SVM) classifier with novel structural features that augment structural clues by spatial averaging and Z scoring. Special attention is paid to the class imbalance problem that stems from the overwhelming number of non-catalytic residues in enzymes compared to catalytic residues. This problem is tackled by: (1) optimizing the classifier to maximize a performance criterion that considers both Type I and Type II errors in the classification of catalytic and non-catalytic residues; (2) under-sampling non-catalytic residues before SVM training; and (3) during SVM training, penalizing errors in learning catalytic residues more than errors in learning non-catalytic residues. Tested on four enzyme datasets, one specifically designed by us to mimic the structural genomics scenario and three previously evaluated datasets, our structure-based classifier is never inferior to similar structure-based classifiers and comparable to classifiers that use both structural and evolutionary features. In addition to the evaluation of the performance of catalytic residue identification, we also present detailed case studies on three proteins. This analysis suggests that many false positive predictions may correspond to binding sites and other functional residues. A web server that implements the method, our own-designed database, and the source code of the programs are publicly available at http://www.cs.bgu.ac.il/∼meshi/functionPrediction. PMID:21491495

  12. [Occurrence of pesticide residues in raspberries in 2000-2005].

    PubMed

    Sadło, Stanisław; Szpyrka, Ewa; Rogozińska, Krystyna; Rupar, Julian; Kuźmenko, Arletta

    2007-01-01

    The aim of this paper was to present occurrence of pesticide residues in raspberries in 2000-2005. Gas chromatographic and spectroscopy methods were used. The most frequently found were tolylfluanid residues (43% of the analysed samples), procymidone residues (33%), pyrimethanil residues (15%), ethylenebisdithiocarbamates (EBDC) residues (8%) and iprodione residues (5%), while insecticides (mainly synthetic pyrethroids) cypermethrin residues (6%) and bifenthrin (4%). In 8 % of analysed samples EBDC residues exceeded the national Maximum Residue Level established for raspberries. On relatively the highest level EBDC occurred. PMID:18246655

  13. Characterization of biomass residues and their amendment effects on water sorption and nutrient leaching in sandy soil.

    PubMed

    Wang, Letian; Tong, Zhaohui; Liu, Guodong; Li, Yuncong

    2014-07-01

    In this study, we evaluated the efficiency of two types of biomass residues (fermentation residues from a bioethanol process, FB; brown mill residues from a papermaking process, BM) as amendments for a sandy soil. The characteristics of these residues including specific surface areas, morphologies and nutrient sorption capacity were measured. The effects of biorefinery residues on water and nutrient retention were investigated in terms of different particle sizes and loadings. The results indicated that bio-based wastes FB and BM were able to significantly improve water and nutrient retention of sandy soil. The residues with larger surface areas had better water and nutrient retention capability. Specifically, in the addition of 10% loading, FB and BM was able to improve water retention by approximately 150% and 300%, while reduce 99% of ammonium and phosphate concentration in the leachate compare to the soil control, respectively. PMID:24529394

  14. Properties of aromatic residues in ferricytochrome c3 of desulforvibrio vulgaris Miyazaki F studied by 1H NMR

    NASA Astrophysics Data System (ADS)

    Park, Jang-Su; Enoki, Minoru; Ohbu, Ayako; Fan, Kejung; Niki, Katsumi; Akutsu, Hideo; Kyogoku, Yoshimasa

    1991-01-01

    Conditions for the specific labelling of the tetrahaeme protein cytochrome c3 of Desulfovibrio vulgaris Miyazaki F during culture of this sulphate-reducing bacterium in a minimal medium were established. Phenylalanine and tyrosine residues were specifically deuterated at more than 85% efficiency. Cytochrome c3 has nine histidine, three tyrosine and two phenylalamine residues. Eight histidine imidazoles are ligated to four haeme groups. Using the deuterated cytochrome c3, aromatic proton signals of phenylalanine and tyrosine residues in the fully oxidized state were identified. However, the signals of one phenylalanine residue were missing and this was tentatively assigned to Phe20. The aromatic proton signals of His67 were also assigned p2H titration. Its pk1 was much higher than that for the free histidine residue. No tyrosine residue was ionized up to p2H 12.

  15. A techno-economic analysis of using mobile distributed pyrolysis facilities to deliver a forest residue resource.

    PubMed

    Brown, Duncan; Rowe, Andrew; Wild, Peter

    2013-12-01

    Distributed mobile conversion facilities using either fast pyrolysis or torrefaction processes can be used to convert forest residues to more energy dense substances (bio-oil, bio-slurry or torrefied wood) that can be transported as feedstock for bio-fuel facilities. Results show that the levelised delivered cost of a forest residue resource using mobile facility networks can be lower than using conventional woodchip delivery methods under appropriate conditions. Torrefied wood is the lowest cost pathway of delivering a forest residue resource when using mobile facilities. Cost savings occur against woodchip delivery for annual forest residue harvests above 2.5 million m(3) or when transport distances greater than 300 km are required. Important parameters that influence levelised delivered costs are transport distances (forest residue spatial density), haul cost factors, and initial moisture content of forest residues. Relocating mobile facilities can be optimised for lowest cost delivery as transport distances of raw biomass are reduced. PMID:24185419

  16. Residual stresses in injection molded products

    NASA Astrophysics Data System (ADS)

    Jansen, K. M. B.

    2015-12-01

    During the molding process residual stresses are formed due to thermal contraction during cooling as well as the local pressure history during solidification. In this paper a simple analytical model is reviewed which relates residual stresses, product shrinkage as well as warpage to the temperature and pressure histories during molding. Precise excimer laser layer removal measurements were performed to verify the predicted residual stress distributions. In addition, detailed shrinkage and warpage measurements on a large series of polymers and for different molding conditions were performed and are shown to compare well with the model predictions.

  17. Simple approach for ranking structure determining residues

    PubMed Central

    Luna-Martínez, Oscar D.; Vidal-Limón, Abraham; Villalba-Velázquez, Miryam I.; Sánchez-Alcalá, Rosalba; Garduño-Juárez, Ramón; Uversky, Vladimir N.

    2016-01-01

    Mutating residues has been a common task in order to study structural properties of the protein of interest. Here, we propose and validate a simple method that allows the identification of structural determinants; i.e., residues essential for preservation of the stability of global structure, regardless of the protein topology. This method evaluates all of the residues in a 3D structure of a given globular protein by ranking them according to their connectivity and movement restrictions without topology constraints. Our results matched up with sequence-based predictors that look up for intrinsically disordered segments, suggesting that protein disorder can also be described with the proposed methodology. PMID:27366642

  18. Diazinon residues in insects from sprayed tobacco

    USGS Publications Warehouse

    Stromborg, K.L.; Beyer, W.N.; Kolbe, E.

    1982-01-01

    Pooled samples of tobacco hornworms collected from a field sprayed with 0.84 kg/ha of diazinon were analyzed for residues at various intervals after application. No residues of the toxic metabolite diazoxon were detected (sensitivity 0.5 ppm) in any sample. Only one sample exceeded 1.0 ppm of the parent compound and was collected 4 hours after spraying. Residues declined over time (P<0.01) and none were detected (sensitivity 0.1 ppm) 18 days after spraying. the potential hazard to birds eating these insects appeared to be minimal.

  19. Identification of residues by infrared spectroscopy

    SciTech Connect

    Barber, T.E.; Ayala, N.L.; Jin, Hong; Drumheller, C.T.

    1997-12-31

    Mid-infrared spectroscopy of surfaces can be a very powerful technique for the qualitative and quantitative analysis of surface residues. The goal of this work was to study the application of diffuse reflectance mid-infrared spectroscopy to the identification of pesticide, herbicide, and explosive residues on surfaces. A field portable diffuse reflectance spectrometer was used to collect the mid-infrared spectra of clean surfaces and contaminated surfaces. These spectra were used as calibration sets to develop automated data analysis to classify or to identify residues on samples. In this presentation, the instrumentation and data process algorithms will be discussed.

  20. Simple approach for ranking structure determining residues.

    PubMed

    Luna-Martínez, Oscar D; Vidal-Limón, Abraham; Villalba-Velázquez, Miryam I; Sánchez-Alcalá, Rosalba; Garduño-Juárez, Ramón; Uversky, Vladimir N; Becerril, Baltazar

    2016-01-01

    Mutating residues has been a common task in order to study structural properties of the protein of interest. Here, we propose and validate a simple method that allows the identification of structural determinants; i.e., residues essential for preservation of the stability of global structure, regardless of the protein topology. This method evaluates all of the residues in a 3D structure of a given globular protein by ranking them according to their connectivity and movement restrictions without topology constraints. Our results matched up with sequence-based predictors that look up for intrinsically disordered segments, suggesting that protein disorder can also be described with the proposed methodology. PMID:27366642

  1. Influence of water treatment residuals on dewaterability of wastewater biosolids.

    PubMed

    Taylor, Malcolm; Elliott, Herschel A

    2013-01-01

    Co-dewatering of water treatment residuals (WTR) and wastewater biosolids can potentially benefit municipalities by reducing processing equipment and costs. This study investigated dewaterability (using capillary suction time, CST) of combined alum residuals (Al-WTR) and anaerobically digested biosolids at various blending ratios (BR), defined as the mass ratio of WTR to biosolids on a dry solids basis. Without polymer addition, the CST was 160 s for a BR of 0.75 compared with 355 s for the biosolids alone. The optimum polymer dose (OPD), defined as the polymer dose yielding CST of 20 s, was reduced from 20.6 g kg(-1) dry solids for the biosolids alone to 16.3 and 12.6 g kg(-1) when BR was 0.75 and 1.5, respectively. Precipitated Al hydrous oxides in the WTR likely caused flocculation of the biosolids particles through heterocoagulation or charge neutralization. The solids contents of the blended materials and biosolids at their respective OPDs were not statistically different (α = 0.05) following dewatering by a belt-filter press. We conclude addition of Al-WTR improved biosolids dewaterability and reduced polymer dosage. In practice, the extent of these benefits may be limited by the quantity of WTR produced relative to the amount of wastewater solids generated by a municipality. PMID:23128637

  2. Effects of washing, peeling, storage, and fermentation on residue contents of carbaryl and mancozeb in cucumbers grown in greenhouses.

    PubMed

    Saeedi Saravi, S S; Shokrzadeh, M

    2016-06-01

    Cucumbers grown in two different greenhouses were exposed to mancozeb and carbaryl at different times. The effects of 10-day preharvest period, water and detergent washing, peeling, predetermined storage period at 4°C (refrigeration), and fermentation on the reduction of residue levels in the plant tissues were investigated. Mancozeb and carbaryl residues in cucumbers were determined by gas chromatography-electron capture detection. Results showed that residue levels in samples, which were collected after 10 days following the pesticide application, were significantly lower than the samples collected after 2 h subsequent to the pesticide application. The culinary applications were effective in reducing the residue levels of the pesticides in cucumbers. As a result, non-fermentative pickling in sodium chloride and acetic acid was the most effective way to reduce the mancozeb and carbaryl residues of the cucumbers. PMID:25342670

  3. Venous gas embolism - Time course of residual pulmonary intravascular bubbles

    NASA Technical Reports Server (NTRS)

    Butler, B. D.; Luehr, S.; Katz, J.

    1989-01-01

    A study was carried out to determine the time course of residual pulmonary intravascular bubbles after embolization with known amounts of venous air, using an N2O challenge technique. Attention was also given to the length of time that the venous gas emboli remained as discrete bubbles in the lungs with 100 percent oxygen ventilation. The data indicate that venous gas emboli can remain in the pulmonary vasculature as discrete bubbles for periods lasting up to 43 + or - 10.8 min in dogs ventilated with oxygen and nitrogen. With 100 percent oxygen ventilation, these values are reduced significantly to 19 + or - 2.5 min.

  4. Desalination of geothermal brines by means of combustion residues

    SciTech Connect

    Pernklau, E.; Althaus, E.

    1986-01-01

    Geothermal brines with high salinity are frequently encountered. Their commercial utilization, e.g. for heat recovery, is handicapped by scaling and disposal problems. A simple method for attaining a significant reduction of salinity would solve this problem. This paper examines the possibility of desalinating by entrapment of sodium chloride in sodalite. Sodalite is formed by the reaction of a hot brine with materials containing aluminum and silicon, e.g. combustion residues. The authors have reduced the sodium chloride content of a model brine in this manner.

  5. Residual mode filters and adaptive control in large space structures

    NASA Technical Reports Server (NTRS)

    Davidson, Roger A.; Balas, Mark J.

    1989-01-01

    One of the most difficult problems in controlling large systems and structures is compensating for the destructive interaction which can occur between the reduced-order model (ROM) of the plant, which is used by the controller, and the unmodeled dynamics of the plant, often called the residual modes. The problem is more significant in the case of large space structures because their naturally light damping and high performance requirements lead to more frequent, destructive residual mode interaction (RMI). Using the design/compensation technique of residual mode filters (RMF's), effective compensation of RMI can be accomplished in a straightforward manner when using linear controllers. The use of RMF's has been shown to be effective for a variety of large structures, including a space-based laser and infinite dimensional systems. However, the dynamics of space structures is often uncertain and may even change over time due to on-orbit erosion from space debris and corrosive chemicals in the upper atmosphere. In this case, adaptive control can be extremely beneficial in meeting the performance requirements of the structure. Adaptive control for large structures is also based on ROM's and so destructive RMI may occur. Unfortunately, adaptive control is inherently nonlinear, and therefore the known results of RMF's cannot be applied. The purpose is to present the results of new research showing the effects of RMI when using adaptive control and the work which will hopefully lead to RMF compensation of this problem.

  6. Partial stream digestion of residual municipal solid waste.

    PubMed

    De Baere, L

    2008-01-01

    Anaerobic digestion of residual municipal solid waste (MSW) has become more important than the digestion of source separated biowaste. More than 52% of the capacity available in Europe was designed for digestion of residual municipal waste by the end of 2006, while this was only 13% in 1998. Partial digestion of residual waste organics, by which only a part of the organics is digested, has been implemented to reduce the need for dewatering and subsequent wastewater treatment. The digestate coming from part of the organics is immediately mixed with the non-digested organic fraction. This organic fraction is drier and still contains a lot of energy which can be used to dry the digestate during the aerobic composting of the mixture of digested and undigested organics. Such a MBT-plant has been operating for over a year whereby 2/3 of the organics (including sludge cake) are digested (25,000 t/year) and mixed after digestion with the remaining 1/3 of the organics. Biogas production averages 125.7 Nm2 per ton fed and contained 56.2% of methane. The mixture of digestate and non-digested organics is aerated in tunnels during 4 to 6 weeks. The stabilized end product is landfilled, meeting the stringent German standards for inert landfills. By using a dry fermentation able to produce a digestate at 35% solids, there is no need for dewatering the digestate so that no wastewater is produced. PMID:18441435

  7. Fate of asphaltenes during hydroprocessing of heavy petroleum residues

    SciTech Connect

    Stanislaus, A.; Absi-Halabi, M.; Khan, Z.

    1994-12-31

    Formation of coke like sediments or particulates is a serious problem in the hydroprocessing of heavy residues for high conversion. The sediments can cause both operability problems and rapid catalyst deactivation. The macromolecules of the heavy feedstocks such as asphaltenes are believed to contribute significantly to sediment formation and coke deposition. As part of an extensive research program on the factors which influence sludge or solids formation during residue hydroprocessing, the authors have examined the nature of changes that take place in the characteristics of the asphaltenic fraction of Kuwait vacuum residue under different operating conditions. The studies revealed that sediment formation is the result of reduction in solubilization efficiency of asphaltenes in the product medium compared with feedstock. Molecular size distribution of the product asphaltenes showed that operating at high temperatures enhanced depolymerization and fragmentation of asphaltenes to low molecular weight materials. A portion of the low molecular weight asphaltene fragments with relatively low H/C ratio resisted further cracking even at high temperatures and led to the formation of coke like sediments. Large pore catalysts were observed to reduce the problem of sediments formation. The role of catalyst pore size on asphaltenes conversion is discussed.

  8. Washing of Rocky Flats Combustible Residues (Conducted March - May 1995)

    SciTech Connect

    Mary E. Barr; Ann R. Schake; David A. Romero; Gordon D. Jarvinen

    1999-03-01

    The scope of this project is to determine the feasibility of washing plutonium-containing combustible residues using ultrasonic disruption as a method for dislodging particulate. Removal of plutonium particulate and, to a lesser extent, solubilized plutonium from the organic substrate should substantially reduce potential fire, explosion or radioactive release hazards due to radiolytic hydrogen generation or high flammability. Tests were conducted on polypropylene filters which were used as pre-filters in the rich-residue ion-exchange process at the Los Alamos Plutonium Facility. These filters are similar to the Ful-Flo{reg_sign} cartridges used at Rocky Flats that make up a substantial fraction of the combustible residues with the highest hazard rating. Batch experiments were run on crushed filter material in order to determine the amount of Pu removed by stirring, stirring and sonication, and stirring and sonication with the introduction of Pu-chelating water-soluble polymers or surfactants. Significantly more Pu is removed using sonication and sonication with chelators than is removed with mechanical stirring alone.

  9. Engineered Surfaces for Mitigation of Insect Residue Adhesion

    NASA Technical Reports Server (NTRS)

    Siochi, Emilie J.; Smith, Joseph G.; Wohl, Christopher J.; Gardner, J. M.; Penner, Ronald K.; Connell, John W.

    2013-01-01

    Maintenance of laminar flow under operational flight conditions is being investigated under NASA s Environmentally Responsible Aviation (ERA) Program. Among the challenges with natural laminar flow is the accretion of residues from insect impacts incurred during takeoff or landing. Depending on air speed, temperature, and wing structure, the critical residue height for laminar flow disruption can be as low as 4 microns near the leading edge. In this study, engineered surfaces designed to minimize insect residue adhesion were examined. The coatings studied included chemical compositions containing functional groups typically associated with abhesive (non-stick) surfaces. To reduce surface contact by liquids and enhance abhesion, the engineered surfaces consisted of these coatings doped with particulate additives to generate random surface topography, as well as coatings applied to laser ablated surfaces having precision patterned topographies. Performance evaluation of these surfaces included contact angle goniometry of pristine coatings and profilometry of surfaces after insect impacts were incurred in laboratory scale tests, wind tunnel tests and flight tests. The results illustrate the complexity of designing antifouling surfaces for effective insect contamination mitigation under dynamic conditions and suggest that superhydrophobic surfaces may not be the most effective solution for preventing insect contamination on aircraft wing leading edges.

  10. Microscopic theory of the residual surface resistivity of Rashba electrons

    NASA Astrophysics Data System (ADS)

    Bouaziz, Juba; Lounis, Samir; Blügel, Stefan; Ishida, Hiroshi

    2016-07-01

    A microscopic expression of the residual electrical resistivity tensor is derived in linear response theory for Rashba electrons scattering at a magnetic impurity with cylindrical or noncylindrical potential. The behavior of the longitudinal and transversal residual resistivity is obtained analytically and computed for an Fe impurity at the Au(111) surface. We studied the evolution of the resistivity tensor elements as a function of the Rashba spin-orbit strength and the magnetization direction of the impurity. We found that the absolute values of longitudinal resistivity reduce with increasing spin-orbit strength of the substrate and that the scattering of the conduction electrons at magnetic impurities with magnetic moments pointing in directions not perpendicular to the surface plane produce a planar Hall effect and an anisotropic magnetoresistance even if the impurity carries no spin-orbit interaction. Functional forms are provided describing the anisotropy of the planar Hall effect and the anisotropic magnetoresistance with respect to the direction of the impurity moment. In the limit of no spin-orbit interaction and a nonmagnetic impurity of cylindrical symmetry, the expression of the residual resistivity of a two-dimensional electron gas has the same simplicity and form as for the three-dimensional electron gas [J. Friedel, J. Nuovo. Cim. 7, 287 (1958), 10.1007/BF02751483] and can also be expressed in terms of scattering phase shifts.

  11. Biodegradation of nitroglycerin from propellant residues on military training ranges.

    PubMed

    Bordeleau, Geneviève; Martel, Richard; Drouin, Mathieu; Ampleman, Guy; Thiboutot, Sonia

    2014-03-01

    Nitroglycerin (NG) is often present in soils and sometimes in pore water at antitank firing positions due to incomplete combustion of propellants. Various degradation processes can contribute to the natural attenuation of NG in soils and pore water, thus reducing the risks of groundwater contamination. However, until now these processes have been sparsely documented. This study aimed at evaluating the ability of microorganisms from a legacy firing position to degrade dissolved NG, as well as NG trapped within propellant particles. Results from the shake-flask experiments showed that the isolated culture is capable of degrading dissolved NG but not the nitrocellulose matrix of propellant particles, so that the deeply embedded NG molecules cannot be degraded. Furthermore, the results from column experiments showed that in a nutrient-poor sand, degradation of dissolved NG may not be sufficiently rapid to prevent groundwater contamination. Therefore, the results from this study indicate that, under favorable soil conditions, biodegradation can be an important natural attenuation process for NG dissolving out of fresh propellant residues. In contrast, biodegradation does not contribute to the long-term attenuation of NG within old, weathered propellant residues. Although NG in these old residues no longer poses a threat to groundwater quality, if soil clean-up of a legacy site is required, active remediation approaches should be sought. PMID:25602645

  12. Early detection of postoperative residual tumor using image subtraction

    NASA Astrophysics Data System (ADS)

    Narayan, Suresh B.; Dhawan, Atam P.; Taha, Jamal M.; Gaskill-Shipley, Mary; Lamba, Michael; Sarwal, Alok; Chitre, Yateen S.

    1995-05-01

    The detection after surgery of residual tumor from magnetic resonance (MR) images is difficult due to the low contrast level of the images. Gadolinium-enhanced MR imaging has been found valuable in detecting residual enhancing tumor when performed within 72 hours after surgery. The patient is scanned by the MR scanner with and without infusion of gadolinium, a contrast agent. Usually, the estimation of post-operative tumor volume is done by visual comparison of the T1 MR images obtained with and without gadolinium infusion. The T1 MR images, in most cases, without contrast demonstrates areas of hyper intensities (high brightness levels), consistent with hemorrhage. These hyper intense areas often make it difficult to detect residual tumor in post contrast images. This is due to the presence of both acute hemorrhage and gadolinium enhancement which have high brightness levels in T1 MR images. Even in MR images taken within 72 hours after surgery, detection of tumor enhancement in areas of increased T1 signal produced by blood products or by postoperative changes can be difficult when performed by the naked eye. Due to these problems, the quantification of residual tumor becomes a subjective issue among neuro-radiologists. Thus to reduce errors produced by the human factor, an automated procedure to detect residual tumor is required. We have developed a technique to differentiate tumor enhancement from postoperative changes and blood products on MR imaging. The technique involves fusion of pre- and post-gadolinium MR images performed in the immediate postoperative period. Computerized slice based substraction is then done on the corresponding fused images of the two sets. The subtraction process results in a composite slice, which is examined for differences between pre- and post-gadolinium studies. The presented technique was tested on 14 cases in which MR images were obtained from brain tumor patients within 72 hours after surgery. The subtraction technique easily

  13. Ultrasonics used to measure residual stress

    NASA Technical Reports Server (NTRS)

    1967-01-01

    Ultrasonic method is used to measure residual stress in metal structures. By using this method, various forms of wave propagation in metals are possible, and more thorough analysis of complex geometric structures may be had.

  14. Recovery of transuranics from process residues

    SciTech Connect

    Gray, J.H.; Gray, L.W.

    1987-01-01

    Process residues are generated at both the Rocky Flats Plant (RFP) and the Savannah River Plant (SRP) during aqueous chemical and pyrochemical operations. Frequently, process operations will result in either impure products or produce residues sufficiently contaminated with transuranics to be nondiscardable as waste. Purification and recovery flowsheets for process residues have been developed to generate solutions compatible with subsequent Purex operations and either solid or liquid waste suitable for disposal. The ''scrub alloy'' and the ''anode heel alloy'' are examples of materials generated at RFP which have been processed at SRP using the developed recovery flowsheets. Examples of process residues being generated at SRP for which flowsheets are under development include LECO crucibles and alpha-contaminated hydraulic oil.

  15. Ceramic colorant from untreated iron ore residue.

    PubMed

    Pereira, Oscar Costa; Bernardin, Adriano Michael

    2012-09-30

    This work deals with the development of a ceramic colorant for glazes from an untreated iron ore residue. 6 mass% of the residue was added in suspensions (1.80 g/cm(3) density and 30s viscosity) of white, transparent and matte glazes, which were applied as thin layers (0.5mm) on engobeb and not fired ceramic tiles. The tiles were fired in laboratory roller kiln in a cycle of 35 min and maximum temperatures between 1050 and 1180°C. The residue and glazes were characterized by chemical (XRF) and thermal (DTA and optical dilatometry) analyses, and the glazed tiles by colorimetric and XRD analyses. The results showed that the colorant embedded in the transparent glaze results in a reddish glaze (like pine nut) suitable for the ceramic roof tile industry. For the matte and white glazes, the residue has changed the color of the tiles with temperature. PMID:22795839

  16. SAR impulse response with residual chirps.

    SciTech Connect

    Doerry, Armin Walter

    2009-06-01

    A Linear Frequency-Modulated (LFM) chirp is a function with unit amplitude and quadratic phase characteristic. In a focused Synthetic Aperture Radar (SAR) image, a residual chirp is undesired for targets of interest, as it coarsens the manifested resolution. However, for undesired spurious signals, a residual chirp is often advantageous because it spreads the energy and thereby diminishes its peak value. In either case, a good understanding of the effects of a residual LFM chirp on a SAR Impulse Response (IPR) is required to facilitate system analysis and design. This report presents an analysis of the effects of a residual chirp on the IPR. As reference, there is a rich body of publications on various aspects of LFM chirps. A quick search reveals a plethora of articles, going back to the early 1950s. We mention here purely as trivia one of the earlier analysis papers on this waveform by Klauder, et al.

  17. Differential Spectroscopic Imaging of Particulate Explosives Residue

    SciTech Connect

    Bernacki, Bruce E.; Ho, Nicolas

    2008-04-01

    We present experimental results showing transmission and reflection imaging of approximately 100 microgram quantities of particulate explosives residue using a commercial uncooled microbolometer infrared camera and CO2 laser differential wavelength illumination.

  18. Reduce HIV Risk

    MedlinePlus

    ... incidence could be reduced if people changed their sexual behaviors. Our research has demonstrated remarkable success in reducing HIV risk-associated sexual behaviors among African American adolescents and adults." Spring 2008 ...

  19. Modelling of Tool Wear and Residual Stress during Machining of AISI H13 Tool Steel

    NASA Astrophysics Data System (ADS)

    Outeiro, José C.; Umbrello, Domenico; Pina, José C.; Rizzuti, Stefania

    2007-05-01

    Residual stresses can enhance or impair the ability of a component to withstand loading conditions in service (fatigue, creep, stress corrosion cracking, etc.), depending on their nature: compressive or tensile, respectively. This poses enormous problems in structural assembly as this affects the structural integrity of the whole part. In addition, tool wear issues are of critical importance in manufacturing since these affect component quality, tool life and machining cost. Therefore, prediction and control of both tool wear and the residual stresses in machining are absolutely necessary. In this work, a two-dimensional Finite Element model using an implicit Lagrangian formulation with an automatic remeshing was applied to simulate the orthogonal cutting process of AISI H13 tool steel. To validate such model the predicted and experimentally measured chip geometry, cutting forces, temperatures, tool wear and residual stresses on the machined affected layers were compared. The proposed FE model allowed us to investigate the influence of tool geometry, cutting regime parameters and tool wear on residual stress distribution in the machined surface and subsurface of AISI H13 tool steel. The obtained results permit to conclude that in order to reduce the magnitude of surface residual stresses, the cutting speed should be increased, the uncut chip thickness (or feed) should be reduced and machining with honed tools having large cutting edge radii produce better results than chamfered tools. Moreover, increasing tool wear increases the magnitude of surface residual stresses.

  20. Dissipation dynamic, residue distribution and processing factor of hexythiazox in strawberry fruits under open field condition.

    PubMed

    Saber, Ayman N; Malhat, Farag M; Badawy, Hany M A; Barakat, Dalia A

    2016-04-01

    Two independent field trials were performed to investigate the dissipation and residue levels of hexythiazox in strawberry. The study presents a method validation for extraction and quantitative analysis of hexythiazox residues in strawberry using HPLC-DAD. The results shown that the mean recoveries ranged from 85% to 93%, furthermore the intra- and inter-day relative standard deviations were less than 10%. The results suggest that the hexythiazox dissipation curves followed the first-order kinetic and its half-life ranged from 3.43 to 3.81 days. The final residues in strawberry were below the Codex maximum residue limit (MRL) (6 mg/kg) after three days of the application. The effects of household processing and storage on the levels of hexythiazox residues were quantified, and it's useful for reducing the dietary exposure. The processing factor after each stage were generally less than 1, indicating that the whole process can reduce the residues of hexythiazox in strawberry. The results could provide guidance to safe and reasonable use of hexythiazox in agriculture. PMID:26593595

  1. Sago pith residue as an alternative cheap substrate for fermentable sugars production.

    PubMed

    Linggang, S; Phang, L Y; Wasoh, M H; Abd-Aziz, S

    2012-05-01

    Sago pith residue is one of the most abundant lignocellulosic biomass which can serve as an alternative cheap substrate for fermentable sugars production. This residue is the fibrous waste left behind after the starch extraction process and contains significant amounts of starch (58%), cellulose (23%), hemicellulose (9.2%) and lignin (3.9%). The conversion of sago pith residue into fermentable sugars is commonly performed using cellulolytic enzymes or known as cellulases. In this study, crude cellulases were produced by two local isolates, Trichoderma asperellum UPM1 and Aspergillus fumigatus, UPM2 using sago pith residue as substrate. A. fumigatus UPM2 gave the highest FPase, CMCase and β-glucosidase activities of 0.39, 23.99 and 0.78 U/ml, respectively, on day 5. The highest activity of FPase, CMCase and β-glucosidase by T. asperellum UPM1 was 0.27, 12.03 and 0.42 U/ml, respectively, on day 7. The crude enzyme obtained from A. fumigatus UPM2 using β-glucosidase as the rate-limiting enzyme (3.9, 11.7 and 23.4 IU) was used for the saccharification process to convert 5% (w/v) sago pith residue into reducing sugars. Hydrolysis of sago pith residue using crude enzyme containing β-glucosidase with 23.4 IU, produced by A. fumigatus UPM2 gave higher reducing sugars production of 20.77 g/l with overall hydrolysis percentage of 73%. PMID:22528646

  2. Modelling of Tool Wear and Residual Stress during Machining of AISI H13 Tool Steel

    SciTech Connect

    Outeiro, Jose C.; Pina, Jose C.; Umbrello, Domenico; Rizzuti, Stefania

    2007-05-17

    Residual stresses can enhance or impair the ability of a component to withstand loading conditions in service (fatigue, creep, stress corrosion cracking, etc.), depending on their nature: compressive or tensile, respectively. This poses enormous problems in structural assembly as this affects the structural integrity of the whole part. In addition, tool wear issues are of critical importance in manufacturing since these affect component quality, tool life and machining cost. Therefore, prediction and control of both tool wear and the residual stresses in machining are absolutely necessary. In this work, a two-dimensional Finite Element model using an implicit Lagrangian formulation with an automatic remeshing was applied to simulate the orthogonal cutting process of AISI H13 tool steel. To validate such model the predicted and experimentally measured chip geometry, cutting forces, temperatures, tool wear and residual stresses on the machined affected layers were compared. The proposed FE model allowed us to investigate the influence of tool geometry, cutting regime parameters and tool wear on residual stress distribution in the machined surface and subsurface of AISI H13 tool steel. The obtained results permit to conclude that in order to reduce the magnitude of surface residual stresses, the cutting speed should be increased, the uncut chip thickness (or feed) should be reduced and machining with honed tools having large cutting edge radii produce better results than chamfered tools. Moreover, increasing tool wear increases the magnitude of surface residual stresses.

  3. Proposal for management and alkalinity transformation of bauxite residue in China.

    PubMed

    Xue, Shengguo; Kong, Xiangfeng; Zhu, Feng; Hartley, William; Li, Xiaofei; Li, Yiwei

    2016-07-01

    Bauxite residue is a hazardous solid waste produced during the production of alumina. Its high alkalinity is a potential threat to the environment which may disrupt the surrounding ecological balance of its disposal areas. China is one of the major global producers of alumina and bauxite residue, but differences in alkalinity and associated chemistry exist between residues from China and those from other countries. A detailed understanding of the chemistry of bauxite residue remains the key to improving its management, both in terms of minimizing environmental impacts and reducing its alkaline properties. The nature of bauxite residue and the chemistry required for its transformation are still poorly understood. This review focuses on various transformation processes generated from the Bayer process, sintering process, and combined Bayer-sintering process in China. Problems associated with transformation mechanisms, technical methods, and relative merits of these technologies are reviewed, while current knowledge gaps and research priorities are recommended. Future research should focus on transformation chemistry and its associated mechanisms and for the development of a clear and economic process to reduce alkalinity and soda in bauxite residue. PMID:27023808

  4. Effect of home processing on the distribution and reduction of pesticide residues in apples.

    PubMed

    Kong, Z; Shan, W; Dong, F; Liu, X; Xu, J; Li, M; Zheng, Y

    2012-08-01

    The effect of home processing (washing, peeling, coring and juicing) on residue levels of chlorpyrifos, β-cypermethrin, tebuconazole, acetamiprid and carbendazim in apple segments was investigated. The pesticide residues were determined by UPLC-MS/MS and GC with a flame photometric (FPD) and electron capture detection (ECD). The results indicated that the pesticide residue levels in the apple peel and core were higher compared with in the apple flesh. After peeled and cored apple was processed into apple juice and pomace, chlorpyrifos, β-cypermethrin and tebuconazole were concentrated in the apple pomace. However, residues of acetamiprid and carbendazim were exceptions. The apple pomace was free of acetamiprid, which was mainly present in the apple juice. After washing the mean loss of chlorpyrifos, β-cypermethrin, tebuconazole, acetamiprid and carbendazim from apples under recommended dosage and twofold higher dosage were 17-21%, 6.7-7.1%, 13-32%, 42-67% and 47-50%, respectively. The pesticide residues were significantly reduced in the edible part of the apple except for β-cypermethrin during peeling and coring process. The removal effect of apple juicing was found to be the most pronounced on β-cypermethrin residue, which was reduced in the range of 81-84%, and the reductions of chlorpyrifos, tebuconazole, acetamiprid and carbendazim upon apple juicing were in the range of 15-36%. PMID:22738391

  5. In-situ measurement of residual stresses during the nitriding process

    SciTech Connect

    Hoffman, F.T.; Kreft, U.; Hirsch, T.; Mayr, P.

    1995-12-31

    Residual stresses have a strong influence on the properties of nitrided parts. Therefore knowledge of their origin and magnitude is of great interest and a prerequisite if changes in the stresses are intended. From the relevant theories of residual stresses in gas nitrided materials it can be concluded that stresses which are generated during nitriding can be reduced by plastic deformation during the nitriding process and increased during cooling from nitriding temperature to room temperature. The increase of residual stresses in the compound layer should be a result of the volume misfit generated by different thermal expansion coefficients of compound layer and diffusion zone. These theories mentioned have not been confirmed by experimental work up to now. Therefore, one aim of the investigations was to clarify the origin of residual stresses as well as the different influences on the formation of residual stresses. Previously, residual stresses of nitrided parts could only be measured after nitriding. In the present work it will be shown, for the first time, that residual stresses can successfully be determined in situ during the gas nitriding process by a special nitriding device installed in an X-ray diffractometer. By this way the influences of the parameters nitriding potential, nitriding temperature, cooling process, and carbon content of the investigated material can be shown.

  6. Effect of Residual Stresses on the Hardness of Bulk Metallic Glasses

    SciTech Connect

    Wang, L.; Bei, Hongbin; Gao, Y. F.; Lu, Zhao Ping; Nieh, T. G.

    2011-01-01

    Nanoindentation experiments were conducted on Zr-based metallic glass samples, which were elastically and plastically bent in order to investigate the effect of residual stresses on hardness. It was found that tensile residual stress reduced the hardness significantly, while compressive residual stress produced only a small effect on the hardness. These observations are consistent with three-dimensional continuum-plasticity-based finite-element simulations. The hardness was also found to vary more significantly with residual stresses, in particular in tension, than that caused by shear-banding-induced softening, suggesting hardness measurement is a practical method for the evaluation of tensile residual stresses in a metallic glass. Hardness variation in the bent sample was correlated with the residual-stress induced volume dilatation through a free-volume-based model. In this paper, we also present a detailed stress analysis based on yield asymmetry under tension and compression to describe the distribution of residual stresses in bent metallic glass specimens. The calculations agree well with the hardness variations measured experimentally.

  7. Reductive transformation of bound trinitrophenyl residues and free TNT during a bioremediation process analyzed by immunoassay

    SciTech Connect

    Achtnich, C.; Pfortner, P.; Weller, M.G.; Niessner, R.; Lenke, H.; Knackmuss, H.J.

    1999-10-01

    To follow the fate of bound metabolites of TNT in soil, a synthetic trinitrophenyl residue covalently linked to humic acids was used as model compound. A selective monoclonal antibody was able to detect chemical changes of the nitro groups of the bound residues. The general possibility of reductive transformations of nitro groups of bound molecules and the reduction rates should be determined. In comparison to the reduction of free TNT and its metabolites, the reductive transformation of the bound trinitrophenyl residue was delayed, and the transformation rate was considerably slower. Trinitrophenyl residues also could be detected by the immunoassay in humic acids extracted from TNT contaminated soil. The reductive transformation of these trinitrophenyl residues started after the reduction of free TNT. At the end of the treatment, small amounts of these residues were still detectable indicating that some of these structures were not completely reduced during the process. From present results one can conclude that the further reduction of nitro groups of bound metabolites requires a prolonged anaerobic treatment. Not only the monitoring of free nitroaromatic compounds is recommended during the bioremediation process but also the measurement of bound residues to determine the optimal conditions and duration of the treatment.

  8. Detecting Residues On Grit-Blasted Surfaces

    NASA Technical Reports Server (NTRS)

    Novak, H. L.; Zook, L. M.

    1989-01-01

    Addition of fluorescent or iridescent material to plastic grit particles proposed for detection of grit residues after grit-blast cleaning. Residual films visible by observing grit-blasted surfaces under infrared or ultraviolet light. Plastic grit contains fluorescent or iridescent additive in core and coating. Wherever grit material becomes embedded, additive makes it visible under infrared or ultraviolet light. Applicable to other grit materials, for example fluorescent or iridescent materials added to particles of glass, silicon carbide, aluminum oxide, or zirconium silicate.

  9. Bayesian nonparametric regression with varying residual density.

    PubMed

    Pati, Debdeep; Dunson, David B

    2014-02-01

    We consider the problem of robust Bayesian inference on the mean regression function allowing the residual density to change flexibly with predictors. The proposed class of models is based on a Gaussian process prior for the mean regression function and mixtures of Gaussians for the collection of residual densities indexed by predictors. Initially considering the homoscedastic case, we propose priors for the residual density based on probit stick-breaking (PSB) scale mixtures and symmetrized PSB (sPSB) location-scale mixtures. Both priors restrict the residual density to be symmetric about zero, with the sPSB prior more flexible in allowing multimodal densities. We provide sufficient conditions to ensure strong posterior consistency in estimating the regression function under the sPSB prior, generalizing existing theory focused on parametric residual distributions. The PSB and sPSB priors are generalized to allow residual densities to change nonparametrically with predictors through incorporating Gaussian processes in the stick-breaking components. This leads to a robust Bayesian regression procedure that automatically down-weights outliers and influential observations in a locally-adaptive manner. Posterior computation relies on an efficient data augmentation exact block Gibbs sampler. The methods are illustrated using simulated and real data applications. PMID:24465053

  10. Fluorescence imaging to quantify crop residue cover

    NASA Technical Reports Server (NTRS)

    Daughtry, C. S. T.; Mcmurtrey, J. E., III; Chappelle, E. W.

    1994-01-01

    Crop residues, the portion of the crop left in the field after harvest, can be an important management factor in controlling soil erosion. Methods to quantify residue cover are needed that are rapid, accurate, and objective. Scenes with known amounts of crop residue were illuminated with long wave ultraviolet (UV) radiation and fluorescence images were recorded with an intensified video camera fitted with a 453 to 488 nm band pass filter. A light colored soil and a dark colored soil were used as background for the weathered soybean stems. Residue cover was determined by counting the proportion of the pixels in the image with fluorescence values greater than a threshold. Soil pixels had the lowest gray levels in the images. The values of the soybean residue pixels spanned nearly the full range of the 8-bit video data. Classification accuracies typically were within 3(absolute units) of measured cover values. Video imaging can provide an intuitive understanding of the fraction of the soil covered by residue.

  11. Resist residue removal using UV ozone treatment

    NASA Astrophysics Data System (ADS)

    Chen, Shu-Fang; Chang, Ching-Yu; Ku, Yao-Ching

    2010-04-01

    In a conventional lithography process, the resist pattern is removed by dry strip or wet chemical etch. The wet chemical etch includes sulfuric peroxide etch and solvent etch. The wet chemical etch process is always combined with the dry strip process to meet the residue process spec. However, in some applications, only the wet-etch process can be used to avoid substrate damage during the plasma step. However, organic residue can be found from particle surface scan and TGA/DSC after normal solvent strip. In this paper, we investigate polymer residue stripping using only solvent as well as solvent in combination with UV treatment. For solvents only, some solvents different from the conventional PGMEA/PGME mixture in polarity, also exhibited stripping ability but the efficiency is not as good as PGME/PGMEA mixture. When supplemented with UV treatment, the organic residue can be further decomposed and removed completely. The UV we used contains 185nm and 254nm wavelengths. Ozone is generated during UV exposure and acts as oxidant. The organic residue is thus decomposed and removed. It has been proven as an effective method to cleave the C-C bond without damaging the wafer substrate. The organic residue on the wafer surface can be easily stripped away under UV-ozone exposure. Its defect performance is also discussed in this paper.

  12. RESIDUAL ENERGY SPECTRUM OF SOLAR WIND TURBULENCE

    SciTech Connect

    Chen, C. H. K.; Bale, S. D.; Salem, C. S.; Maruca, B. A.

    2013-06-20

    It has long been known that the energy in velocity and magnetic field fluctuations in the solar wind is not in equipartition. In this paper, we present an analysis of 5 yr of Wind data at 1 AU to investigate the reason for this. The residual energy (difference between energy in velocity and magnetic field fluctuations) was calculated using both the standard magnetohydrodynamic (MHD) normalization for the magnetic field and a kinetic version, which includes temperature anisotropies and drifts between particle species. It was found that with the kinetic normalization, the fluctuations are closer to equipartition, with a mean normalized residual energy of {sigma}{sub r} = -0.19 and mean Alfven ratio of r{sub A} = 0.71. The spectrum of residual energy, in the kinetic normalization, was found to be steeper than both the velocity and magnetic field spectra, consistent with some recent MHD turbulence predictions and numerical simulations, having a spectral index close to -1.9. The local properties of residual energy and cross helicity were also investigated, showing that globally balanced intervals with small residual energy contain local patches of larger imbalance and larger residual energy at all scales, as expected for nonlinear turbulent interactions.

  13. Pyrethroid insecticide residues on vegetable crops.

    PubMed

    Ripley, B D; Ritcey, G M; Harris, C R; Denommé, M A; Brown, P D

    2001-08-01

    Pyrethroid insecticides were applied on various vegetable crops as foliar treatments to determine dissipation rates. On Chinese broccoli (Guy Lon), Chinese mustard (Pak Choi) and Chinese cabbage (Kasumi, napa), fenvalerate was persistent with residues of 0.10, 0.14 and 0.11 mg kg-1, respectively, by day 21. Cypermethrin residues on head lettuce were below 0.1 mg kg-1 by day 10 but on the leafier romaine and endive varieties it was more persistent and required 14-19 days to dissipate below this concentration. After three applications, residues of cypermethrin in harvested carrots and of permethrin in eggplant were not detected on the day of application. On asparagus, deltamethrin and cypermethrin residues declined to less than 0.1 mg kg-1 by days 1 and 2, respectively; permethrin was more persistent, requiring more than 2 days to decline to less than 0.1 mg kg-1. Deltamethrin on dry (cooking) and Spanish onions was not detected on the day of application. On tomatoes, the concentration of permethrin was 0.093 mg kg-1 on the day of application and declined to about 0.05 mg kg-1 after 2-4 days. In general, permethrin, cypermethrin and deltamethrin residues declined to acceptable concentrations within an acceptable pre-harvest interval. Fenvalerate may be too persistent on these speciality crops unless a maximum residue limit > 0.1 mg kg-1 is permitted. PMID:11517721

  14. Method for residual household waste composition studies.

    PubMed

    Sahimaa, Olli; Hupponen, Mari; Horttanainen, Mika; Sorvari, Jaana

    2015-12-01

    The rising awareness of decreasing natural resources has brought forward the idea of a circular economy and resource efficiency in Europe. As a part of this movement, European countries have identified the need to monitor residual waste flows in order to make recycling more efficient. In Finland, studies on the composition of residual household waste have mostly been conducted using different methods, which makes the comparison of the results difficult. The aim of this study was to develop a reliable method for residual household waste composition studies. First, a literature review on European study methods was performed. Also, 19 Finnish waste composition studies were compared in order to identify the shortcomings of the current Finnish residual household waste composition data. Moreover, the information needs of different waste management authorities concerning residual household waste were studied through a survey and personal interviews. Stratification, sampling, the classification of fractions and statistical analysis were identified as the key factors in a residual household waste composition study. The area studied should be divided into non-overlapping strata in order to decrease the heterogeneity of waste and enable comparisons between different waste producers. A minimum of six subsamples, each 100 kg, from each stratum should be sorted. Confidence intervals for each waste category should be determined in order to evaluate the applicability of the results. A new three-level classification system was created based on Finnish stakeholders' information needs and compared to four other European waste composition study classifications. PMID:26337965

  15. Microbiological characterization of food residues for animal feeding.

    PubMed

    Sancho, Pilar; Pinacho, Ana; Ramos, Pedro; Tejedor, Carmen

    2004-01-01

    A description is offered of microbiological characterization of the biodegradable fractions present in food wastes so that those fractions can be transformed in such a way that they will fulfil the specifications involved in their use as raw materials in other production areas. In this way the wastes can be converted into sub-products, hence minimizing the amount of them eventually sent to rubbish dumps. Of all the types of residues analyzed, only those obtained by separate collection from fishmongers' and greengrocers' sections of large supermarkets and small shops were valid for the objectives of the project and were subjected to a heat treatment to test whether or not this treatment was capable of reducing their microbiological content to the point of converting them into acceptable raw materials for animal feed. Residues from butchers' sections of supermarkets and small shops, and residues from restaurants were not included in the final study because of the prohibition by the European legislation in force of using any kind of meat containing wastes for feeding farm animals. In the present work we made a one-year analysis of representative samples of such wastes. We observed that after thermal treatment at a temperature of at least 65 degrees C for 20 min the nutritional and microbiological parameters remained suitable for their possible use as animal feed and that their harmlessness was ensured, with no loss of nutritional characteristics. Regarding the microbiological study of the meals which have been obtained from residues for the production of the feed and the feed itself, and in accordance with the data for nutritional composition, we consider valid and sanitarily adequate their use as animal feed with the concomitant consequent minimization of waste, which has become a priority in view of the recent legislation enacted by the European Union. PMID:15504669

  16. Suggested methods for determining residual tritium in process beds

    SciTech Connect

    Hoelder, J.S.

    1992-10-29

    This memorandum has been written as a response to an H-Area EH Issue No. 3 milestone (SRTC FY93 Controlled Milestone 15C70) which requires WSRC to {open_quotes}develop methodology for determining residual tritium in process equipment.{close_quotes} An estimate of the tritium residing in process equipment sent for disposal must be reported on a Waste Stream Characterization Form. Currently, these estimates are crude and their technical bases are not well documented. The process equipment addressed in this report may be divided into two categories, routine and non-routine, based on their generation frequency. Magnesium Beds, Uranium Beds, and Gold Traps are regularly sent for disposal depending on the process load; Zeolite Beds and Catalyst Beds are rarely removed from the Tritium Facilities, as they may be regenerated. In general, there are two main sources of residual tritium that which resides in hydroxyl groups on internal surfaces and deposits, and that which has permeated the stainless steel walls and components. The tritiated hydroxyl groups may be exchangeable with gas phase deuterium, and minimized by oxidation at elevated temperatures. The tritium which has diffused into stainless steel is difficult to remove and amounts to a minor portion of the total tritium heel; this value may be calculated by a proven computer program and is on the order of 1--5 Ci per bed. Zeolite Beds are a unique case, as the packing material contains a substantial portion of crystalline hydrate (2% by weight), even after bake out at 500{degrees}C The solid state hydrate will assimilate tritium from adsorbed waters, and calculations show a typical Z-bed may contain 50,000 Ci of residual tritium. It is proposed that a calorimeter be designed and constructed to measure the tritium in Z-beds directly, and that steps be taken to reduce the residual tritium by extraction with deuterated water.

  17. 40 CFR 180.339 - MCPA; tolerances for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...; tolerances for residues. (a) General. (1) Tolerances are established for residues of the herbicide MCPA ((4... for residues of the herbicide MCPA ((4-chloro-2-methylphenoxy)acetic acid) resulting from the...

  18. 40 CFR 180.339 - MCPA; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...; tolerances for residues. (a) General. (1) Tolerances are established for residues of the herbicide MCPA ((4... for residues of the herbicide MCPA ((4-chloro-2-methylphenoxy)acetic acid) resulting from the...

  19. 40 CFR 180.432 - Lactofen; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Lactofen; tolerances for residues. (a) Tolerances are established for residues of the herbicide lactofen, 1... residues of the herbicide, lactofen, 1-(carboethoxy)ethyl 5- -2- nitrobenzoate, in or on the following...

  20. 40 CFR 180.339 - MCPA; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...; tolerances for residues. (a) General. (1) Tolerances are established for residues of the herbicide MCPA ((4... for residues of the herbicide MCPA ((4-chloro-2-methylphenoxy)acetic acid) resulting from the...

  1. 40 CFR 180.339 - MCPA; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...; tolerances for residues. (a) General. (1) Tolerances are established for residues of the herbicide MCPA ((4... for residues of the herbicide MCPA ((4-chloro-2-methylphenoxy)acetic acid) resulting from the...

  2. 40 CFR 180.339 - MCPA; tolerances for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...; tolerances for residues. (a) General. (1) Tolerances are established for residues of the herbicide MCPA ((4... for residues of the herbicide MCPA ((4-chloro-2-methylphenoxy)acetic acid) resulting from the...

  3. Addition of an organic amendment and/or residue mud to bauxite residue sand in order to improve its properties as a growth medium.

    PubMed

    Jones, B E H; Haynes, R J; Phillips, I R

    2012-03-01

    The effects of addition of carbonated residue mud (RMC) or seawater neutralized residue mud (RMS), at two rates, in the presence or absence of added green waste compost, on the chemical, physical and microbial properties of gypsum-treated bauxite residue sand were studied in a laboratory incubation study. The growth of two species commonly used in revegetation of residue sand (Lolium rigidum and Acacia saligna) in the treatments was then studied in a 18-week greenhouse study. Addition of green waste-based compost increased ammonium acetate-extractable (exchangeable) Mg, K and Na. Addition of residue mud at 5 and 10% w/w reduced exchangeable Ca but increased that of Mg and Na (and K for RMS). Concentrations of K, Na, Mg and level of EC in saturation paste extracts were increased by residue mud additions. Concentrations of cations in water extracts were considerably higher than those in saturation paste extracts but trends with treatment were broadly similar. Addition of both compost and residue mud caused a significant decrease in macroporosity with a concomitant increase in mesoporosity and microporosity, available water holding capacity and the quantity of water held at field capacity. Increasing rates of added residue mud reduced the percentage of sample present as discrete sand particles and increased that in aggregated form (particularly in the 1-2 and >10mm diameter ranges). Organic C content, C/N ratio, soluble organic C, microbial biomass C and basal respiration were increased by compost additions. Where compost was added, residue mud additions caused a substantial increase in microbial biomass and basal respiration. L. rigidum grew satisfactorily in all treatments although yields tended to be reduced by additions of mud (especially RMC) particularly in the absence of added compost. Growth of A. saligna was poor in sand alone and mud-amended sand and was greatly promoted by additions of compost. However, in the presence of compost, addition of carbonated

  4. Rye residues contribute weed suppression in no-tillage cropping systems.

    PubMed

    Barnes, J P; Putnam, A R

    1983-08-01

    The use of allelopathic cover crops in reduced tillage cropping systems may provide an ecologically sound and environmentally safe management strategy for weed control. Growers often plant winter rye (Secale cereale L.) for increased soil organic matter and soil protection. Spring-planted living rye reduced weed biomass by 93% over plots without rye. Residues of fall-planted/spring-killed rye reduced total weed biomass over bare-ground controls. Rye residues also reduced total weed biomass by 63% when poplar excelsior was used as a control for the mulch effect, suggesting that allelopathy, in addition to the physical effects of the mulch, did contribute to weed control in these systems. In greenhouse studies, rye root leachates reduced tomato dry weight by 25-30%, which is additional evidence that rye is allelopathic to other plant species. PMID:24407799

  5. Simplified micromechanical equations for thermal residual stress analysis of coated fiber composites

    NASA Technical Reports Server (NTRS)

    Naik, Rajiv A.

    1992-01-01

    The fabrication of metal matrix composites poses unique problems to the materials engineer. The large thermal expansion coefficient mismatch between the fiber and matrix leads to high tensile residual stresses at the fiber/matrix interface which could lead to premature matrix cracking during cooldown. Fiber coating could be used to reduce thermal residual stresses. A simple closed-form analysis, based on a three-phase composite cylinder model, was developed to calculate thermal residual stresses in a fiber/interface/matrix system. Guidelines, in the form of simple equations, for the selection of appropriate material properties of the fiber coating, were also derived to minimize thermal residual stresses in the matrix during fabrication.

  6. Laser Treatment of HVOF Coating: Modeling and Measurement of Residual Stress in Coating

    NASA Astrophysics Data System (ADS)

    Arif, A. F. M.; Yilbas, B. S.

    2008-10-01

    High-velocity oxy-fuel (HVOF) coating of diamalloy 1005 (similar to Inconel 625 alloy) onto the Ti-6Al-4V alloy is considered and laser-controlled melting of the coating is examined. The residual stress developed after the laser treatment process is modeled using the finite element method (FEM). The experiment is conducted to melt the coating using a laser beam. The residual stress measurement in the coating after the laser treatment process is realized using the XRD technique. The morphological and metallurgical changes in the coating are examined using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). It is found that the residual stress reduces at the coating-base material interface and the residual stress predicted agrees with the XRD measurements. A compact and crack-free coating is resulted after the laser treatment process.

  7. Insecticide residues in head lettuce, cabbage, Chinese cabbage, and broccoli grown in fields.

    PubMed

    Chen, Miao-Fan; Chen, Jung-Fang; Syu, Jing-Jing; Pei, Chi; Chien, Hsiu-Pao

    2014-04-23

    The residues of four insecticides belonging to different families were studied on head lettuce (Lactuca sativa L. var. capitata L.), cabbage (Brassica oleracea Linn. var. capitata DC.), Chinese cabbage (Brassica pekinensis Skeels), and broccoli (Brassica oleracea var. italica) after pesticide application. To reduce application variability, a tank mix of acetamiprid 20% SP, chlorpyrifos 22.5% EC, deltamethrin 2.4% SC, and methomyl 40% SP was applied at recommended and double doses. Initial deposits of all pesticides on head lettuce were higher than those of the other three crops. The residues of chlorpyrifos and deltamethrin were higher than the maximum residue limits (MRLs) at recommended preharvest intervals (PHIs) on head lettuce and Chinese broccoli treated with higher doses. The residues of methomyl on head lettuce also showed the same phenomenon. PMID:24684565

  8. Chemical and Mechanical Analysis of HDIS Residues using Auger Electron Spectroscopy and Nanoindentation

    SciTech Connect

    Kadavanich, Andreas Virin; Shim, Sang Hoon; Meyer III, Harry M; Savas, Stephen E.; Lara-Curzio, Edgar

    2009-01-01

    Photoresist stripping after ion implantation at high dosages (>1E15 atoms/cm2) is the most challenging dry strip process for advanced logic devices. Such high-dose implant stripping (HDIS) frequently leaves residues on the wafers after dry strip, unless fluorine chemistries are employed in the stripping plasma. Silicon loss requirements at sub-45nm nodes generally preclude such aggressive stripping chemistries. Instead, a wet clean is used to remove residues. However, the nature of the residues is not well understood, and are believed to usually contain some of the cross-linked, carbonized organic polymer formed in the implant [1]. In this paper we present chemical and mechanical data on HDIS residues produced from oxidizing and reducing chemistry strip processes

  9. 40 CFR 180.659 - Pyroxasulfone; tolerances for residues.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... residues of the herbicide pyroxasulfone, including its metabolites and degradates, in or on the commodities....015 (2) Tolerances are established for residues of the herbicide pyroxasulfone, including...

  10. 40 CFR 180.600 - Propoxycarbazone; tolerances for residues

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... combined residues of the herbicide propoxycarbazone methyl 2- amino]sulfonyl]benzoate and its metabolite....05 (2) Tolerances are established for residues of the herbicide propoxycarbazone methyl 2-...

  11. 40 CFR 180.600 - Propoxycarbazone; tolerances for residues.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... combined residues of the herbicide propoxycarbazone methyl 2- amino]sulfonyl]benzoate and its metabolite....05 (2) Tolerances are established for residues of the herbicide propoxycarbazone methyl 2-...

  12. 40 CFR 180.600 - Propoxycarbazone; tolerances for residues

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... combined residues of the herbicide propoxycarbazone methyl 2- amino]sulfonyl]benzoate and its metabolite....05 (2) Tolerances are established for residues of the herbicide propoxycarbazone methyl 2-...

  13. 40 CFR 180.600 - Propoxycarbazone; tolerances for residues

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... combined residues of the herbicide propoxycarbazone methyl 2- amino]sulfonyl]benzoate and its metabolite....05 (2) Tolerances are established for residues of the herbicide propoxycarbazone methyl 2-...

  14. 40 CFR 180.600 - Propoxycarbazone; tolerances for residues.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... combined residues of the herbicide propoxycarbazone methyl 2- amino]sulfonyl]benzoate and its metabolite....05 (2) Tolerances are established for residues of the herbicide propoxycarbazone methyl 2-...

  15. A survey of residual analysis and a new test of residual trend.

    PubMed

    McDowell, J J; Calvin, Olivia L; Klapes, Bryan

    2016-05-01

    A survey of residual analysis in behavior-analytic research reveals that existing methods are problematic in one way or another. A new test for residual trends is proposed that avoids the problematic features of the existing methods. It entails fitting cubic polynomials to sets of residuals and comparing their effect sizes to those that would be expected if the sets of residuals were random. To this end, sampling distributions of effect sizes for fits of a cubic polynomial to random data were obtained by generating sets of random standardized residuals of various sizes, n. A cubic polynomial was then fitted to each set of residuals and its effect size was calculated. This yielded a sampling distribution of effect sizes for each n. To test for a residual trend in experimental data, the median effect size of cubic-polynomial fits to sets of experimental residuals can be compared to the median of the corresponding sampling distribution of effect sizes for random residuals using a sign test. An example from the literature, which entailed comparing mathematical and computational models of continuous choice, is used to illustrate the utility of the test. PMID:27193244

  16. Vegetable fiber fermentation by human fecal bacteria: cell wall polysaccharide disappearance and short-chain fatty acid production during in vitro fermentation and water-holding capacity of unfermented residues.

    PubMed

    Bourquin, L D; Titgemeyer, E C; Fahey, G C

    1993-05-01

    Dietary fiber from eight vegetables (broccoli, carrot, cauliflower, celery, cucumber, lettuce, onion and radish) was analyzed for chemical composition and potential in vitro fermentation by human fecal bacteria. Total dietary fiber concentration of substrates ranged from 34.9 (broccoli) to 5.8 (cucumber) g/kg edible matter. Substrate fiber fractions were composed primarily of pectic substances and cellulose with smaller concentrations of hemicelluloses and lignin. Total dietary fiber residues isolated from substrates were fermented in vitro for 24 h with fecal bacteria obtained from each of three human volunteers. Substrate dry matter disappearance during fermentation was highest for carrot (63.7%) and lowest for cucumber (49.4%). Averaged across all substrates, disappearances of arabinose, galactose, glucose, mannose, xylose and uronic acids during fermentation were 96, 90, 54, 68, 51 and 97%, respectively. Short-chain fatty acid (SCFA) production during substrate fermentation averaged 10.5 mmol SCFA/g dry matter fermented. Averaged across all substrates, production of the major SCFA, acetate, propionate and butyrate, occurred in the molar ratio 76:14:10. Potential water-holding capacity of substrates was not influenced by fiber source and averaged 2.04 g H2O/g original substrate dry matter. Extent of substrate fermentation, SCFA production and substrate potential water-holding capacity were significantly different among inoculum donors, indicating that considerable inter-individual variation exists in the potential in vivo fermentation of vegetable fiber. PMID:8387579

  17. Influence of water treatment residuals on phosphorus solubility and leaching.

    PubMed

    Elliott, H A; O'Connor, G A; Lu, P; Brinton, S

    2002-01-01

    Laboratory and greenhouse studies compared the ability of water treatment residuals (WTRs) to alter P solubility and leaching in Immokalee sandy soil (sandy, siliceous, hyperthermic Arenic Alaquod) amended with biosolids and triple superphosphate (TSP). Aluminum sulfate (Al-WTR) and ferric sulfate (Fe-WTR) coagulation residuals, a lime softening residual (Ca-WTR) produced during hardness removal, and pure hematite were examined. In equilibration studies, the ability to reduce soluble P followed the order Al-WTR > Ca-WTR = Fe-WTR > hematite. Differences in the P-fixing capacity of the sesquioxide-dominated materials (Al-WTR, Fe-WTR, hematite) were attributed to their varying reactive Fe- and Al-hydrous oxide contents as measured by oxalate extraction. Leachate P was monitored from greenhouse columns where bahiagrass (Paspalum notatum Flugge) was grown on Immokalee soil amended with biosolids or TSP at an equivalent rate of 224 kg P ha(-1) and WTRs at 2.5% (56 Mg ha(-1)). In the absence of WTRs, 21% of TSP and 11% of Largo cake biosolids total phosphorus (PT) leached over 4 mo. With co-applied WTRs, losses from TSP columns were reduced to 3.5% (Fe-WTR), 2.5% (Ca-WTR), and <1% (Al-WTR) of applied P. For the Largo biosolids treatments all WTRs retarded downward P flux such that leachate P was not statistically different than for control (soil only) columns. The phosphorus saturation index (PSI = [Pox]/ [Al(ox) + Fe(ox)], where Pox, Al, and Fe(ox) are oxalate-extractable P, Al, and Fe, respectively) based on a simple oxalate extraction of the WTR and biosolids is potentially useful for determining WTR application rates for controlled reduction of P in drainage when biosolids are applied to low P-sorbing soils. PMID:12175057

  18. Load dissipation by corn residue on tilled soil in laboratory and field-wheeling conditions.

    PubMed

    Reichert, José M; Brandt, André A; Rodrigues, Miriam F; Reinert, Dalvan J; Braida, João A

    2016-06-01

    Crop residues may partially dissipate applied loads and reduce soil compaction. We evaluated the effect of corn residue on energy-applied dissipation during wheeling. The experiment consisted of a preliminary laboratory test and a confirmatory field test on a Paleaudalf soil. In the laboratory, an adapted Proctor test was performed with three energy levels, with and without corn residue. Field treatments consisted of three 5.1 Mg tractor wheeling intensities (0, 2, and 6), with and without 12 Mg ha(-1) corn residue on the soil surface. Corn residue on the soil surface reduced soil bulk density in the adapted Proctor test. By applying energy of 52.6 kN m m(-3) , soil dissipated 2.98% of applied energy, whereas with 175.4 kN m m(-3) a dissipation of 8.60% was obtained. This result confirms the hypothesis that surface mulch absorbs part of the compaction effort. Residue effects on soil compaction observed in the adapted Proctor test was not replicated under subsoiled soil field conditions, because of differences in applied pressure and soil conditions (structure, moisture and volume confinement). Nevertheless, this negative result does not mean that straw has no effect in the field. Such effects should be measured via stress transmission and compared to soil load-bearing capacity, rather than on bulk deformations. Wheeling by heavy tractor on subsoiled soil increased compaction, independently of surface residue. Two wheelings produced a significantly increase, but six wheelings did not further increase compaction. Reduced traffic intensity on recently tilled soil is necessary to minimize soil compaction, since traffic intensity show a greater effect than surface mulch on soil protection from excessive compaction. © 2015 Society of Chemical Industry. PMID:26304050

  19. Residual aqueous ozone determination by gas diffusion flow injection analysis

    SciTech Connect

    Straka, M.R.; Gordon, G.; Pacey, G.E.

    1985-08-01

    A method for the determination of residual aqueous ozone utilizing the technique of gas diffusion flow injection analysis and the redox reagents potassium indigo trisulfonate and bis(terpyridine)iron(II) is described. The system uses a commercially available gas diffusion cell fitted with a microporous Teflon membrane to significantly reduce or eliminate potential interferences such as chlorine and oxidized forms of manganese. Detection limits of 0.03 mg/L ozone are possible with sensitivities and linear ranges comparable to the manual method. Selectivity is significantly improved and chlorine interference is reduced to 0.008 mg/L of apparent ozone for each part per million of chlorine present while oxidized manganese interference is completely eliminated. This method provides a sample throughput of 65 samples per hour. 30 references, 2 figures, 2 tables.

  20. Effective control of photomask surface chemical residuals through thermal treatment

    NASA Astrophysics Data System (ADS)

    Kang, Han-Byul; Kim, Jong-Min; Kim, Yong-Dae; Cho, Hyun-Joon; Choi, Sang-Soo

    2005-05-01

    We investigated the control of residual ions on the mask surface and the phase/transmission change rate by using thermal treatment after a conventional cleaning process. We hypothesized that the remaining sulfuric ions on the mask surface could combine with other ions and produce compounds during the thermal treatment. These compounds are easily removed by a hot D.I water rinse. Our study shows that the amount of remaining sulfuric ions is 250ng/mask when the mask has been thermally treated. The amount of sulfuric ions is substantially reduced compared to the results of other cleaning processes. Additionally we have found that the thermal treatment can be reduced varying the phase/trans value according to the cleaning cycle and the variation was stable even with a higher concentration of SC-1 solution.