Science.gov

Sample records for additive main effects

  1. Hydraulic and Geomorphic Effects of Large Woody Debris Additions in the Narraguagus Watershed, Coastal Maine

    NASA Astrophysics Data System (ADS)

    Johnson, E.; Snyder, N. P.

    2009-12-01

    Maine coastal rivers host the last remaining runs of endangered anadromous Atlantic salmon in the United States, whose populations have declined from ~500,000 returning adults in the 1880s to only ~1000 in 2000. Restoration projects focus on these rivers, and recent efforts involve adding large woody debris (LWD) to small tributaries to improve salmon rearing habitat. LWD changes the hydraulics and geomorphology of small streams by acting as a barrier to flow and resulting in decreased velocity zones, scour pools, and sediment storage and sorting. We quantify the effects of LWD additions in early August 2008 on hydraulics and substrate in Baker Brook, a west-flowing tributary of the Narraguagus River. Hydraulically, we focus on the treatment reach nearest the confluence with the Narraguagus River (Baker1). We study substrate in this and the upstream treatment location (Baker3). Both study locations are divided into two reaches, treatment (received cut wood) and control (did not receive cut wood). The reaches are further divided into 50 m sub-reaches based on gradient (1-2%). We seek to answer two research questions: (1) how much does mean velocity through the study sub-reaches change as a result of additions; and (2) does sediment storage and sorting result from the LWD additions? We measured reach-average velocities (Ureach) in Baker1 using the salt dilution method in May, July, August and October 2008 and May 2009. We use rating curves to compare the post-treatment to the pre-treatment Ureach-stage relationship. No reach-average change was quantified during the low-to-moderate flows we observed. We found a localized change in cross-sectionally averaged velocity (U⊥) measured with a flow meter in one sub-reach, but this is because an added tree intersected the cross-section where measurements were recorded. We quantified pre- and post-treatment sub-reach substrate median grain size (D50) with intensive clast counts in July 2008 and May 2009. Two of the three

  2. Additively Manufactured Main Fuel Valve Housing

    NASA Technical Reports Server (NTRS)

    Eddleman, David; Richard, Jim

    2015-01-01

    Selective Laser Melting (SLM) was utilized to fabricate a liquid hydrogen valve housing typical of those found in rocket engines and main propulsion systems. The SLM process allowed for a valve geometry that would be difficult, if not impossible to fabricate by traditional means. Several valve bodies were built by different SLM suppliers and assembled with valve internals. The assemblies were then tested with liquid nitrogen and operated as desired. One unit was also burst tested and sectioned for materials analysis. The design, test results, and planned testing are presented herein.

  3. 20. MAIN ENTRANCE STAIRWAY AREA, 1913 ADDITION, LOOKING EASTNORTHEAST. AT ...

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

    20. MAIN ENTRANCE STAIRWAY AREA, 1913 ADDITION, LOOKING EAST-NORTHEAST. AT LEFT IS ENTRY FROM MAIN ENTRANCE VESTIBULE, AND AT RIGHT IS LANDING BETWEEN STAIR LEVELS LEADING TO SECOND FLOOR RECEPTION AREA - Underwriters' Laboratories, 207-231 East Ohio Street, Chicago, Cook County, IL

  4. 47. MAIN WAREHOUSE SECOND LEVEL ADDITION Second level was ...

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

    47. MAIN WAREHOUSE - SECOND LEVEL ADDITION Second level was added in 1941. Note the variety of building materials used in the wall: cement, bricks and finally cement blocks, with wood topping the entire wall. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

  5. Effects of Ammonium and Non-Ammonium Salt Additions on Methane Oxidation by Methylosinus trichosporium OB3b and Maine Forest Soils.

    PubMed

    King, G M; Schnell, S

    1998-01-01

    Additions of ammonium and non-ammonium salts inhibit atmospheric methane consumption by soil at salt concentrations that do not significantly affect the soil water potential. The response of soils to non-ammonium salts has previously raised questions about the mechanism of ammonium inhibition. Results presented here show that inhibition of methane consumption by non-ammonium salts can be explained in part by ion-exchange reactions: cations desorb ammonium, with the level of desorption varying as a function of both the cation and anion added; differential desorption results in differential inhibition levels. Differences in the extent of inhibition among ammonium salts can also be explained in part by the effects of anions on ammonium exchange. In contrast, only minimal effects of cations and anions are observed in liquid cultures of Methylosinus trichosporium OB3b. The comparable level of inhibition by equinormal concentrations of NH(4)Cl and (NH(4))(2)SO(4) and the insensitivity of salt inhibition to increasing methane concentrations (from 10 to 100 ppm) are of particular interest, since both of these patterns are in contrast to results for soils. The greater inhibition of methane consumption for NH(4)Cl than (NH(4))(2)SO(4) in soils can be attributed to increased ammonium adsorption by sulfate; increasing inhibition by non-ammonium salts with increasing methane concentrations can be attributed to desorbed ammonium and a physiological mechanism proposed previously for pure cultures.

  6. Effects of Ammonium and Non-Ammonium Salt Additions on Methane Oxidation by Methylosinus trichosporium OB3b and Maine Forest Soils†

    PubMed Central

    King, G. M.; Schnell, S.

    1998-01-01

    Additions of ammonium and non-ammonium salts inhibit atmospheric methane consumption by soil at salt concentrations that do not significantly affect the soil water potential. The response of soils to non-ammonium salts has previously raised questions about the mechanism of ammonium inhibition. Results presented here show that inhibition of methane consumption by non-ammonium salts can be explained in part by ion-exchange reactions: cations desorb ammonium, with the level of desorption varying as a function of both the cation and anion added; differential desorption results in differential inhibition levels. Differences in the extent of inhibition among ammonium salts can also be explained in part by the effects of anions on ammonium exchange. In contrast, only minimal effects of cations and anions are observed in liquid cultures of Methylosinus trichosporium OB3b. The comparable level of inhibition by equinormal concentrations of NH4Cl and (NH4)2SO4 and the insensitivity of salt inhibition to increasing methane concentrations (from 10 to 100 ppm) are of particular interest, since both of these patterns are in contrast to results for soils. The greater inhibition of methane consumption for NH4Cl than (NH4)2SO4 in soils can be attributed to increased ammonium adsorption by sulfate; increasing inhibition by non-ammonium salts with increasing methane concentrations can be attributed to desorbed ammonium and a physiological mechanism proposed previously for pure cultures. PMID:16349485

  7. 49 CFR 218.105 - Additional operational requirements for hand-operated main track switches.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-operated main track switches. 218.105 Section 218.105 Transportation Other Regulations Relating to... PRACTICES Handling Equipment, Switches, and Fixed Derails § 218.105 Additional operational requirements for hand-operated main track switches. (a) Each railroad shall adopt and comply with an operating...

  8. 49 CFR 218.105 - Additional operational requirements for hand-operated main track switches.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...-operated main track switches. 218.105 Section 218.105 Transportation Other Regulations Relating to... PRACTICES Handling Equipment, Switches, and Fixed Derails § 218.105 Additional operational requirements for hand-operated main track switches. (a) Each railroad shall adopt and comply with an operating...

  9. The Mozart Effect: Additional Data.

    PubMed

    Hughes, John R.

    2002-04-01

    After the review of the Mozart effect was published in this journal (Hughes JR. Epilepsy Behav 2001;2:369-417), additional data from the music of Haydn and Liszt have been analyzed that may account for the decrease in seizure activity originally reported during Mozart music. Even with these added data Mozart music continued to score significantly higher than the selections from the other six composers in one of the important characteristics of this music, namely, the repetition of the melody. However Haydn's values were second highest among Mozart, J. S. Bach, Wagner, Beethoven, Chopin, and Liszt.

  10. 49 CFR 218.105 - Additional operational requirements for hand-operated main track switches.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Additional operational requirements for hand... hand-operated main track switches. (a) Each railroad shall adopt and comply with an operating rule... the requirements of this section. (b) Designating switch position. The normal position of a...

  11. 49 CFR 218.105 - Additional operational requirements for hand-operated main track switches.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Additional operational requirements for hand... hand-operated main track switches. (a) Each railroad shall adopt and comply with an operating rule... the requirements of this section. (b) Designating switch position. The normal position of a...

  12. 49 CFR 218.105 - Additional operational requirements for hand-operated main track switches.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Additional operational requirements for hand... hand-operated main track switches. (a) Each railroad shall adopt and comply with an operating rule... the requirements of this section. (b) Designating switch position. The normal position of a...

  13. 76 FR 21613 - Gypsy Moth Generally Infested Areas; Additions in Indiana, Maine, Ohio, Virginia, West Virginia...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-18

    ... Inspection Service 7 CFR Part 301 Gypsy Moth Generally Infested Areas; Additions in Indiana, Maine, Ohio...: Interim rule and request for comments. SUMMARY: We are amending the gypsy moth regulations by adding areas... areas based on the detection of infestations of gypsy moth in those areas. As a result of this...

  14. Additive Effects on Asymmetric Catalysis.

    PubMed

    Hong, Liang; Sun, Wangsheng; Yang, Dongxu; Li, Guofeng; Wang, Rui

    2016-03-23

    This review highlights a number of additives that can be used to make asymmetric reactions perfect. Without changing other reaction conditions, simply adding additives can lead to improved asymmetric catalysis, such as reduced reaction time, improved yield, or/and increased selectivity.

  15. 76 FR 60358 - Gypsy Moth Generally Infested Areas; Additions in Indiana, Maine, Ohio, Virginia, West Virginia...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-29

    ... Animal and Plant Health Inspection Service 7 CFR Part 301 Gypsy Moth Generally Infested Areas; Additions... detection of infestations of gypsy moth in those areas. The interim rule was necessary to prevent the artificial spread of the gypsy moth to noninfested areas of the United States. DATES: Effective on...

  16. ProPhenol-Catalyzed Asymmetric Additions by Spontaneously Assembled Dinuclear Main Group Metal Complexes

    PubMed Central

    2016-01-01

    magnesium ProPhenol complex was used to facilitate enantioselective diazoacetate aldol reactions with aryl, α,β-unsaturated, and aliphatic aldehydes. The utility of bimetallic ProPhenol catalysts was extended to asymmetric additions with a wide range of substrate combinations. Effective pronucleophiles include oxazolones, 2-furanone, nitroalkanes, pyrroles, 3-hydroxyoxindoles, alkynes, meso-1,3-diols, and dialkyl phosphine oxides. These substrates were found to be effective with a number of electrophiles, including aldehydes, imines, nitroalkenes, acyl silanes, vinyl benzoates, and α,β-unsaturated carbonyls. A truly diverse range of enantioenriched compounds have been prepared using the ProPhenol ligand, and the commercial availability of both ligand enantiomers makes it ideally suited for the synthesis of complex molecules. To date, enantioselective ProPhenol-catalyzed reactions have been used in the synthesis of more than 20 natural products. PMID:25650587

  17. Environmental Assessment: Construct a CDC Main Entry Addition at Grand Forks Air Force Base

    DTIC Science & Technology

    2006-03-01

    North Dakota. Purpose and Need: The purpose of the proposed action is to construct an addition to the northeast end of the Child Development Center...families. There is a companion proposal to repair the administrative support area in the northeast end of the Child Development Center (CDC), Bldg...action is to construct an addition to the northeast end of the Child Development Center (CDC), Building 168 at 1683 J St. The addition will provide

  18. Effect of glutathione addition in sparkling wine.

    PubMed

    Webber, Vanessa; Dutra, Sandra Valduga; Spinelli, Fernanda Rodrigues; Marcon, Ângela Rossi; Carnieli, Gilberto João; Vanderlinde, Regina

    2014-09-15

    This study aims to evaluate the effect of the addition of glutathione (GSH) on secondary aromas and on the phenolic compounds of sparkling wine elaborated by traditional method. It was added 10 and 20 mg L(-1) of GSH to must and to base wine. The determination of aroma compounds was performed by gas chromatography. Phenolic compounds and glutathione content were analyzed by high performance liquid chromatography. Sparkling wines with addition of GSH to must showed lower levels of total phenolic compounds and hydroxycinnamic acids. Furthermore, the sparkling wine with addition of GSH to must showed higher levels of 2-phenylethanol, 3-methyl-1-butanol and diethyl succinate, and lower concentrations of ethyl decanoate, octanoic and decanoic acids. The GSH addition to the must show a greater influence on sparkling wine than to base wine, however GSH addition to base wine seems retain higher SO2 free levels. The concentration of GSH added showed no significant difference.

  19. The Additive Effects of Choice and Control.

    ERIC Educational Resources Information Center

    Karbowski, Joseph; And Others

    In separate research studies, students who were given a choice of learning materials or who had control over aversive noise, demonstrated higher motivation and better task performance. To investigate the additive effects of choice and control on perception of control, 80 male and female college students participated in a 2 (choice vs. no-choice) X…

  20. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  1. Toxic effect of biosurfactant addition on the biodegradation of phenanthrene.

    PubMed

    Shin, Kyung-Hee; Ahn, Yeonghee; Kim, Kyoung-Woong

    2005-11-01

    The effect of the biosurfactant rhamnolipid on phenanthrene biodegradation and cell growth of phenanthrene degraders was investigated. To compare the effect of rhamnolipid addition, two bacterial strains, 3Y and 4-3, which were isolated from a diesel-contaminated site in Korea, were selected. Without the biosurfactant, large amounts of phenanthrene were degraded with both strains at neutral pH, with higher rates of phenanthrene degradation when the cell growth was higher. Upon the addition of 240 mg/L rhamnolipid, the phenanthrene degradation and optical density were reduced, with this inhibitory effect similar for both 3Y and 4-3. To explain this inhibition, the cell growths of both strains were monitored with various concentrations of rhamnolipid, which showed significant toxic effects toward strain 3Y, but was nontoxic toward 4-3. Combining the inhibitory and toxicity results with regard to the biodegradation, different mechanisms can be suggested for each strain. In the biodegradation experiments, the toxicity of rhamnolipid itself mainly was responsible for the inhibitory effect in the case of 3Y, whereas the toxicity of solubilized phenanthrene or the increased toxicity of rhamnolipid in the presence of solubilized phenanthrene could have resulted in the inhibitory effect in the case of 4-3. This study demonstrated that the effectiveness of biosurfactant-enhanced biodegradation can be significantly different depending on the strain, and the toxicity of the biosurfactant should be considered as an important factor.

  2. Effects of precommercial thinning on snowshoe hares in Maine

    USGS Publications Warehouse

    Homyack, J.A.; Harrison, D.J.; Krohn, W.B.

    2007-01-01

    Snowshoe hares (Lepus americanus) are an important prey species and a dominant herbivore across much of their North American range, and researchers have questioned the influences of forestry practices that alter habitat for hares and the potential community-level effects on carnivores. We examined the effects of precommercial thinning (PCT) from 1 to 11 years posttreatment on snowshoe hares. In the commercial forests of northern Maine, USA, we counted and cleared hare pellets twice a year during 2001 and 2002 on >46 km of pellet transects across 30 regenerating conifer stands (17 treated with PCT) previously treated with an aerial application of herbicide. We compared densities of snowshoe hare pellets among 3 development classes with (1 yr after thinning, 6 yr after thinning, and 11 yr after thinning) and without thinning (stands with a similar history of clearcut and herbicide treatment but no thinning). During both years, densities of hares were lower in stands treated with PCT than in similar unthinned stands across the 3 development classes and during both leaf-off and leaf-on seasons (P < 0.001). Within both thinned and unthinned stands, hare density was greatest in stands in the 1-year development class when compared to the 6-year and 11-year development classes, but a statistical difference (P = 0.048) among classes was evident only during leaf-off seasons. Precommercial thinning was associated with densities of snowshoe hares that were approximately half of those in similar unthinned stands up to at least 11 years posttreatment; however, thinned stands may retain densities of hares greater than stands managed using other forest harvesting regimes. Our results apply to core portions of stands with crop trees spaced at 1.8-2.4-m intervals following complete overstory removal and herbicide treatment. We advocate caution when applying our results to other thinning regimes or across broader spatial scales.

  3. Eleven-year response of foliar chemistry to chronic nitrogen and sulfur additions at the Bear Brooks Watershed in Maine

    SciTech Connect

    Jose Alexander Elvir; Gregory J. White

    2005-06-01

    The foliar chemistry of sugar maple (Acer saccharum Marsh.), American beech (Fagus grandifolia Ehrh.), and red spruce (Picea rubens Sarg.) was studied from 1993 to 2003 at the Bear Brook Watershed in Maine (BBWM). The BBWM is a paired-watershed forest ecosystem study, with one watershed treated bimonthly since 1989 with ammonium sulfate ((NH4)2SO4) at a rate of 25.2 kg N·ha–1·year–1. Foliar N concentrations were higher in all tree species within the treated watershed compared with trees within the reference watershed. Foliar Ca and Mg concentrations were lower in American beech and red spruce within the treated watershed. There were no significant differences in foliar K concentrations between watersheds. Foliar P and Mn concentration differences between watersheds were inconsistent among years. Differences in foliar N concentrations between watersheds declined over time in sugar maple but not in red spruce or American beech. Differences in foliar Ca and Mg concentrations between the treated and reference watersheds increased over time for American beech and red spruce, primarily because of a consistent decline in concentrations of these nutrients in trees within the treated watershed. No temporal trends in foliar Ca and Mg concentration differences between watersheds were observed for sugar maple.

  4. Effectiveness of Low Temperature Additives for Biodiesel Blends

    DTIC Science & Technology

    2012-06-30

    UNCLASSIFIED EFFECTIVENESS OF LOW TEMPERATURE ADDITIVES FOR BIODIESEL BLENDS INTERIM REPORT TFLRF No. 428 by Steven R...Do not return it to the originator. UNCLASSIFIED UNCLASSIFIED EFFECTIVENESS OF LOW TEMPERATURE ADDITIVES FOR BIODIESEL BLENDS...17-2010 – 06-30-2012 4. TITLE AND SUBTITLE Effectiveness of Low Temperature Additives for Biodiesel Blends 5a. CONTRACT NUMBER W56HZV-09-C-0100

  5. Effectiveness of Ninth-Grade Physics in Maine: Conceptual Understanding

    NASA Astrophysics Data System (ADS)

    O'Brien, Michael J.; Thompson, John R.

    2009-04-01

    The Physics First movement—teaching a true physics course to ninth-grade students—is gaining popularity in high schools. There are several different rhetorical arguments for and against this movement, and it is quite controversial in physics education. However, there is no actual evidence to assess the success, or failure, of this substantial shift in the science teaching sequence. We have undertaken a comparison study of physics classes taught in ninth- and 12th-grade classes in Maine. Comparisons of student understanding and gains with respect to mechanics concepts were made with excerpts from well-known multiple-choice surveys and individual student interviews. Results indicate that both populations begin physics courses with similar content knowledge and specific difficulties, but when learning concepts, ninth-graders are more sensitive to the instructional method used.

  6. Implementation of Complexity Analyzing Based on Additional Effect

    NASA Astrophysics Data System (ADS)

    Zhang, Peng; Li, Na; Liang, Yanhong; Liu, Fang

    According to the Complexity Theory, there is complexity in the system when the functional requirement is not be satisfied. There are several study performances for Complexity Theory based on Axiomatic Design. However, they focus on reducing the complexity in their study and no one focus on method of analyzing the complexity in the system. Therefore, this paper put forth a method of analyzing the complexity which is sought to make up the deficiency of the researches. In order to discussing the method of analyzing the complexity based on additional effect, this paper put forth two concepts which are ideal effect and additional effect. The method of analyzing complexity based on additional effect combines Complexity Theory with Theory of Inventive Problem Solving (TRIZ). It is helpful for designers to analyze the complexity by using additional effect. A case study shows the application of the process.

  7. Effect of additives on the purification of urease

    NASA Astrophysics Data System (ADS)

    Yu, X.; Wang, J.; Ulrich, J.

    2015-12-01

    The effect of additives on the purification of proteins was investigated. The target protein studied here is the enzyme urease. Studies on the purification of urease from jack bean meal were carried out. 32% (v/v) acetone was utilized to extract urease from the jack bean meal. Further purification by crystallization with the addition of 2-mercaptoethanol and EDTA disodium salt dehydrate was carried out. It was found out that the presence of additives can affect the selectivity of the crystallization. Increases in both purity and yield of the urease after crystallization were observed in the presence of additives, which were proven using both SDS-PAGE and activity. Urease crystals with a yield of 69.9% and a purity of 85.1% were obtained in one crystallization step in the presence of additives. Furthermore, the effect of additives on the thermodynamics and kinetics of urease crystallization was studied.

  8. Progress on electron cloud effects calculations for the FNAL main injector

    SciTech Connect

    Furman, Miguel A; Sonnad, Kiran G.; Furman, Miguel A.; Vay, Jean-Luc

    2008-06-09

    We have studied the response of the beam to an electron cloud for the Fermilab Main Injector using the Quasistatic Model [1] implemented into the particle-in-cell code Warp [2]. Specifically, we have addressed the effects due to varying the beam intensity, electron cloud density and chromaticity. In addition, we have estimated the contribution to emittance evolution due to beam space-charge effects. We have carried out a comparison between how the beam responds at injection energy and at top energy. We also present some results on the validation of the computational model, and report on progress towards improving the computational model.

  9. Polymer Photooxidation: An Experiment to Demonstrate the Effect of Additives.

    ERIC Educational Resources Information Center

    Allen, Norman S.; McKellar, John F.

    1979-01-01

    This undergraduate experiment shows that the inclusion of an appropriate additive can have a very marked effect on the physical properties of a polymer. The polymer used is polypropylene and the additives are 2-hydroxy-4-octyloxy-benzophenone and benzophenone. (BB)

  10. Effect of Fortification and Additives on Breast Milk Osmolality.

    PubMed

    Gupta, Vijay; Job, Victoria; Thomas, Niranjan

    2016-02-01

    This study evaluated the effect of fortification and commonly used additives on the osmolality of human milk. Osmolality after fortification with milk powder and human milk fortifier increased from 303 mOsmol/kg to 397 and 373 mOsmol/kg, respectively. The maximal increase in osmolality was seen with the addition of calcium gluconate.

  11. Effects of various additives on sintering of aluminum nitride

    NASA Technical Reports Server (NTRS)

    Komeya, K.; Inoue, H.; Tsuge, A.

    1982-01-01

    Effects of thirty additives on sintering A/N were investigated. The addition of alkali earth oxides and rare earth oxides gave fully densified aluminum nitride. This is due to the formation of nitrogen-containing aluminate liquid in the system aluminum nitride-alkali earth oxides or rare earth oxides. Microstructural studies of the sintered specimens with the above two types of additives suggested that the densification was due to the liquid phase sintering. Additions of silicon compounds resulted in poor densification by the formation of highly refractory compounds such as A/N polytypes.

  12. Interactive effects of nutrient additions and predation on infaunal communities

    USGS Publications Warehouse

    Posey, M.H.; Alphin, T.D.; Cahoon, L.; Lindquist, D.; Becker, M.E.

    1999-01-01

    Nutrient additions represent an important anthropogenic stress on coastal ecosystems. At moderate levels, increased nutrients may lead to increased primary production and, possibly, to increased biomass of consumers although complex trophic interactions may modify or mask these effects. We examined the influence of nutrient additions and interactive effects of trophic interactions (predation) on benthic infaunal composition and abundances through small-scale field experiments in 2 estuaries that differed in ambient nutrient conditions. A blocked experimental design was used that allowed an assessment of direct nutrient effects in the presence and absence of predation by epibenthic predators as well as an assessment of the independent effects of predation. Benthic microalgal production increased with experimental nutrient additions and was greater when infaunal abundances were lower, but there were no significant interactions between these factors. Increased abundances of one infaunal taxa, Laeonereis culveri, as well as the grazer feeding guild were observed with nutrient additions and a number of taxa exhibited higher abundances with predator exclusion. In contrast to results from freshwater systems there were no significant interactive effects between nutrient additions and predator exclusion as was predicted. The infaunal responses observed here emphasize the importance of both bottom-up (nutrient addition and primary producer driven) and top-down (predation) controls in structuring benthic communities. These processes may work at different spatial and temporal scales, and affect different taxa, making observation of potential interactive effects difficult.

  13. [Kinetic analysis of additive effect on desulfurization activity].

    PubMed

    Han, Kui-hua; Zhao, Jian-li; Lu, Chun-mei; Wang, Yong-zheng; Zhao, Gai-ju; Cheng, Shi-qing

    2006-02-01

    The additive effects of A12O3, Fe2O3 and MnCO3 on CaO sulfation kinetics were investigated by thermogravimetic analysis method and modified grain model. The activation energy (Ea) and the pre-exponential factor (k0) of surface reaction, the activation energy (Ep) and the pre-exponential factor (D0) of product layer diffusion reaction were calculated according to the model. Additions of MnCO3 can enhance the initial reaction rate, product layer diffusion and the final CaO conversion of sorbents, the effect mechanism of which is similar to that of Fe2O3. The method based isokinetic temperature Ts and activation energy can not estimate the contribution of additive to the sulfation reactivity, the rate constant of the surface reaction (k), and the effective diffusivity of reactant in the product layer (Ds) under certain experimental conditions can reflect the effect of additives on the activation. Unstoichiometric metal oxide may catalyze the surface reaction and promote the diffusivity of reactant in the product layer by the crystal defect and distinct diffusion of cation and anion. According to the mechanism and effect of additive on the sulfation, the effective temperature and the stoichiometric relation of reaction, it is possible to improve the utilization of sorbent by compounding more additives to the calcium-based sorbent.

  14. Effects of some polymeric additives on the cocrystallization of caffeine

    NASA Astrophysics Data System (ADS)

    Chung, Jihae; Kim, Il Won

    2011-11-01

    Effects of polymeric additives on the model cocrystallization were examined. The model cocrystal was made from caffeine and oxalic acid, and poly(ethylene glycol) (PEG), poly( L-lactide) (PLLA), poly(ɛ-caprolactone) (PCL), and poly(acrylic acid) (PAA) were the additives. The cocrystals were formed as millimeter-sized crystals without additives, and they became microcrystals with PLLA and PCL, and nanocrystals with PAA. XRD and IR revealed that the cocrystal structure was unchanged despite the strong effects of the additives on the crystal morphology, although some decrease in crystallinity was observed with PAA as confirmed by DSC. The DSC study also showed that the cocrystal melted and recrystallized to form α-caffeine upon heating. The present study verified that the polymeric additives can be utilized to modulate the size and morphology of the cocrystals without interfering the intermolecular interactions essential to the integrity of the cocrystal structures.

  15. Ecotoxicological effects of activated carbon addition to sediments.

    PubMed

    Jonker, Michiel T O; Suijkerbuijk, Martin P W; Schmitt, Heike; Sinnige, Theo L

    2009-08-01

    Activated carbon (AC) addition is a recently developed technique for the remediation of sediments and soils contaminated with hydrophobic organic chemicals. Laboratory and field experiments have demonstrated that the addition of 3-4% of AC can reduce aqueous concentrations and the bioaccumulation potential of contaminants. However, one aspect of the technique that has hardly received any attention is the possible occurrence of secondary, eco(toxico)logical effects, i.e., effects of AC addition on the health, behavior, and habitat quality of local organisms. In the present study, several ecotoxicological effects were investigated in AC-water and AC-enriched (0-25%) sediment systems. It was demonstrated that (i) powdered activated carbons can be toxic to aquatic invertebrates (Lumbriculus variegatus, Daphnia magna, and Corophium volutator) based on different mechanisms and preferably should be washed prior to application; (ii) Asellus aquaticus and Corophium volutator may physically avoid AC-enriched sediments; (iii) exposure of Lumbriculus variegatus to AC-enriched sediments lead to a time and dose-dependent reduction in the worms' lipid content, which was most probably caused by the observation that (iv) worm egestion rates decreased drastically upon AC addition, indicating that the presence of AC disturbed feeding behavior; and (v) there were no obvious effects on the microbiological community structure. All in all, these results suggest potential ecotoxicological effects of powdered AC addition and stress the need for a detailed further investigation of secondary effects of the technique, prior to any large-scale field application.

  16. Cost-Effectiveness Analysis of the Residential Provisions of the 2015 IECC for Maine

    SciTech Connect

    Mendon, Vrushali V.; Zhao, Mingjie; Taylor, Zachary T.; Poehlman, Eric A.

    2016-02-15

    The 2015 IECC provides cost-effective savings for residential buildings in Maine. Moving to the 2015 IECC from the 2009 IECC base code is cost-effective for residential buildings in all climate zones in Maine.

  17. The effect of chemical additives on the synthesis of ethanol

    SciTech Connect

    Chuang, S.S.C.

    1990-11-01

    The objective of this research is to elucidate the role of additives on the ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies of NO adsorption, reaction probing, study state rate measurement, and transient kinetic study. A better understanding of the role of additive on the synthesis reaction may allow them to use chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from syngas. 49 refs., 6 figs., 3 tabs.

  18. The effect of chemical additives on the synthesis of ethanol

    SciTech Connect

    Chuang, S.S.C.

    1990-04-09

    The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies of NO adsorption, reaction probing, study state rate measurement, and transient kinetic study. A better understanding of the role of additive on the synthesis reaction may allow us to use chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from syngas.

  19. The effect of chemical additives on the synthesis of ethanol

    SciTech Connect

    Chuang, S.S.C.

    1990-07-01

    The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies of NO adsorption, reaction probing, study state rate measurement, and transient kinetic study. A better understanding of the role of additive on the synthesis reaction may allow us to use chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from syngas.

  20. Study on thermal effects & sulfurized additives, in lubricating greases

    NASA Astrophysics Data System (ADS)

    Shah, Ami Atul

    Lithium Base grease constitutes about 50% of market. The greases are developed to be able to work in multiple working conditions and have longer working life. Greases with extreme pressure additives and anti-wear additives have been developed as a solution to many of the applications. These developed greases are tested under ASTM D2266 testing conditions to meet the requirements. The actual working conditions, although, differ than the real testing conditions. The loading, speed and temperature conditions can be more harsh, or fluctuating in nature. The cyclic nature of the parameters cannot be directly related to the test performance. For this purpose studies on the performance under spectrum loading, variable speed and fluctuating temperature must be performed. This study includes tests to understand the effect of thermal variation on some of the most commonly used grease additives that perform well under ASTM D2266 testing conditions. The studied additives include most widely used industrial extreme pressure additive MoS2. Performance of ZDDP which is trying to replace MoS2 in its industrial applications has also been studied. The tests cover study of extreme pressure, anti-wear and friction modifier additives to get a general idea on the effects of thermal variation in three areas. Sulphur is the most common extreme pressure additive. Sulphur based MoS 2 is extensively used grease additive. Study to understand the tribological performance of this additive through wear testing and SEM/EDX studies has been done. This performance is also studied for other metallic sulfides like WS2 and sulphur based organic compound. The aim is to study the importance of the type of bond that sulphur shares in its additive's structure on its performance. The MoS2 film formation is found to be on the basis of the FeS formation on the substrate and protection through sacrificial monolayer deposition of the MoS2 sheared structure. The free Mo then tends to oxidise. An attempt to

  1. A complete solution for dissecting pure main and epistatic effects of QTL in triple testcross design.

    PubMed

    He, Xiao-Hong; Zhang, Yuan-Ming

    2011-01-01

    Epistasis plays an important role in genetics, evolution and crop breeding. To detect the epistasis, triple test cross (TTC) design had been developed several decades ago. Classical procedures for the TTC design use only linear transformations Z(1), Z(2) and Z(3), calculated from the TTC family means of quantitative trait, to infer the nature of the collective additive, dominance and epistatic effects of all the genes. Although several quantitative trait loci (QTL) mapping approaches in the TTC design have been developed, these approaches do not provide a complete solution for dissecting pure main and epistatic effects. In this study, therefore, we developed a two-step approach to estimate all pure main and epistatic effects in the F(2)-based TTC design under the F(2) and F(∞) metric models. In the first step, with Z(1) and Z(2) the augmented main and epistatic effects in the full genetic model that simultaneously considered all putative QTL on the whole genome were estimated using empirical Bayes approach, and with Z(3) three pure epistatic effects were obtained using two-dimensional genome scans. In the second step, the three pure epistatic effects obtained in the first step were integrated with the augmented epistatic and main effects for the further estimation of all other pure effects. A series of Monte Carlo simulation experiments has been carried out to confirm the proposed method. The results from simulation experiments show that: 1) the newly defined genetic parameters could be rightly identified with satisfactory statistical power and precision; 2) the F(2)-based TTC design was superior to the F(2) and F(2:3) designs; 3) with Z(1) and Z(2) the statistical powers for the detection of augmented epistatic effects were substantively affected by the signs of pure epistatic effects; and 4) with Z(3) the estimation of pure epistatic effects required large sample size and family replication number. The extension of the proposed method in this study to other

  2. Viscous flow effects on hydrogen leaks from cracks in the Orbiter Challenger main engines

    NASA Technical Reports Server (NTRS)

    Goodrich, W. D.

    1984-01-01

    An analytical model was developed to provide additional insight and understanding of the factors that influence the simulation and prediction of leak rates from small cracks in pressurized containers. Specifically, the analysis was aimed at developing an analytical model capable of predicting the hydrogen leak rates from a crack in the combustion chamber coolant discharge manifold on main engine 1 of the Orbiter Challenger that was discovered during flight readiness firings 1 and 2. This model was based on viscous pipe flow analyses and calibrated for the crack geometry by using helium leak-rate data obtained from both low- and high-pressure tests used to simulate the flight readiness firing test conditions. In addition, this model includes the effects of crack width changes caused by different working stresses associated with the different test conditions. Because of the combination of the small crack dimensions and the wide range of pressures used for the test conditions, either laminar or turbulent viscous effects dominated the flows at all test conditions. This model was used to illustrate the sensitivity of the predicted leak rates to considerations of test conditions, viscous flow effects, and geometric features of the crack. In addition, the model was certified by comparing the hydrogen leak-rate prediction for the flight readiness firing test condition to the actual measured leak rate. The prediction was within 9 percent of the measured value.

  3. The effect of one additional driver mutation on tumor progression.

    PubMed

    Reiter, Johannes G; Bozic, Ivana; Allen, Benjamin; Chatterjee, Krishnendu; Nowak, Martin A

    2013-01-01

    Tumor growth is caused by the acquisition of driver mutations, which enhance the net reproductive rate of cells. Driver mutations may increase cell division, reduce cell death, or allow cells to overcome density-limiting effects. We study the dynamics of tumor growth as one additional driver mutation is acquired. Our models are based on two-type branching processes that terminate in either tumor disappearance or tumor detection. In our first model, both cell types grow exponentially, with a faster rate for cells carrying the additional driver. We find that the additional driver mutation does not affect the survival probability of the lesion, but can substantially reduce the time to reach the detectable size if the lesion is slow growing. In our second model, cells lacking the additional driver cannot exceed a fixed carrying capacity, due to density limitations. In this case, the time to detection depends strongly on this carrying capacity. Our model provides a quantitative framework for studying tumor dynamics during different stages of progression. We observe that early, small lesions need additional drivers, while late stage metastases are only marginally affected by them. These results help to explain why additional driver mutations are typically not detected in fast-growing metastases.

  4. Tin nanoparticles as an effective conductive additive in silicon anodes

    PubMed Central

    Zhong, L.; Beaudette, C.; Guo, J.; Bozhilov, K.; Mangolini, L.

    2016-01-01

    We have found that the addition of tin nanoparticles to a silicon-based anode provides dramatic improvements in performance in terms of both charge capacity and cycling stability. Using a simple procedure and off-the-shelf additives and precursors, we developed a structure in which the tin nanoparticles are segregated at the interface between the silicon-containing active layer and the solid electrolyte interface. Even a minor addition of tin, as small as ∼2% by weight, results in a significant decrease in the anode resistance, as confirmed by electrochemical impedance spectroscopy. This leads to a decrease in charge transfer resistance, which prevents the formation of electrically inactive “dead spots” in the anode structure and enables the effective participation of silicon in the lithiation reaction. PMID:27484849

  5. Effectiveness of various organometallics as antiwear additives in mineral oil

    NASA Technical Reports Server (NTRS)

    Buckley, D. H.

    1977-01-01

    Sliding friction experiments were conducted with 1045 steel contacting 302 stainless steel and lubricated with various organometallics in mineral oil. Auger emission spectroscopy was used to determine the element present in the wear contact zone. The results indicate that there are organometallics which are as effective an antiwear additives as the commonly used zinc dialkyl dithiophosphate. These include dimethyl cadmium, triphenyl lead thiomethoxide, and triphenyl tin chloride. The additives were examined in concentrations to 1 weight percent. With dimethyl cadmium at concentrations of 0.5 weight percent and above, cadmium was detected in the contact zone. Coincident with the detection of cadmium, a marked decrease in the friction coefficient was observed. All additives examined reduced friction, but only the aforementioned reduced wear to a level comparable to that observed with zinc dialkyl dithiophosphate.

  6. Modulation of additive and interactive effects by trial history revisited.

    PubMed

    Masson, Michael E J; Rabe, Maximilian M; Kliegl, Reinhold

    2017-04-01

    Masson and Kliegl (Journal of Experimental Psychology: Learning, Memory, and Cognition, 39, 898-914, 2013) reported evidence that the nature of the target stimulus on the previous trial of a lexical decision task modulates the effects of independent variables on the current trial, including additive versus interactive effects of word frequency and stimulus quality. In contrast, recent reanalyses of previously published data from experiments that, unlike the Masson and Kliegl experiments, did not include semantic priming as a factor, found no evidence for modulation of additive effects of frequency and stimulus quality by trial history (Balota, Aschenbrenner, & Yap, Journal of Experimental Psychology: Learning, Memory, and Cognition, 39, 1563-1571, 2013; O'Malley & Besner, Journal of Experimental Psychology: Learning, Memory, and Cognition, 34, 1400-1411, 2013). We report two experiments that included semantic priming as a factor and that attempted to replicate the modulatory effects found by Masson and Kliegl. In neither experiment was additivity of frequency and stimulus quality modulated by trial history, converging with the findings reported by Balota et al. and O'Malley and Besner. Other modulatory influences of trial history, however, were replicated in the new experiments and reflect potential trial-by-trial alterations in decision processes.

  7. EFFECT OF A WHOLE-CATCHMENT N ADDITION ON STREAM DETRITUS PROCESSING

    EPA Science Inventory

    The Bear Brook Watershed in Maine (BBWM) is a paired catchment study investigating ecosystem effects of N and S deposition. Because of the decade long (NH4)2SO4 addition, the treatment catchment has higher stream NO3 and enriched foliar N concentrations compared to the reference ...

  8. Effects of amino acid additives during hemodialysis of children.

    PubMed

    Abitbol, C L; Mrozinska, K; Mandel, S; McVicar, M; Wapnir, R A

    1984-01-01

    The intradialytic losses into the dialysate of free amino acids (AA) and alpha-amino nitrogen were determined during the dialysis of three children. Variations in plasma AA were determined pre- and postdialysis. The effect of these losses with the addition of an Abbott General Amino Acid Mixture to the dialysate in concentrations of 8.5, 17, and 34 mg/100 ml was studied. The major determinant of AA losses was the plasma concentration of the AA before beginning the dialysis treatment. Dialysance of individual AA varied inversely with their molecular weights. A zero flux of alpha-amino nitrogen occurred at a derived concentration of 22 mg/100 ml of the AA additive in the dialysate. Plasma concentrations of nonessential amino acids were little affected by the dialysate additive. In contrast, total essential amino acid nitrogen which fell during baseline dialyses showed significant improvement when the AA solution was added to the dialysate. This study suggests that the addition of AA to the dialysate bath may be effective in decreasing AA nitrogen losses during dialysis.

  9. Survival of free and microencapsulated Bifidobacterium: effect of honey addition.

    PubMed

    Favarin, Luciana; Laureano-Melo, Roberto; Luchese, Rosa Helena

    2015-01-01

    This study evaluated the effect of honey addition on the viability of free and emulsion encapsulated cells of two strains of Bifidobacterium that underwent simulation of human upper gastrointestinal transit. In the control condition, without honey, free cells were drastically reduced after exposure to gastrointestinal conditions. The reduction was more pronounced with Bifidobacterium J7 of human origin. On the other hand, when cells were encapsulated, the viability reduction was higher for strain Bifidobacterium Bb12. The microencapsulation improved the viability maintenance of both Bifidobacterium strains, in recommended amounts for probiotic activity, after exposure to simulated gastrointestinal conditions. Moreover, suspending free cells of both Bifidobacterium strains in honey solutions resulted in a protective effect, equivalent to the plain microencapsulation with sodium alginate 3%. It is concluded that microencapsulation and the addition of honey improved the ability of Bifidobacterium to tolerate gastrointestinal conditions in vitro.

  10. Percolation phenomenon in mixed reverse micelles: the effect of additives.

    PubMed

    Paul, Bidyut K; Mitra, Rajib K

    2006-03-01

    The conductivity of AOT/IPM/water reverse micellar systems as a function of temperature, has been found to be non-percolating at three different concentrations (100, 175 and 250 mM), while the addition of nonionic surfactants [polyoxyethylene(10) cetyl ether (Brij-56) and polyoxyethylene(20) cetyl ether (Brij-58)] to these systems exhibits temperature-induced percolation in conductance in non-percolating AOT/isopropyl myristate (IPM)/water system at constant compositions (i.e., at fixed total surfactant concentration, omega and X(nonionic)). The influence of total surfactant concentration (micellar concentration) on the temperature-induced percolation behaviors of these systems has been investigated. The effect of Brij-58 is more pronounced than that of Brij-56 in inducing percolation. The threshold percolation temperature, Tp has been determined for these systems in presence of additives of different molecular structures, physical parameters and/or interfacial properties. The additives have shown both assisting and resisting effects on the percolation threshold. The additives, bile salt (sodium cholate), urea, formamide, cholesteryl acetate, cholesteryl benzoate, toluene, a triblock copolymer [(EO)13(PO)30(EO)13, Pluronic, PL64], polybutadiene, sucrose esters (sucrose dodecanoates, L-1695 and sucrose monostearate S-1670), formamide distinctively fall in the former category, whereas sodium chloride, cholesteryl palmitate, crown ether, ethylene glycol constitute the latter for both systems. Sucrose dodecanoates (L-595) had almost marginal effect on the process. The observed behavior of these additives on the percolation phenomenon has been explained in terms of critical packing parameter and/or other factors, which influence the texture of the interface and solution properties of the mixed reverse micellar systems. The activation energy, Ep for the percolation process has been evaluated. Ep values for the AOT/Brij-56 systems have been found to be lower than those of

  11. Effect of water on overbased sulfonate engine oil additives.

    PubMed

    Tavacoli, J W; Dowding, P J; Steytler, D C; Barnes, D J; Routh, A F

    2008-04-15

    The presence and effect of water on calcium carbonate nanoparticles used in engine additives, stabilized with a sulfonate surfactant, is investigated using small-angle neutron scattering, dynamic light scattering, Fourier transform infrared spectroscopy, and rheometry. These techniques provide complementary data that suggests the formation of a layer of water around the core of the particles ensuring continued colloidal stability yet increasing the dispersion viscosity. Through the use of small-angle neutron scattering, the dimensions of this layer have been quantified to effectively one or two water molecules in thickness. The lack of a significant electrostatic repulsion is evidence that the water layer is insufficient to cause major dissociation of surface ions.

  12. Antiinflammatory, Antioxidant, and Immunomodulatory Effects of Crocus sativus L. and its Main Constituents.

    PubMed

    Boskabady, Mohammad Hossein; Farkhondeh, Tahereh

    2016-07-01

    Crocus sativus L. (C. sativus), commonly known as saffron, is used as a food additive, preservative, and medicinal herb. Traditionally, it has been used as an alternative treatment for different diseases. C. sativus' medicinal effects are related to its major constituents like crocins, crocetin, and safranal. According to the literature, C. sativus and its constituents could be considered as an effective treatment for neurodegenerative disorders, coronary artery diseases, asthma, bronchitis, colds, fever, diabetes, and so on. Recently, numerous studies have reported such medicinal properties and found that the underlying mechanisms of action may be mediated by antioxidant, inflammatory, and immunomodulatory effects. C. sativus enhances the antioxidant capacity and acts as a free radical scavenger. As an antiinflammatory and immunomodulatory agent, it modulates inflammatory mediators, humoral immunity, and cell-mediated immunity responses. This review highlights in vitro and animal findings regarding antiinflammatory, antioxidant, and immunomodulatory effects of C. sativus and its constituents. Present review found that the C. sativus and its main constituents such as safranal, crocins, and crocetin could be effective against various diseases because of their antioxidant, anti-inflammation, and immunomodulatory effects. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Effect of additives on physicochemical properties in amorphous starch matrices.

    PubMed

    Liang, Jun; Wang, Simon; Ludescher, Richard D

    2015-03-15

    The effect of the addition of non-reducing sugars or methylcellulose on the matrix physical properties and rate of non-enzymatic browning (NBR) between exogenous glucose+lysine in a starch-based glassy matrix were studied, using the methods of luminescence and FTIR. Amorphous starch-based matrices were formulated by rapidly dehydrating potato starch gel mixed with additives at weight ratios of 7:93 (additive:starch). Data on the phosphorescence emission energy and lifetime from erythrosin B dispersed in the matrices indicated that sugars decreased starch matrix mobility in a Tg-dependent manner, except for trehalose that interacted with starch in a unique mode, while methylcellulose, the additive with the highest Tg, increased the molecular mobility. Using FTIR, we found that methylcellulose decreased the strength of hydrogen bond network and sugars enhanced the hydrogen bond strength in the order: trehalose>maltitol>sucrose. Comparing those changes with the rate of NBR between exogenous glucose+lysine, we suggest that NBR rates are primarily influenced by matrix mobility, which is modulated by the hydrogen bond network, and interactions among components.

  14. Stellar Diameters and Temperatures. III. Main-sequence A, F, G, and K Stars: Additional High-precision Measurements and Empirical Relations

    NASA Astrophysics Data System (ADS)

    Boyajian, Tabetha S.; von Braun, Kaspar; van Belle, Gerard; Farrington, Chris; Schaefer, Gail; Jones, Jeremy; White, Russel; McAlister, Harold A.; ten Brummelaar, Theo A.; Ridgway, Stephen; Gies, Douglas; Sturmann, Laszlo; Sturmann, Judit; Turner, Nils H.; Goldfinger, P. J.; Vargas, Norm

    2013-07-01

    Based on CHARA Array measurements, we present the angular diameters of 23 nearby, main-sequence stars, ranging from spectral types A7 to K0, 5 of which are exoplanet host stars. We derive linear radii, effective temperatures, and absolute luminosities of the stars using Hipparcos parallaxes and measured bolometric fluxes. The new data are combined with previously published values to create an Angular Diameter Anthology of measured angular diameters to main-sequence stars (luminosity classes V and IV). This compilation consists of 125 stars with diameter uncertainties of less than 5%, ranging in spectral types from A to M. The large quantity of empirical data is used to derive color-temperature relations to an assortment of color indices in the Johnson (BVR J I J JHK), Cousins (R C I C), Kron (R K I K), Sloan (griz), and WISE (W 3 W 4) photometric systems. These relations have an average standard deviation of ~3% and are valid for stars with spectral types A0-M4. To derive even more accurate relations for Sun-like stars, we also determined these temperature relations omitting early-type stars (T eff > 6750 K) that may have biased luminosity estimates because of rapid rotation; for this subset the dispersion is only ~2.5%. We find effective temperatures in agreement within a couple of percent for the interferometrically characterized sample of main-sequence stars compared to those derived via the infrared flux method and spectroscopic analysis.

  15. Cantaloupe melon peroxidase: characterization and effects of additives on activity.

    PubMed

    Lamikanra, O; Watson, M A

    2000-06-01

    Peroxidase in cantaloupe melon (Cucumis melo L. var. reticulatus Naud.), a fruit commonly fresh cut processed, was characterized to determine reaction pathway, optimal conditions for activity and effect of some additives on enzymatic action. Mn2+, CaCl2, NaNO2 and kinetin had partial inhibitory effects on enzyme activity. Activity was effectively inhibited by compounds capable of chelating peroxidase heme iron such as diethyldithiocarbamate and tiron, but unaffected by EDTA. Free radical scavenger, superoxide dismutase, also had no effect on reaction velocity. Enzymatic action was consistent with that of ascorbate peroxidase based on the relatively higher affinity for ascorbate over guaiacol. Optimum activity temperature was 50-55 degrees C. The enzyme was stable at temperatures below 40 degrees C and at 50 degrees C for up to 10 min. Over 90% of total activity was lost at 80 degrees C within 5 min. Broad pH optima, 5.5-7.5 at 50 degrees C and 6-7 at 30 degrees C, were obtained. Peroxidase activity in cantaloupe was higher than those in strawberry (Fragaria ananassa Duch.) and lettuce (Lactuca sativa L.), suggesting a relatively high oxidative stress in fresh cut cantaloupe. The potential use of ascorbate as an additive in fresh cut cantaloupe melon was demonstrated by its ability to preserve color in minimally processed fruits for 25 days at 4 degrees C, possibly as a result of an enhanced antioxidative action of the ascorbate-peroxidase complex and trace metal ion cofactors.

  16. Effects of acetylacetone additions on PZT thin film processing

    SciTech Connect

    Schwartz, R.W.; Assink, R.A.; Dimos, D.; Sinclair, M.B.; Boyle, T.J.; Buchheit, C.D.

    1995-02-01

    Sol-gel processing methods are frequently used for the fabrication of lead zirconate titanate (PZT) thin films for many electronic applications. Our standard approach for film fabrication utilizes lead acetate and acetic acid modified metal alkoxides of zirconium and titanium in the preparation of our precursor solutions. This report highlights some of our recent results on the effects of the addition of a second chelating ligand, acetylacetone, to this process. The authors discuss the changes in film drying behavior, densification and ceramic microstructure which accompany acetylacetone additions to the precursor solution and relate the observed variations in processing behavior to differences in chemical precursor structure induced by the acetylacetone ligand. Improvements in thin film microstructure, ferroelectric and optical properties are observed when acetylacetone is added to the precursor solution.

  17. Al addition effect of bulk MgB 2 superconductor

    NASA Astrophysics Data System (ADS)

    Shinohara, K.; Ikeda, H.; Yoshizaki, R.

    2007-10-01

    The properties of transport and magnetization have been investigated for bulk MgB2Alx superconductor with Al addition (x = 0, 0.5, 1 wt%). MgB2 bulk samples sintered at different temperatures at 650-740 °C were prepared in the undoped state. The temperature and applied field dependencies of resistivity and magnetization were measured for the samples. The sample sintered at 690 °C exhibited the highest critical current density (Jc) and the lowest resistivity. This undoped sample was chosen as a criterion sample, and the effect of Al addition on the MgB2 bulk was studied from the transport and magnetization properties in a magnetic field. For MgB2Alx bulk samples sintered at 690 °C, the resistivity increased and Jc decreased as amount of Al was increased.

  18. Effect of mixed additives on lead-acid battery electrolyte

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Arup; Basumallick, Indra Narayan

    This paper describes the corrosion behaviour of the positive and negative electrodes of a lead-acid battery in 5 M H 2SO 4 with binary additives such as mixtures of phosphoric acid and boric acid, phosphoric acid and tin sulphate, and phosphoric acid and picric acid. The effect of these additives is examined from the Tafel polarisation curves, double layer capacitance and percentage of inhibition efficiency. A lead salt battery has been fabricated replacing the binary mixture with an alternative electrolyte and the above electrochemical parameters have been evaluated for this lead salt battery. The results are explained in terms of H + ion transport and the morphological change of the PbSO 4 layer.

  19. Effect of rotational disruption on the size-frequency distribution of the Main Belt asteroid population

    NASA Astrophysics Data System (ADS)

    Jacobson, Seth A.; Marzari, Francesco; Rossi, Alessandro; Scheeres, Daniel J.; Davis, Donald R.

    2014-03-01

    The size distribution of small asteroids in the Main Belt is assumed to be determined by an equilibrium between the creation of new bodies out of the impact debris of larger asteroids and the destruction of small asteroids by collisions with smaller projectiles. However, for a diameter less than 6 km, we find that YORP-induced rotational disruption significantly contributes to the erosion even exceeding the effects of collisional fragmentation. Including this additional grinding mechanism in a collision evolution model for the asteroid belt, we generate size-frequency distributions from either an accretional or an `Asteroids were born big' initial size-frequency distribution that are consistent with observations reported in Gladman et al. Rotational disruption is a new mechanism that must be included in all future collisional evolution models of asteroids.

  20. Effects of aerodynamic interaction between main and tail rotors on helicopter hover performance and noise

    NASA Technical Reports Server (NTRS)

    Menger, R. P.; Wood, T. L.; Brieger, J. T.

    1983-01-01

    A model test was conducted to determine the effects of aerodynamic interaction between main rotor, tail rotor, and vertical fin on helicopter performance and noise in hover out of ground effect. The experimental data were obtained from hover tests performed with a .151 scale Model 222 main rotor, tail rotor and vertical fin. Of primary interest was the effect of location of the tail rotor with respect to the main rotor. Penalties on main rotor power due to interaction with the tail rotor ranged up to 3% depending upon tail rotor location and orientation. Penalties on tail rotor power due to fin blockage alone ranged up to 10% for pusher tail rotors and up to 50% for tractor tail rotors. The main rotor wake had only a second order effect on these tail rotor/fin interactions. Design charts are presented showing the penalties on main rotor power as a function of the relative location of the tail rotor.

  1. Cost Effectiveness of ASHRAE Standard 90.1-2013 for the State of Maine

    SciTech Connect

    Hart, Philip R.; Athalye, Rahul A.; Xie, YuLong; Zhuge, Jing Wei; Halverson, Mark A.; Loper, Susan A.; Rosenberg, Michael I.; Richman, Eric E.

    2015-12-01

    Moving to the ASHRAE Standard 90.1-2013 (ASHRAE 2013) edition from Standard 90.1-2010 (ASHRAE 2010) is cost-effective for the State of Maine. The table below shows the state-wide economic impact of upgrading to Standard 90.1-2013 in terms of the annual energy cost savings in dollars per square foot, additional construction cost per square foot required by the upgrade, and life-cycle cost (LCC) per square foot. These results are weighted averages for all building types in all climate zones in the state, based on weightings shown in Table 4. The methodology used for this analysis is consistent with the methodology used in the national cost-effectiveness analysis. Additional results and details on the methodology are presented in the following sections. The report provides analysis of two LCC scenarios: Scenario 1, representing publicly-owned buildings, considers initial costs, energy costs, maintenance costs, and replacement costs—without borrowing or taxes. Scenario 2, representing privately-owned buildings, adds borrowing costs and tax impacts.

  2. Synergistic anticancer effects of triptolide and celastrol, two main compounds from thunder god vine.

    PubMed

    Jiang, Qi-Wei; Cheng, Ke-Jun; Mei, Xiao-Long; Qiu, Jian-Ge; Zhang, Wen-Ji; Xue, You-Qiu; Qin, Wu-Ming; Yang, Yang; Zheng, Di-Wei; Chen, Yao; Wei, Meng-Ning; Zhang, Xu; Lv, Min; Chen, Mei-Wan; Wei, Xing; Shi, Zhi

    2015-10-20

    Triptolide and celastrol are two main active compounds isolated from Thunder God Vine with the potent anticancer activity. However, the anticancer effect of triptolide in combination with celastrol is still unknown. In the present study, we demonstrated that the combination of triptolide with celastrol synergistically induced cell growth inhibition, cell cycle arrest at G2/M phase and apoptosis with the increased intracellular ROS accumulation in cancer cells. Pretreatment with ROS scavenger N-acetyl-L-cysteine dramatically blocked the apoptosis induced by co-treatment with triptolide and celastrol. Treatment with celastrol alone led to the decreased expressions of HSP90 client proteins including survivin, AKT, EGFR, which was enhanced by the addition of triptolide. Additionally, the celastrol-induced expression of HSP70 and HSP27 was abrogated by triptolide. In the nude mice with xenograft tumors, the lower-dose combination of triptolide with celastrol significantly inhibited the growth of tumors without obvious toxicity. Overall, triptolide in combination with celastrol showed outstanding synergistic anticancer effect in vitro and in vivo, suggesting that this beneficial combination may offer a promising treatment option for cancer patients.

  3. Eddy damping effect of additional conductors in superconducting levitation systems

    NASA Astrophysics Data System (ADS)

    Jiang, Zhao-Fei; Gou, Xiao-Fan

    2015-12-01

    Passive superconducting levitation systems consisting of a high temperature superconductor (HTSC) and a permanent magnet (PM) have demonstrated several fascinating applications such as the maglev system, flywheel energy storage. Generally, for the HTSC-PM levitation system, the HTSC with higher critical current density Jc can obtain larger magnetic force to make the PM levitate over the HTSC (or suspended below the HTSC), however, the process of the vibration of the levitated PM, provides very limited inherent damping (essentially hysteresis). To improve the dynamic stability of the levitated PM, eddy damping of additional conductors can be considered as the most simple and effective approach. In this article, for the HTSC-PM levitation system with an additional copper damper attached to the HTSC, we numerically and comprehensively investigated the damping coefficient c, damping ratio, Joule heating of the copper damper, and the vibration frequency of the PM as well. Furthermore, we comparatively studied four different arrangements of the copper damper, on the comprehensive analyzed the damping effect, efficiency (defined by c/VCu, in which VCu is the volume of the damper) and Joule heating, and finally presented the most advisable arrangement.

  4. Effects of Particle Additives on Acoustically Coupled Fuel Droplet Combustion

    NASA Astrophysics Data System (ADS)

    Sim, Hyung Sub; Plascencia Quiroz, Miguel; Vargas, Andres; Bennewitz, John; Smith, Owen; Karagozian, Ann

    2016-11-01

    Addition of nanoscale particulates to liquid hydrocarbon fuels is suggested to have numerous benefits for combustion systems, although aggregation of metal nanoparticles can produce deleterious effects. The present experiments explore the effect of nano Aluminum (nAl) additives on the combustion of single liquid fuel droplets, with and without exposure of the droplets to standing acoustic waves. Building on prior studies, the present experiments quantify variations in the burning rate constant K for ethanol droplets with increasing concentrations of nAl in a quiescent environment. Burning fuel droplets that are continuously fed via a capillary as well as suspended (non-fed) droplets are examined. Nano Al is observed to create ejections of both particles and vapor toward the end of the burning period for non-fed droplets; this phenomenon is delayed when the droplet is replenished via continuous fuel delivery. Yet for the majority of conditions explored, increasing concentrations of nAl tend to reduce K. When ethanol droplets with nAl are exposed to standing waves, acoustic perturbations appear to delay particulate agglomeration, sustaining combustion for a longer period of time and increasing K. Supported by AFOSR Grant FA9550-15-1-0339.

  5. Probing the "additive effect" in the proline and proline hydroxamic acid catalyzed asymmetric addition of nitroalkanes to cyclic enones.

    PubMed

    Hanessian, Stephen; Govindan, Subramaniyan; Warrier, Jayakumar S

    2005-11-01

    The effect of chirality and steric bulk of 2,5-disubstituted piperazines as additives in the conjugate addition of 2-nitropropane to cyclohexenone, catalyzed by l-proline, was investigated. Neither chirality nor steric bulk affects the enantioselectivity of addition, which gives 86-93% ee in the presence of achiral and chiral nonracemic 2,5-disubstituted piperazines. Proline hydroxamic acid is shown for the first time to be an effective organocatalyst in the same Michael reaction.

  6. STELLAR DIAMETERS AND TEMPERATURES. III. MAIN-SEQUENCE A, F, G, AND K STARS: ADDITIONAL HIGH-PRECISION MEASUREMENTS AND EMPIRICAL RELATIONS

    SciTech Connect

    Boyajian, Tabetha S.; Jones, Jeremy; White, Russel; McAlister, Harold A.; Gies, Douglas; Von Braun, Kaspar; Van Belle, Gerard; Farrington, Chris; Schaefer, Gail; Ten Brummelaar, Theo A.; Sturmann, Laszlo; Sturmann, Judit; Turner, Nils H.; Goldfinger, P. J.; Vargas, Norm; Ridgway, Stephen

    2013-07-01

    Based on CHARA Array measurements, we present the angular diameters of 23 nearby, main-sequence stars, ranging from spectral types A7 to K0, 5 of which are exoplanet host stars. We derive linear radii, effective temperatures, and absolute luminosities of the stars using Hipparcos parallaxes and measured bolometric fluxes. The new data are combined with previously published values to create an Angular Diameter Anthology of measured angular diameters to main-sequence stars (luminosity classes V and IV). This compilation consists of 125 stars with diameter uncertainties of less than 5%, ranging in spectral types from A to M. The large quantity of empirical data is used to derive color-temperature relations to an assortment of color indices in the Johnson (BVR{sub J} I{sub J} JHK), Cousins (R{sub C} I{sub C}), Kron (R{sub K} I{sub K}), Sloan (griz), and WISE (W{sub 3} W{sub 4}) photometric systems. These relations have an average standard deviation of {approx}3% and are valid for stars with spectral types A0-M4. To derive even more accurate relations for Sun-like stars, we also determined these temperature relations omitting early-type stars (T{sub eff} > 6750 K) that may have biased luminosity estimates because of rapid rotation; for this subset the dispersion is only {approx}2.5%. We find effective temperatures in agreement within a couple of percent for the interferometrically characterized sample of main-sequence stars compared to those derived via the infrared flux method and spectroscopic analysis.

  7. Effects of Chlorophenoxy Herbicides and Their Main Transformation Products on DNA Damage and Acetylcholinesterase Activity

    PubMed Central

    Benfeito, Sofia; Silva, Tiago; Garrido, Jorge; Andrade, Paula B.; Sottomayor, M. J.; Borges, Fernanda; Garrido, E. Manuela

    2014-01-01

    Persistent pesticide transformation products (TPs) are increasingly being detected among different environmental compartments, including groundwater and surface water. However, there is no sufficient experimental data on their toxicological potential to assess the risk associated with TPs, even if their occurrence is known. In this study, the interaction of chlorophenoxy herbicides (MCPA, mecoprop, 2,4-D and dichlorprop) and their main transformation products with calf thymus DNA by UV-visible absorption spectroscopy has been assessed. Additionally, the toxicity of the chlorophenoxy herbicides and TPs was also assessed evaluating the inhibition of acetylcholinesterase activity. On the basis of the results found, it seems that AChE is not the main target of chlorophenoxy herbicides and their TPs. However, the results found showed that the transformation products displayed a higher inhibitory activity when compared with the parent herbicides. The results obtained in the DNA interaction studies showed, in general, a slight effect on the stability of the double helix. However, the data found for 4-chloro-2-methyl-6-nitrophenol suggest that this transformation product can interact with DNA through a noncovalent mode. PMID:24795892

  8. Thermal processing of EVA encapsulants and effects of formulation additives

    SciTech Connect

    Pern, F.J.; Glick, S.H.

    1996-05-01

    The authors investigated the in-situ processing temperatures and effects of various formulation additives on the formation of ultraviolet (UV) excitable chromophores, in the thermal lamination and curing of ethylene-vinyl acetate (EVA) encapsulants. A programmable, microprocessor-controlled, double-bag vacuum laminator was used to study two commercial as formulated EVA films, A9918P and 15295P, and solution-cast films of Elvaxrm (EVX) impregnated with various curing agents and antioxidants. The results show that the actual measured temperatures of EVA lagged significantly behind the programmed profiles for the heating elements and were affected by the total thermal mass loaded inside the laminator chamber. The antioxidant Naugard P{trademark}, used in the two commercial EVA formulations, greatly enhances the formation of UV-excitable, short chromophores upon curing, whereas other tested antioxidants show little effect. A new curing agent chosen specifically for the EVA formulation modification produces little or no effect on chromophore formation, no bubbling problems in the glass/EVX/glass laminates, and a gel content of {approximately}80% when cured at programmed 155{degrees}C for 4 min. Also demonstrated is the greater discoloring effect with higher concentrations of curing-generated chromophores.

  9. Adverse cognitive effects of antiepileptic pharmacotherapy: Each additional drug matters.

    PubMed

    Witt, Juri-Alexander; Elger, Christian E; Helmstaedter, Christoph

    2015-11-01

    The study was set up to evaluate the impact of the total drug load of antiepileptic pharmacotherapy on cognition. Retrospective analyses were based on 834 patients with epilepsy who underwent a brief routine assessment of executive function and verbal memory (EpiTrack Plus) at our department. The total drug load was quantified in two ways: (1) number of concurrent antiepileptic drugs (AEDs) and (2) total drug load according to the defined daily dose (DDD) provided by the World Health Organization. The cognitive measures showed higher inverse correlations with the number of AEDs (executive function: r=-0.35, p<0.001; memory: r=-0.22, p<0.001) than with the total DDD (executive function: r=-0.27, p<0.001; memory: r=-0.17, p<0.001). Reanalysis with statistical control for disease severity hardly changed the aforementioned results. With each additional drug in polytherapy, we observed a significantly lower performance in executive function. In this regard an additional explorative approach revealed that regimens combining AEDs with favorable cognitive profiles were associated with higher cognitive performance. Correlations between indicators of disease severity and drug load indices were low: altogether explaining only up to 9% of the observed variance in drug load. The findings demonstrate a considerable adverse effect of a higher drug load on cognition, especially on executive functions. Simply counting the number of drugs may be sufficient as a rough estimate of the risk of side effects. However, the combination of AEDs with favorable cognitive profiles may attenuate the negative effect of the total drug load.

  10. The effect of chemical additives on the synthesis of ethanol

    SciTech Connect

    Chuang, S.S.C.

    1989-04-30

    The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativeities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies of NO adsorption, reactive probing, steady state rate measurement, and transient kinetic study. CO insertion is known to be a key step to the formation of acetaldehyde and ethanol from CO hydrogenation. Reaction of ethylene with syngas is used as a probe to determine CO insertion capabilities of metal catalysts. During the sixth quarter of the project, the mechanism of CO insertion on Ni/SiO{sub 2} was investigated by in-situ infrared spectroscopy. Ni/SiO{sub 2}, a methanation catalyst, has been shown to exhibit CO insertion activity. In situ infrared studies of CO/H{sub 2} and C{sub 2}H{sub 4}/CO/H{sub 2} reactions show that the carbonylation of Ni/SiO{sub 2} to Ni(CO){sub 4} leads to an inhibition of methanation in CO hydrogenation but an enhancement of formation of propionaldehyde in C{sub 2}H{sub 4}/CO/H{sub 2} reaction. The results suggest that the sites for propionaldehyde formation is different from those for methanation.

  11. Hierarchical additive effects on heterosis in rice (Oryza sativa L.)

    PubMed Central

    Dan, Zhiwu; Hu, Jun; Zhou, Wei; Yao, Guoxin; Zhu, Renshan; Huang, Wenchao; Zhu, Yingguo

    2015-01-01

    Exploitation of heterosis in crops has contributed greatly to improvement in global food and energy production. In spite of the pervasive importance of heterosis, a complete understanding of its mechanisms has remained elusive. In this study, a small test-crossed rice population was constructed to investigate the formation mechanism of heterosis for 13 traits. The results of the relative mid-parent heterosis and modes of inheritance of all investigated traits demonstrated that additive effects were the foundation of heterosis for complex traits in a hierarchical structure, and multiplicative interactions among the component traits were the framework of heterosis in complex traits. Furthermore, new balances between unit traits and related component traits provided hybrids with the opportunity to achieve an optimal degree of heterosis for complex traits. This study dissected heterosis of both reproductive and vegetative traits from the perspective of hierarchical structure for the first time. Additive multiplicative interactions of component traits were proven to be the origin of heterosis in complex traits. Meanwhile, more attention should be paid to component traits, rather than complex traits, in the process of revealing the mechanism of heterosis. PMID:26442051

  12. Constant-Pressure Combustion Charts Including Effects of Diluent Addition

    NASA Technical Reports Server (NTRS)

    Turner, L Richard; Bogart, Donald

    1949-01-01

    Charts are presented for the calculation of (a) the final temperatures and the temperature changes involved in constant-pressure combustion processes of air and in products of combustion of air and hydrocarbon fuels, and (b) the quantity of hydrocarbon fuels required in order to attain a specified combustion temperature when water, alcohol, water-alcohol mixtures, liquid ammonia, liquid carbon dioxide, liquid nitrogen, liquid oxygen, or their mixtures are added to air as diluents or refrigerants. The ideal combustion process and combustion with incomplete heat release from the primary fuel and from combustible diluents are considered. The effect of preheating the mixture of air and diluents and the effect of an initial water-vapor content in the combustion air on the required fuel quantity are also included. The charts are applicable only to processes in which the final mixture is leaner than stoichiometric and at temperatures where dissociation is unimportant. A chart is also included to permit the calculation of the stoichiometric ratio of hydrocarbon fuel to air with diluent addition. The use of the charts is illustrated by numerical examples.

  13. Ivermectin plus diethylcarbamazine: an additive effect on early microfilarial clearance.

    PubMed

    Moulia-Pelat, J P; Nguyen, L N; Glaziou, P; Chanteau, S; Ottesen, E A; Cardines, R; Martin, P M; Cartel, J L

    1994-02-01

    The effects of ivermectin, diethylcarbamazine (DEC), and the combination of both drugs on levels of microfilaremia (mf) were studied in 30 male Polynesian Wuchereria bancrofti carriers. Microfilarial densities were measured 30 min (H1/2), 1 hr (H1), and 2, 4, 8, 24, and 96 hr (H2, H4, H8, H24, and H96) after supervised single doses of ivermectin plus DEC (400 micrograms/kg plus 1 mg/kg, respectively, 400 micrograms/kg plus 3 mg/kg, respectively, and 400 micrograms/kg plus 6 mg/kg, respectively), DEC (6 mg/kg) alone, and ivermectin (400 micrograms/kg and 100 micrograms/kg, respectively) alone given to six groups of five patients each. The results showed that 1) DEC alone or combined with ivermectin induced a rapid clearance of mf after drug intake; at H1/2, the number of circulating microfilariae was reduced to 16%, 8%, 28%, and 31%, respectively, of pretreatment values in the groups receiving ivermectin plus DEC (400 micrograms/kg plus 1 mg/kg, 400 micrograms/kg plus 3 mg/kg, and 400 micrograms/kg plus 6 mg/kg) and DEC (6 mg/kg) alone; 2) ivermectin alone induced a rapid increase of mf densities during the first 2 hr, followed by a sharp decrease from H4 to H96; and 3) between H8 and H96, mf clearance was almost complete with the combination of ivermectin and DEC. A comparison among groups did not show any synergistic interaction between ivermectin and DEC on the clearance of microfilaria, with the effect of each drug being additive to each another.

  14. Effect of surfactant addition on phenanthrene biodegradation in sediments

    SciTech Connect

    Tsomides, H.J.; Hughes, J.B.; Thomas, J.M.; Ward, C.H.

    1995-12-31

    A laboratory study was conducted to determine whether commercial surfactants enhance the bioremediation of PAH-contaminated sediments. Phenanthrene was chosen as a representative PAH. An inoculum of PAH-degrading microorganisms, enriched from an aquatic sediment, was used in sediment-water slurry microcosm biodegradation experiments. Of seven nonionic surfactants tested, only one (Triton X-100) did not inhibit phenanthrene mineralization at concentrations above the critical micelle concentration (CMC). Temporal studies on Triton X-100 revealed that while it initially inhibited mineralization in sediment-free microcosms, after 1 week Triton X-100 slightly improved phenanthrene biotransformation and mineralization in microcosms with and without sediment. For all treatments, phenanthrene disappearance was complete after 9 d. and mineralization reached 50 to 65% after 12 d. Sorption to the sediment appears to have reduced the free aqueous surfactant concentration, thereby reducing surfactant toxicity to the microorganisms. These results suggest that many surfactants are toxic to PAH-degrading microorganisms, and while surfactant addition may not always have adverse effects on biodegradation, the use of surfactants might not be necessary to achieve complete contaminant removal.

  15. Effect of surfactant addition on phenanthrene biodegradation in sediments

    SciTech Connect

    Tsomides, H.J.; Hughes, J.B.; Thomas, J.M.; Ward, C.H.

    1995-06-01

    A laboratory study was conducted to determine whether commercial surfactants enhance the bioremediation of PAH-contaminated sediments. Phenanthrene was chosen as a representative PAH; an inoculum of PAH-degrading microorganisms, enriched from an aquatic sediment, was used in sediment-water slurry microcosm biodegradation experiments. Of seven non-ionic surfactants tested, only one (Triton X-100) did not inhibit phenanthrene mineralization at concentrations above the critical micelle concentration (CMC). Temporal studies on Triton X-100 revealed that while it initially inhibited mineralization in sediment-free microcosms, after 1 week Triton X-100 slightly improved phenanthrene biotransformation and mineralization in microcosms with and without sediment. For all treatments, phenanthrene disappearance was complete after 9 d, and mineralization reached 50 to 65% after 12 d. Sorption to the sediment appears to have reduced the free aqueous surfactant concentration, thereby reducing surfactant toxicity to the microorganisms. These results suggest that many surfactants are toxic to PAH-degrading microorganisms, and while surfactant addition may not always have adverse effects on biodegradation, the use of surfactants might not be desirable to achieve complete contamination removal.

  16. Congruence of additive and non-additive effects on gene expression estimated from pedigree and SNP data.

    PubMed

    Powell, Joseph E; Henders, Anjali K; McRae, Allan F; Kim, Jinhee; Hemani, Gibran; Martin, Nicholas G; Dermitzakis, Emmanouil T; Gibson, Greg; Montgomery, Grant W; Visscher, Peter M

    2013-05-01

    There is increasing evidence that heritable variation in gene expression underlies genetic variation in susceptibility to disease. Therefore, a comprehensive understanding of the similarity between relatives for transcript variation is warranted--in particular, dissection of phenotypic variation into additive and non-additive genetic factors and shared environmental effects. We conducted a gene expression study in blood samples of 862 individuals from 312 nuclear families containing MZ or DZ twin pairs using both pedigree and genotype information. From a pedigree analysis we show that the vast majority of genetic variation across 17,994 probes is additive, although non-additive genetic variation is identified for 960 transcripts. For 180 of the 960 transcripts with non-additive genetic variation, we identify expression quantitative trait loci (eQTL) with dominance effects in a sample of 339 unrelated individuals and replicate 31% of these associations in an independent sample of 139 unrelated individuals. Over-dominance was detected and replicated for a trans association between rs12313805 and ETV6, located 4MB apart on chromosome 12. Surprisingly, only 17 probes exhibit significant levels of common environmental effects, suggesting that environmental and lifestyle factors common to a family do not affect expression variation for most transcripts, at least those measured in blood. Consistent with the genetic architecture of common diseases, gene expression is predominantly additive, but a minority of transcripts display non-additive effects.

  17. Lubricant and additive effects on spur gear fatigue life

    NASA Technical Reports Server (NTRS)

    Townsend, D. P.; Zaretsky, E. V.; Scibbe, H. W.

    1985-01-01

    Spur gear endurance tests were conducted with six lubricants using a single lot of consumable-electrode vacuum melted (CVM) AISI 9310 spur gears. The sixth lubricant was divided into four batches each of which had a different additive content. Lubricants tested with a phosphorus-type load carrying additive showed a statistically significant improvement in life over lubricants without this type of additive. The presence of sulfur type antiwear additives in the lubricant did not appear to affect the surface fatigue life of the gears. No statistical difference in life was produced with those lubricants of different base stocks but with similar viscosity, pressure-viscosity coefficients and antiwear additives. Gears tested with a 0.1 wt % sulfur and 0.1 wt % phosphorus EP additives in the lubricant had reactive films that were 200 to 400 (0.8 to 1.6 microns) thick.

  18. Relative effectiveness of additive pain interventions during vaccination in infants

    PubMed Central

    Taddio, Anna; Riddell, Rebecca Pillai; Ipp, Moshe; Moss, Steven; Baker, Stephen; Tolkin, Jonathan; Malini, Dave; Feerasta, Sharmeen; Govan, Preeya; Fletcher, Emma; Wong, Horace; McNair, Caitlin; Mithal, Priyanjali; Stephens, Derek

    2017-01-01

    BACKGROUND: Vaccine injections can cause acute pain and distress in infants, which can contribute to dissatisfaction with the vaccination experience and vaccine hesitancy. We sought to compare the effectiveness of additive pain interventions administered consistently during vaccine injections in the first year of life. METHODS: We conducted a multicentre, longitudinal, double-blind, add-on, randomized controlled trial. Healthy infants were randomly assigned to 1 of 4 levels of pain management for all vaccine injections at 2, 4, 6 and 12 months: (i) placebo control; (ii) parent-directed video education about infant soothing; (iii) the video plus sucrose administered orally or (iv) the video plus sucrose plus liposomal lidocaine applied topically. All infants benefit from injection techniques that minimize pain. We used a double-dummy design; hence all parents watched a video (active psychological intervention or placebo) and all infants received oral solution (sucrose or placebo) and topical cream (lidocaine or placebo). We assessed infant distress during 3 phases — preinjection (baseline), vaccine injection (needle), and 1 minute postinjection (recovery) — using the Modified Behavioural Pain Scale (range 0–10). We compared scores between groups and across infant ages using a mixed-model repeated-measures analysis. RESULTS: A total of 352 infants participated in the study, from Jan. 17, 2012, to Feb. 2, 2016. Demographics did not differ among intervention groups (p > 0.05). Baseline pain scores did not differ among intervention groups (p = 0.4), but did differ across ages (p < 0.001). Needle pain scores differed among groups (p = 0.003) and across ages (p < 0.001). The mean (± standard deviation) needle score was 6.3 (± 0.8) in the video–sucrose–lidocaine group compared with 6.7 (± 0.8) in each of the other groups. There were no other between-group differences. Recovery scores did not differ among groups (p = 0.98), but did differ across ages (p < 0

  19. Chemistry of Food Additives: Direct and Indirect Effects.

    ERIC Educational Resources Information Center

    Pauli, George H.

    1984-01-01

    The primary component(s), impurities, and degradation products of polysorbate 80, nitrate and nitrite salts, and diethylpyrocarbonate (DEPC) are discussed. Safety considerations related to these food additives are also noted. The chick-edema factor which results from an additive in poultry feed is also discussed. (JN)

  20. Effect of a phytogenic feed additive on the susceptibility of Onchorhynchus mykiss to Aeromonas salmonicida.

    PubMed

    Menanteau-Ledouble, S; Krauss, I; Santos, G; Fibi, S; Weber, B; El-Matbouli, M

    2015-06-29

    In recent years, feed additives have increasingly been adopted by the aquaculture industry. These supplements not only offer an alternative to antibiotics but have also been linked to enhanced growth performance. However, the literature is still limited and provides contradictory information on their effectiveness. This is mainly due to the wide variety of available products and their complex mechanisms of action. Phytogenic feed additives have been shown to have antimicrobial effects and can improve growth performance. In the present study, we investigated the susceptibility of several fish pathogenic bacteria to a phytogenic essential oil product in vitro. In addition, we determined the protective effect of a commercial phytogenic feed additive containing oregano, anis and citrus oils on the resistance of rainbow trout Oncorhynchus mykiss to infection by Aeromonas salmonicida. The bacterium was administered through 3 different routes: intra-peritoneal injection, immersion in a bacterial solution and cohabitation with infected fish. Mortality rates were significantly lower in infected rainbow trout that had received the feed additive: the overall mortality rate across all routes of infection was 18% in fish fed a diet containing the additive compared to 37% in fish that received unsupplemented feed. The route of infection also significantly impacted mortality, with average mortality rates of 60, 17.5 and 5% for intra-peritoneal injection, immersion and cohabitation, respectively. In general, fish were better protected against infection by immersion than infection by injection.

  1. Relativistic Effects and the Chemistry of the Heaviest Main-Group Elements

    ERIC Educational Resources Information Center

    Thayer, John S.

    2005-01-01

    The chemical properties of the heaviest main-group elements often show features not found in their lighter counterparts while relativistic effects play an important role in the chemistry of these elements. The unusual properties and their relation to relativistic effects with emphasis on the new research are emphasized.

  2. Concentration Addition, Independent Action and Generalized Concentration Addition Models for Mixture Effect Prediction of Sex Hormone Synthesis In Vitro

    PubMed Central

    Hadrup, Niels; Taxvig, Camilla; Pedersen, Mikael; Nellemann, Christine; Hass, Ulla; Vinggaard, Anne Marie

    2013-01-01

    Humans are concomitantly exposed to numerous chemicals. An infinite number of combinations and doses thereof can be imagined. For toxicological risk assessment the mathematical prediction of mixture effects, using knowledge on single chemicals, is therefore desirable. We investigated pros and cons of the concentration addition (CA), independent action (IA) and generalized concentration addition (GCA) models. First we measured effects of single chemicals and mixtures thereof on steroid synthesis in H295R cells. Then single chemical data were applied to the models; predictions of mixture effects were calculated and compared to the experimental mixture data. Mixture 1 contained environmental chemicals adjusted in ratio according to human exposure levels. Mixture 2 was a potency adjusted mixture containing five pesticides. Prediction of testosterone effects coincided with the experimental Mixture 1 data. In contrast, antagonism was observed for effects of Mixture 2 on this hormone. The mixtures contained chemicals exerting only limited maximal effects. This hampered prediction by the CA and IA models, whereas the GCA model could be used to predict a full dose response curve. Regarding effects on progesterone and estradiol, some chemicals were having stimulatory effects whereas others had inhibitory effects. The three models were not applicable in this situation and no predictions could be performed. Finally, the expected contributions of single chemicals to the mixture effects were calculated. Prochloraz was the predominant but not sole driver of the mixtures, suggesting that one chemical alone was not responsible for the mixture effects. In conclusion, the GCA model seemed to be superior to the CA and IA models for the prediction of testosterone effects. A situation with chemicals exerting opposing effects, for which the models could not be applied, was identified. In addition, the data indicate that in non-potency adjusted mixtures the effects cannot always be

  3. Main Effects of Diagnoses, Brain Regions, and their Interaction Effects for Cerebral Metabolites in Bipolar and Unipolar Depressive Disorders

    PubMed Central

    Tan, Hai-Zhu; Li, Hui; Liu, Chen-Feng; Guan, Ji-Tian; Guo, Xiao-Bo; Wen, Can-Hong; Ou, Shao-Min; Zhang, Yin-Nan; Zhang, Jie; Xu, Chong-Tao; Shen, Zhi-Wei; Wu, Ren-Hua; Wang, Xue-Qin

    2016-01-01

    Previous studies suggested patients with bipolar depressive disorder (BDd) or unipolar depressive disorder (UDd) have cerebral metabolites abnormalities. These abnormalities may stem from multiple sub-regions of gray matter in brain regions. Thirteen BDd patients, 20 UDd patients and 20 healthy controls (HC) were enrolled to investigate these abnormalities. Absolute concentrations of 5 cerebral metabolites (glutamate-glutamine (Glx), N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), creatine (Cr), parietal cortex (PC)) were measured from 4 subregions (the medial frontal cortex (mPFC), anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and parietal cortex (PC)) of gray matter. Main and interaction effects of cerebral metabolites across subregions of gray matter were evaluated. For example, the Glx was significantly higher in BDd compared with UDd, and so on. As the interaction analyses showed, some interaction effects existed. The concentrations of BDds’ Glx, Cho, Cr in the ACC and HCs’ mI and Cr in the PC were higher than that of other interaction effects. In addition, the concentrations of BDds’ Glx and Cr in the PC and HCs’ mI in the ACC were statistically significant lower than that of other interaction effects. These findings point to region-related abnormalities of cerebral metabolites across subjects with BDd and UDd. PMID:27869127

  4. Main Effects of Diagnoses, Brain Regions, and their Interaction Effects for Cerebral Metabolites in Bipolar and Unipolar Depressive Disorders

    NASA Astrophysics Data System (ADS)

    Tan, Hai-Zhu; Li, Hui; Liu, Chen-Feng; Guan, Ji-Tian; Guo, Xiao-Bo; Wen, Can-Hong; Ou, Shao-Min; Zhang, Yin-Nan; Zhang, Jie; Xu, Chong-Tao; Shen, Zhi-Wei; Wu, Ren-Hua; Wang, Xue-Qin

    2016-11-01

    Previous studies suggested patients with bipolar depressive disorder (BDd) or unipolar depressive disorder (UDd) have cerebral metabolites abnormalities. These abnormalities may stem from multiple sub-regions of gray matter in brain regions. Thirteen BDd patients, 20 UDd patients and 20 healthy controls (HC) were enrolled to investigate these abnormalities. Absolute concentrations of 5 cerebral metabolites (glutamate-glutamine (Glx), N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), creatine (Cr), parietal cortex (PC)) were measured from 4 subregions (the medial frontal cortex (mPFC), anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), and parietal cortex (PC)) of gray matter. Main and interaction effects of cerebral metabolites across subregions of gray matter were evaluated. For example, the Glx was significantly higher in BDd compared with UDd, and so on. As the interaction analyses showed, some interaction effects existed. The concentrations of BDds’ Glx, Cho, Cr in the ACC and HCs’ mI and Cr in the PC were higher than that of other interaction effects. In addition, the concentrations of BDds’ Glx and Cr in the PC and HCs’ mI in the ACC were statistically significant lower than that of other interaction effects. These findings point to region-related abnormalities of cerebral metabolites across subjects with BDd and UDd.

  5. Effects of Video Games as Reinforcers for Computerized Addition Performance.

    ERIC Educational Resources Information Center

    Axelrod, Saul; And Others

    1987-01-01

    Four 2nd-grade students completed addition problems on a computer, using video games as reinforcers. Two variable ratio schedules of reinforcement failed to increase student accuracy or the rate of correct responses. In a no-games reinforcement condition, students had more opportunities to respond and had a greater number of correct answers.…

  6. Biodegradability testing of synthetic ester lubricants--effects of additives and usage.

    PubMed

    Eisentraeger, Adolf; Schmidt, Martin; Murrenhoff, Hubertus; Dott, Wolfgang; Hahn, Stefan

    2002-07-01

    The optimised biodegradability test system "O2/CO2 Headspace Test with GC-TCD" is used for the assessment of synthetic ester lubricants. The effects of both additives and usage on biodegradability are examined and discussed. Ester based cutting fluids and hydraulic fluids with and without additives are used under defined conditions at machine tools and hydraulic and plain bearing test benches. The lubricants are characterised additionally with respect to kinematic viscosity, acidity and elemental composition. Furthermore, a formulated mineral oil is characterised before and after usage at an hydraulic test bench. The results clearly show that the mineral oil is far less biodegradable than the ester oils and that their biodegradability is not affected by usage. Biodegradability of the ester oils is mainly depending on the characteristics of the base fluids and not affected by the additives. Antioxidants are influencing stability respectively biodegradability indirectly, since they prevent oxopolymerisation effects. Other effects of usage on biodegradation are not detected. In this context, the antioxidants ensure ready biodegradability and have a positive effect on the environmental fate of synthetic ester lubricants.

  7. Main and interactive effects of multiple global-change factors on soil respiration and its components: a meta-analysis

    NASA Astrophysics Data System (ADS)

    Zhou, Xuhui

    2014-05-01

    Global change usually involves simultaneous changes in multiple environmental factors, which may considerably affect ecosystem structure and functioning and alter ecosystem services to human society. With increased awareness of their potential interactions, some multi-factorial studies have been conducted to investigate their main and interactive effects on carbon (C) cycling in terrestrial ecosystem. However, how multiple global-change factors affected soil respiration (Rs) and its components (i.e., autotrophic (Ra) and heterotrophic respiration (Rh)) remains controversial among individual studies. In this study, we conducted a meta-analysis to examine the main and possible 2- or 3-factor interactive effects with warming (W), elevated CO2 (E), nitrogen addition (N), increased precipitation (I) and drought (D) on Rs and its components from 150 published papers. Our results show that E, W, I and N significantly stimulated Rs by 29.23%, 7.19%, 22.95%, and 16.90% (p<0.05), respectively, while I depressed it by 16.90% (p<0.01). E consistently induced a significant positive effect on both Ra and Rh, while I affected them with an opposite trend. Among nine two-way interactive effects on Rs, synergistic interaction (i.e., the effect of combined treatment > the additive effects of single two main factors) occurred in E×N, E×W, I×N, and D×W, while neutral interaction (i.e., the effect of combined treatment ≡ the additive one) and antagonistic interaction (i.e., the effect of combined treatment < the additive one)was rare, only in I×W for neutral one and in N×W and I×E for the latter. In addition, E×W and E×N displayed synergistic interactions on Rh. The more dominance of synergistic interactions in two-way interactive effects on Rs and Rh may determine a central positive tendency of Rs in future, and affect the feedback of terrestrial C cycle to the climate system correspondingly.

  8. Effects of managed mental health care on service use in urban and rural Maine.

    PubMed

    Hartley, D

    2001-01-01

    This study takes advantage of a "natural experiment" resulting from the reassignment of all Maine state employees to a managed behavioral health plan in December 1992. By comparing mental health claims before and after that date, the effects of a behavioral health carve-out on mental health utilization by rural and urban beneficiaries were investigated. Following the implementation of the carve-out, the penetration rate, defined as the proportion of beneficiaries who sought help for an affective disorder, increased significantly in both rural and urban areas (P < 0.001). However, the rural penetration rate remained significantly lower than the urban rate (before implementation, 25.8 vs. 52.2 users per 1,000 enrollees, P < 0.001; after implementation, 57.8 vs. 85.8 users per 1,000 enrollees, P < 0.001). Similarly, rural utilization rates, defined as the average number of outpatient mental health visits per user, were significantly lower than urban rates both before and after implementation of the carve-out (before, 9.2 us. 12.9 visits per user, P < 0.001; after, 9.8 vs. 13.3 visits per user, P < 0.001). Before-after differences were not significant. In addition, the proportion of mental health care provided in the primary care setting increased after implementation of the carve-out (from 9.5 percent of all visits before to 12.6 percent of all visits after, P < 0.001). The increase in penetration rates can be attributed, in part, to a member education initiative undertaken during the transition from fee-for-service to managed care. This type of carve-out arrangement does not threaten to reduce access to mental health services, provided the managed behavioral health organization (MBHO) managing the carve-out is willing to accept primary care practitioners as part of its provider network.

  9. Effects of chronic ammonium sulfate treatment on the forest at the Bear Brook Watershed in Maine.

    PubMed

    Elvir, Jose Alexander; Wiersma, G Bruce; Bethers, Suzanne; Kenlan, Peter

    2010-12-01

    At the Bear Brook Watershed in Maine (BBWM), the forest tree composition was characterized and the effects of the chronic ammonium sulfate ((NH(4))(2)SO(4)) treatment on basal area growth, foliar chemistry, and gas exchange were investigated on forest species. The BBWM is a paired watershed forest ecosystem study with one watershed, West Bear (WB), treated since 1989 with 26.6 kg N ha(-1) year(-1) and 30 kg S ha(-1) year(-1)applied bimonthly as (NH(4))(2)SO(4), while the other watershed, East Bear (EB), serves as a reference. Tree species richness, density, and mortality were found to be similar between watersheds. Basal area increment was estimated from red spruce and sugar maple, showing that, for the first 7 years of treatment, it was significantly higher for sugar maple growing in WB compared to EB, but no differences were observed for red spruce between watersheds. However, the initial higher sugar maple basal area growth in WB subsequently decreased after 8 years of treatment. Foliar chemical analysis performed in trees, saplings, and ground flora showed higher N concentrations in the treated WB compared to the reference EB. But, foliar cation concentrations, especially Ca and Mg, were significantly lower for most of the species growing in WB compared with those growing in EB. For sugar maple, foliar N was higher on WB, but there were no differences in foliar Ca and Mg concentrations between treated and reference watersheds. In addition, only sugar maple trees in the treated WB showed significantly higher photosynthetic rates compared to reference EB trees.

  10. Age and work environment characteristics in relation to sleep: Additive, interactive and curvilinear effects.

    PubMed

    Parkes, Katharine R

    2016-05-01

    Although additive combinations of age and work environment characteristics have been found to predict sleep impairment, possible age x work environment interactions have been largely disregarded. The present study examined linear and curvilinear interactions of age with work environment measures in relation to sleep quality and duration. Survey data were collected from offshore day-shift personnel (N = 901). Main effects and interactions of the age terms with work environment measures (job demand, control, and social support, physical environment and strenuous work) were evaluated. Sleep duration was predicted by a curvilinear interaction, age(2) x job demand (p < .005), and by the age x social support interaction (p < .002); sleep quality was predicted by age x job demand (p < .002). Job control and physical environment showed significant additive effects. At a time when older employees are encouraged to remain in the workforce, the findings serve to increase understanding of how ageing and work demands jointly contribute to sleep impairment.

  11. The effect of feedstock additives on FCC catalyst deactivation

    SciTech Connect

    Hughes, R.; Koon, C.L.; McGhee, B.

    1995-12-31

    Fluid catalytic cracking is a major petroleum refining process and because of this the deactivation of FCC catalysts by coke deposition has been the subject of considerable investigation during the past 50 years. Nevertheless, a lack of understanding of the fundamental understanding of processes leading to coke formation still exists. Basic studies using Zeolites have usually involved excessively high levels of coke deposits compared to normal FCC operation. The present study addresses coke formation at realistic levels of 0.5 to 1.0% w/w using a standard MAT reactor in which concentrations of 1% and 10% of various additives were added to the n-hexadecane feedstock. These additives included, quinoline, phenanthrene, benzofuran, thianaphthene and indene. The coke formed was characterised by mass spectrometry and was significantly aliphatic in nature, the amount formed increasing in the order quinoline, phenanthrene, thianaphthene, benzofuran, indene. Quinoline acts primarily as a poison, whereas the other additives tend to promote coke formation in n-hexadecane cracking.

  12. Effect of shaddock albedo addition on the properties of frankfurters.

    PubMed

    Shan, Bing; Li, Xingmin; Pan, Teng; Zheng, Limin; Zhang, Hao; Guo, Huiyuan; Jiang, Lu; Zhen, Shaobo; Ren, Fazheng

    2015-07-01

    To explore the potential as a natural auxiliary emulsifier, shaddock albedo was added into frankfurters at six different levels: 0.0, 2.5, 5.0, 7.5, 10 and 12.5 %. The emulsion capacity (EC) of meat batters and cooking properties of frankfurters were evaluated. EC of meat batters was improved with the addition of shaddock albedo and the maximum value was reached at the 5 % albedo concentration. The addition of shaddock albedo resulted in lower cooking losses of frankfurters, with the lowest value obtained at the 7.5 % level. The presence of shaddock albedo decreased the total expressible fluid (TEF) and the proportion of fat in total expressible fluid (PF) which indicated the emulsion stability of frankfurters and the lowest values both occurred at the concentration of 7.5 %. Shaddock albedo inclusion increased the lightness and yellowness of frankfurters and decreased redness. Texture profile analysis showed increased hardness and decreased chewiness of frankfurters with the addition of shaddock albedo. Consequently, shaddock albedo could be a potential source of auxiliary emulsifier filler for emulsion-type meat products.

  13. The Effect of Tungsten Additions on Disk Alloy CH98

    NASA Technical Reports Server (NTRS)

    Gayda, John; Gabb, Timothy P.

    2003-01-01

    Gas turbine engines for future subsonic transports will probably have higher pressure ratios which will require nickelbase superalloy disks with 1300 to 1400 F temperature capability. Several advanced disk alloys are being developed to fill this need. One of these, CH98, is a promising candidate for gas turbine engines and is being studied in NASA s Advanced Subsonic Technology (AST) program. For large disks, residual stresses generated during quenching from solution heat treatments are often reduced by a stabilization heat treatment, in which the disk is heated in the range of 1500 to 1600 F for several hours followed by a static air cool and age. The reduction in residual stress levels lessens distortion during machining of disks. Previous work on CH98 has indicated that stabilization treatments will decrease creep capability, however, tungsten additions appear to improve the creep capability of stabilized and aged CH98. In this study, a systematic variation of tungsten additions to CH98 was investigated. Specifically, the 1300 F tensile, creep, and fatigue crack growth properties of stabilized CH 98 were assessed with varying levels of tungsten additions.

  14. The Effect of Fluorocarbon Surfactant Additives on the Effective Viscosity of Acetone Solutions of Cellulose Diacetate,

    DTIC Science & Technology

    2014-09-26

    34 FOREIGN TECHNOLOGY DIVISION i00 Lfl .. THE EFFECT OF FLUOROCARBON SURFACTANT ADDITIVES ON THE EFFECTIVE VISCOSITY OF ACETONE SOLUTIONS OF CELLULOSE...ADDITIVES ON TH~ .. t- ’_ ition EFFECTIVE VISCOSITY OF ACETONE SOLUTIONS OF CELLULOSE DIACETATE D~rbt~l By: L.A. Shits, N. Yu. Kal’nova Codesuton English...VISCOSITY OF ACETONE SOLUTIONS OF CELLULOSE DIACETATE L. A. Shits, N. Yu. Kal’nova (Institute of Physical Chemistry of the AS USSR, Moscow) ! - The

  15. Ordinary Social Interaction and the Main Effect Between Perceived Support and Affect.

    PubMed

    Lakey, Brian; Vander Molen, Randy J; Fles, Elizabeth; Andrews, Justin

    2016-10-01

    Relational regulation theory hypothesizes that (a) the main effect between perceived support and mental health primarily reflects ordinary social interaction rather than conversations about stress and how to cope with it, and (b) the extent to which a provider regulates a recipient's mental health primarily reflects the recipient's personal taste (i.e., is relational), rather than the provider's objective supportiveness. In three round-robin studies, participants rated each other on supportiveness and the quality of ordinary social interaction, as well as their own affect when interacting with each other. Samples included marines about to deploy to Afghanistan (N = 100; 150 dyads), students sharing apartments (N = 64; 96 dyads), and strangers (N = 48; 72 dyads). Perceived support and ordinary social interaction were primarily relational, and most of perceived support's main effect on positive affect was redundant with ordinary social interaction. The main effect between perceived support and affect emerged among strangers after brief text conversations, and these links were partially verified by independent observers. Findings for negative affect were less consistent with theory. Ordinary social interaction appears to be able to explain much of the main effect between perceived support and positive affect.

  16. Effects of Direct Instruction and Metacomprehension Training on Finding Main Ideas.

    ERIC Educational Resources Information Center

    Graves, Anne W.

    1986-01-01

    Twenty-four learning disabled children (grades 5-8) with adequate decoding skills, but who demonstrated problems in reading comprehension, received training in finding the main idea. Among several findings was that metacomprehension (self-monitoring) plus direct instruction was more effective than direct instruction alone. (Author/JW)

  17. Effects of an additional dimension in the Young experiment

    SciTech Connect

    Barros, Allan Kardec

    2015-09-15

    The results of the Young experiment can be analyzed either by classical or Quantum Physics. The later one though leads to a more complete interpretation, based on two different patterns that appear when one works either with single or double slits. Here we show that the two patterns can be derived from a single principle, in the context of General Relativity, if one assumes an additional spatial dimension to the four known today. The found equations yield the same results as those in Quantum Mechanics.

  18. Effects of Fuel Specification and Additives on Soot Formation.

    DTIC Science & Technology

    1983-12-01

    develop models destined for gas turbine design. Present knowledge of these effects is limited to systems which are either too simple to adequately...information essential. To answer these technical questions, a multifaceted study was undertaken to 0) test candidate model laboratory combustors in the...effectiveness of the ASTM smoke point in predict- ing sooting behavior in complex flows. Two candidate model laboratory combustors were used -- a swirl

  19. Roll Forming of AHSS: Numerical Simulation and Investigation of Effects of Main Process Parameters on Quality

    NASA Astrophysics Data System (ADS)

    Salonitis, Konstantinos; Paralikas, John; Chryssolouris, George

    The roll forming process is one of the main processes of producing straight profiles in many industrial sectors. The introduction of Advanced High Strength Steels (AHSS), such as the DP and TRIP-series, into the production of roll-formed profiles has emerged new challenges. The combination of a higher yield strength with a lower total elongation of AHSS, brings new challenges to the roll forming process. In the current study, the numerical simulation of a V-section profile has been implemented. The effect of the main process parameters, such as the roll forming line velocity, rolls inter-distance, roll gap and rolls diameter on quality characteristics is investigated.

  20. Dose effect in the wood plastic composite formation in the presence of additives and co-additives

    NASA Astrophysics Data System (ADS)

    Khan, Mubarak A.; Ali, K. M. Idriss

    1994-10-01

    Wood plastic composite (WPC) formation was studied with simul wood and butylmethacrylate (BMA) at different compositions with swelling solvent methanol in the presence of a set of multifunctional acrylate monomer additives like N-vinyl Pyrrolidone (NVP), tripropylene glycol diacrylate (TPGDA) and trimethylol propane triacrylate (TMPTA) at a different doses between 1 and 3 Mrad using Co 60 gamma source. This was further investigated using another set of additives chosen from oligomers such as epoxy acrylate (EA), urethane acrylate (UA) and polyester acrylate (PEA). TMPTA yielded the highest polymer loading at relatively low dose (2 Mrad). Effect of co-additives like sulfuric acid (H + ions), copper sulphate (Cu 2+ ions) and urea was investigated in these series. Tensile strength (TS) of the composites were determined and the highest TS values were obtained with the composite produced in presence of urea.

  1. Effects of NaOH addition on performance of the direct hydrazine fuel cell

    NASA Astrophysics Data System (ADS)

    Yin, Wen Xia; Li, Zhou Peng; Zhu, Jing Ke; Qin, Hai Ying

    In this work, we suggested a figuration of the direct hydrazine fuel cell (DHFC) using non-precious metals as the anode catalyst, ion exchange membranes as the electrolyte and alkaline hydrazine solutions as the fuel. NaOH addition in the anolyte effectively improved the open circuit voltage and the performance of the DHFC. A power density of 84 mW cm -2 has been achieved when operating the cell at room temperature. It was found that the cell performance was mainly influenced by anode polarization when using alkaline N 2H 4 solutions with low NaOH concentrations. However, when using alkaline N 2H 4 solutions with high NaOH concentrations as the fuel, the cell performance was mainly influenced by cathode polarization.

  2. Additive thermochemical effects in turbulent erosive boundary layers

    SciTech Connect

    Buckingham, A.C.; Levatin, J.L.

    1983-01-18

    Previously obtained interior ballistics and wall boundary layer modeling results indicate that significant reduction in erosive heating can be expected when finely divided particles are dispersed through the propellant combustion flow field. Attention was first placed on the particle size influences, together with particle dispersal dynamics in both turbulent combustion core flow and the erosive wall boundary layer region. Submicron thermochemically inert particles were predicted to disperse readily to the near wall region where they were then entrained in the boundary layer. This was estimated to substantially reduce the predicted erosive heat and mass transfer and experimentally confirmed. Examination of the time-averaged turbulent boundary layer macrostructure changes indicated that inertial influences were primarily responsible for this reduction in erosive heating to gun barrel walls. The boundary layers were thickened by the additives and erosive diffusion gradients were correspondingly reduced. The isolated inertial mechanisms are now understood but are difficult to apply in general dimensional analysis scaling or in analytical heat transfer correlation predictions. Three major factors which contribute to these difficulties are: time dependence of both developing mean flow and particle field; turbulence-particle interactions; and thermochemical heat release and exchange between reactive gas components and particles, particles and wall surface, and reactive gas and wall surface. To help illustrate the influence of thes mechanisms and provide a basis for prediction, the influence of submicron additives in unsteady turbulent boundary layer growth and interaction regions adjacent to a model of a chemically active metallic (steel) surface are examined. Equilibrium chemistry is assumed for all phases.

  3. Effect of petroleum coke addition on coal gasification

    NASA Astrophysics Data System (ADS)

    Sinnathambi, Chandra Mohan; Najib, Nur Khadijah Mohamad

    2014-10-01

    The main fuel for power generation is combustion of coal and/or natural gas. Natural gas is expensive but clean and less problematic, whereas coal is the reverse of natural gas. Natural gas resources are expected to last until 2020 where else coal has another 200 years expectancy. To replace the natural gas, synthetic gas (syngas) can be used as a substitute fuel. Syngas can be produced using coal as fuel. In this study we blend petcoke, a cheap solid carboneous fuel as an alternative to coal for the production of syngas using a 30 Kwattheat bubbling fluidized bed gasifier. The equivalent ratio (ER) was set at 2.8 and a gasification temperature was maintained between 680 to 710°C by manipulating between the feed flow rates and fluidizing medium. This condition was chosen as it proved to be the optimum based on the work by the same group. Various blend of coal:petcoke between 0 to 100% was analyzed. It was found that a 20:80, petcoke to coal gives a good correlation with 100% coal gasification.

  4. Investigation of Fuel Additive Effects on Sooting Flames

    DTIC Science & Technology

    1989-07-28

    Ndubizu, C. C., and B. T. Zinn : Effects of Metallic Aditive Upon Soot Formation in Polymer Diffusion Flames. Combust, Flame 46, 301-314 (1982). 3.4...Plenum Press, New York, p. 143 (1981). 3.28 Wersborg, B. L., .1. B. Howard , and G. C. Williams: Physical Mechanisms in Carbon 3 Formation in Flames

  5. Nutrient additions in pristine Patagonian Sphagnum bog vegetation: can phosphorus addition alleviate (the effects of) increased nitrogen loads.

    PubMed

    Fritz, C; van Dijk, G; Smolders, A J P; Pancotto, V A; Elzenga, T J T M; Roelofs, J G M; Grootjans, A P

    2012-05-01

    Sphagnum-bog ecosystems have a limited capability to retain carbon and nutrients when subjected to increased nitrogen (N) deposition. Although it has been proposed that phosphorus (P) can dilute negative effects of nitrogen by increasing biomass production of Sphagnum mosses, it is still unclear whether P-addition can alleviate physiological N-stress in Sphagnum plants. A 3-year fertilisation experiment was conducted in lawns of a pristine Sphagnum magellanicum bog in Patagonia, where competing vascular plants were practically absent. Background wet deposition of nitrogen was low (≈ 0.1-0.2 g · N · m(-2) · year(-1)). Nitrogen (4 g · N · m(-2) · year(-1)) and phosphorus (1 g · P · m(-2) · year(-1)) were applied, separately and in combination, six times during the growing season. P-addition substantially increased biomass production of Sphagnum. Nitrogen and phosphorus changed the morphology of Sphagnum mosses by enhancing height increment, but lowering moss stem density. In contrast to expectations, phosphorus failed to alleviate physiological stress imposed by excess nitrogen (e.g. amino acid accumulation, N-saturation and decline in photosynthetic rates). We conclude that despite improving growth conditions by P-addition, Sphagnum-bog ecosystems remain highly susceptible to nitrogen additions. Increased susceptibility to desiccation by nutrients may even worsen the negative effects of excess nitrogen especially in windy climates like in Patagonia.

  6. Quantifying Main Trends in Lysozyme Nucleation: The Effect of Precipitant Concentration and Impurities

    NASA Technical Reports Server (NTRS)

    Burke, Michael W.; Judge, Russell A.; Pusey, Marc L.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    Full factorial experiment design incorporating multi-linear regression analysis of the experimental data allows the main trends and effects to be quickly identified while using only a limited number of experiments. These techniques were used to identify the effect of precipitant concentration and the presence of an impurity, the physiological lysozyme dimer, on the nucleation rate and crystal dimensions of the tetragonal form of chicken egg white lysozyme. Increasing precipitant concentration was found to decrease crystal numbers, the magnitude of this effect also depending on the supersaturation. The presence of the dimer generally increased nucleation. The crystal axial ratio decreased with increasing precipitant concentration independent of impurity.

  7. Main Effect QTL with Dominance Determines Heterosis for Dynamic Plant Height in Upland Cotton

    PubMed Central

    Shang, Lianguang; Ma, Lingling; Wang, Yumei; Su, Ying; Wang, Xiaocui; Li, Yuhua; Abduweli, Abdugheni; Cai, Shihu; Liu, Fang; Wang, Kunbo; Hua, Jinping

    2016-01-01

    Plant height, which shows dynamic development and heterosis, is a major trait affecting plant architecture and has an indirect influence on economic yield related to biological yield in cotton. In the present study, we carried out dynamic analysis for plant height and its heterosis by quantitative trait loci (QTL) mapping at multiple developmental stages using two recombinant inbred lines (RILs) and their backcross progeny. At the single-locus level, 47 QTL were identified at five developmental stages in two hybrids. In backcross populations, QTL identified at an early stage mainly showed partial effects and QTL detected at a later stage mostly displayed overdominance effects. At the two-locus level, we found that main effect QTL played a more important role than epistatic QTL in the expression of heterosis in backcross populations. Therefore, this study implies that the genetic basis of plant height heterosis shows dynamic character and main effect QTL with dominance determines heterosis for plant height in Upland cotton. PMID:27565885

  8. A simplified soil extraction sequence to monitor the main and trace element speciation in soil after compost and mineral fertilizer additions upon the composition of wheat grains

    NASA Astrophysics Data System (ADS)

    Sager, Manfred; Erhart, Eva

    2016-04-01

    High quality biological waste treatment aims at producing compost in order to maintain a clean environment and to sustain soil organic carbon levels. Fertilization with compost as a source of organic carbon, nutrients, and accessory elements, as well as fertilization with mineral N- and PK fertilizer have been tested in a field experiment on a calcaric Fluvisol in the Danube wetlands, at 4 levels each. Yields of wheat were recorded, and grains and soils were sampled from each treatment, and analyzed for main and trace element composition. The corresponding soils were characterized by mobile phases, obtained by leaching with 0,16M acetic acid to cover exchangeables plus carbonates, and subsequently by 0,1M oxalate buffer pH 3 to dissolve the pedogenic oxides. Total amounts were obtained from digests with perchloric- nitric-hydrofluoric acid. For quasi-total amounts, aqua regia was replaced by pressure decomposition with KClO3 in dilute nitric acid. The proposed extraction sequence permits to analyze and interpret soil for main elements, trace elements, nutrients and anions simultaneously. Factor analyses of soil extracts obtained from dilute acetic acid revealed Ba-Be-Cd-Cu-Li-S (traces), Ca-Mg-Mn (main carbonates), Al-Fe-B, Y, and P-K (nutrients) as chemically feasible principal components. Subsequent soil extracts from oxalate contained Al-B-Co-K-Na-Pb-Si-V-S (maybe acid silicate weathering), Cr-Li-Ni-Sr-Ti (maybe basic silicate weathering), Be-Cu-Fe-P, Co-Mg-Mn-Zn (Mn-oxides) and Ba-Sc as principal components. Factor analyses of total element data distinguished the principal components Ce-La-Li-Sc-Y-P (rare earths), Al-Ca-Fe-K-Mg-Na-P (main elements), Cd-Co-Cr-Cu-Ni-Zn (trace elements), As-Pb (contaminants), Ba-Mn-Sr, and Ti, which looks chemically feasible also. Factor analyses of those soil fractions which presumably form the main fractions of exchangeables, carbonates, pedogenic oxides and silicates, showed no cross connections, except for P. Oxalate

  9. Effects of the addition of dimer acid alkyl esters on the properties of ethyl cellulose.

    PubMed

    Lee, Sangjun; Ko, Kwang-Hwan; Shin, Jihoon; Kim, Nam-Kyun; Kim, Young-Wun; Kim, Joon-Seop

    2015-05-05

    In this study, we synthesized dimer acid (DA) esters, having short to long alkyl chains, (DA-Cn) by the Diels-Alder reaction and subsequent esterification reaction of fatty acids that were prepared by the hydrolysis of waste vegetable oil. It was found that the DA-Cn were thermally more stable than common petroleum-based plasticizer DOP. When the DOP, DA, or DA-Cn with short alkyl chains were added to ethyl cellulose (EC), the optical clarity and SEM images of the samples showed their good miscibility with those additives in a micro-scale. It was also found that the rubbery modulus of the EC decreased with increasing amount of additives; the type of the additives did not affect the rates of the decrease in the rubbery modulus. The main transition temperatures of the EC containing either DA or DA-C1 or DA-C4 decreased with increasing amounts of those additives and were comparable to that of the DOP-containing EC. The above findings suggested that the DA and its esters with short alkyl chains could act as effective plasticizer and, thus, could be used instead of the DOP. In addition, the results obtained from tensile testing and leaching experiments implied that the DA might be better plasticizer than the DA-C1 and DA-C4, at least in some cases, because of hydrogen-bonding with the EC.

  10. Gamma radiation effects on siloxane-based additive manufactured structures

    NASA Astrophysics Data System (ADS)

    Schmalzer, Andrew M.; Cady, Carl M.; Geller, Drew; Ortiz-Acosta, Denisse; Zocco, Adam T.; Stull, Jamie; Labouriau, Andrea

    2017-01-01

    Siloxane-basedadditive manufactured structures prepared by the direct ink write (DIW) technology were exposed to ionizing irradiation in order to gauge radiolysis effects on structure-property relationships. These well-defined 3-D structures were subjected to moderate doses of gamma irradiation in an inert atmosphere and characterized by a suite of experimental methods. Changes in thermal, chemical, microstructure, and mechanical properties were evaluated by DSC, TGA, FT-IR, mass spectroscopy, EPR, solvent swelling, SEM, and uniaxial compressive load techniques. Our results demonstrated that 3-D structures made from aromatic-free siloxane resins exhibited hardening after being exposed to gamma radiation. This effect was accompanied by gas evolution, decreasing in crystallization levels, decreasing in solvent swelling and damage to the microstructure. Furthermore, long-lived radiation-induced radicals were not detected by EPR methods. Our results are consistent with cross-link formation being the dominant degradation mechanism over chain scission reactions. On the other hand, 3-D structures made from high phenyl content siloxane resins showed little radiation damage as evidenced by low off gassing.

  11. Effects of V addition on recrystallization resistance of 7150 aluminum alloy after simulative hot deformation

    SciTech Connect

    Lai, Jing; Shi, Cangji; Chen, X.-Grant

    2014-10-15

    The effects of different V contents (0.01 to 0.19 wt.%) on the recrystallization resistance of 7150 aluminum alloys during post-deformation heat treatment were investigated. The microstructural evolutions at as-cast, as-homogenized conditions and after post-deformation annealing were studied using optical, scanning electron and transmission electron microscopes and using the electron backscattered diffraction technique. The precipitation of Al{sub 21}V{sub 2} dispersoids was observed in alloys containing 0.11 to 0.19 wt.% V after homogenization. The dispersoids were mainly distributed in the dendrite cells, and the precipitate-free zones occurred in the interdendritic regions and near grain boundaries. V addition could significantly enhance the recrystallization resistance during post-deformation annealing, particularly in the presence of a great number of Al{sub 21}V{sub 2} dispersoids. Recrystallized grain growth was effectively restricted because of the dispersoid pinning effect. The alloy containing 0.15 wt.% V exhibited the highest recrystallization resistance amongst all V-containing alloys studied. - Highlights: • Investigated the effect of V level on microstructure and flow stress of 7150 alloys • Characterized microstructures using optical microscopy, SEM, TEM and EBSD • Described the precipitation behavior of V-dispersoids in the dendritic structure • Studied the V effect on recrystallization resistance during post heat treatment • V addition greatly enhanced the recrystallization resistance during annealing.

  12. Effects on Diagnostic Parameters After Removing Additional Synchronous Gear Meshes

    NASA Technical Reports Server (NTRS)

    Decker, Harry J.

    2003-01-01

    Gear cracks are typically difficult to diagnose with sufficient time before catastrophic damage occurs. Significant damage must be present before algorithms appear to be able to detect the damage. Frequently there are multiple gear meshes on a single shaft. Since they are all synchronous with the shaft frequency, the commonly used synchronous averaging technique is ineffective in removing other gear mesh effects. Carefully applying a filter to these extraneous gear mesh frequencies can reduce the overall vibration signal and increase the accuracy of commonly used vibration metrics. The vibration signals from three seeded fault tests were analyzed using this filtering procedure. Both the filtered and unfiltered vibration signals were then analyzed using commonly used fault detection metrics and compared. The tests were conducted on aerospace quality spur gears in a test rig. The tests were conducted at speeds ranging from 2500 to 5000 revolutions per minute and torques from 184 to 228 percent of design load. The inability to detect these cracks with high confidence results from the high loading which is causing fast fracture as opposed to stable crack growth. The results indicate that these techniques do not currently produce an indication of damage that significantly exceeds experimental scatter.

  13. Pilot Study of Sublethal Effects on Fish of Pesticides Currently Used and Proposed for Use on Maine Blueberries

    USGS Publications Warehouse

    Elskus, Adria A.

    2007-01-01

    Blueberry pesticides have been detected consistently in some Down East Maine rivers, yet little is known about the sublethal effects of these pesticides on fish early life stages. The Maine blueberry industry is proposing to replace the insecticide ImidanTM (active ingredient phosmet) and the herbicide VelparTM (active ingredient hexazinone), two of the pesticides found in these rivers, with candidate alternatives SpinTor TM (active ingredient spinosad) and Callistso TM (active ingredient mesotrione). Our objective is to evaluate potential sublethal effects of these four formulations before the industry adopts the two candidate alternatives. We exposed zebrafish (Danio rerio) early life stages, from fertilization through larval swim-up, to a range of pesticide concentrations and evaluated their response relative to untreated controls. In this report we provide preliminary data on immune function as well as on parameters in addition to those originally proposed: development and performance fitness. We also provide information on our progress towards optimizing chemical protocols for analyzing the concentration of active ingredient in each of our formulation dosing solutions, another new parameter we added to those originally proposed. Preliminary results indicate that at environmentally realistic concentrations, these pesticides may have no significant effect on innate immunity, development rate or behavior (spontaneous swimming), however further replication is needed to confirm these initial findings. We have also observed some degree of developmental abnormalities in both pesticide-treated and control zebrafish embryos; however, additional replication is underway to determine if these groups differ significantly.

  14. Quantifying Main Trends in Lysozyme Nucleation: The Effects of Precipitant Concentration, Supersaturation and Impurities

    NASA Technical Reports Server (NTRS)

    Burke, Michael W.; Leardi, Riccardo; Judge, Russell A.; Pusey, Marc L.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    Full factorial experimental design incorporating multi-linear regression analysis of the experimental data allows quick identification of main trends and effects using a limited number of experiments. In this study these techniques were employed to identify the effect of precipitant concentration, supersaturation, and the presence of an impurity, the physiological lysozyme dimer, on the nucleation rate and crystal dimensions of the tetragonal forin of chicken egg white lysozyme. Decreasing precipitant concentration, increasing supers aturation, and increasing impurity, were found to increase crystal numbers. The crystal axial ratio decreased with increasing precipitant concentration, independent of impurity.

  15. Effects of Silicon Substitution in the Main Chain Network Segments of Polycyanurates

    DTIC Science & Technology

    2012-03-28

    cure in silicone molds under N2, cure schedule for 1 hr at 150 °C followed by 24 hrs at 210 °C, with ramp rates at 5 °C / min. ESR255 BADCy SiMCy...Briefing Charts 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Effects of Silicon Substitution in the Main...National Meeting, San Diego, CA, 25-29 March 2012. 14. ABSTRACT This presentation summarizes the study of the effects of silicon substitution in both

  16. Some effects of quiet geomagnetic field changes upon values used for main field modeling

    USGS Publications Warehouse

    Campbell, W.H.

    1987-01-01

    The effects of three methods of data selection upon the assumed main field levels for geomagnetic observatory records used in main field modeling were investigated for a year of very low solar-terrestrial activity. The first method concerned the differences between the year's average of quiet day field values and the average of all values during the year. For H these differences were 2-3 gammas, for D they were -0.04 to -0.12???, for Z the differences were negligible. The second method of selection concerned the effects of the daytime internal Sq variations upon the daily mean values of field. The midnight field levels when the Sq currents were a minimum deviated from the daily mean levels by as much as 4-7 gammas in H and Z but were negligible for D. The third method of selection was designed to avoid the annual and semi-annual quiet level changes of field caused by the seasonal changes in the magnetosphere. Contributions from these changes were found to be as much as 4-7 gammas in quiet years and expected to be greater than 10 gammas in active years. Suggestions for improved methods of improved data selection in main field modeling are given. ?? 1987.

  17. Availability and Failure Effects of NLC Main Linac Mechanical Movers(LCC-0141)

    SciTech Connect

    Himel, T

    2004-05-24

    We analyze the probability of failure and the failure effects of the quadrupole and RF girder translation stages (''movers'') in the 500 GeV CM NLC Main Linac. In order to achieve its alignment tolerances, the NLC main linac will require a large installation of remote controlled translation stages with multiple degrees of freedom. In particular, each of the 591 quads in each 250 GeV main linac will be mounted on a magnet mover with 3 degrees of freedom (x, y, roll); each of the 2304 RF structure girders in each linac will be mounted on a girder mover with 5 degrees of freedom (x, y, roll, pitch, yaw). Simulation studies of main linac operation typically assume that all movers are operational at all times, in order to limit the complexity of the simulation. This is obviously not a realistic expectation for a system with so many components, especially when the number of sub-elements of each mover (stepper motors, rotary encoders, position transducers, cabling, control electronics, database, operator) are considered. The unavailability risk of the mover system is of particular concern for the NLC, since very few accelerators have ever been built with such a large fraction of its beamline hardware on remote-controlled translation stages. In order to predict the availability of the movers, it is necessary to estimate a few quantities, specifically: how often will a mover break (mean time between failures, or MTBF); how long will it take to repair a mover (mean time to repair, or MTTR); what is the performance ''hit'' which accrues when movers are broken? To answer the first two questions we used historical failure data from the two large mover systems at SLAC, in the arcs of the Stanford Linear Collider (SLC) and in the Final Focus Test Beam (FFTB). For the final question, we can get some estimate from simulation studies of the NLC main linac in normal operation.

  18. Effects of beta-glucan addition to a probiotic containing yogurt.

    PubMed

    Vasiljevic, T; Kealy, T; Mishra, V K

    2007-09-01

    This study investigated the effects of addition of beta-glucan from 2 different cereal sources (oat and barley) on growth and metabolic activity of Bifidobacterium animalis ssp. lactis (Bb-12) as determined by plating on a selective medium in yogurt during prolonged cold storage. These yogurt batches were compared to unsupplemented and inulin supplemented controls. All batches were also assessed for syneresis. Oat beta-glucan addition resulted in improved probiotic viability and stability comparable to that of inulin. It also enhanced lactic and propionic acid production. The barley beta-glucan addition suppressed proteolytic activity more than that from oat. These improvements were hindered by greater syneresis caused likely by thermodynamic incompatibility. Small amplitude oscillatory measurements of acidified model mixture of beta-glucan/skim milk solids showed formation of casein gel within the beta-glucan network. Binary mixtures of beta-glucan and skim milk solids had apparent pseudoplastic and non-Newtonian behavior governed mainly by beta-glucan contribution. Above critical concentrations, the mixtures underwent phase separation with the lower phase rich in protein. The phase diagram also showed that the addition of beta-glucan may be possible at or below 0.24 w/w%.

  19. Side effects of antibiotics during bacterial infection: mitochondria, the main target in host cell.

    PubMed

    Singh, Rochika; Sripada, Lakshmi; Singh, Rajesh

    2014-05-01

    Antibiotics are frontline therapy against microbial infectious diseases. Many antibiotics are known to cause several side effects in humans. Ribosomal RNA (rRNA) is the main target of antibiotics that inhibit protein synthesis. According to the endosymbiont theory, mitochondrion is of bacterial origin and their molecular and structural components of the protein expression system are almost similar. It has been observed that the rate of mutations in mitochondrial rRNA is higher as compared to that of nuclear rRNA. The presence of these mutations may mimic prokaryotic rRNA structure and bind to antibiotics targeted to ribosomes of bacteria. Mitochondrial functions are compromised hence may be one of the major causes of side effects observed during antibiotic therapy. The current review had summarized the studies on the role of antibiotics on mitochondrial functions and its relevance to the observed side effects in physiological and pathological conditions.

  20. Main alkaloids of Peganum harmala L. and their different effects on dicot and monocot crops.

    PubMed

    Shao, Hua; Huang, Xiaoli; Zhang, Yuanming; Zhang, Chi

    2013-02-27

    Alkaloids with allelopathic activity are not as well-known as other allelochemicals. Our study revealed that total alkaloids from seeds of the medicinal plant Peganum harmala L. possessed significant growth inhibitory effect on four treated plants, with dicot plants (lettuce and amaranth) being more sensitive than the tested monocot plants (wheat and ryegrass). Further investigation led to the isolation of harmaline and harmine as the main active ingredients in the total alkaloids of P. harmala seeds. Harmaline exerted potent inhibitory effects on seedling growth of treated plants, especially dicots, inhibiting root elongation of lettuce and amaranth by 31% and 47% at a very low concentration (5 µg/mL), whereas harmine exhibited much weaker non-selective inhibitory effect on the plants. Considering the high yield and poor utilization of P. harmala in China, we anticipate that this plant could be exploited as an alternative weed management tool in the future.

  1. Effect of Wiggler insertions on the single-particle dynamics of the NLC main damping rings

    SciTech Connect

    Venturini, Marco

    2003-07-30

    As they are expected to occupy a large portion of the lattice, wiggler insert ions will introduce significant linear and nonlinear perturbations to the single-particle dynamics in the NLC Main Damping Rings (MDR). The nonlinearities are of particular concern as a sufficiently large Dynamic Aperture (DA) is required for high injection efficiency. The main content of this report is a study of the wigglers impact on the DA of the NLC-MDR latest lattice design. The particle dynamics is modeled by transfer maps calculated by integration through the wiggler fields. For field representation we employed a 3D multipole expansion derived from the field data that were obtained with the aid of a magnet design code. Additional contents of this paper include an investigation of a simplified model of wiggler consisting of a sequence of standard magnet elements (where thin octupoles are used to represent the dominant nonlinearities) and the suggestion of a possible correction scheme to compensate the wiggler nonlinearities.

  2. Child maltreatment and violent delinquency: disentangling main effects and subgroup effects.

    PubMed

    Mersky, Joshua P; Reynolds, Arthur J

    2007-08-01

    This study employs data from the Chicago Longitudinal Study (CLS) to investigate the relation between child maltreatment and the incidence and frequency of violent delinquency. The authors also examine if effects vary between physically abused and neglected children and if select indicators (sex, cumulative risk, public aid receipt) moderate the connections between maltreatment and violent outcomes. The CLS follows a cohort of 1,539 low-income, minority children who attended public kindergarten programs in 1985-1986. The primary sample includes 1,404 participants for whom maltreatment and delinquency status were verified. Maltreatment is significantly associated with all violent outcomes investigated. Effects are comparable for physically abused and neglected children. Results indicate that public assistance, particularly persistent receipt, moderates the association between maltreatment and multiple outcomes. Findings support the hypothesized connection between maltreatment and violent delinquency while highlighting certain subgroups that may be at elevated risk. Implications for research design and program development are discussed.

  3. Simulations of Electron Cloud Effects on the Beam Dynamics for theFNAL Main Injector Upgrade

    SciTech Connect

    Sonnad Kiran G.; Furman, Miguel; Vay, Jean-Luc; Venturini, Marco; Celata, Christine M.; Grote, David

    2006-04-15

    The Fermilab main injector (MI) is being considered for an upgrade as part of the high intensity neutrino source (HINS) effort. This upgrade will involve a significant increasing of the bunch intensity relative to its present value. Such an increase will place the MI in a regime in which electron-cloud effects are expected to become important. We have used the electrostatic particle-in-cell code WARP, recently augmented with new modeling capabilities and simulation techniques, to study the dynamics of beam-electron cloud interaction. This work in progress involves a systematic assessment of beam instabilities due to the presence of electron clouds.

  4. Intestinal bacteria activate estrogenic effect of main constituents puerarin and daidzin of Pueraria thunbergiana.

    PubMed

    Park, Eun-Kyung; Shin, Jieun; Bae, Eun-Ah; Lee, Young-Chul; Kim, Dong-Hyun

    2006-12-01

    To understand the relationship between the metabolites and estrogenic activity of the main isoflavones puerarin and daidzin of the rhizome of Pueraria thunbergiana (PT, family Leguminosae), PT and its isoflavones were transformed by human intestinal bacteria and their estrogenic effects were investigated. All human fecal specimens hydrolyzed puerarin and daidzin to daidzein, but their hydrolyzing activities varied depending on the individuals. All intestinal bacteria isolated from human also hydrolyzed daidzin to daidzein, but a few bacteria transformed puerarin to daidzein. When the estrogenic effect of PT, puerarin and daidzin was compared with those of their metabolites, the metabolites more potently increased proliferation of MCF-7 cells than PT, puerarin and daidzin. The metabolite daidzein also potently increased estrogen-response c-fos mRNA and PR protein expressions. These findings suggest that intestinal bacteria, which can hydrolyze puerarin and/or daidzin, may activate a potent estrogenic activity of PT.

  5. Pharmacological and therapeutic effects of Mentha Longifolia L. and its main constituent, menthol

    PubMed Central

    Mikaili, Peyman; Mojaverrostami, Sina; Moloudizargari, Milad; Aghajanshakeri, Shahin

    2013-01-01

    Mentha longifolia (wild mint) is a popular folk remedy. Some parts of this plant have been used in traditional medicine of Iran and other countries. Many studies have shown various pharmacological and therapeutic effects of the plant. Our aim in preparing this study was to review the traditional uses of M. longifolia together with the pharmacological and therapeutic effects of its entire extract and major compounds. Mentha longifolia is an herb with a wide range of pharmacological properties such as antimicrobial, gastrointestinal, and nervous system effects. Pulegone is the main compound of the plant responsible for most of its pharmacological effects followed by menthone, isomenthone, menthol, 1, 8-cineole, borneol, and piperitenone. Moreover, the plant may dose-dependently exert toxic effects in different systems of the body. Based on the review of various studies, it can be concluded that M. longifolia is a potential natural source for the development of new drugs. However, further studies are required to determine the precise quality and safety of the plant to be used by clinicians. PMID:25284948

  6. Synergistic, additive, and antagonistic effects of food mixtures on total antioxidant capacities.

    PubMed

    Wang, Sunan; Meckling, Kelly A; Marcone, Massimo F; Kakuda, Yukio; Tsao, Rong

    2011-02-09

    Different foods possess different bioactive compounds with varied antioxidant capacities. When foods are consumed together, the total antioxidant capacity of food mixtures may be modified via synergistic, additive, or antagonistic interactions among these components, which may in turn alter their physiological impacts. The main objective of this study was to investigate these interactions and identify any synergistic combinations. Eleven foods from three categories, including fruits (raspberry, blackberry, and apple), vegetables (broccoli, tomato, mushroom, and purple cauliflower), and legumes (soybean, adzuki bean, red kidney bean, and black bean) were combined in pairs. Four assays (total phenolic content, ferric reducing antioxidant power, 2,2-diphenyl-1-picrylhydrazyl, radical scavenging capacity, and oxygen radical absorbance capacity) were used to evaluate the antioxidant capacities of individual foods and their combinations. The results indicated that within the same food category, 13, 68, and 21% of the combinations produced synergistic, additive, and antagonistic interactions, respectively, while the combinations produced 21, 54, and 25% synergistic, additive, and antagonistic effects, respectively, across food categories. Combining specific foods across categories (e.g., fruit and legume) was more likely to result in synergistic antioxidant capacity than combinations within a food group. Combining raspberry and adzuki bean extracts demonstrated synergistic interactions in all four chemical-based assays. Compositional changes did not seem to have occurred in the mixture. Results in this study suggest the importance of strategically selecting foods or diets to maximum synergisms as well as to minimum antagonisms in antioxidant activity.

  7. Contrasting effects of nitrogen and phosphorus addition on soil respiration in an alpine grassland on the Qinghai-Tibetan Plateau

    PubMed Central

    Ren, Fei; Yang, Xiaoxia; Zhou, Huakun; Zhu, Wenyan; Zhang, Zhenhua; Chen, Litong; Cao, Guangmin; He, Jin-Sheng

    2016-01-01

    High soil organic carbon content, extensive root biomass, and low nutrient availability make alpine grasslands an important ecosystem for assessing the influence of nutrient enrichment on soil respiration (SR). We conducted a four-year (2009–2012) field experiment in an alpine grassland on the Qinghai-Tibetan Plateau to examine the individual and combined effects of nitrogen (N, 100 kg ha−1year−1) and phosphorus (P, 50 kg ha−1year−1) addition on SR. We found that both N and P addition did not affect the overall growing-season SR but effects varied by year: with N addition SR increased in the first year but decreased during the last two years. However, while P addition did not affect SR during the first two years, SR increased during the last two years. No interactive effects of N and P addition were observed, and both N addition and P addition reduced heterotrophic respiration during the last year of the experiment. N and P addition affected SR via different processes: N mainly affected heterotrophic respiration, whereas P largely influenced autotrophic respiration. Our results highlight the divergent effects of N and P addition on SR and address the important potential of P enrichment for regulating SR and the carbon balance in alpine grasslands. PMID:27721415

  8. Evaluating the main and side effects of high salinity on aerobic granular sludge.

    PubMed

    Pronk, M; Bassin, J P; de Kreuk, M K; Kleerebezem, R; van Loosdrecht, M C M

    2014-02-01

    Salinity can adversely affect the performance of most biological processes involved in wastewater treatment. The effect of salt on the main conversion processes in an aerobic granular sludge (AGS) process accomplishing simultaneous organic matter, nitrogen, and phosphate removal was evaluated in this work. Hereto, an AGS sequencing batch reactor was subjected to different salt concentrations (0.2 to 20 g Cl(-) l(-1)). Granular structure was stable throughout the whole experimental period, although granule size decreased and a significant effluent turbidity was observed at the highest salinity tested. A weaker gel structure at higher salt concentrations was hypothesised to be the cause of such turbidity. Ammonium oxidation was not affected at any of the salt concentrations applied. However, nitrite oxidation was severely affected, especially at 20 g Cl(-) l(-1), in which a complete inhibition was observed. Consequently, high nitrite accumulation occurred. Phosphate removal was also found to be inhibited at the highest salt concentration tested. Complementary experiments have shown that a cascade inhibition effect took place: first, the deterioration of nitrite oxidation resulted in high nitrite concentrations and this in turn resulted in a detrimental effect to polyphosphate-accumulating organisms. By preventing the occurrence of the nitrification process and therefore avoiding the nitrite accumulation, the effect of salt concentrations on the bio-P removal process was shown to be negligible up to 13 g Cl(-) l(-1). Salt concentrations equal to 20 g Cl(-) l(-1) or higher in absence of nitrite also significantly reduced phosphate removal efficiency in the system.

  9. Gastrointestinal effects of Nigella sativa and its main constituent, thymoquinone: a review

    PubMed Central

    Shakeri, Farzaneh; Gholamnezhad, Zahra; Mégarbane, Bruno; Rezaee, Ramin; Boskabady, Mohammad Hosein

    2016-01-01

    Gastrointestinal (GI) diseases affect a large number of people all over the world. Uncontrolled acid secretion and occurrence of gastric ulcers are common disorders of GI tract which pose serious problems to human health. Many synthetic drugs have been used to treat GI disorders but a definite cure has not been discovered so far and the available medications cause several side effects. Nigella sativa (N. sativa) (Ranunculacea) has several therapeutic effects which are attributed to its constituents like nigellicine, nigellidine, thymoquinone, dithymoquinone, thymol and carvacrol. Several beneficial pharmacological properties of this plant such as anti-oxidant, anti-bacterial, anti-histaminic, anti-hypertensive, hypoglycemic, anti-fungal, anti-inflammatory, anti-cancer and immunomodulatory effects were reported and different therapeutic properties such as reliving bronchial asthma, jaundice, hydrophobia, paralysis, conjunctivitis, piles, skin diseases, anorexia, headache, dysentery, infections, obesity, back pain, hypertension and gastrointestinal problems, have been described for the seeds of N. sativa and its oil. The present review provides a detailed summery of scientific researches regarding gastrointestinal effect of N. sativa and its main constituent, thymoquinone. PMID:27247918

  10. Gastrointestinal effects of Nigella sativa and its main constituent, thymoquinone: a review.

    PubMed

    Shakeri, Farzaneh; Gholamnezhad, Zahra; Mégarbane, Bruno; Rezaee, Ramin; Boskabady, Mohammad Hosein

    2016-01-01

    Gastrointestinal (GI) diseases affect a large number of people all over the world. Uncontrolled acid secretion and occurrence of gastric ulcers are common disorders of GI tract which pose serious problems to human health. Many synthetic drugs have been used to treat GI disorders but a definite cure has not been discovered so far and the available medications cause several side effects. Nigella sativa (N. sativa) (Ranunculacea) has several therapeutic effects which are attributed to its constituents like nigellicine, nigellidine, thymoquinone, dithymoquinone, thymol and carvacrol. Several beneficial pharmacological properties of this plant such as anti-oxidant, anti-bacterial, anti-histaminic, anti-hypertensive, hypoglycemic, anti-fungal, anti-inflammatory, anti-cancer and immunomodulatory effects were reported and different therapeutic properties such as reliving bronchial asthma, jaundice, hydrophobia, paralysis, conjunctivitis, piles, skin diseases, anorexia, headache, dysentery, infections, obesity, back pain, hypertension and gastrointestinal problems, have been described for the seeds of N. sativa and its oil. The present review provides a detailed summery of scientific researches regarding gastrointestinal effect of N. sativa and its main constituent, thymoquinone.

  11. Additive effect of linseed oil supplementation on the lipid profiles of older adults

    PubMed Central

    Avelino, Ana Paula A; Oliveira, Gláucia MM; Ferreira, Célia CD; Luiz, Ronir R; Rosa, Glorimar

    2015-01-01

    Background Linseed oil has been investigated as a rich source of n-3 series polyunsaturated fatty acids, which mainly produce a non-atherogenic lipid profile. The objective of this study was to investigate the effect of linseed oil supplementation associated with nutritional guidelines on the lipid profiles of older adults, according to the intake of saturated fatty acids (SFA). Methods We conducted a double-blind, placebo-controlled clinical trial with 110 older adults randomized in two groups: placebo and linseed oil. The linseed oil group received supplementation with 3 g of linseed oil. Both groups received nutritional guidance and were supplemented for 90 days with monthly blood collection for biochemical analysis. The dietary intake of saturated fat was subdivided into low (<7% SFA/day of the total energy value) and high consumption groups (>7% SFA/day of the total energy value). Results Low SFA (<7% SFA/day of total energy value) consumption was associated with lower total cholesterol concentrations. However, we observed that the linseed oil group, including older adults who consumed >7% SFA/day, had a greater reduction in total cholesterol than the placebo group (P=0.020). The same was observed for low-density lipoprotein (LDL) cholesterol (P<0.050), suggesting an additive effect of linseed oil and diet. High-density lipoprotein (HDL) cholesterol concentrations were increased significantly in only the linseed group, suggesting that the nutritional intervention alone did not improve HDL cholesterol. Conclusion The results suggest that the nutritional intervention was effective, but linseed oil showed notable effects by increasing the HDL cholesterol concentration. In addition, consumption of <7% SFA/day of the total energy value increased the effect of linseed oil, demonstrating the importance of reducing the consumption of saturated fat. PMID:26543357

  12. Effect of Catnip Charcoal on the In Vivo Pharmacokinetics of the Main Alkaloids of Rhizoma Coptidis

    PubMed Central

    He, Yanfei; Chen, Siyu; Yu, Hai; Zhu, Long; Liu, Yayun; Han, Chunyang; Liu, Cuiyan

    2016-01-01

    This study aims to explore the effect of catnip Nepeta cataria (CNC) charcoal on the pharmacokinetics of the main alkaloids of Rhizoma Coptidis in vivo. Twenty-four rabbits were randomly divided into four groups and given oral administration of an aqueous extract of Rhizoma Coptidis (RCAE), RCAE plus CNC, RCAE plus activated carbon (AC), or distilled water, respectively. Plasma samples were collected after administration. The concentrations of berberine, coptisine, palmatine, and epiberberine in plasma were measured by high-performance liquid chromatography (HPLC). The pharmacokinetics data were calculated using pharmacokinetic DAS 2.0 software. The results showed that the area under the concentration-time curve (AUC) of berberine increased, while the AUC of coptisine, palmatine, and epiberberine decreased in the rabbits that received RCAE plus CNC. Meanwhile, the AUC of berberine, coptisine, palmatine, and epiberberine decreased in the group given RCAE plus AC. The difference of main pharmacokinetics parameters among the four groups was significant (P < 0.05). This study showed that CNC improved the bioavailability of berberine in comparison to AC and prolonged its release in comparison to RCAE alone. However, it decreased the bioavailability of coptisine, palmatine, and epiberberine. In comparison, AC uniformly declined the bioavailability of berberine, coptisine, palmatine, and epiberberine. PMID:27313645

  13. Effect of Catnip Charcoal on the In Vivo Pharmacokinetics of the Main Alkaloids of Rhizoma Coptidis.

    PubMed

    He, Yanfei; Chen, Siyu; Yu, Hai; Zhu, Long; Liu, Yayun; Han, Chunyang; Liu, Cuiyan

    2016-01-01

    This study aims to explore the effect of catnip Nepeta cataria (CNC) charcoal on the pharmacokinetics of the main alkaloids of Rhizoma Coptidis in vivo. Twenty-four rabbits were randomly divided into four groups and given oral administration of an aqueous extract of Rhizoma Coptidis (RCAE), RCAE plus CNC, RCAE plus activated carbon (AC), or distilled water, respectively. Plasma samples were collected after administration. The concentrations of berberine, coptisine, palmatine, and epiberberine in plasma were measured by high-performance liquid chromatography (HPLC). The pharmacokinetics data were calculated using pharmacokinetic DAS 2.0 software. The results showed that the area under the concentration-time curve (AUC) of berberine increased, while the AUC of coptisine, palmatine, and epiberberine decreased in the rabbits that received RCAE plus CNC. Meanwhile, the AUC of berberine, coptisine, palmatine, and epiberberine decreased in the group given RCAE plus AC. The difference of main pharmacokinetics parameters among the four groups was significant (P < 0.05). This study showed that CNC improved the bioavailability of berberine in comparison to AC and prolonged its release in comparison to RCAE alone. However, it decreased the bioavailability of coptisine, palmatine, and epiberberine. In comparison, AC uniformly declined the bioavailability of berberine, coptisine, palmatine, and epiberberine.

  14. Inhibitory Effects of the Four Main Theaflavin Derivatives Found in Black Tea on Ovarian Cancer Cells

    PubMed Central

    GAO, YING; RANKIN, GARY O.; TU, YOUYING; CHEN, YI CHARLIE

    2016-01-01

    Background Some polyphenols induce apoptosis and inhibit angiogenesis. Consumption of black tea, rich in polyphenols, has been found to reduce ovarian cancer risk. Theaflavin (TF1), theaflavin-3-gallate (TF2a), theaflavin-3′-gallate (TF2b) and theaflavin-3, 3′-digallate (TF3) are four main theaflavin derivatives found in black tea. Materials and Methods Cell proliferation assay, Hoechst 33342 staining assay, Caspase-Glo Assay, western blot, human umbilical vein endothelial cell tube formation assay and vascular endothelial growth factor (VEGF) enzyme-linked immunosorbent assay were performed. Results All four theaflavin derivatives reduced viability of ovarian cancer cells at lower concentrations than with normal ovarian cells. TF1 mainly mediated apoptosis via the intrinsic pathway, while the others via the intrinsic and extrinsic pathways. TF1 inhibited tube formation via reducing VEGF secretion in a hypoxia-inducible factor 1α-independent manner, while the others in a HIF1α-dependent way. Conclusion All four theaflavin derivatives inhibited ovarian cancer cells. Some of the effects and mechanisms of TF1 are different from those of the other three theaflavin derivatives. PMID:26851019

  15. The effects of breathing with mainly inspiration or expiration on pulmonary function and chest expansion

    PubMed Central

    Woo, Seong-Dae; Kim, Tae-Ho; Lim, Jin-Yong

    2016-01-01

    [Purpose] This study aimed to determine the effects of inspiration- and expiration-oriented breathing on pulmonary function and chest expansion. [Subjects and Methods] Twenty healthy male university students were divided randomly into inspiration-oriented and expiration-oriented breathing groups. Their pulmonary function and chest size during inspiration or expiration were evaluated and then re-evaluated after 15 minutes of breathing exercise five times a week for four weeks. [Results] The breathing with mainly inspiration group (BMIG) showed significant differences in chest size during inspiration (CSI), chest expansion values (CEVs), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and peak expiratory flow (PEF) after four weeks. The breathing with mainly expiration group (BMEG) showed significant differences in all measured variables except CSI. Comparison of the groups after exercise showed that the BMEG demonstrated differences from the BMIG in chest size during expiration (CSE), CEV, and PEF. Comparison of the changes in variables after exercise showed that the BMEG demonstrated significantly different changes in CSE, CEV, FEV1/FVC, and PEF. The BMIG showed a significantly different change in FVC. [Conclusion] Although both groups demonstrated improvements in pulmonary function and chest expansion, inter-group differences were observed. Therefore, inspiration- or expiration-oriented breathing may be recommended differently according to the desired outcome. PMID:27134386

  16. Pharmacological and therapeutic effects of Peganum harmala and its main alkaloids

    PubMed Central

    Moloudizargari, Milad; Mikaili, Peyman; Aghajanshakeri, Shahin; Asghari, Mohammad Hossein; Shayegh, Jalal

    2013-01-01

    Wild Syrian rue (Peganum harmala L. family Zygophyllaceae) is well-known in Iran and various parts of this plant including, its seeds, bark, and root have been used as folk medicine. Recent years of research has demonstrated different pharmacological and therapeutic effects of P. harmala and its active alkaloids, especially harmine and harmaline. Analytical studies on the chemical composition of the plant show that the most important constituents of this plant are beta-carboline alkaloids such as harmalol, harmaline, and harmine. Harmine is the most studied among these naturally occurring alkaloids. In addition to P. harmala (Syrian rue), these beta-carbolines are present in many other plants such as Banisteria caapi and are used for the treatment of different diseases. This article reviews the traditional uses and pharmacological effects of total extract and individual active alkaloids of P. harmala (Syrian rue). PMID:24347928

  17. Pharmacological and therapeutic effects of Peganum harmala and its main alkaloids.

    PubMed

    Moloudizargari, Milad; Mikaili, Peyman; Aghajanshakeri, Shahin; Asghari, Mohammad Hossein; Shayegh, Jalal

    2013-07-01

    Wild Syrian rue (Peganum harmala L. family Zygophyllaceae) is well-known in Iran and various parts of this plant including, its seeds, bark, and root have been used as folk medicine. Recent years of research has demonstrated different pharmacological and therapeutic effects of P. harmala and its active alkaloids, especially harmine and harmaline. Analytical studies on the chemical composition of the plant show that the most important constituents of this plant are beta-carboline alkaloids such as harmalol, harmaline, and harmine. Harmine is the most studied among these naturally occurring alkaloids. In addition to P. harmala (Syrian rue), these beta-carbolines are present in many other plants such as Banisteria caapi and are used for the treatment of different diseases. This article reviews the traditional uses and pharmacological effects of total extract and individual active alkaloids of P. harmala (Syrian rue).

  18. Vibration effects of the space shuttle main engine high pressure oxidizer turbopump bellows

    NASA Technical Reports Server (NTRS)

    Harp, J. A.

    1978-01-01

    A welded metal bellows was subjected to a series of vibration tests in a 400 psi oxygen environment to evaluate the effects of the bellows convolutes rubbing on the damper ring in the high pressure oxidizer turbopump of the space shuttle main engine. The bellows was subjected to approximately 2 million cycles at 0.007 in. double amplitude displacement during this series of tests, at a frequency of 400 Hz. Intrumentation of the test specimen revealed no significant heat buildup caused by the rubbing of the bellows convolutes on the damper ring. A final destruct test was made to determine if a fire would result if the bellows ruptured in the 400 psi oxygen environment, thus exposing a fresh metal surface. The vibration input was changed to 0.8 in. double amplitude displacement at 20 Hz to intentionally rupture the bellows. Failure occurred after 2.5 sec; no fire or heat buildup was encountered.

  19. Ab initio effective core potentials for molecular calculations. Potentials for main group elements Na to Bi

    SciTech Connect

    Wadt, W.R.; Hay, P.J.

    1985-01-01

    A consistent set of ab initio effective core potentials (ECP) has been generated for the main group elements from Na to Bi using the procedure originally developed by Kahn. The ECP's are derived from all-electron numerical Hartree--Fock atomic wave functions and fit to analytical representations for use in molecular calculations. For Rb to Bi the ECP's are generated from the relativistic Hartree--Fock atomic wave functions of Cowan which incorporate the Darwin and mass--velocity terms. Energy-optimized valence basis sets of (3s3p) primitive Gaussians are presented for use with the ECP's. Comparisons between all-electron and valence-electron ECP calculations are presented for NaF, NaCl, Cl/sub 2/, Cl/sub 2//sup -/, Br/sub 2/, Br/sub 2//sup -/, and Xe/sub 2//sup +/. The results show that the average errors introduced by the ECP's are generally only a few percent.

  20. Aromatase inhibiting and combined estrogenic effects of parabens and estrogenic effects of other additives in cosmetics

    SciTech Connect

    Meeuwen, J.A. van Son, O. van; Piersma, A.H.; Jong, P.C. de; Berg, M. van den

    2008-08-01

    There is concern widely on the increase in human exposure to exogenous (anti)estrogenic compounds. Typical are certain ingredients in cosmetic consumer products such as musks, phthalates and parabens. Monitoring a variety of human samples revealed that these ingredients, including the ones that generally are considered to undergo rapid metabolism, are present at low levels. In this in vitro research individual compounds and combinations of parabens and endogenous estradiol (E{sub 2}) were investigated in the MCF-7 cell proliferation assay. The experimental design applied a concentration addition model (CA). Data were analyzed with the estrogen equivalency (EEQ) and method of isoboles approach. In addition, the catalytic inhibitory properties of parabens on an enzyme involved in a rate limiting step in steroid genesis (aromatase) were studied in human placental microsomes. Our results point to an additive estrogenic effect in a CA model for parabens. In addition, it was found that parabens inhibit aromatase. Noticeably, the effective levels in both our in vitro systems were far higher than the levels detected in human samples. However, estrogenic compounds may contribute in a cumulative way to the circulating estrogen burden. Our calculation for the extra estrogen burden due to exposure to parabens, phthalates and polycyclic musks indicates an insignificant estrogenic load relative to the endogenous or therapeutic estrogen burden.

  1. Teratogenic Effect of Verbascoside, Main Constituent of Lippia citriodora Leaves, in Mice

    PubMed Central

    Etemad, Leila; Zafari, Reza; Moallem, Seyed Adel; Vahdati-Mashhadian, Naser; Skouei Shirvan, Zahra; Hosseinzadeh, Hossein

    2016-01-01

    Verbascoside (acteoside), a phenyl propanoid glycoside, comprises 0.5 to 3.5 % dry weight of Lippia citriodora leaves. A wide range of biological activities are attributed to verbascoside including anti-inflammatory, antioxidant, anti-bacterial, anti-tumor, anti-fungal, photoprotective as well as chelating effects. The objective of this study is to evaluate the effect of verbascoside on pregnancy outcome in mice. Timed-pregnant mice received doses of 1g/kg/day verbascoside or the vehicle control during organogenesis, intraperitoneally. Maternal body weights were measured throughout pregnancy. The litters were examined for external malformations and skeletal abnormalities. Then they were stained with Alizarin red S and Alcian blue. Maternal exposure to verbascoside throughout pregnancy did not influence the mean of maternal weight gain. Statistically significant difference was not found in mean number of implantation sites, live and resorbed fetuses between control and experiment groups. Our data demonstrate that the main component of L. citriodora, verbascoside using during organogenesis possesses no risk to fetuses. However, more research projects are needed to confirm these findings and determine the exact effects of verbascoside on human embryo development. PMID:27642323

  2. Teratogenic Effect of Verbascoside, Main Constituent of Lippia citriodora Leaves, in Mice.

    PubMed

    Etemad, Leila; Zafari, Reza; Moallem, Seyed Adel; Vahdati-Mashhadian, Naser; Skouei Shirvan, Zahra; Hosseinzadeh, Hossein

    2016-01-01

    Verbascoside (acteoside), a phenyl propanoid glycoside, comprises 0.5 to 3.5 % dry weight of Lippia citriodora leaves. A wide range of biological activities are attributed to verbascoside including anti-inflammatory, antioxidant, anti-bacterial, anti-tumor, anti-fungal, photoprotective as well as chelating effects. The objective of this study is to evaluate the effect of verbascoside on pregnancy outcome in mice. Timed-pregnant mice received doses of 1g/kg/day verbascoside or the vehicle control during organogenesis, intraperitoneally. Maternal body weights were measured throughout pregnancy. The litters were examined for external malformations and skeletal abnormalities. Then they were stained with Alizarin red S and Alcian blue. Maternal exposure to verbascoside throughout pregnancy did not influence the mean of maternal weight gain. Statistically significant difference was not found in mean number of implantation sites, live and resorbed fetuses between control and experiment groups. Our data demonstrate that the main component of L. citriodora, verbascoside using during organogenesis possesses no risk to fetuses. However, more research projects are needed to confirm these findings and determine the exact effects of verbascoside on human embryo development.

  3. A review of Neuropharmacology Effects of Nigella sativa and Its Main Component, Thymoquinone.

    PubMed

    Javidi, Soheila; Razavi, Bibi Marjan; Hosseinzadeh, Hossein

    2016-08-01

    Neuropharmacology is the scientific study of drug effect on nervous system. In the last few years, different natural plants and their active constituents have been used in neurological therapy. The availability, lower price, and less toxic effects of herbal medicines compared with synthetic agents make them as simple and excellent choice in the treatment of nervous diseases. Nigella sativa, which belongs to the botanical family of Ranunculaceae, is a widely used medicinal plant all over the world. In traditional and modern medicines several beneficial properties have been attributed to N. sativa and its main component, thymoquinone (TQ). In this review, various studies in scientific databases regarding the neuropharmacological aspects of N. sativa and TQ have been introduced. Results of these studies showed that N. sativa and TQ have several properties including anticonvulsant, antidepressant, anxiolytic, anti-ischemic, analgesic, antipsychotic, and memory enhancer. Furthermore, its protective effects against neurodegenerative diseases such as Alzheimer, Parkinson and multiple sclerosis have been discussed. Although there are many studies indicating the beneficial actions of this plant in nervous system, the number of research projects relating to the human reports is rare. Copyright © 2016 John Wiley & Sons, Ltd.

  4. Non-additive and additive genetic effects on extraversion in 3314 Dutch adolescent twins and their parents.

    PubMed

    Rettew, David C; Rebollo-Mesa, Irene; Hudziak, James J; Willemsen, Gonneke; Boomsma, Dorret I

    2008-05-01

    The influence of non-additive genetic influences on personality traits has been increasingly reported in adult populations. Less is known, however, with respect to younger samples. In this study, we examine additive and non-additive genetic contributions to the personality trait of extraversion in 1,689 Dutch twin pairs, 1,505 mothers and 1,637 fathers of the twins. The twins were on average 15.5 years (range 12-18 years). To increase statistical power to detect non-additive genetic influences, data on extraversion were also collected in parents and simultaneously analyzed. Genetic modeling procedures incorporating age as a potential modifier of heritability showed significant influences of additive (20-23%) and non-additive genetic factors (31-33%) in addition to unshared environment (46-48%) for adolescents and for their parents. The additive genetic component was slightly and positively related to age. No significant sex differences were found for either extraversion means or for the magnitude of the genetic and environmental influences. There was no evidence of non-random mating for extraversion in the parental generation. Results show that in addition to additive genetic influences, extraversion in adolescents is influenced by non-additive genetic factors.

  5. Selective neuroinhibitory effects of taurine in slices of rat main olfactory bulb.

    PubMed

    Belluzzi, O; Puopolo, M; Benedusi, M; Kratskin, I

    2004-01-01

    Taurine is abundant in the main olfactory bulb, exceeding glutamate and GABA in concentration. In whole-cell patch-clamp recordings in rat olfactory bulb slices, taurine inhibited principal neurons, mitral and tufted cells. In these cells, taurine decreased the input resistance and caused a shift of the membrane potential toward the chloride equilibrium potential. The taurine actions were sustained under the blockade of transmitter release and were reversible and dose-dependent. At a concentration of 5 mM, typically used in this study, taurine showed 90% of its maximal effect. GABA(A) antagonists, bicuculline and picrotoxin, blocked the taurine actions, whereas the glycine receptor antagonist strychnine and GABA(B) antagonists, CGP 55845A and CGP 35348, were ineffective. These findings are consistent with taurine directly activating GABA(A) receptors and inducing chloride conductance. Taurine had no effect on periglomerular and granule interneurons. The subunit composition of GABA(A) receptors in these cells, differing from those in mitral and tufted cells, may account for taurine insensitivity of the interneurons. Taurine suppressed olfactory nerve-evoked monosynaptic responses of mitral and tufted cells while chloride conductance was blocked. This action was mimicked by the GABA(B) agonist baclofen and abolished by CGP 55845A; CGP 35348, which primarily blocks postsynaptic GABA(B) receptors, was ineffective. The taurine effect most likely was due to GABA(B) receptor-mediated inhibition of presynaptic glutamate release. Neither taurine nor baclofen affected responses of periglomerular cells. The lack of a baclofen effect implies that functional GABA(B) receptors are absent from olfactory nerve terminals that contact periglomerular cells. These results indicate that taurine decreases the excitability of mitral and tufted cells and their responses to olfactory nerve stimulation without influencing periglomerular and granule cells. Selective effects of taurine in the

  6. Radiation processing of thermoplastic starch by blending aromatic additives: Effect of blend composition and radiation parameters

    NASA Astrophysics Data System (ADS)

    Khandal, Dhriti; Mikus, Pierre-Yves; Dole, Patrice; Coqueret, Xavier

    2013-03-01

    This paper reports on the effects of electron beam (EB) irradiation on poly α-1,4-glucose oligomers (maltodextrins) in the presence of water and of various aromatic additives, as model blends for gaining a better understanding at a molecular level the modifications occurring in amorphous starch-lignin blends submitted to ionizing irradiation for improving the properties of this type of bio-based thermoplastic material. A series of aromatic compounds, namely p-methoxy benzyl alcohol, benzene dimethanol, cinnamyl alcohol and some related carboxylic acids namely cinnamic acid, coumaric acid, and ferulic acid, was thus studied for assessing the ability of each additive to counteract chain scission of the polysaccharide and induce interchain covalent linkages. Gel formation in EB-irradiated blends comprising of maltodextrin was shown to be dependent on three main factors: the type of aromatic additive, presence of glycerol, and irradiation dose. The chain scission versus grafting phenomenon as a function of blend composition and dose were studied using Size Exclusion Chromatography by determining the changes in molecular weight distribution (MWD) from Refractive Index (RI) chromatograms and the presence of aromatic grafts onto the maltodextrin chains from UV chromatograms. The occurrence of crosslinking was quantified by gel fraction measurements allowing for ranking the cross-linking efficiency of the additives. When applying the method to destructurized starch blends, gel formation was also shown to be strongly affected by the moisture content of the sample submitted to irradiation. The results demonstrate the possibility to tune the reactivity of tailored blend for minimizing chain degradation and control the degree of cross-linking.

  7. Response to selection in finite locus models with non-additive effects.

    PubMed

    Esfandyari, Hadi; Henryon, Mark; Berg, Peer; Thomasen, Jorn Rind; Bijma, Piter; Sørensen, Anders Christian

    2017-01-12

    Under the finite-locus model in the absence of mutation, the additive genetic variation is expected to decrease when directional selection is acting on a population, according to quantitative-genetic theory. However, some theoretical studies of selection suggest that the level of additive variance can be sustained or even increased when non-additive genetic effects are present. We tested the hypothesis that finite-locus models with both additive and non-additive genetic effects maintain more additive genetic variance (V_A) and realize larger medium-to-long term genetic gains than models with only additive effects when the trait under selection is subject to truncation selection. Four genetic models that included additive, dominance, and additive-by-additive epistatic effects were simulated. The simulated genome for individuals consisted of 25 chromosomes, each with a length of 1M. One hundred bi-allelic QTL, four on each chromosome, were considered. In each generation, 100 sires and 100 dams were mated, producing five progeny per mating. The population was selected for a single trait (h(2)=0.1) for 100 discrete generations with selection on phenotype or BLUP-EBV. V_A decreased with directional truncation selection even in presence of non-additive genetic effects. Non-additive effects influenced long-term response to selection and among genetic models additive gene action had highest response to selection. In addition, in all genetic models, BLUP-EBV resulted in a greater fixation of favourable and unfavourable alleles and higher response than phenotypic selection. In conclusion, for the schemes we simulated, the presence of non-additive genetic effects had little effect in changes of additive variance and V_A decreased by directional selection.

  8. Effect of alloying additions on secondary hardening behavior of Mo-containing steels

    NASA Astrophysics Data System (ADS)

    Kwon, H.; Lee, J. H.; Lee, K. B.; Kim, C. M.; Yang, H. R.

    1997-03-01

    The effect of alloying additions on secondary hardening behavior in Fe-Mo-C steels has been investigated by means of the successive alloying additions of Cr, Co, and Ni. The Cr additions promote M3C cementite formation. The Ni additions destabilize the cementite formation, while the Co additions retard dislocation recovery and present the necessary sites for M2C formation which provides the secondary hardening.

  9. Additive effects of Na+ and Cl- ions on barley growth under salinity stress.

    PubMed

    Tavakkoli, Ehsan; Fatehi, Foad; Coventry, Stewart; Rengasamy, Pichu; McDonald, Glenn K

    2011-03-01

    Soil salinity affects large areas of the world's cultivated land, causing significant reductions in crop yield. Despite the fact that most plants accumulate both sodium (Na(+)) and chloride (Cl(-)) ions in high concentrations in their shoot tissues when grown in saline soils, most research on salt tolerance in annual plants has focused on the toxic effects of Na(+) accumulation. It has previously been suggested that Cl(-) toxicity may also be an important cause of growth reduction in barley plants. Here, the extent to which specific ion toxicities of Na(+) and Cl(-) reduce the growth of barley grown in saline soils is shown under varying salinity treatments using four barley genotypes differing in their salt tolerance in solution and soil-based systems. High Na(+), Cl(-), and NaCl separately reduced the growth of barley, however, the reductions in growth and photosynthesis were greatest under NaCl stress and were mainly additive of the effects of Na(+) and Cl(-) stress. The results demonstrated that Na(+) and Cl(-) exclusion among barley genotypes are independent mechanisms and different genotypes expressed different combinations of the two mechanisms. High concentrations of Na(+) reduced K(+) and Ca(2+) uptake and reduced photosynthesis mainly by reducing stomatal conductance. By comparison, high Cl(-) concentration reduced photosynthetic capacity due to non-stomatal effects: there was chlorophyll degradation, and a reduction in the actual quantum yield of PSII electron transport which was associated with both photochemical quenching and the efficiency of excitation energy capture. The results also showed that there are fundamental differences in salinity responses between soil and solution culture, and that the importance of the different mechanisms of salt damage varies according to the system under which the plants were grown.

  10. Ecotoxicological effects of the antioxidant additive propyl gallate in five aquatic systems.

    PubMed

    Zurita, Jorge L; Jos, Angeles; del Peso, Ana; Salguero, Manuel; López-Artíguez, Miguel; Repetto, Guillermo

    2007-06-01

    Propyl gallate is an antioxidant widely used in foods, cosmetics and pharmaceuticals. The occurrence and fate of additives in the aquatic environment is an emerging issue in environmental chemistry. To date, there is little available information about the adverse effects of propyl gallate on aquatic organisms. Therefore, the toxic effects were investigated, using five model systems from four trophic levels. The most sensitive system was the hepatoma fish cell line PLHC-1 according to total protein content, with an EC(50) of 10 microM and a NOAEL of 1 microM at 72 h, followed by the immobilization of Daphnia magna, the inhibition of bioluminescence of Vibrio fischeri, the salmonid fish cell line RTG-2 and the inhibition of the growth of Chlorella vulgaris. Although protein content, neutral red uptake, methylthiazol metabolization and acetylcholinesterase activity were reduced in PLHC-1 cells, stimulations were observed for lysosomal function, succinate dehydrogenase, glucose-6-phosphate dehydrogenase and ethoxyresorufin-O-deethylase activities. No changes were observed in metallothionein levels. The main morphological observations were the loss of cells and the induction of cell death mainly by necrosis but also by apoptosis. The protective and toxic effects of propyl gallate were evaluated. General antioxidants and calcium chelators did not modify the toxicity of propyl gallate, but an iron-dependent lipid peroxidation inhibitor gave 22% protection. The results also suggest that propyl gallate cytotoxicity is dependent on glutathione levels, which were modulated by malic acid diethyl ester and 2-oxothiazolidine-4-carboxylic acid. According to the results, propyl gallate should be classified as toxic to aquatic organisms.

  11. Long-term effects of precommercial thinning on small mammals in northern Maine

    USGS Publications Warehouse

    Homyack, J.A.; Harrison, D.J.; Krohn, W.B.

    2005-01-01

    Precommercial thinning (PCT) is being practiced increasingly throughout the Acadian forest of eastern North America to meet silvicultural objectives; however, effects of this practice on wildlife, both immediately and several years post-treatment are not well understood. Forest dependent small mammals have ecological roles as prey for numerous avian and mammalian predators, dispersers of seeds, fruit, and spores, and contribute to nutrient cycling. Researchers in the northwestern USA have suggested that thinning of young, regenerating clearcuts may increase the abundance and diversity of some forest-dependent small mammals by increasing rates of forest development and enhancing the ecological representation of mid-successional stands across managed landscapes. We examined the effects of PCT within conifer-dominated forest stands 1-, 6-, 11-, and 16-years post-treatment, on abundances of mice, voles, and shrews, and on within-stand structure in the commercially managed, Acadian forests of northern Maine. We live-trapped small mammals on 24 herbicide-treated clearcuts treated with PCT and on 13 similar, unthinned stands during summers of 2000 and 2001. Thinning of mid-successional conifer stands resulted in increased abundances, (red-backed voles, Clethrionomys gapperi, P = 0.008; masked shrews, Sorex cinereus, P < 0.001) or had no detectable effect on (deer mice, Peromyscus maniculatus, P = 0.544; short-tailed shrews, Blarina brevicauda, P = 0.517) the 4 most common species of Muridae and Soricidae in northern Maine. In general, abundance of deer mice responded more positively to increasing development class and to the number of years since thinning than other species of small mammals. Several within-stand habitat characteristics associated with stand maturity, such as larger stem diameters and a partially open canopy, occurred in thinned stands. Thus, PCT may accelerate the development of habitat attributes typical of mid-successional conifer stands in intensively

  12. Effect of LA on the Growth and Development of the Main Organs in Female Mice.

    PubMed

    He, Xiuyuan; Lin, Feng; Li, Yongtao; Chen, Yuxia; Li, Jing; Guo, Linlin; Han, Xuelei; Song, Huan

    2017-01-01

    Effects of lead acetate (LA) on the growth and development of major organs in female mice were studied. Female mice were divided randomly into four treatment groups and one control group. In treatment groups, mice were injected with different concentrations of LA solution every 2 days; whereas control-group mice received equal volumes of sterile normal saline. Body weight (BW) and symptoms were recorded every 2 days. After LA exposure, mice were executed by cervical dislocation and main organs (heart, liver, spleen, lung, kidney) collected for evaluation of morphologic and histologic changes. LA could greatly affect increases in BW, and BW decreased with increasing dose and time of exposure to LA. Compared with the control group, organ coefficients in treatment groups were of the order kidney and spleen > liver and lung > heart and demonstrated obvious dose-time effects. LA exposure could damage the heart, liver, spleen, lung, and kidney. Damage to the kidney and spleen was the most severe, followed by that to the liver, heart, and lung. Damage was aggravated with increasing doses and exposure time to LA in an obvious dose-time relationship; when LA dose was ≥20 mg/kg, the growth and development of mice were obviously inhibited. These results suggest that long-term exposure to low-dose LA can result in universal pathologic damage to mouse organs and that severity is dependent on the dose and duration of LA exposure.

  13. Effect of Dreissena mussels on the distribution of zooplankton as exemplified by the Main Kakhovka Canal

    SciTech Connect

    Grigorovich, I.A.; Shevtsova, L.V.

    1995-06-01

    In summer the abundance of zooplankton in the Main Kakhovka Canal varied in the range of 1,500-18,500 indiv.m{sup -3}, with a biomass of 15-240 mg m{sup -3}. From the upper reach of the canal to the end, the zooplankton become less diverse and there is a decrease in both abundance and biomass. In the initial sections of the canal, copepods predominated, owing to their considerable influxes from other sources, i.e., Kakhovka Reservoir. Whereas in the second half of the canal, the dominant complexes of zooplankton changed and consisted primarily of cladocerans and Dreissena veligers. With high abundance of Dreissena polymorpha (Pallas) and D. bugensis (Andrusov) (mean biomass was 4.2 kg m{sup -2}), with the maximum ca. 17.8 kg m{sup -2}, mussels had a significant effect on the spatial distribution of planktonic invertebrates. In different areas of the canal the measurable quantitive replenishment of zooplankton was proceeded by planktonic larvae of Dreissena. Being active filterers, Dreissena mollusks undermine food resources of filter-feeding zooplankton by accelerating sedimentation of suspended matter, including organic substances, by a factor of 1.4-3.0. Dreissena can control zooplankton density by consumption of some of the species. With predominating rotifers and juveniles cladocerans in the plankton, the total abundance of zooplankton influenced by Dreissena bugensis had decreased by 53% after 12 h, whereas the amount of dominant species, Euchlanis dilatata and Bosmina longirostris, had declined respectively by 92% and 64%. Dreissena individuals 14-18 mm long, are the predominant size group of mussels in the Main Kakhovka Canal and can filter off planktonic invertebrates with body lengths between 20 and 400 m. Zooplankton species of such size can pass through the bronchial siphon of Dreissena and so they are vulnerable to consumption by mussels. There is an inverse relationship between the biomass of zooplankton and the biomass of adult Dreissena mussels.

  14. Determining the Effects of EMIC Waves on Precipitating MeV Electrons during Strom Main Phases

    NASA Astrophysics Data System (ADS)

    Chen, Y.

    2015-12-01

    Theoretic studies have suggested that electromagnetic ion cyclotron (EMIC) waves can cause significant precipitation of ~MeV electrons, supposedly accounting for the fast dropouts of outer-belt electrons during storm main phases. Usually the resonance between left-hand polarized EMIC with electrons with moderate energy is unlikely due to their opposite polarizations, while resonance with highly relativistic electrons do occur and cause electrons to precipitate into the atmosphere through pitch-angle scattering. Several previous studies on observations find a close relation between the two phenomena, e.g., Cliverd et al. [2007], Sandanger et al. [2007], and Miyoshi et al. [2008], while others find otherwise, e.g., Meredith et al. [2011]; recently, more observational evidence supporting the connection has been reported (e.g., Li et al. [2014] and Blum et al. [2015]). However, whether and under what favoring conditions EMIC waves cause rapid dropouts of relativistic electrons during storm main phases remain unresolved questions. Here, using latest wave and electron data from multiple missions including Van Allen Probes, BARREL, and NOAA POES, we systemically examine the relation between EMIC waves and MeV electron precipitation. We first construct two independent event lists for intensified EMIC waves and enhancements of MeV electron precipitation, respectively. Then we cross check the two lists to identify if any significant correlation exists in between, and further characterize the wave effectiveness in terms of L-shell, MLT, resonance energy, as well as the background plasma conditions. Results from this study will advance our knowledge about the loss mechanism of outer-belt electrons, thus laying down another stepping stone towards high-fidelity physics-based models for radiation belts.

  15. Breakage and re-growth of flocs: effect of additional doses of coagulant species.

    PubMed

    Yu, Wenzheng; Gregory, John; Campos, Luiza C

    2011-12-15

    Several polyaluminum chloride (PACl) coagulants were prepared, with different OH/Al ratios (B values), and characterized by Ferron assay. These were used in studies of floc formation, breakage and re-growth with kaolin suspensions under controlled shear conditions, using a continuous optical monitoring method. Particular attention was paid to the effect of small additional coagulant dosages, added during the floc breakage period, on the re-growth of broken flocs. The results showed that the re-growth ability was greatly dependent on the nature of the PACl species added as second coagulant. The re-growth ability of broken flocs was greatest when the second coagulant was PACl(0) (i.e. AlCl(3), with B = 0) and least with PACl(25) (B = 2.5). In the latter case there was no effect on floc re-growth, irrespective of the initial coagulant used. PACls with intermediate B values gave some improvement in floc re-growth, but less than that with PACl(0). Additional dosage of PACl(0) gave re-grown flocs about the same size or even larger than those before breakage. The re-growth of broken flocs is significantly correlated with the species Al(a) (monomeric) and Al(b) (polymeric), as determined by Ferron assay. The amorphous hydroxide precipitate formed from PACl(0), (mainly Al(a)) can greatly improve the adhesion between broken flocs and give complete re-growth. However, for PACl(25), mostly composed of Al(b), the nature of the precipitate is different and there is no effect on floc re-growth.

  16. Effect of nano-additives on microstructure, mechanical properties and wear behaviour of Fe⿿Cr⿿B hardfacing alloy

    NASA Astrophysics Data System (ADS)

    Gou, Junfeng; Lu, Pengpeng; Wang, You; Liu, Saiyue; Zou, Zhiwei

    2016-01-01

    Fe⿿Cr⿿B hardfacing alloys with different nano-additives content were investigated. The effects of nano-additives on the microstructures of hardfacing alloy were studied by using optical microscope, scanning electron microscope, X-ray diffractometer. The hardness and the fracture toughness of hardfacing alloys were measured, respectively. The sliding wear tests were carried out using a ball-on-disc tribometer. The experimental results showed that primary carbide of hardfacing alloys was refined and its distribution became uniform with content of nano-additives increased. The hardfacing alloys are composed of Cr7C3, Fe7C3, α-Fe and Fe2B according to the results of X-ray diffraction. The hardness of hardfacing alloys increased linearly with the increase of nano-additives. The hardness of the hardfacing alloy with 1.5 wt.% nano-additives increased 54.8% than that of the hardfacing alloy without nano-additives and reached to 1011HV. The KIC of the hardfacing alloy with 0.65 wt.% nano-additives was 15.4 MPam1/2, which reached a maximum. The value increased 57.1% than that of the hardfacing alloy without nano-additives. The wear rates of the hardfacing layer with 0.65 wt.% and 1.0 wt.% nano-additives decreased about 88% than that of the hardfacing layer without nano-additives. The main wear mechanism was adhesion wear.

  17. Main Report

    PubMed Central

    2006-01-01

    -specific recommendations. On the basis of this information, conditions were assigned to one of three categories as described above:Core Panel;Secondary Targets (conditions that are part of the differential diagnosis of a core panel condition.); andNot Appropriate for Newborn Screening (either no newborn screening test is available or there is poor performance with regard to multiple other evaluation criteria). ACMG also considered features of optimal newborn screening programs beyond the tests themselves by assessing the degree to which programs met certain goals (e.g., availability of educational programs, proportions of newborns screened and followed up). Assessments were based on the input of experts serving in various capacities in newborn screening programs and on 2002 data provided by the programs of the National Newborn Screening and Genetics Resource Center (NNSGRC). In addition, a brief cost-effectiveness assessment of newborn screening was conducted. Results: Uniform panel A total of 292 individuals determined to be generally representative of the regional distribution of the United States population and of areas of expertise or involvement in newborn screening provided a total of 3,949 evaluations of 84 conditions. For each condition, the responses of at least three experts in that condition were compared with those of all respondents for that condition and found to be consistent. A score of 1,200 on the data collection instrument provided a logical separation point between high scoring conditions (1,200–1,799 of a possible 2,100) and low scoring (<1,000) conditions. A group of conditions with intermediate scores (1,000–1,199) was identified, all of which were part of the differential diagnosis of a high scoring condition or apparent in the result of the multiplex assay. Some are identified by screening laboratories and others by diagnostic laboratories. This group was designated as a “secondary target” category for which the program must report the diagnostic result

  18. Effects of the main extraction parameters on chemical and microbial characteristics of compost tea.

    PubMed

    Islam, M K; Yaseen, T; Traversa, A; Ben Kheder, M; Brunetti, G; Cocozza, C

    2016-06-01

    The rising popularity of compost tea as fertilizer or foliar spray against pathogens has encouraged many researchers to evaluate its performance without standardizing its quality, so obtaining inconsistent and controversial results. The fertilizing and pesticide-like effects of compost tea are due to its chemical and microbiological properties. Therefore, this study aimed to identify the best combination of the compost tea extraction parameters for exalting both chemical and microbiological features. A factorial design was adopted to evaluate the effects of compost/water ratio, extraction time, storage duration and storage temperature in different combination on physical, chemical and microbiological characteristics of compost tea, and the results were elaborated through different statistical analyses. Compost tea nutrients and microorganisms were influenced by compost/water ratio and extraction time. In addition, the storage duration affected the microbial populations, whereas the storage temperature influenced only the fungal population of compost tea. Results suggested that the best combination of the studied parameters was: 1:2.5 compost/water ratio, 2days of extraction time and the compost tea should be utilized immediately after the extraction, since the storage reduced the microbial populations.

  19. THE EFFECT OF SEED TREATMENT ON THE MAIN PATHOGENS PRESENT IN WHEAT AGROECOSYSTEMS.

    PubMed

    Stef, R; Grozea, I; Puia, C; Carabet, A; Vlad, M; Manea, D

    2014-01-01

    Wheat crop (Triticum aestivum L.) from Poaceae family is affected by many diseases that cause yield losses. The present paper addresses a topic of economic, agrotechnics and social importance of wheat crop (occupying the first place among the Romanian cultivated crop, feeding 35 to 40% of world population). The study had as main objective product testing like Yunta 246 FS (imidacloprid 233 g/l + tebuconazol 13 g/l), Team Micorriza Plus (Glomus intraradices 150 spore/g + Glomus mosseae 150 spore/g + organic matter 56% and Rhizosphere Bacteria 107 UFC/g) and Condor (Trichoderma spp. 1 x 109 spore/g + Glomus sp. 10 spore/g + Rhizosphere Bacteria 1 x 107 UFC/g and organic matter 7%) applied in the pathosystem wheat/pathogens. The research was conducted in the western part of Romania, in 2010-2012, experience was placed after Latin rectangle method with 10 variants (they are different by product and dose applied) and the data were statistically interpreted. Results showed the presence of pathogens Septoria tritici, Drechslera tritici repentis and Drechslera teres in experimental variants. Statistical analysis showed that the most effective chemical mixture was imidacloprid + tebuconazol at the highest dose tested (3 l/t). Regarding the non-chemical product testing, the product Condor gave positive results. The highest values of quality parameters (protein and gluten) were obtained in the variants treated with Yunta 246 FS.

  20. The effect of runway surface and braking on Shuttle Orbiter main gear tire wear

    NASA Technical Reports Server (NTRS)

    Daugherty, Robert H.; Stubbs, Sandy M.

    1992-01-01

    In 1988, a 1067 m long touchdown zone on each end of the Kennedy Space Center (KSC) Shuttle Landing Facility (SLF) was modified from its original heavy-broom finish with transverse grooves configuration to a longitudinal corduroy surface texture with no transverse grooves. The intent of this modification was to reduce the spin-up wear on the Orbiter main gear tires and provide for somewhat higher crosswind capabilities at that site. The modification worked well, so it was proposed that the remainder of the runway be modified as well to permit even higher crosswind landing capability. Tests were conducted at the NASA Langley Aircraft Landing Dynamics Facility (ALDF) to evaluate the merit of such a modification. This paper discusses the results of these tests, and explains why the proposed modification did not provide the expected improvement and thus was not implemented. Also, in an ongoing program to evaluate the origin of various tire wear phenomenon, a series of tests was conducted to evaluate the effect of braking on tire wear. Finally, a modified tire is discussed in terms of its wear performance under rollout and braking operations.

  1. Trust and team performance: A meta-analysis of main effects, moderators, and covariates.

    PubMed

    De Jong, Bart A; Dirks, Kurt T; Gillespie, Nicole

    2016-08-01

    Cumulating evidence from 112 independent studies (N = 7,763 teams), we meta-analytically examine the fundamental questions of whether intrateam trust is positively related to team performance, and the conditions under which it is particularly important. We address these questions by analyzing the overall trust-performance relationship, assessing the robustness of this relationship by controlling for other relevant predictors and covariates, and examining how the strength of this relationship varies as a function of several moderating factors. Our findings confirm that intrateam trust is positively related to team performance, and has an above-average impact (ρ = .30). The covariate analyses show that this relationship holds after controlling for team trust in leader and past team performance, and across dimensions of trust (i.e., cognitive and affective). The moderator analyses indicate that the trust-performance relationship is contingent upon the level of task interdependence, authority differentiation, and skill differentiation in teams. Finally, we conducted preliminary analyses on several emerging issues in the literature regarding the conceptualization and measurement of trust and team performance (i.e., referent of intrateam trust, dimension of performance, performance objectivity). Together, our findings contribute to the literature by helping to (a) integrate the field of intrateam trust research, (b) resolve mixed findings regarding the trust-performance relationship, (c) overcome scholarly skepticism regarding the main effect of trust on team performance, and (d) identify the conditions under which trust is most important for team performance. (PsycINFO Database Record

  2. Antispasmodic effects of Prangos ferulacea acetone extract and its main component osthole on ileum contraction

    PubMed Central

    Sadraei, H; Shokoohinia, Y; Sajjadi, S E; Mozafari, M

    2013-01-01

    Prangos ferulacea is a plant found in the Mediterranean and Middle-east regions used as carminative, anti-flatulent, emollient and antibacterial herb. It is believed that the coumarins are responsible for some of known effects of Prangos. In this research the relaxant effects of P. ferulacea coumrin rich extract as well as osthole as its main prenylated coumarins were investigated on rat ileum contraction in vitro. Relaxant effect of osthole and P. ferulacea extract were examined on contraction induced by KCl, acetylcholine (ACh) and electrical field stimulation (EFS) and compared with propantheline and nifedipine. The acetone extract of P. ferulacea concentration-dependently relaxed ileum contraction induced by KCl (IC50=1.3 ± 0.25 μg/ml), ACh (IC50=7.7 ± 1.1 μg/ml) and EFS (IC50=8.8 ± 1.4 μg/ml), while, the extract at lower concentration (4 μg/ml) potentiated the ACh and EFS responses. Unlike the extract, osthole did not potentiate the ileum contraction but concentration-dependently inhibited ileum contractile responses to KCl (IC50=2.2 ± 0.7 μg/ml), ACh (IC50=2.5 ± 0.7 μg/ml) and EFS (IC50=2.8 ± 0.24 μg/ml). Propantheline concentration dependently inhibited the ileum response to ACh, with IC50 value of 0.61 ± 0.09nM without affecting the KCl response. As expected, the EFS response was only partially reduced. Nifedipine (0.2-50 nM) inhibited tonic contraction induced by KCl with IC50 value of 2.5 ± 0.8 nM but only partially inhibited the response to ACh. However, the response to EFS was reduced only by 33%. These results confirmed both potentiatory and inhibitory action of P. ferulacea extract on rat ileum contractile activity. Osthole is responsible for the inhibitory effect but potentiating components are not yet known. PMID:24019823

  3. Effects of Zr Additions on the Microstructure and Impression Creep Behavior of AZ91 Magnesium Alloy

    NASA Astrophysics Data System (ADS)

    Kabirian, F.; Mahmudi, R.

    2010-12-01

    The effects of 0.2, 0.6, and 1.0 wt pct Zr additions on the microstructure and creep behavior of AZ91 Mg alloy were investigated by impression tests carried out under constant punching stress ( σ imp) in the range 100 to 650 MPa, corresponding to the modulus-compensated stress levels of {{0.007 le σ_{{imp}} } {G le 0.044}} , at temperatures in the range 425 K to 570 K (152 °C to 297 °C). The alloy containing 0.6 wt pct Zr showed the best creep resistance mainly due to the favorable formation of Al3Zr2 and Al2Zr intermetallic compounds, reduction in the volume fraction of the eutectic β-Mg17Al12 phase, and solid solution hardening effects of Al in the Mg matrix. Based on the obtained stress exponents of 4.2 to 6.5 and activation energies of 90.7 to 127.1 kJ/mol, it is proposed that two parallel mechanisms of lattice and pipe-diffusion-controlled dislocation climb compete. Dislocation climb controlled by dislocation pipe diffusion prevails at high stresses, whereas climb of edge dislocations is the controlling mechanism at low stresses.

  4. Efficiently and Effectively Evaluating Public Service Announcements: Additional Evidence for the Utility of Perceived Effectiveness.

    PubMed

    Bigsby, Elisabeth; Cappella, Joseph N; Seitz, Holli H

    2013-03-01

    Recent research has made significant progress identifying measures of the perceived effectiveness (PE) of persuasive messages and providing evidence of a causal link from PE to actual effectiveness (AE). This article provides additional evidence of the utility of PE through unique analysis and consideration of another dimension of PE important to understanding the PE-AE association. Current smokers (N =1,139) watched four randomly selected anti-smoking Public Service Announcements (PSAs). PE scores aggregated by message were used instead of individual PE scores to create a summed total, minimizing the likelihood that PE perceptions are consequences of an individual's intention to quit, supporting instead the PE→AE order. Linear regression analyses provide evidence of PE's positive and significant influence on smoking cessation-related behavioral intentions.

  5. Efficiently and Effectively Evaluating Public Service Announcements: Additional Evidence for the Utility of Perceived Effectiveness

    PubMed Central

    Bigsby, Elisabeth; Cappella, Joseph N.; Seitz, Holli H.

    2014-01-01

    Recent research has made significant progress identifying measures of the perceived effectiveness (PE) of persuasive messages and providing evidence of a causal link from PE to actual effectiveness (AE). This article provides additional evidence of the utility of PE through unique analysis and consideration of another dimension of PE important to understanding the PE-AE association. Current smokers (N =1,139) watched four randomly selected anti-smoking Public Service Announcements (PSAs). PE scores aggregated by message were used instead of individual PE scores to create a summed total, minimizing the likelihood that PE perceptions are consequences of an individual’s intention to quit, supporting instead the PE→AE order. Linear regression analyses provide evidence of PE’s positive and significant influence on smoking cessation-related behavioral intentions. PMID:25568588

  6. Modulation of Additive and Interactive Effects in Lexical Decision by Trial History

    ERIC Educational Resources Information Center

    Masson, Michael E. J.; Kliegl, Reinhold

    2013-01-01

    Additive and interactive effects of word frequency, stimulus quality, and semantic priming have been used to test theoretical claims about the cognitive architecture of word-reading processes. Additive effects among these factors have been taken as evidence for discrete-stage models of word reading. We present evidence from linear mixed-model…

  7. Effects of late holocene forest disturbance and vegetation change on acidic mud pond, Maine, USA

    SciTech Connect

    Rhodes, T.E.; Davis, R.B.

    1995-04-01

    The limnological effects of natural forest disturbance and succession were studied by analyzing the chemistry, charcoal, pollen, chrysophytes, and diatoms in sediments deposited from {approx}3500 to {approx}700 yr BP in Mud Pond, Maine. Fine-grained sediments rich in organic matter are interrupted every 100-500 yr ({bar X} = 280) by coarser, more minerogenic sediments, reflecting soil erosion. The disturbance horizons contain high concentrations of charcoal, indicating forest fires, low percentages of pollen of late-successional trees such as Tsuga, and high percentages of pollen and spores of early-successional plants such as shrubs and ferns. Within a few decades, pollen percentages of Alnus peak, followed by Betula. Tsuga pollen percentages increase for 200-400 yr after disturbances, and generally stabilize or decrease several decades before the next disturbance. Limnological responses to these changes are indicated by high percentages of diatoms and chrysophytes of waters of near neutral pH. Diatom-inferred pH typically increases abruptly from {approx}5.0 to {approx}6.1, and chrysophyte-inferred pH from {approx}5.5 to {approx}5.8 at disturbance horizons. These increases may be caused by increased wood ash and mineral soils after disturbances. This pulse is followed by a two-step recovery. First the inferred pH decreases nearly to the pre-disturbance condition. This response likely results from soil stabilization and uptake of base cations by successional vegetation. Second, a slower acidification of {approx}0.1 pH unit per century occurs as early successional shrubs and hardwood forest are replaced by old-growth conifer forest. Increasing percentages of pollen of Picea, Alnus, and Salix by 1350 yr BP, and decreasing percentages of hemlock and beech around 1350 yr BP imply cooler conditions. Large changes in diatom and chrysophyte assemblages in approximately this period may be related. 64 refs., 8 figs., 3 tabs.

  8. Meselect – A Rapid and Effective Method for the Separation of the Main Leaf Tissue Types

    PubMed Central

    Svozil, Julia; Gruissem, Wilhelm; Baerenfaller, Katja

    2016-01-01

    Individual tissues of complex eukaryotic organisms have specific gene expression programs that control their functions. Therefore, tissue-specific molecular information is required to increase our understanding of tissue-specific processes. Established methods in plants to obtain specific tissues or cell types from their organ or tissue context typically require the enzymatic degradation of cell walls followed by fluorescence-activated cell sorting (FACS) using plants engineered for localized expression of green fluorescent protein. This has facilitated the acquisition of valuable data, mainly on root cell type-specific transcript and protein expression. However, FACS of different leaf cell types is difficult because of chlorophyll autofluorescence that interferes with the sorting process. Furthermore, the cell wall composition is different in each cell type. This results in long incubation times for refractory cell types, and cell sorting itself can take several hours. To overcome these limitations, we developed Meselect (mechanical separation of leaf compound tissues), a rapid and effective method for the separation of leaf epidermal, vascular and mesophyll tissues. Meselect is a novel combination of mechanical separation and rapid protoplasting, which benefits from the unique cell wall composition of the different tissue types. Meselect has several advantages over cell sorting: it does not require expensive equipment such as a cell sorter and does not depend on specific fluorescent reporter lines, the use of blenders as well as the inherent mixing of different cell types and of intact and damaged cells can be avoided, and the time between wounding of the leaf and freezing of the sample is short. The efficacy and specificity of the method to enrich the different leaf tissue types has been confirmed using Arabidopsis leaves, but it has also been successfully used for leaves of other plants such as tomato or cassava. The method is therefore useful for plant

  9. Meselect - A Rapid and Effective Method for the Separation of the Main Leaf Tissue Types.

    PubMed

    Svozil, Julia; Gruissem, Wilhelm; Baerenfaller, Katja

    2016-01-01

    Individual tissues of complex eukaryotic organisms have specific gene expression programs that control their functions. Therefore, tissue-specific molecular information is required to increase our understanding of tissue-specific processes. Established methods in plants to obtain specific tissues or cell types from their organ or tissue context typically require the enzymatic degradation of cell walls followed by fluorescence-activated cell sorting (FACS) using plants engineered for localized expression of green fluorescent protein. This has facilitated the acquisition of valuable data, mainly on root cell type-specific transcript and protein expression. However, FACS of different leaf cell types is difficult because of chlorophyll autofluorescence that interferes with the sorting process. Furthermore, the cell wall composition is different in each cell type. This results in long incubation times for refractory cell types, and cell sorting itself can take several hours. To overcome these limitations, we developed Meselect (mechanical separation of leaf compound tissues), a rapid and effective method for the separation of leaf epidermal, vascular and mesophyll tissues. Meselect is a novel combination of mechanical separation and rapid protoplasting, which benefits from the unique cell wall composition of the different tissue types. Meselect has several advantages over cell sorting: it does not require expensive equipment such as a cell sorter and does not depend on specific fluorescent reporter lines, the use of blenders as well as the inherent mixing of different cell types and of intact and damaged cells can be avoided, and the time between wounding of the leaf and freezing of the sample is short. The efficacy and specificity of the method to enrich the different leaf tissue types has been confirmed using Arabidopsis leaves, but it has also been successfully used for leaves of other plants such as tomato or cassava. The method is therefore useful for plant

  10. Tramadol: Effects on sexual behavior in male rats are mainly caused by its 5-HT reuptake blocking effects.

    PubMed

    Olivier, Jocelien D A; Esquivel Franco, Diana C; Oosting, Ronald; Waldinger, Marcel; Sarnyai, Zoltan; Olivier, Berend

    2016-11-24

    Tramadol is a well-known and effective analgesic. Recently it was shown that tramadol is also effective in human premature ejaculation. The inhibitory effect of tramadol on the ejaculation latency is probably due to its mechanism of action as a μ-opioid receptor agonist and noradrenaline/serotonin (5-HT) reuptake inhibitor. In order to test this speculation, we tested several doses of tramadol in a rat model of male sexual behavior and investigated two types of drugs interfering with the μ-opioid and the 5-HT system. First the μ-opioid receptor agonist properties of tramadol were tested with naloxone, a μ-opioid receptor antagonist. Second, the effects of WAY100,635, a 5-HT1A receptor antagonist, were tested on the behavioral effects of tramadol. Finally the effects of paroxetine, a selective serotonin reuptake inhibitor, combined with naloxone or WAY100,635 treatment, were compared to the effects of tramadol combined with these drugs. Results showed that naloxone, at a sexually inactive dose, could only partially antagonize the inhibitory effect of tramadol. Moreover, low and behaviorally inactive doses of WAY100,635, strongly decreased sexual behavior when combined with a behaviorally inactive dose of tramadol. Finally we showed that the effects of paroxetine on sexual behavior resembled the effects of tramadol, indicating that tramadol's inhibitory effects on sexual behavior are primarily and mainly caused by its SSRI properties and that its μ-opioid receptor agonistic activity only contributes marginally. These findings support the hypothesis that tramadol exerts inhibition of premature ejaculations in men by its 5-HT reuptake inhibiting properties.

  11. The Effect of Acoustic Disturbances on the Operation of the Space Shuttle Main Engine Fuel Flowmeter

    NASA Technical Reports Server (NTRS)

    Marcu, Bogdan; Szabo, Roland; Dorney, Dan; Zoladz, Tom

    2007-01-01

    The Space Shuttle Main Engine (SSME) uses a turbine fuel flowmeter (FFM) in its Low Pressure Fuel Duct (LPFD) to measure liquid hydrogen flowrates during engine operation. The flowmeter is required to provide accurate and robust measurements of flow rates ranging from 10000 to 18000 GPM in an environment contaminated by duct vibration and duct internal acoustic disturbances. Errors exceeding 0.5% can have a significant impact on engine operation and mission completion. The accuracy of each sensor is monitored during hot-fire engine tests on the ground. Flow meters which do not meet requirements are not flown. Among other parameters, the device is screened for a specific behavior in which a small shift in the flow rate reading is registered during a period in which the actual fuel flow as measured by a facility meter does not change. Such behavior has been observed over the years for specific builds of the FFM and must be avoided or limited in magnitude in flight. Various analyses of the recorded data have been made prior to this report in an effort to understand the cause of the phenomenon; however, no conclusive cause for the shift in the instrument behavior has been found. The present report proposes an explanation of the phenomenon based on interactions between acoustic pressure disturbances in the duct and the wakes produced by the FFM flow straightener. Physical insight into the effects of acoustic plane wave disturbances was obtained using a simple analytical model. Based on that model, a series of three-dimensional unsteady viscous flow computational fluid dynamics (CFD) simulations were performed using the MSFC PHANTOM turbomachinery code. The code was customized to allow the FFM rotor speed to change at every time step according to the instantaneous fluid forces on the rotor, that, in turn, are affected by acoustic plane pressure waves propagating through the device. The results of the simulations show the variation in the rotation rate of the flowmeter

  12. Non-additive effects of litter diversity on greenhouse gas emissions from alpine steppe soil in Northern Tibet.

    PubMed

    Chen, Youchao; Sun, Jian; Xie, Fangting; Yan, Yan; Wang, Xiaodan; Cheng, Genwei; Lu, Xuyang

    2015-12-04

    While litter decomposition is a fundamental ecological process, previous studies have mainly focused on the decay of single species. In this study, we conducted a litter-mixing experiment to investigate litter diversity effects on greenhouse gas (GHG) emissions from an alpine steppe soil in Northern Tibet. Significant non-additive effects of litter diversity on GHG dynamics can be detected; these non-additive effects were the result of species composition rather than species richness. Synergistic effects were frequent for CO2 and N2O emissions, as they were found to occur in 70.5% and 47.1% of total cases, respectively; antagonistic effects on CH4 uptake predominated in 60.3% of the cases examined. The degree of synergism and antagonism may be significantly impacted by litter chemical traits, such as lignin and N, lignin:N ratio, and total phenols during decomposition (P < 0.05). In addition, the relationship between chemical traits and litter-mixing effects changed over incubation time. Our study provides an opportunity to gain insight into the relationship between litter diversity and soil ecological processes. The results indicate that higher plant diversity may generally enhance CO2 and N2O emissions while inhibiting CH4 uptake; meanwhile, the direction and strength of non-additive effects appear to be related to litter chemical traits.

  13. Effect of additives on jet fuel thermal stability determined using the gravimetric JFTOT

    SciTech Connect

    Pande, S.G.; Hardy, D.R.

    1996-10-01

    In an effort to address the need for improving the thermal stabilities of jet fuels, various additives are being examined. These include the antioxidant, BHT; a metal deactivator, MDA (N,N{prime}-Disalicylidene-1,2-propane diamine); a combination of BHT and MDA; and two dispersant/detergent additives, viz., a Betz and Mobil additive. In general, the additives were screened in three test fuels, viz., a refinery sampling blend (RSB), a JP-8, and a Jet A. Additive effectiveness on aging a fuel in the presence of 400 ppb copper was examined in the RSB fuel. Based on the studies conducted, the most effective additives were the MDA/BHT combination, the Betz, and the Mobil additive (when tested). For example, these additives significantly lowered the total thermal deposits formed for the copper-doped aged fuel. For the remaining two test fuels, differentiation in effectiveness among the additives screened was considerably less. These results, which are likely due to the test fuels being relatively thermally stable, focus on the necessity of using less stable fuels to better differentiate additive effectiveness.

  14. Effect of different oxytetracycline addition methods on its degradation behavior in soil.

    PubMed

    Chen, Gui-Xiu; He, Wei-Wei; Wang, Yan; Zou, Yong-De; Liang, Juan-Boo; Liao, Xin-Di; Wu, Yin-Bao

    2014-05-01

    The degradation behavior of veterinary antibiotics in soil is commonly studied using the following methods of adding antibiotics to the soil: (i) adding manure collected from animals fed with a diet containing antibiotics, (ii) adding antibiotic-free animal manure spiked with antibiotics and (iii) directly adding antibiotics. No research simultaneously comparing different antibiotic addition methods was found. Oxytetracycline (OTC) was used as a model antibiotic to compare the effect of the three commonly used antibiotic addition methods on OTC degradation behavior in soil. The three treatment methods have similar trends, though OTC degradation half-lives show the following significant differences (P<0.05): manure from swine fed OTC (treatment A)main entry route for veterinary antibiotics into soil is via the manure of animals given with antibiotics, the most appropriate method to study the degradation and ecotoxicity of antibiotic residues in soil may be to use manure from animals that are given a particular antibiotic, rather than by adding it directly to the soil.

  15. Fractions of Rechtschaffner matrices as supersaturated designs in screening experiments aimed at evaluating main and two-factor interaction effects.

    PubMed

    Cela, R; Phan-Tan-Luu, R; Claeys-Bruno, M; Sergent, M

    2012-04-06

    Optimal fractions of resolution V design matrices proposed by Rechtschaffner in 1967 are developed and applied as supersaturated designs in screening experiments. Rechtschaffner matrices allow evaluation of all main factors and two-factor interactions, which in many real-world studies are of practical significance. However, the number of experimental runs increases rapidly with the number of factors in the matrices, which are therefore impractical for more than 5-6 factors. On the contrary, saturated fractions based on Hadamard matrices, which are commonly applied in screening studies, cannot evaluate the interaction effects. Here, a procedure for selecting the optimum fractions of Rechtschaffner matrices is presented and provides supersaturated matrices that are well adapted to a variety of problems, thus allowing the development of screening studies with a relatively small number of experiments. The procedures developed to derive the size-reduced matrices and to evaluate the active factors are discussed and compared in terms of efficiency and reliability, by means of simulation studies and application to a real problem. These fractions are the first supersaturated design matrices capable of estimating interaction effects. Additionally, one important advantage of these supersaturated matrices is that they enable development of follow-up procedures in cases of inconclusive results, by enlarging the matrix and eventually resolving the full Rechtschaffner matrix of departure when it is necessary to evaluate the active factors and their interactions.

  16. Effect of two natural light regimes and nutrient addition on the forest herb Begonia decandra (Begoniaceae).

    PubMed

    Cordero, R A

    2000-01-01

    The effect of two natural light-growing conditions (understory versus light gaps) and the interaction with nutrient availability (through fertilization) were studied in the understory herb Begonia decandra, in the Luquillo Experimental Forest in Puerto Rico. Sixteen potted plants obtained from cuttings were randomly chosen and distributed in each of eighth forest environments (four light gaps and four understories), for a total of 128 plants. Fertilizer was applied to half of the plants in each site. After seven months in the two given microenvironments, increased light and fertilization resulted in greater growth and some changes in the biomass allocation patterns. All measured variables responded similarly to reported changes for tree seedlings and saplings from other tropical and subtropical regions. Total growth parameters (height, biomass and leaf area) were very sensitive to increases in the main resource (light). The addition of nutrients was less important in producing changes in the allocation variables (root to shoot ratio, leaf area ratio, and specific leaf mass) under conditions of high light availability. Changes due to nutrient levels were relatively greater on plants grown under under-story conditions. Also, small light differences among sites can cause significant changes in the variables related to total growth. Lastly, plant mortality in the nutrient treatments was found to be independent of mortality in two forest light environments. Some hypotheses about resource acquisition and plant growth are not supported by this data.

  17. Effect of Oxygen-affinity Additives on the Superconducting Properties of Magnesium Diboride

    NASA Astrophysics Data System (ADS)

    Jang, J.-J.; Ahn, J.-H.

    We examined the effect of oxygen-affinity additives on the superconducting properties of magnesium diborides. The additives were elemental Y, Sm, Ca, Li compounds (LiH, LiBH4), polyethylene and polyethylene glycol, which have a higher oxygen-affinity than magnesium. The formation of magnesium oxide during in-situ sintering of magnesium diboride was inhibited by the addition of such materials. The critical current density was not improved by the additives of Y, Sm, Ca and lithium compounds in spite of reduced oxide phases. Only the addition of polyethylene and polyethylene glycol resulted in the enhanced superconducting property.

  18. Differential effects of main error correction versus secondary error correction on motor pattern of running.

    PubMed

    Corte, Stefano; Cavedon, Valentina; Milanese, Chiara

    2015-12-01

    The aim of this study was to gain a better understanding of how the run pattern varies as a consequence to main error correction versus secondary error correction. Twenty-two university students were randomly assigned to one of two training-conditions: 'main error' (ME) and 'secondary error' (SE) correction. The rear-foot strike at touchdown was hypothesized as the 'main error', whereas an incorrect shoulder position (i.e., behind the base of support) as the 'secondary error'. In order to evaluate any changes in run pattern at the foot touchdown instant, the ankle, knee and hip joint angles, the height of toe and heel (with respect to the ground), and the horizontal distance from the heel to the projected center of mass on the ground were measured. After the training-intervention, the ME group showed a significant improvement in the run pattern at the foot touchdown instant in all kinematic parameters, whereas no significant changes were found in the SE group. The results support the hypothesis that the main error can have a greater influence on the movement patterns than a secondary error. Furthermore, the findings highlight that a correct diagnosis and the correction of the 'main error' are fundamental for greater run pattern improvement.

  19. Avoidance of the dimensional incompatibility as the main reason for side effects in intrauterine contraception.

    PubMed

    Kurz, K H

    1981-01-01

    From 1976 until June 1978, 1708 medicated IUDs were inserted in nulliparous (64%), oligoparous (e.g., 1-2 births; 29%), and multiparous women (7%). 53% of the women in this study were nulligravida. The women had been fitted with CuT 200 devices with normal (32 mm) and adapted (15-30 mm) long transversal arms (n = 1550), 7 Cu 200 (n = 60), ML Cu 250 (n = 83) and T progesterone-releasing devices (n = 16). Because most women were nulliparous or oligoparous, with correspondingly small uteri and narrow cavities, prefit measurements of length and width of each individual cavity had to be taken in order to avoid dimensional incompatibility, found to be the main reason for unwanted side effects and high termination rates in intrauterine contraception. The Cavimeter, a new measuring device, was invented to enable the operator to measure cervical length, total length (the difference is the cavity length), fundus transversal, and to determine the shorter optimal fundus transversal corresponding to uterus contractions (e.g., during menstruation). Determination of cavity width appears more important than determination of length when using an IUD with a flexible shaft. Generally, the adapted Cu 200 IUD gives the best results concerning termination rates for medical reasons as well as expulsion rates (0.3%). The shorter the transversal arm of the CuT 200, the higher the acceptance rate. It is interesting to note that adaption of medicated IUDs does not lead to a higher pregnancy rate. The low expulsion rate allows the shortening of the plastic filaments intracervically. Both shortening the plastic filaments and dipping the IUD-holding tube into a 5% Betadine solution before insertion are simple methods to avoid ascending infection. Research efforts should be directed to the formulation of an easy method for outlining the uterine cavity, and to the changes in the design and dimensions and the chemical composition of the device, so as to develop a softly malleable device which can

  20. Temperature and Atomic Oxygen Effects on Helium Leak Rates of a Candidate Main Interface Seal

    NASA Technical Reports Server (NTRS)

    Penney, Nicholas; Wasowski, Janice L.; Daniels, Christopher C.

    2011-01-01

    Helium leak tests were completed to characterize the leak rate of a 54 in. diameter composite space docking seal design in support of the National Aeronautics and Space Administration s (NASA's) Low Impact Docking System (LIDS). The evaluated seal design was a candidate for the main interface seal on the LIDS, which would be compressed between two vehicles, while docked, to prevent the escape of breathable air from the vehicles and into the vacuum of space. Leak tests completed at nominal temperatures of -30, 20, and 50 C on untreated and atomic oxygen (AO) exposed test samples were examined to determine the influence of both test temperature and AO exposure on the performance of the composite seal assembly. Results obtained for untreated seal samples showed leak rates which increased with increased test temperature. This general trend was not observed in tests of the AO exposed specimens. Initial examination of collected test data suggested that AO exposure resulted in higher helium leak rates, however, further analysis showed that the differences observed in the 20 and 50 C tests between the untreated and AO exposed samples were within the experimental error of the test method. Lack of discernable trends in the test data prevented concrete conclusions about the effects of test temperature and AO exposure on helium leak rates of the candidate seal design from being drawn. To facilitate a comparison of the current test data with results from previous leak tests using air as the test fluid, helium leak rates were converted to air leak rates using standard conversion factors for viscous and molecular flow. Flow rates calculated using the viscous flow conversion factor were significantly higher than the experimental air leakage values, whereas values calculated using the molecular flow conversion factor were significantly lower than the experimentally obtained air leak rates. The difference in these sets of converted flow rates and their deviation from the

  1. Investigation of the effectiveness of smoke suppressant fuel additives for turbojet applications. Master's thesis

    SciTech Connect

    Bramer, J.R.

    1982-10-01

    Seven fuel additives were tested to investigate their effectiveness at reducing exhaust stack gas opacity in a turbojet test cell. Exhaust particle sizes and mass concentrations were determined at the engine and stack exhausts using measurements of light transmittance at three frequencies. Particle samples were also collected at the engine exhaust and measured with a scanning electron microscope to verify the optical technique. Nitrous oxide emissions were measured at the test cell stack exhaust. Four of the additives tested were found effective at reducing stack exhaust opacity and particulate mass concentration. None of the additives had any measurable effect on particle diameters. No meaningful changes in particle size or mass occurred between the engine and stack exhausts. The optical technique for determining particle size was verified effective using the scanning electron microscope. No additive had any significant effect on nitrous oxide production.

  2. Effect of urea addition on giant reed ensilage and subsequent methane production by anaerobic digestion.

    PubMed

    Liu, Shan; Ge, Xumeng; Liew, Lo Niee; Liu, Zhe; Li, Yebo

    2015-09-01

    The effect of urea addition on giant reed ensilage and sequential anaerobic digestion (AD) of the ensiled giant reed was evaluated. The dry matter loss during ensilage (up to 90 days) with or without urea addition was about 1%. Addition of 2% urea enhanced production of lactic acid by about 4 times, and reduced production of propionic acid by 2-8 times. Besides, urea addition reduced degradation of cellulose and hemicellulose, and increased degradation of lignin in giant reed during ensilage. Ensilage with or without urea addition had no significant effects on the enzymatic digestibility of giant reed, but ensilage with urea addition achieved a cumulative methane yield of 173 L/kg VS, which was 18% higher than that of fresh giant reed. The improved methane yield of giant reed could be attributed to the production of organic acids and ethanol during ensilage.

  3. Additivity of Feature-Based and Symmetry-Based Grouping Effects in Multiple Object Tracking.

    PubMed

    Wang, Chundi; Zhang, Xuemin; Li, Yongna; Lyu, Chuang

    2016-01-01

    Multiple object tracking (MOT) is an attentional process wherein people track several moving targets among several distractors. Symmetry, an important indicator of regularity, is a general spatial pattern observed in natural and artificial scenes. According to the "laws of perceptual organization" proposed by Gestalt psychologists, regularity is a principle of perceptual grouping, such as similarity and closure. A great deal of research reported that feature-based similarity grouping (e.g., grouping based on color, size, or shape) among targets in MOT tasks can improve tracking performance. However, no additive feature-based grouping effects have been reported where the tracking objects had two or more features. "Additive effect" refers to a greater grouping effect produced by grouping based on multiple cues instead of one cue. Can spatial symmetry produce a similar grouping effect similar to that of feature similarity in MOT tasks? Are the grouping effects based on symmetry and feature similarity additive? This study includes four experiments to address these questions. The results of Experiments 1 and 2 demonstrated the automatic symmetry-based grouping effects. More importantly, an additive grouping effect of symmetry and feature similarity was observed in Experiments 3 and 4. Our findings indicate that symmetry can produce an enhanced grouping effect in MOT and facilitate the grouping effect based on color or shape similarity. The "where" and "what" pathways might have played an important role in the additive grouping effect.

  4. 78 FR 24386 - Electronic Fund Transfers; Determination of Effect on State Laws (Maine and Tennessee)

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-25

    ... requirements for gift cards, which provide that any expiration date must printed on the card (i.e., if no expiration date is printed, then the card cannot expire). The commenters stated that, because the Maine and... that conflicts with what is printed on the card. In light of these arguments, industry commenters...

  5. Non-additive effects of intra- and interspecific competition between two larval salamanders.

    PubMed

    Anderson, Thomas L; Whiteman, Howard H

    2015-05-01

    Assessment of the relative strengths of intra- and interspecific competition has increased in recent years and is critical to understanding the importance of competition. Yet, whether intra- and interspecific competition can have non-additive effects has rarely been tested. The resulting fitness consequences of such non-additive interactions are important to provide the context necessary to advance our understanding of competition theory. We compared the strength of additive and non-additive intra- and interspecific competition by manipulating densities of a pair of larval salamanders (Ambystoma talpoideum and A. maculatum) in experimental mesocosms within a response surface design. Intraspecific density had the strongest effect on the strength of competition for both species, and few observed comparisons indicated interspecific competition was an important factor in predicting body size, growth or larval period length of either species. Non-additive effects of intra- and interspecific competition influenced some response variables, including size and mass at metamorphosis in A. maculatum, but at a reduced strength compared to intraspecific effects alone. Intraspecific competition was thus the dominant biotic interaction, but non-additive effects also impact the outcome of competition in these species, validating the importance of testing for and incorporating non-additive density effects into competition models.

  6. Effect of the interaction between dye and acetic acid on the decomposition of Basic Green 4 with additive by ozone.

    PubMed

    Pérez, Arizbeth A; Poznyak, Tatiana I; Chairez, Jorge I

    2014-01-01

    This research investigated the ozonation of Basic Green 4 (BG4) under the presence of acetic acid (AA). This acid is used as a textile additive for many industrial dyes derived from triphenylmethane. Determining the effect of this additive on discoloration, degradation dynamics, and final by-product distribution is the main objective of this study. The reaction system was the ozonation of a dye solution in co-solvents. This solution (dye and AA) was considered a simplified version of real BG4 dyeing wastewaters supplied with additives. The dye concentration was set to 50, 150, and 250 mg/L without pH adjustment (pH = 3). This low value was forced by the AA. Ozonation reaction with dye was mainly done by a direct molecular mechanism. The discoloration dynamics of BG4 without and with the additive were determined by ultraviolet and visible wavelength spectroscopy. The dye decomposition and the intermediate and final product formation-decomposition dynamics were followed by high-performance liquid chromatography. The effects of AA in the ozonation results were significant in the following ways: 1) a possible complex, formed between AA and the dye, changed ozone consumption; 2) the presence of additive decelerated the dye discoloration and decomposition; and 3) the number of by-products was dissimilar in both systems, with and without the additive the ozonation. The accumulation of organic acids with low molecular weight was determined in both systems, with and without the additive. Only one by-product was obtained in ozonation when AA participated in the reactor. A possible reaction mechanism is proposed for the system dye-AA-ozone.

  7. Synergistic effect of additives including multifunctional acrylates in wood plastic composites

    NASA Astrophysics Data System (ADS)

    Khan, Mubarak A.; Idriss Ali, K. M.; Garnett, John L.

    1993-07-01

    Wood Plastic Composite (WPC) was prepared with simul (soft wood, density = 0.4g/cc) and butylmethacrylate (BMA) monomer using 10% methanol as the swelling agent. Effect of additives including (i) multifunctional acrylates such as tripropylene glycol diacrylate (TPGDA), trimethylol propane triacrylate (TMPTA) (ii) oligomer acrylates like the urethane (UA), epoxy (EA) and polyester (PEA) acrylates and (iii) N-vinyl pyrrolidone (NVP) was investigated using 1 to 3 Mrad dose at 0.8 Mrad/h. Synergistic increases in polymer loading yields was achieved in presence of the additives, particularly with the trifunctional acrylate (TMPTA). In addition, acid as well as urea were also used as co-additives and synergistic enhancement in yields of polymer loading were obtained. The synergistic polymer loading by acid addition causes substantial decrease in tensile strength of the composite; but other additives and co-additives increase both the polymer loading and the tensile strength in these systems.

  8. Effectiveness of the Touch Math Technique in Teaching Basic Addition to Children with Autism

    ERIC Educational Resources Information Center

    Yikmis, Ahmet

    2016-01-01

    This study aims to reveal whether the touch math technique is effective in teaching basic addition to children with autism. The dependent variable of this study is the children's skills to solve addition problems correctly, whereas teaching with the touch math technique is the independent variable. Among the single-subject research models, a…

  9. Metabolic effects of ß-glucans addition to corn maize flour

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The addition of ß-glucans to degermed precooked corn maize flour produced favorably low metabolic responses in healthy young subjects. The increase in viscosity in the small intestine during the digestion period is the proposed mechanism for this effect. The addition of ß-glucans to corn maize pro...

  10. Parental Anxiety and Child Symptomatology: An Examination of Additive and Interactive Effects of Parent Psychopathology

    ERIC Educational Resources Information Center

    Burstein, Marcy; Ginsburg, Golda S.; Tein, Jenn-Yun

    2010-01-01

    The current study examined relations between parent anxiety and child anxiety, depression, and externalizing symptoms. In addition, the study tested the additive and interactive effects of parent anxiety with parent depression and externalizing symptoms in relation to child symptoms. Forty-eight parents with anxiety disorders and 49 parents…

  11. Additivity of Feature-Based and Symmetry-Based Grouping Effects in Multiple Object Tracking

    PubMed Central

    Wang, Chundi; Zhang, Xuemin; Li, Yongna; Lyu, Chuang

    2016-01-01

    Multiple object tracking (MOT) is an attentional process wherein people track several moving targets among several distractors. Symmetry, an important indicator of regularity, is a general spatial pattern observed in natural and artificial scenes. According to the “laws of perceptual organization” proposed by Gestalt psychologists, regularity is a principle of perceptual grouping, such as similarity and closure. A great deal of research reported that feature-based similarity grouping (e.g., grouping based on color, size, or shape) among targets in MOT tasks can improve tracking performance. However, no additive feature-based grouping effects have been reported where the tracking objects had two or more features. “Additive effect” refers to a greater grouping effect produced by grouping based on multiple cues instead of one cue. Can spatial symmetry produce a similar grouping effect similar to that of feature similarity in MOT tasks? Are the grouping effects based on symmetry and feature similarity additive? This study includes four experiments to address these questions. The results of Experiments 1 and 2 demonstrated the automatic symmetry-based grouping effects. More importantly, an additive grouping effect of symmetry and feature similarity was observed in Experiments 3 and 4. Our findings indicate that symmetry can produce an enhanced grouping effect in MOT and facilitate the grouping effect based on color or shape similarity. The “where” and “what” pathways might have played an important role in the additive grouping effect. PMID:27199875

  12. Experimental and modeling study of the effects of multicomponent gas additives on selective non-catalytic reduction process.

    PubMed

    Cao, Qingxi; Wu, Shaohua; Lui, Hui; Liu, Dunyu; Qiu, Penghua

    2009-08-01

    The influence of multicomponent additives on NO reduction by selective non-catalytic reduction process has been investigated experimentally in an electricity-heated tube reactor. The multicomponent additives are composed of two species of CO, CH(4) and H(2), and the molar ratio of their two components varies from 1/3 to 3/1. The results show that all the investigated additives could decrease the optimal temperature for NO reduction effectively, but the contributions of their components are different. The performance of multicomponent additive composed of CO and CH(4) depends mainly on CH(4) component. The function of CO component is shifting the temperature window for NO reduction to lower temperature slightly and narrowing the temperature window a little. The temperature window with multicomponent additive composed of H(2) and CH(4) is distinct from that with its each component, so both H(2) and CH(4) component make important contributions. While the fraction of CO is no more than that of H(2) in multicomponent additives composed of them, the performance of multicomponent additives is dominated by H(2) component; while the fraction of CO becomes larger, the influence of CO component becomes notable. Qualitatively the modeling results using a detailed chemical kinetic mechanism exhibit the same characteristics of the temperature window shift as observed experimentally. By reaction mechanism analysis, the distinct influences of CO, CH(4) or H(2) component on the property of multicomponent additive are mainly caused by the different production rates of (*)OH radical in their own oxidation process.

  13. The effect of alkaline additives on the performance of surfactant systems designed to recover light oils

    SciTech Connect

    French, T.R.; Josephson, C.B.; Evans, D.B.

    1991-02-01

    Surfactant flooding is flexible because of the ability to optimize formulations for a wide range of reservoir conditions and crude oil types. The objective for this work was to determine if the addition of alkaline additives will allow the design of surfactant formulations that are effective for the recovery of crude oil, while, at the same time, maintaining the surfactant concentration at a much lower level than has previously been used for micellar flooding. Specifically, the focus of the work was on light, midcontinent crudes that typically have very low acid contents. These oils are typical of much of the midcontinent resource. The positive effect of alkaline additives on the phase behavior of the surfactant formulations and acidic crude oils is well known. The extension to nonacidic and slightly acidic oils is not obvious. Three crude oils, a variety of commercial surfactants, and several alkaline additives were tested. The oils had acid numbers that ranged from 0.13, which is quite low, to less than 0.01 mg KOH/g of oil. Alkaline additives were found to be very effective in recovering Delaware-Childers (OK) oil at elevated temperatures, but much less effective at reservoir temperatures. Alkaline additives were very effective with Teapot Dome (WY) oil. With Teapot Dome oil, surfactant/alkali systems produced ultralow IFT values and recovered 60% of the residual oil that remained after waterflooding. The effect of alkaline additives on recovering Hepler (KS) oil was minimal. The results of this work indicate that alkaline additives do have merit for use in surfactant flooding of low acid crude oils; however, no universal statement about applicability can be made. Each oil behaves differently, with this treatment, and the effect of alkaline additives must be determined (at reservoir conditions) for each oil. 23 refs., 13 figs., 3 tabs.

  14. Effects of maternally exposed colouring food additives on cognitive performance in rats.

    PubMed

    Doguc, Duygu Kumbul; Ceyhan, Betul Mermi; Ozturk, Mustafa; Gultekin, Fatih

    2013-08-01

    Artificial food colourings and additives (AFCAs) have long been suggested to adversely affect the learning and behaviour in children. In this study, we aimed to provide additional data to clarify the possible side effects of colouring additives on behaviour and memory. We administered acceptable daily intake values of AFCAs as a mixture (Eritrosin, Ponceau 4R, Allura Red AC, Sunset Yellow FCF, Tartrazin, Amaranth, Brilliant Blue, Azorubin and Indigotin) to female rats before and during gestation and then tested their effects on behaviour and on spatial working memory in their offspring. Effects on spatial learning and memory were evaluated by Morris water maze, behavioural effects were evaluated by open-field test and forced swim test. Our results showed that commonly used artificial food colourings have no adverse effects on spatial working memory and did not create a depressive behaviour in offspring. But they showed a few significant effects on locomotor activity as AFCAs increased some parameters of locomotor activity.

  15. Negative effects of commercial mussel dragging on eelgrass beds in Maine

    USGS Publications Warehouse

    Neckles, H.A.; Short, F.T.; Barker, S.; Kopp, B.S.

    2005-01-01

    A study by the US Geological Survey, the University of New Hampshire, and the Maine Department of Marine Resources showed that commercial mussel dragging poses a severe and long-lasting threat to eelgrass (Zostera marina). Dragging can damage large areas, with individual drag scars up to 79 acres in size found in Maine eelgrass beds. Dragging activity uproots eelgrass plants completely, removing leaves, rhizomes, and roots. Two independent methods were used to predict the rate of eelgrass recovery in heavily dragged areas. Under the best environmental conditions, complete revegetation of a dragged area would require an average of 11 years. Under conditions less favorable for eelgrass growth, such as reduced water quality, dragged areas could require more than 20 years to recover. Protection of eelgrass from commercial shellfish dragging will preserve important coastal habitat.

  16. Effects of main-sequence mass loss on the turnoff ages of population 1 clusters

    NASA Astrophysics Data System (ADS)

    Guzik, Joyce A.

    Willson, Bowen, and Struck-Marcell have proposed that stars of spectral types A through early-G lose a significant portion of their mass during the early main-sequence phase. The proposed mass loss is driven by pulsation, and facilitated by rapid rotation. One implication of this hypothesis is that the main-sequence turnoff is an invalid indicator of cluster age, as present turnoff stars may have had higher projenitor masses; hence clusters appear older than they actually are. This paper presents examples of cluster HR diagrams synthesized with mass-losing stars of solar metallicity, initial masses 1-2 M, and exponentially-decreasing mass-loss rates with e-folding times 1 to 2 Gyr. The increases in apparent turnoff age of Pop. I clusters, and the potential of the hypothesis to account for blue stragglers as normal stars that have not lost mass (or lost mass more slowly) are discussed.

  17. Effectiveness of Additives in Improving Fuel Lubricity and Preventing Pump Failure at High Temperature

    DTIC Science & Technology

    2013-01-01

    the specified 1,700 rpm, the housing pressure on pump No. 1 dropped significantly. Fuel began spewing out of test stand gear box and the pump seized...UNCLASSIFIED EFFECTIVENESS OF ADDITIVES IN IMPROVING FUEL LUBRICITY AND PREVENTING PUMP FAILURE AT HIGH TEMPERATURE INTERIM REPORT TFLRF...UNCLASSIFIED EFFECTIVENESS OF ADDITIVES IN IMPROVING FUEL LUBRICITY AND PREVENTING PUMP FAILURE AT HIGH TEMPERATURE INTERIM REPORT TFLRF No. 437

  18. The Effect of Alloy Additions on Superplasticity in Thermomechanically Processed High Magnesium Aluminum-Magnesium Alloys.

    DTIC Science & Technology

    1984-12-01

    AD-Ri55 142 THE EFFECT OF ALLOY ADDITIONS ON SUPERPLASTICITY IN I/2 THERMOMECHANICALLY PR-.(U) NAVAL POSTGRADUATE SCHOOL UNCLSSIIED MONTEREY CA R J...Ln Monterey, California DTr J U N 1985 * THESIS THE EFFECT OF ALLOY ADDITIONS ON SUPERPLASTICITY IN THERMOMECHANICALLY PROCESSED HIGH MAGNESIUM *0...ALUMINUM-MAGNESIUM ALLOYS >by 0 (Richard J. Self December 1984 C-31 Thesis Advisor: Terry McNelley Approved for public release; distribution is unlimited

  19. An electrical conductivity method for measuring the effects of additives on effective diffusivities in Portland cement pastes

    SciTech Connect

    Kyi, A.A. ); Batchelor, B. . Civil Engineering)

    1994-01-01

    Effective diffusivities are important in describing corrosion and leaching of contaminants in cementitious systems. An electrical conductivity procedure has been used to measure the effective diffusivities of compounds in cementitious systems containing the additives fly ash, silica fume, sodium silicate and bentonite. Silica fume was the most effective additive in reducing the effective diffusivity, but fly ash was the most cost effective. Diffusivities that have been measured with techniques that rely on flux of a compound through the solid were generally lower than those measured with the electrical conductivity procedure. Porosity and bulk density are not well correlated with effective diffusivity in systems containing additives.

  20. Effect of fluorapatite additive on the mechanical properties of tricalcium phosphate-zirconia composites

    NASA Astrophysics Data System (ADS)

    Sallemi, I.; Ben Ayed, F.; Bouaziz, J.

    2012-02-01

    The effect of fluorapatite addition on the mechanical properties of tricalcium phosphate - 50 wt% zirconia composites was investigated during the sintering process. The Brazilian test was used to measure the mechanical resistance of bioceramics. The mechanical properties of composites increase with the sintering temperature and with fluorapatite additive. At 1400°C, the fluorapatite additive ameliorates the densification and the mechanical resistance of tricalcium phosphate - 50 wt% zirconia composites. The 31P magic angle spinning nuclear magnetic resonance analysis of tricalcium phosphate - zirconia composites sintered with fluorapatite additives reveals the presence of tetrahedral P sites.

  1. An atomic view of additive mutational effects in a protein structure

    SciTech Connect

    Skinner, M.M.; Terwilliger, T.C.

    1996-04-01

    Substitution of a single amino acid in a protein will often lead to substantial changes in properties. If these properties could be altered in a rational way then proteins could be readily generated with functions tailored to specific uses. When amino acid substitutions are made at well-separated locations in a single protein, their effects are generally additive. Additivity of effects of amino acid substitutions is very useful because the properties of proteins with any combination of substitutions can be inferred directly from those of the proteins with single changes. It would therefore be of considerable interest to have a means of knowing whether substitutions at a particular pair of sites in a protein are likely to lead to additive effects. The structural basis for additivity of effects of mutations on protein function was examined by determining crystal structures of single and double mutants in the hydrophobic core of gene V protein. Structural effects of mutations were found to be cumulative when two mutations were made in a single protein. Additivity occurs in this case because the regions structurally affected by mutations at the two sites do not overlap even though the sites are separated by only 9 {angstrom}. Structural distortions induced by mutations in gene V protein decrease rapidly, but not isotropically, with distance from the site of mutation. It is anticipated that cases where structural and functional effects of mutations will be additive could be identified simply by examining whether the regions structurally affected by each component mutation overlap.

  2. Effect of a chromium-containing fuel additive on hot corrosion

    NASA Technical Reports Server (NTRS)

    Lowell, C. E.; Deadmore, D. L.

    1976-01-01

    Four superalloys were tested at 900 C in high velocity combustion gases containing synthetic sea salt and, in some cases, a chromium containing fuel additive. While the additive reduced hot corrosion of the alloys over the 100 hour test period, the attack was not eliminated nor was the mode of attack changed. Reduction of the number of thermal cycles had as large a beneficial effect as the Cr additive. Intermittent washing during testing had either small beneficial or adverse effects depending on the alloy.

  3. Effect of Surface-active Additives on Physical Properties of Slurries of Vapor-process Magnesium

    NASA Technical Reports Server (NTRS)

    Pinns, Murray L

    1955-01-01

    The presence of 3 to 5 percent surface-active additive gave the lowest Brookfield apparent viscosity, plastic viscosity, and yield value that were obtained for slurry fuels containing approximately 50 percent vapor-process magnesium in JP-1 fuel. The slurries settled little and were easily remixed. A polyoxyethylene dodecyl alcohol was the most effective of 13 additives tested in reducing the Brookfield apparent viscosity and the yield value of the slurry. The seven most effective additives all had a hydroxyl group plus an ester or polyoxethylene group in the molecule. The densities of some of the slurries were measured.

  4. Thermal conditions on the International Space Station: Effects of operations of the station Main Radiators on the Alpha Magnetic Spectrometer

    NASA Astrophysics Data System (ADS)

    Xie, Min; Burger, Joseph

    2016-04-01

    A thermal model of the Alpha Magnetic Spectrometer on the International Space Station (ISS) has been developed, and Thermal Desktop® (with RadCAD®) and SINDA/FLUINT software have been used to calculate the effects of the operations of the ISS Main Radiators on AMS temperatures. We find that the ISS Starboard Main Radiator has significant influence on temperatures on the port side of AMS. The simulation results are used in AMS thermal control operations.

  5. Effects of chemical additives on filtration and rheological characteristics of MBR sludge.

    PubMed

    Koseoglu, H; Yigit, N O; Civelekoglu, G; Harman, B I; Kitis, M

    2012-08-01

    The main goal of this study was to control the fouling phenomena in MBR using chemical additives. In the first phase of the study, SMP removal and bound EPS formation capacity of chemical additives were determined. Highest SMP removal (72%) was achieved by the Poly-2 additive. In the second phase of the study, short term filtration tests were conducted. Poly-1 exhibited highest performance based on membrane resistance, permeability and average TMP. According to the results obtained from constant shear rate tests in fourth phase, no significant change in viscosity with time was observed. Studies for the adaptation of rheograms to common flow models showed that chitosan and starch was not able to fit to Ostwald de Waele and Bingham models. At a shear rate of 73.4 s(-1) viscosities of all samples were close to each other. Chitosan and starch achieved highest viscosity values at the shear rate of 0.6 s(-1).

  6. Effects of main-sequence mass loss on the turnoff ages of globular clusters

    SciTech Connect

    Guzik, J.A.

    1989-01-01

    Willson, Bowen, and Struck-Marcell have proposed that globular cluster main-sequence turnoff ages can be reconciled with the lower ages of the Galaxy and universe deduced from other methods by incorporating an epoch of early main-sequence mass-loss by stars of spectral types A through early-F. The proposed mass loss is pulsation-driven, and facilitated by rapid rotation. This paper presents stellar evolution calculations of Pop. II (Z = 0.001) mass-losing stars of initial mass 0.8 to 1.6 M/sub /circle dot//, with exponentially-decreasing mass loss rates of e-folding times 0.5 to 2.0 Gyr, evolving to a final mass of 0.7 M/sub /circle dot//. The calculations indicate that a globular cluster with apparent turnoff age 18 Gyr could have an actual age as low as /approximately/12 Gyr. Observational implications that may help to verify the hypothesis, e.g. low C/N abundance ratios among red giants following first dredge-up, blue stragglers, red giant deficiencies, and signatures in cluster mass/luminosity functions, are also discussed.25 refs., 4 figs., 3 tabs.

  7. Effect of flange bolt preload on Space Shuttle main engine high pressure oxidizer turbopump housing analysis

    NASA Technical Reports Server (NTRS)

    Min, J. B.; Johnston, L. M.; Czekalski, B.

    1991-01-01

    Cracks at the seal fillet flange and the strut pilot groove of primary turbine drain passage of the space shuttle main engine (SSME) high pressure oxidizer turbopump (HPOTP) were observed and reported. Stress information for critical structural components in the SSME under actual conditions is necessary for design and life prediction analysis. However, little information is available about the stress distribution at this location under various combinations of loadings and environments. Thus, a stress analysis was conducted to determine an influence of the various operation and installation loads on the stresses of the HPOTP main mounting flange. To do this, a 3-D finite element model of the HPOTP housing was generated. A fairly comfortable margin of stresses at the flange fillet with respect to the yield stress of Inconel 718 is shown. However, it was revealed that the bending stress arising from the housing flange bolt preloads could significantly affect the stress distribution at the strut pilot groove of primary turbine drain passage in the HPOTP housing. Consequently, the information obtained from the present 3-D analysis results should be useful in guiding the development of the SSME HPOTP.

  8. Cost-effectiveness of the stream-gaging program in Maine

    USGS Publications Warehouse

    Fontaine, Richard A.; Moss, M.E.; Smath, J.A.; Thomas, W.O.

    1983-01-01

    Data uses and funding sources were identified for the 51 continuous stream gages currently being operated in Maine. Three stream-gages were identified as having insufficient reason to continue their operation. Operation of these stations were identified as having uses specific only to short-term studies; it is recommended that these stations be discontinued at the end of the data-collection phases of the studies. The remaining 45 stations should be maintained in the program for the foreseeable future. The current policy for operation of the 45-station program would require $180,300 per year. The average standard error of estimation of streamflow record is 18.5 percent. It was shown that this overall level of accuracy at the 45 sites could be maintained with a budget of $170,000 if the gaging resources were redistributed among the gages. A minimum budget of $155,000 is required to operate the 45-gage program; a budget less than this does not permit proper service and maintenance of the gages and recorders. At the minimum budget, the average standard error is 26.0 percent. The maximum budget analyzed was $350,000, which resulted in an average standard error of 9.2 percent. Large parts of Maine 's interior were identified as having sparse stream-flow data. It was recommended that this sparsity should be remedied as funds can be made available. (USGS)

  9. Nitrogen Addition Altered the Effect of Belowground C Allocation on Soil Respiration in a Subtropical Forest

    PubMed Central

    He, Tongxin; Wang, Qingkui; Wang, Silong; Zhang, Fangyue

    2016-01-01

    The availabilities of carbon (C) and nitrogen (N) in soil play an important role in soil carbon dioxide (CO2) emission. However, the variation in the soil respiration (Rs) and response of microbial community to the combined changes in belowground C and N inputs in forest ecosystems are not yet fully understood. Stem girdling and N addition were performed in this study to evaluate the effects of C supply and N availability on Rs and soil microbial community in a subtropical forest. The trees were girdled on 1 July 2012. Rs was monitored from July 2012 to November 2013, and soil microbial community composition was also examined by phospholipid fatty acids (PLFAs) 1 year after girdling. Results showed that Rs decreased by 40.5% with girdling alone, but N addition only did not change Rs. Interestingly, Rs decreased by 62.7% under the girdling with N addition treatment. The reducing effect of girdling and N addition on Rs differed between dormant and growing seasons. Girdling alone reduced Rs by 33.9% in the dormant season and 54.8% in the growing season compared with the control. By contrast, girdling with N addition decreased Rs by 59.5% in the dormant season and 65.4% in the growing season. Girdling and N addition significantly decreased the total and bacterial PLFAs. Moreover, the effect of N addition was greater than girdling. Both girdling and N addition treatments separated the microbial groups on the basis of the first principal component through principal component analysis compared with control. This indicated that girdling and N addition changed the soil microbial community composition. However, the effect of girdling with N addition treatment separated the microbial groups on the basis of the second principal component compared to N addition treatment, which suggested N addition altered the effect of girdling on soil microbial community composition. These results suggest that the increase in soil N availability by N deposition alters the effect of

  10. Effects of soil warming and nitrogen addition on soil respiration in a New Zealand tussock grassland.

    PubMed

    Graham, Scott L; Hunt, John E; Millard, Peter; McSeveny, Tony; Tylianakis, Jason M; Whitehead, David

    2014-01-01

    Soil respiration (RS) represents a large terrestrial source of CO2 to the atmosphere. Global change drivers such as climate warming and nitrogen deposition are expected to alter the terrestrial carbon cycle with likely consequences for RS and its components, autotrophic (RA) and heterotrophic respiration (RH). Here we investigate the impacts of a 3°C soil warming treatment and a 50 kg ha(-1) y(-1) nitrogen addition treatment on RS, RH and their respective seasonal temperature responses in an experimental tussock grassland. Average respiration in untreated soils was 0.96±0.09 μmol m(-2) s(-1) over the course of the experiment. Soil warming and nitrogen addition increased RS by 41% and 12% respectively. These treatment effects were additive under combined warming and nitrogen addition. Warming increased RH by 37% while nitrogen addition had no effect. Warming and nitrogen addition affected the seasonal temperature response of RS by increasing the basal rate of respiration (R10) by 14% and 20% respectively. There was no significant interaction between treatments for R10. The treatments had no impact on activation energy (E0). The seasonal temperature response of RH was not affected by either warming or nitrogen addition. These results suggest that the additional CO2 emissions from New Zealand tussock grassland soils as a result of warming-enhanced RS constitute a potential positive feedback to rising atmospheric CO2 concentration.

  11. Comparing Main and Collateral Effects of Extinction and Differential Reinforcement of Alternative Behavior

    ERIC Educational Resources Information Center

    Petscher, Erin Seligson; Bailey, Jon S.

    2008-01-01

    This study evaluated the effects and collateral effects of extinction (EXT) and differential reinforcement of alternative behavior (DRA) interventions with inappropriate vocalizations and work refusal. Both interventions have been used frequently to reduce problem behaviors. The benefits of these interventions have been established yet may be…

  12. Kinetic effect of Pd additions on the hydrogen uptake of chemically activated, ultramicroporous carbon

    SciTech Connect

    Bhat, Vinay V; Contescu, Cristian I; Gallego, Nidia C

    2010-01-01

    The effect of mixing chemically-activated ultramicroporous carbon (UMC) with Pd nanopowder is investigated. Results show that Pd addition doubles the rate of hydrogen uptake, but does not enhance the hydrogen capacity or improve desorption kinetics. The effect of Pd on the rate of hydrogen adsorption supports the occurrence of the hydrogen spillover mechanism in the Pd - UMC system.

  13. Comparing main and collateral effects of extinction and differential reinforcement of alternative behavior.

    PubMed

    Petscher, Erin Seligson; Bailey, Jon S

    2008-07-01

    This study evaluated the effects and collateral effects of extinction (EXT) and differential reinforcement of alternative behavior (DRA) interventions with inappropriate vocalizations and work refusal. Both interventions have been used frequently to reduce problem behaviors. The benefits of these interventions have been established yet may be outweighed by the reported negative side effects that result. However, these collateral effects have rarely been measured or reported. DRA produced the most rapid reductions in behavior for 4 of the 5 participants. Other behaviors were measured for changes and showed that the desirable collateral effect of academic engagement tended to be higher during EXT than DRA. No evidence of EXT bursts was present with any participant, although EXT-induced aggression occurred with 1 participant.

  14. Differences in the effects of solution additives on heat- and refolding-induced aggregation.

    PubMed

    Hamada, Hiroyuki; Takahashi, Ryouta; Noguchi, Takumi; Shiraki, Kentaro

    2008-01-01

    Although a number of low-molecular-weight additives have been developed to suppress protein aggregation, it is unclear whether these aggregation suppressors affect various aggregation processes in the same manner. In this study, we evaluated the differences in the effect of solution additives on heat- and refolding-induced aggregation in the presence of guanidine (Gdn), arginine (Arg), and spermidine (Spd), and the comparable analysis showed the following differences: (i) Gdn did not suppress thermal aggregation but increased the yield of oxidative refolding. (ii) Spd showed the highest effect for heat-induced aggregation suppression among tested compounds, although it promoted aggregation in oxidative refolding. (iii) Arg was effective for both aggregation processes. Lysozyme solubility assay and thermal unfolding experiment showed that Spd was preferentially excluded from native lysozyme and Arg and Gdn solubilized the model state of intermediates during oxidative refolding. This preference of additives to protein surfaces is the cause of the different effect on aggregation suppression.

  15. Interactive effects between N addition and disturbance on boreal forest ecosystem structure and function

    NASA Astrophysics Data System (ADS)

    Nordin, Annika; Strengbom, Joachim; From, Fredrik

    2014-05-01

    In management of boreal forests, nitrogen (N) enrichment from atmospheric deposition or from forest fertilization can appear in combination with land-use related disturbances, i.e. tree harvesting by clear-felling. Long-term interactive effects between N enrichment and disturbance on boreal forest ecosystem structure and function are, however, poorly known. We investigated effects of N enrichment by forest fertilization done > 25 years ago on forest understory species composition in old-growth (undisturbed) forests, and in forests clear-felled 10 years ago (disturbed). In clear-felled forests we also investigated effects of the previous N addition on growth of tree saplings. The results show that the N enrichment effect on the understory species composition was strongly dependent on the disturbance caused by clear-felling. In undisturbed forests, there were small or no effects on understory species composition from N addition. In contrast, effects were large in forests first exposed to N addition and subsequently disturbed by clear-felling. Effects of N addition differed among functional groups of plants. Abundance of graminoids increased (+232%) and abundance of dwarf shrubs decreased (-44%) following disturbance in N fertilized forests. For vascular plants, the two perturbations had contrasting effects on α-(within forests) and β-diversity (among forests): in disturbed forests, N addition reduced, or had no effect on α-diversity, while β-diversity increased. For bryophytes, negative effects of disturbance on α-diversity were smaller in N fertilized forests than in forests not fertilized, while neither N addition nor disturbance had any effects on β-diversity. Moreover, sapling growth in forests clear-felled 10 years ago was significantly higher in previously N fertilized forests than in forests not fertilized. Our study show that effects of N addition on plant communities may appear small, short-lived, or even absent until exposed to a disturbance. This

  16. Effects of aging and service wear on main steam isolation valves and valve operators

    SciTech Connect

    Clark, R.L.

    1996-03-01

    In recent years main steam isolation valve (MSIV operating problems have resulted in significant operational transients (e.g., spurious reactor trips, steam generator dry out, excessive valve seat leakage), increased cost, and decreased plant availability. A key ingredient to an engineering-oriented reliability improvement effort is a thorough understanding of relevant historical experience. A detailed review of historical failure data available through the Institute of Nuclear Power Operation`s Nuclear Plant Reliability Data System has been conducted for several types of MSIVs and valve operators for both boiling-water reactors and pressurized-water reactors. The focus of this review is on MSIV failures modes, actuator failure modes, consequences of failure on plant operations, method of failure detection, and major stressors affecting both valves and valve operators.

  17. Repeated forced swim stress has additive effects in anxiety behavior and in cathecolamine levels of adult rats exposed to deltamethrin.

    PubMed

    Habr, Soraya F; Macrini, Daclé J; Florio, Jorge C; Bernardi, Maria M

    2014-01-01

    Deltamethrin (DTM) is a type II pyrethroid insecticide that elicits autonomic and neuroendocrine responses that indicate high levels of stress, presumably caused by the neurotoxic effect of the insecticide. This study investigated the effect of DTM exposure (10 mg/kg, p.o.) and an additional stress induced in the forced swim test (FST) in behavioral tasks related to anxiety, serum corticosterone levels, and striatal neurotransmitter levels. Open field behavior and social interaction were evaluated after DTM administration (10 mg kg(-1), p.o). DTM per se reduced rearing frequency in the open field, but no alterations in locomotion frequency or immobility duration were detected. Stress increased immobility duration compared with non-stressed animals. DTM reduced social interaction and increased corticosterone levels, and these effects were enhanced in stressed animals. Mainly stress affected dopaminergic and serotoninergic activity. In anxiety behavior and in both neurotransmitters and metabolites levels it was observed an additive effect of stress in DTM treated rat data. These results indicate that DTM enhanced the anxiogenic responses and stress had an additive effect over the DTM stress. The neurochemical data did not indicate an interaction between stress and DTM exposure. The present results maybe important for implementing pyrethroid insecticide safety standards.

  18. The effects of flue gas desulfurization (FGD) system additives on solid by-products. Final report

    SciTech Connect

    Huyck, K.A.; Tatum, G.S.; DeKraker, D.P.

    1995-12-01

    This study was designed to examine characteristics of by-products from flue gas desulfurization (FGD) systems that use performance-enhancing additives. The by-products were evaluated for handling, disposal, properties, and utilization potential. This study was designed to identify potential operation-limiting consequences (fatal flaws) caused by using FGD system additives. It was not intended to be an all-encompassing study of the possible process, environmental, and utilization circumstances at each plant. Seven utilities conducting additive testing agreed to provide samples for this study both before and during their testing. Solid samples were collected from FGD systems using the following additives: di-basic acid (DBA), which is a mixture of succinic, glutaric, and adipic acids; formate; sulfur; ethylene diamine tetraacetic acid (EDTA); and chloride. Changes in handling properties that may alter process operations were observed at sites where DBS was used. Changes in leaching behavior, permeability and unconfined compressive strength (properties that affect by-product disposal properties) showed no clear trend for additive or system type. The intent of this study is to provide an overall assessment of potential system-limiting effects of FGD additive use. There were no overriding problems relating to disposal with the use of additives. However, properties of solids produced with and without additives should be tested at each site prior to use of an FGD system additive. This is necessary because of the variability in state disposal and permitting requirements and the influence of specific operating conditions on by-product properties.

  19. Effectiveness of Emittance Bumps in the NLC and US Cold LC Main Linear Accelerators (LCC-0138)

    SciTech Connect

    Tenenbaum, P

    2004-05-13

    We report on a series of studies on the effectiveness of closed orbit bumps in the linacs of the NLC and the USColdLC. In the first study, emittance dilutions of a pure-wakefield or pure-dispersion character are introduced in each linac, and a set of emittance bumps is tested to determine the most effective bump location in the linac, and the net effectiveness. In the second study, a more realistic set of dilutions are introduced and the wakefield bumps used in the first study are applied.

  20. Major mental illness and violence history as predictors of institutional misconduct and recidivism: main and interaction effects.

    PubMed

    Walters, Glenn D; Crawford, Gregory

    2014-06-01

    The purpose of this study was to ascertain whether major mental illness (MMI) and violence history (VH) interact in their effect on institutional misconduct and recidivism. MMI and VH were measured in two overlapping groups of male medium security federal prisoners and correlated with institutional misconduct and recidivism. Age and the main effect of MMI were significant predictors of general and aggressive infractions in 2,627 male prison inmates before the MMI × VH interaction term was entered into a Cox regression equation. Once the interaction term was entered into the equation, the MMI × VH interaction predicted relative hazard (risk) but neither main effect (MMI, VH) was significant. There was no interaction effect, however, when age, prior substance abuse, MMI, VH, and the MMI × VH interaction were used to predict general and aggressive recidivism in a group of 1,163 male inmates previously released from custody. Age and the VH main effect achieved significance in both recidivism analyses whereas the MMI main effect failed to achieve significance in either analysis. Whereas major mental illness was not a risk factor for future antisocial behavior in current and former prison inmates, when paired with a history of violence it predicted increased risk of general and aggressive institutional misconduct. Violence history, on the other hand, was a consistent predictor of recidivism. These results indicate that it may be advisable to review both mental health and violence history when screening inmates as a prelude to managing concomitant MMI and violence propensity.

  1. Effects of magnetic ion-exchange resin addition during coagulation on floc properties and membrane filtration.

    PubMed

    Choi, Yang Hun; Kweon, Ji Hyang; Jeong, Young Mi; Kwon, Soonbuhm; Kim, Hyung-Soo

    2010-03-01

    The application of magnetic ion-exchange resin (MIEX) during chemical coagulation was investigated for the removal of organic matters responsible for fouling in membrane processes. Two different coagulants were used-polyaluminium chloride (PAC1) and polyaluminum chloride silicate (PACS). The MIEX addition during coagulation with both PAC1 and PACS considerably enhanced removal of dissolved organic carbon. Coagulation with MIEX treatment substantially removed all portions of natural organic matter (NOM), while the MIEX treatment alone effectively removed the hydrophobic and transphilic portions of NOM. The enhanced NOM removal by PAC1 coagulation with the addition of MIEX had positive effects on membrane flux at moderate transmembrane pressure conditions. However, the almost identical flux patterns were reported in the experiments of coagulation with PACS and PACS with MIEX addition. The results of the specific cake resistances indicated that the MIEX addition substantially decreased the resistances. The larger size distributions of PAC1 with MIEX corresponded well with the flux improvement.

  2. Effects of additives on volume change on melting, surface tension, and viscosity of liquid aluminum oxide

    NASA Technical Reports Server (NTRS)

    Bates, J. L.; Rasmussen, J. J.

    1972-01-01

    The effects of various oxide additives on the volume change on melting, the surface tension, and the viscosity of liquid Al2O3 were studied. Additives of Sm2O3, MgO, and Y2O3 which form solid solutions, compounds, and multiphase solids with Al2O3 were studied. A review of the property data for Al2O3 and Al2O3 containing oxide additives is presented. Oxide additives to Al2O3 reduce the volume change on melting and with the exception of SiO2 lower the viscosity; surface tensions change with oxide additives, but changes vary with different container material. Viscosity and volume change on melting appeared to be significantly more important for studying the properties of liquid oxides than surface tension. Supercooling of 270 K of yttrium aluminum garnet was observed.

  3. Effect of the additional anode layers on the absorption enhancement characteristic of plasmonic organic solar cells

    NASA Astrophysics Data System (ADS)

    Yoo, Sanghyuk; Kim, Jungho

    2014-12-01

    We numerically investigate the effect of additional anode layers on the absorption enhancement characteristic of pyramidal-grating plasmonic organic solar cells (OSCs) using the finite element method. The behaviors of the plasmonic absorption enhancement are compared between a “simple” structure consisting of only the active and metal cathode layers and a “practical” structure with the additional anode layers. The plasmonic absorption enhancement is identified by comparing the polarization-dependent absorbance spectra between the planar and plasmonic OSCs. When the active-layer thickness is small, the plasmonic resonance condition changes owing to the addition of the anode layers. When the active-layer thickness is large, the plasmonic resonance condition and corresponding absorption behavior show a slight difference irrespective of the inclusion of the additional anode layers. Therefore, the additional anode layers should be included in the optical analysis and design of plasmonic OSCs when the active-layer thickness is small.

  4. Solvent additive effects on small molecule crystallization in bulk heterojunction solar cells probed during spin casting.

    PubMed

    Perez, Louis A; Chou, Kang Wei; Love, John A; van der Poll, Thomas S; Smilgies, Detlef-M; Nguyen, Thuc-Quyen; Kramer, Edward J; Amassian, Aram; Bazan, Guillermo C

    2013-11-26

    Solvent additive processing can lead to drastic improvements in the power conversion efficiency (PCE) in solution processable small molecule (SPSM) bulk heterojunction solar cells. In situ grazing incidence wide-angle X-ray scattering is used to investigate the kinetics of crystallite formation during and shortly after spin casting. The additive is shown to have a complex effect on structural evolution invoking polymorphism and enhanced crystalline quality of the donor SPSM.

  5. Effect of dimethyl sulfoxide addition on ultrasonic degradation of methylene blue

    NASA Astrophysics Data System (ADS)

    Shimakage, Kaho; Kobayashi, Daisuke; Naya, Masakazu; Matsumoto, Hideyuki; Shimada, Yuichiro; Otake, Katsuto; Shono, Atsushi

    2016-07-01

    The ultrasonic degradation of methylene blue was carried out in the absence and presence of dimethyl sulfoxide (DMSO) as a radical scavenger for various frequencies, and the effects of DMSO addition on the degradation rate constant estimated by assuming first-order kinetics were investigated. The degradation reaction rate decreased with DMSO addition, and hydroxyl radicals were observed to play important roles in the degradation of methylene blue. However, the degradation reaction did not stop with DMSO addition, and the degradation rate constant in the presence of DMSO was not affected by ultrasonic frequency.

  6. Effects of conifer release with glyphosate on summer forage abundance for deer in Maine

    USGS Publications Warehouse

    Vreeland, J.K.; Servello, F.A.; Griffith, B.

    1998-01-01

    Effects of conifer release with glyphosate on summer forage availability for large herbivores in northern forests have received relatively little study. We determined effects of glyphosate treatment of clearcuts on abundance of summer foods for white-tailed deer (Odocoileus virginianus) at 1 and 7-10 years posttreatment. We measured the abundance (percent cover in a 0- to 1.8-m height stratum) of five forage classes for deer (leaves of deciduous trees, leaves of deciduous shrubs, forbs, grasses, ferns) on 12 clearcuts (six treated, six untreated) to determine 1-year effects and on 10 clearcuts (five treated, five untreated) to determine 7- to 10-year effects. Abundance of leaves of deciduous trees was greater on untreated sites (38 versus 11%) at 1 year posttreatment, but the difference was less (18 versus 12%) at 7-10 years posttreatment (age x treatment interaction, P = 0.005). Leaves of deciduous shrubs exhibited a similar pattern. Abundance of forbs was similar (13-14%) at 1 year posttreatment but greater on treated sites (29 versus 15%) at 7-10 years posttreatment (P = 0.03). Grasses and ferns were less abundant than other forage classes. Overall, glyphosate application initially decreased the abundance of leaves of deciduous trees and shrubs used as food in summer, but the longer term positive effects on forb abundance may result in little net change in overall habitat value.

  7. Effects of Metal Powder Addition in Ni-Sheathed PIT MgB2 Tapes

    NASA Astrophysics Data System (ADS)

    Tachikawa, K.; Yamada, Y.; Katagiri, K.; Kumakura, H.; Iwamoto, A.; Watanabe, K.

    2004-06-01

    The effect of different metal powder additions on the transport current and stress/strain performance of ex-situ processed MgB2 tapes with Ni sheath has been studied. The metal powder added to the core exhibits elongated morphology after the fabrication. The addition of low melting point metal powder, e.g. In and Sn, produces an appreciable increase in the Jc of MgB2 core. An addition of 10 vol% In enhances Jc by a factor of 6 to 7 after the combination of rolling and annealing at 200 °C, up to the order of 105 A/cm2 at 0.5 T and 4.2 K. An addition of 10 vol% Sn enhances Jc by a factor of ˜ 3. The In and Sn additions also appreciably increase the n-value of the current-voltage transition. Both In and Sn metals infiltrate into gaps between MgB2 grains, improving the linkage of the grains. Current may transfer through the impregnated metal by the proximity effect. Furthermore, the metal powder addition appreciably improves the strain tolerance in MgB2 tapes. The low melting point metal powder addition is a relatively simple and easy approach to yield better transport current and stress/strain performance in ex-situ MgB2 tapes.

  8. Effects of additional food in a delayed predator-prey model.

    PubMed

    Sahoo, Banshidhar; Poria, Swarup

    2015-03-01

    We examine the effects of supplying additional food to predator in a gestation delay induced predator-prey system with habitat complexity. Additional food works in favor of predator growth in our model. Presence of additional food reduces the predatory attack rate to prey in the model. Supplying additional food we can control predator population. Taking time delay as bifurcation parameter the stability of the coexisting equilibrium point is analyzed. Hopf bifurcation analysis is done with respect to time delay in presence of additional food. The direction of Hopf bifurcations and the stability of bifurcated periodic solutions are determined by applying the normal form theory and the center manifold theorem. The qualitative dynamical behavior of the model is simulated using experimental parameter values. It is observed that fluctuations of the population size can be controlled either by supplying additional food suitably or by increasing the degree of habitat complexity. It is pointed out that Hopf bifurcation occurs in the system when the delay crosses some critical value. This critical value of delay strongly depends on quality and quantity of supplied additional food. Therefore, the variation of predator population significantly effects the dynamics of the model. Model results are compared with experimental results and biological implications of the analytical findings are discussed in the conclusion section.

  9. Effect of exogenous phosphorus addition on soil respiration in Calamagrostis angustifolia freshwater marshes of Northeast China

    NASA Astrophysics Data System (ADS)

    Song, Changchun; Liu, Deyan; Song, Yanyu; Yang, Guisheng; Wan, Zhongmei; Li, Yingchen; Xu, Xiaofeng

    2011-03-01

    Anthropogenic activities have increased phosphorus (P) inputs to wetland ecosystems. However, little is known about the effect of P enrichment on soil respiration in these ecosystems. To understand the effect of P enrichment on soil respiration, we conducted a field experiment in Calamagrostis angustifolia-dominated freshwater marshes, the Sanjiang Plain, Northeast China. We investigated soil respiration in the first growing season after P addition at four rates (0, 1.2, 4.8 and 9.6 g P m-2 year-1). In addition, we also examined aboveground biomass, soil labile C fractions (dissolved organic C, DOC; microbial biomass C, MBC; easily oxidizable C, EOC) and enzyme activities (invertase, urease and acid phosphatase activities) following one year of P addition. P addition decreased soil respiration during the growing season. Dissolved organic C in soil pore water increased after P addition at both 5 and 15 cm depths. Moreover, increased P input generally inhibited soil MBC and enzyme activities, and had no effects on aboveground biomass and soil EOC. Our results suggest that, in the short-term, soil respiration declines under P enrichment in C. angustifolia-dominated freshwater marshes of Northeast China, and its extent varies with P addition levels.

  10. Effect of additives on isothermal crystallization kinetics and physical characteristics of coconut oil.

    PubMed

    Chaleepa, Kesarin; Szepes, Anikó; Ulrich, Joachim

    2010-05-01

    The effect of lauric acid and low-HLB sucrose esters (L-195, S170) on the isothermal crystallization of coconut oil was investigated by differential scanning calorimetry. The fundamental crystallization parameters, such as induction time of nucleation and crystallization rate, were obtained by using the Gompertz equation. The Gibb's free energy of nucleation was calculated via the Fisher-Turnbull equation based on the equilibrium melting temperature. All additives, investigated in this work, proved to have an inhibition effect on nucleation and crystallization kinetics of coconut oil. Our results revealed that the inhibition effect is related to the dissimilarity of the molecular characteristics between coconut oil and the additives. The equilibrium melting temperature (T(m) degrees ) of the coconut oil-additive mixtures estimated by the Hoffman-Weeks method was decreased with the addition of lauric acid and increased by using sucrose esters as additives. Micrographs showing simultaneous crystallization of coconut oil and lauric acid indicated that strong molecular interaction led to the increase in lamellar thickness resulting in the T(m) degrees depression of coconut oil. The addition of L-195 modified the crystal morphology of coconut oil into large, dense, non-porous crystals without altering the polymorphic occurrence of coconut oil. The enhancement in lamellar thickness and crystal perfection supported the T(m) degrees elevation of coconut oil.

  11. [Effects of superphosphate addition on NH3 and greenhouse gas emissions during vegetable waste composting].

    PubMed

    Yang, Yan; Sun, Qin-ping; Li, Ni; Liu, Chun-sheng; Li, Ji-jin; Liu, Ben-sheng; Zou, Guo-yuan

    2015-01-01

    To study the effects of superphosphate (SP) on the NH, and greenhouse gas emissions, vegetable waste composting was performed for 27 days using 6 different treatments. In addition to the controls, five vegetable waste mixtures (0.77 m3 each) were treated with different amounts of the SP additive, namely, 5%, 10%, 15%, 20% and 25%. The ammonia volatilization loss and greenhouse gas emissions were measured during composting. Results indicated that the SP additive significantly decreased the ammonia volatilization and greenhouse gas emissions during vegetable waste composting. The additive reduced the total NH3 emission by 4.0% to 16.7%. The total greenhouse gas emissions (CO2-eq) of all treatments with SP additives were decreased by 10.2% to 20.8%, as compared with the controls. The NH3 emission during vegetable waste composting had the highest contribution to the greenhouse effect caused by the four different gases. The amount of NH3 (CO2-eq) from each treatment ranged from 59.90 kg . t-1 to 81.58 kg . t-1; NH3(CO2-eq) accounted for 69% to 77% of the total emissions from the four gases. Therefore, SP is a cost-effective phosphorus-based fertilizer that can be used as an additive during vegetable waste composting to reduce the NH3 and greenhouse gas emissions as well as to improve the value of compost as a fertilizer.

  12. Different responses of alpine plants to nitrogen addition: effects on plant-plant interactions

    PubMed Central

    Wang, Jun; Luo, Peng; Yang, Hao; Mou, Chengxiang; Mo, Li

    2016-01-01

    The different responses of plant species to resource stress are keys to understand the dynamics of plant community in a changing environment. To test the hypothesis that nitrogen (N) increase would benefit N competitive species, rather than N stress-tolerant species, to compete with neighbours, we conducted an experiment with neighbour removal, N addition and soil moisture as treatments in an alpine grassland on the southeastern Tibetan Plateau. Both growths and competitive-response abilities (CRA, the ability to tolerate the inhibitory effects of neighbors) of Kobresia macrantha, Polygonum viviparum and Potentilla anserine in wet site were facilitated by N addition, conversely, both growths and CRA of Taraxacum mongolicum and Ligularia virgaurea were suppressed by N addition, indicating that the responses of CRA of target species under N addition were consistent with the N utilization strategies of them. Moreover, the facilitative effects of N addition on competitive-response abilities of Kobresia macrantha and Polygonum viviparum were not found at the dry site, illustrating that soil moisture can alter the changes of neighbour effects caused by N addition. Life strategy of dominant species in plant community on the undisturbed southeastern Tibetan Plateau may shift from N stress-tolerant to N competitive, if the N increases continuously. PMID:27922131

  13. Widespread non-additive and interaction effects within HLA loci modulate the risk of autoimmune diseases

    PubMed Central

    Lenz, Tobias L.; Deutsch, Aaron J.; Han, Buhm; Hu, Xinli; Okada, Yukinori; Eyre, Stephen; Knapp, Michael; Zhernakova, Alexandra; Huizinga, Tom W.J.; Abecasis, Goncalo; Becker, Jessica; Boeckxstaens, Guy E.; Chen, Wei-Min; Franke, Andre; Gladman, Dafna D.; Gockel, Ines; Gutierrez-Achury, Javier; Martin, Javier; Nair, Rajan P.; Nöthen, Markus M.; Onengut-Gumuscu, Suna; Rahman, Proton; Rantapää-Dahlqvist, Solbritt; Stuart, Philip E.; Tsoi, Lam C.; Van Heel, David A.; Worthington, Jane; Wouters, Mira M.; Klareskog, Lars; Elder, James T.; Gregersen, Peter K.; Schumacher, Johannes; Rich, Stephen S.; Wijmenga, Cisca; Sunyaev, Shamil R.; de Bakker, Paul I.W.; Raychaudhuri, Soumya

    2015-01-01

    Human leukocyte antigen (HLA) genes confer strong risk for autoimmune diseases on a log-additive scale. Here we speculated that differences in autoantigen binding repertoires between a heterozygote’s two expressed HLA variants may result in additional non-additive risk effects. We tested non-additive disease contributions of classical HLA alleles in patients and matched controls for five common autoimmune diseases: rheumatoid arthritis (RA, Ncases=5,337), type 1 diabetes (T1D, Ncases=5,567), psoriasis vulgaris (Ncases=3,089), idiopathic achalasia (Ncases=727), and celiac disease (Ncases=11,115). In four out of five diseases, we observed highly significant non-additive dominance effects (RA: P=2.5×1012; T1D: P=2.4×10−10; psoriasis: P=5.9×10−6; celiac disease: P=1.2×10−87). In three of these diseases, the dominance effects were explained by interactions between specific classical HLA alleles (RA: P=1.8×10−3; T1D: P=8.6×1027; celiac disease: P=6.0×10−100). These interactions generally increased disease risk and explained moderate but significant fractions of phenotypic variance (RA: 1.4%, T1D: 4.0%, and celiac disease: 4.1%, beyond a simple additive model). PMID:26258845

  14. The effects of nutrient additions on particulate and dissolved primary production in surface waters of three Mediterranean eddies

    NASA Astrophysics Data System (ADS)

    Lagaria, A.; Psarra, S.; Lefèvre, D.; van Wambeke, F.; Courties, C.; Pujo-Pay, M.; Oriol, L.; Tanaka, T.; Christaki, U.

    2010-12-01

    The effects of additions of nitrogen (+N), phosphorus (+P), alone and in combination, were assessed during three microcosm experiments performed with surface waters of three anticyclonic eddies, located in the Western, Central and Eastern Mediterranean. We examined the effects of nutrient additions on rates of dissolved and particulate primary production and on metabolic rates of the osmotrophic community (phytoplankton and heterotrophic prokaryotes). The experiments were performed in June/July 2008 during the BOUM (Biogeochemistry from the Oligotrophic to the Ultra-oligotrophic Mediterranean) cruise. In all three experiments, particulate primary production was significantly stimulated by the additions of nitrogen (+N, +NP) while no effect was observed with the addition of phosphorus alone. Percent extracellular release (PER) showed an inverse relation with total primary production (PPtotal), displaying the lowest values (4-8%) in the +NP treatment. Among the three treatments, the +NP had the strongest effect on the community metabolic rates leading to positive net community production values (NCP>0). These changes of NCP were mainly due to enhanced gross community production (GCP) rather than lower respiration rates (CR). In +NP treatments autotrophic production (whether expressed as GCP or PPtotal) was high enough to fulfil the carbon requirements of the heterotrophic prokaryotes, with phytoplankton and heterotrophic prokaryote production positively correlated. Addition of nitrogen alone (+N) had a smaller effect on community production, resulting in metabolically balanced systems (NCP≍0). Finally, heterotrophic conditions persisted in the +P treatment at the central and eastern stations, and gross production was not sufficient to supply bacterial carbon demand, evidence of a decoupling of phytoplankton production and consumption by heterotrophic prokaryotes.

  15. Main and interactive effects of depression and posttraumatic stress in relation to alcohol dependence among urban male firefighters.

    PubMed

    Paulus, Daniel J; Vujanovic, Anka A; Schuhmann, Bailee B; Smith, Lia J; Tran, Jana

    2017-05-01

    Depression, posttraumatic stress, and alcohol use are highly prevalent among firefighters. However, no study has evaluated the interactive effects of depression and posttraumatic stress with regard to alcohol use among firefighters. The current study examined main and interactive effects of depression and posttraumatic stress in terms of alcohol dependence symptoms, positive alcohol dependence screen, and drinks per occasion. Participants included 2707 male urban firefighters. There was a main effect of posttraumatic stress in relation to all alcohol-related outcomes and a main effect of depression only for alcohol dependence symptoms. There was a significant interaction of depression and posttraumatic stress with regard to symptoms of alcohol dependence, positive screen for alcohol dependence, and number of drinks per occasion. Interactions were evident above main effects and covariates (age, presence of a spouse/partner, tenure in the fire department, history of active duty in the U.S. armed forces, and racial/ethnic minority status). Overall, heightened depression was positively associated with alcohol-related outcomes for those with lower but not higher levels of posttraumatic stress in all models. Posttraumatic stress and depression may pose unique interactive risks for alcohol dependence in urban male firefighters. Implications for clinical intervention in firefighters are discussed.

  16. Additive Effect on Soybean Peroxidase-Catalyzed Removal of Anilines from Water

    PubMed Central

    Mazloum, Samar; Al-Ansari, Mohammed Mousa; Taylor, Keith; Bewtra, Jatinder K.; Biswas, Niharendu

    2016-01-01

    Abstract Soybean peroxidase has been shown to be effective in removal of aromatic compounds from wastewater, while the use of additives effectively reduces enzyme concentration requirement, hence overall treatment cost. Enzymatic treatment, an oxidative polymerization, was successful in removal of over 95% of both aniline and o-anisidine. The originality of this study lies in the findings that the additives, sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), Triton X-100, and sodium dodecanoate (SDOD), reduced enzyme concentration requirement, while polyethylene glycol (PEG, average molar mass of 3350 g/mol) had no effect on the required enzyme concentration. In addition, the presence of SDS also enhanced treatment by improving precipitation and color removal. These results are enabling advancement of soybean peroxidase-catalyzed treatment of anilines found in wastewaters as a new sustainable method. PMID:26989345

  17. [Effects of menthol as an additive in tobacco products and the need for regulation].

    PubMed

    Kahnert, S; Nair, U; Mons, U; Pötschke-Langer, M

    2012-03-01

    Menthol is the most widely used and the most prominent tobacco additive in tobacco products advertised and marketed by the tobacco industry. Besides its characteristic flavor, it possesses a variety of pharmacological properties facilitating tobacco smoke inhalation and potentiating dependence. These properties of menthol not only favor tobacco initiation and consumption but can also prevent smoking cessation. This article summarizes the effect of menthol as an additive in tobacco products and its effect on tobacco consumption that causes a number of chronic diseases and premature death and, therefore, counteracts tobacco control measures. Currently, there is no legislative regulation in Germany that considers the health hazard, addiction-enhancing and attractiveness-increasing properties of additives permitted in tobacco products. Effective regulation or even a ban could contribute to a reduction of tobacco consumption and, hence, save many people from a long-lasting tobacco dependence.

  18. Mechanisms and modeling of the effects of additives on the nitrogen oxides emission

    NASA Technical Reports Server (NTRS)

    Kundu, Krishna P.; Nguyen, Hung Lee; Kang, M. Paul

    1991-01-01

    A theoretical study on the emission of the oxides of nitrogen in the combustion of hydrocarbons is presented. The current understanding of the mechanisms and the rate parameters for gas phase reactions were used to calculate the NO(x) emission. The possible effects of different chemical species on thermal NO(x), on a long time scale were discussed. The mixing of these additives at various stages of combustion were considered and NO(x) concentrations were calculated; effects of temperatures were also considered. The chemicals such as hydrocarbons, H2, CH3OH, NH3, and other nitrogen species were chosen as additives in this discussion. Results of these calculations can be used to evaluate the effects of these additives on the NO(x) emission in the industrial combustion system.

  19. Effect of vermiculite addition on compost produced from Korean food wastes.

    PubMed

    Seo, J Y; Heo, J S; Kim, T H; Joo, W H; Crohn, D M

    2004-01-01

    To evaluate the effect of vermiculite addition on composting food wastes from Korean households, food wastes were composted in three small bins to which different additives were added. The following three bins were employed: in Case I, only recycled compost was composted; in Case II, food wastes with recycled compost; and in Case III, food wastes with recycled compost and vermiculite. In the experiment performed for 30 days, it was confirmed that the supplementary addition of vermiculite to the composting mixture did not significantly improve the weight loss rate and the decomposition rate of food wastes. Due to dilution through the use of inorganic vermiculite, the vermiculite addition reduced the organic matter concentration of the composting mixtures. Vermiculite addition did not raise the pH value. Weight losses of roughly 70% were observed based on calculating moisture loss as well as dry food waste loss and not considering additives, while dry food waste loss was 29.4% and 35.8% with and without the addition of vermiculite, respectively. For these experiments, the major portion of the weight loss was the loss of water. The results indicate a need to differentiate between weight loss percentages and decomposition percentages, and a need to indicate if either of these percentages includes or excludes the mass of additives.

  20. [Study on main pharmacodynamic effects for Schisandra lignans based upon network pharmacology].

    PubMed

    Qiu, Hong-tao; Zhao, Xiao-ping; Li, Zheng; Wang, Lin-li; Wang, Yi

    2015-02-01

    In this study, we focused on the study of pharmacodynamic effects for 6 major bioactive lignans of Schisandra chinensis, namely deoxyschizandrin, schisandrin B, schisandrin C, schisandrin, schizandrol B and schisantherin A. A compound-gene-pathway network, which contained 124 related genes and 88 pathways, was constructed by collecting drug genes through mining relevant literatures and network pharmacology analysis. Based on the network analysis, 32 pathways and 80 related genes were associated with inflammation, which implied that anti-inflammatory might be the major pharmacodynamic effects of these compounds. All lignans except schizandrol B reduced LPS-induced NO production in RAW264.7 cells, which validated the anti-inflammatory hypothesis generated from network analysis. Furthermore, we investigated the effects of deoxyschizandrin, schisandrin C, schisandrin and schisantherin A on the secretion of inflammatory cytokines TNF-α, IL-1β, IL-6, PGE2 and protein expressions of iNOS, COX-2. As a result, deoxyschizandrin showed the strongest anti-inflammatory activity with inhibitory effect on all 4 inflammatory cytokines secretions and protein expressions of iNOS, COX-2. This study provided evidences for systematic exploration on the pharmacolgical actions and mechanisms of schisandra.

  1. Does the model of additive effect in placebo research still hold true? A narrative review

    PubMed Central

    Berger, Bettina; Weger, Ulrich; Heusser, Peter

    2017-01-01

    Personalised and contextualised care has been turned into a major demand by people involved in healthcare suggesting to move toward person-centred medicine. The assessment of person-centred medicine can be most effectively achieved if treatments are investigated using ‘with versus without’ person-centredness or integrative study designs. However, this assumes that the components of an integrative or person-centred intervention have an additive relationship to produce the total effect. Beecher’s model of additivity assumes an additive relation between placebo and drug effects and is thus presenting an arithmetic summation. So far, no review has been carried out assessing the validity of the additive model, which is to be questioned and more closely investigated in this review. Initial searches for primary studies were undertaken in July 2016 using Pubmed and Google Scholar. In order to find matching publications of similar magnitude for the comparison part of this review, corresponding matches for all included reviews were sought. A total of 22 reviews and 3 clinical and experimental studies fulfilled the inclusion criteria. The results pointed to the following factors actively questioning the additive model: interactions of various effects, trial design, conditioning, context effects and factors, neurobiological factors, mechanism of action, statistical factors, intervention-specific factors (alcohol, caffeine), side-effects and type of intervention. All but one of the closely assessed publications was questioning the additive model. A closer examination of study design is necessary. An attempt in a more systematic approach geared towards solutions could be a suggestion for future research in this field. PMID:28321318

  2. Analysis of error-prone survival data under additive hazards models: measurement error effects and adjustments.

    PubMed

    Yan, Ying; Yi, Grace Y

    2016-07-01

    Covariate measurement error occurs commonly in survival analysis. Under the proportional hazards model, measurement error effects have been well studied, and various inference methods have been developed to correct for error effects under such a model. In contrast, error-contaminated survival data under the additive hazards model have received relatively less attention. In this paper, we investigate this problem by exploring measurement error effects on parameter estimation and the change of the hazard function. New insights of measurement error effects are revealed, as opposed to well-documented results for the Cox proportional hazards model. We propose a class of bias correction estimators that embraces certain existing estimators as special cases. In addition, we exploit the regression calibration method to reduce measurement error effects. Theoretical results for the developed methods are established, and numerical assessments are conducted to illustrate the finite sample performance of our methods.

  3. Effects of magma mingling in the granites of Mount Desert Island, Maine

    SciTech Connect

    Seaman, S.J.; Ramsey, P.C. )

    1992-07-01

    Textures and compositional relationships associated with dark-colored, fine-grained enclaves in the Cadillac Mountain and Somesville granites, Mount Desert Island, Maine, preserve abundant evidence for contamination of host granitic magmas by enclave liquids. Fine-grained enclaves, which apparently represent chilled magmatic droplets, have affected the composition and texture of the host granites by three possible mechanisms: (1) crystallization of feldspar-quartz-hornblende pegmatite pods from fluids of enclave origin in the granite surrounding enclaves, and the disaggregation of the pods and dispersion of crystals into the granite; (2) ionic exchange between enclaves and granitic magmas; (3) the generation around enclaves of rinds consisting of an inner alkali feldspar-quartz zone and an outer zone of hornblende-enriched granite. Thermal calculations suggest that the alkali feldspar-quartz zones of the rinds surrounding enclaves may result from resorption of alkali feldspar and quartz crystals in the granitic magma by heat of cooling and crystallization of enclave material. The interaction between the hot enclave and the alkali feldspar-quartz composition liquid may be analogous to that between a pluton and meteoric water in a hydrothermal system. The segregation of alkali feldspar-quartz and hornblende-rich zones may result from the minimum melt composition fluid migrating toward the enclave, leaving behind unmelted hornblende, as part of a convection circuit set up by the enclave. Alternatively, hornblende-rich zones concentric to and outside of the alkali feldspar-quartz rinds may record limit of movement of a front of hydrous fluid driven from the enclave boundary down a thermal gradient.

  4. Potential effects of climate change on the distribution range of the main silicate sinker of the Southern Ocean

    PubMed Central

    Pinkernell, Stefan; Beszteri, Bánk

    2014-01-01

    Fragilariopsis kerguelensis, a dominant diatom species throughout the Antarctic Circumpolar Current, is coined to be one of the main drivers of the biological silicate pump. Here, we study the distribution of this important species and expected consequences of climate change upon it, using correlative species distribution modeling and publicly available presence-only data. As experience with SDM is scarce for marine phytoplankton, this also serves as a pilot study for this organism group. We used the maximum entropy method to calculate distribution models for the diatom F. kerguelensis based on yearly and monthly environmental data (sea surface temperature, salinity, nitrate and silicate concentrations). Observation data were harvested from GBIF and the Global Diatom Database, and for further analyses also from the Hustedt Diatom Collection (BRM). The models were projected on current yearly and seasonal environmental data to study current distribution and its seasonality. Furthermore, we projected the seasonal model on future environmental data obtained from climate models for the year 2100. Projected on current yearly averaged environmental data, all models showed similar distribution patterns for F. kerguelensis. The monthly model showed seasonality, for example, a shift of the southern distribution boundary toward the north in the winter. Projections on future scenarios resulted in a moderately to negligibly shrinking distribution area and a change in seasonality. We found a substantial bias in the publicly available observation datasets, which could be reduced by additional observation records we obtained from the Hustedt Diatom Collection. Present-day distribution patterns inferred from the models coincided well with background knowledge and previous reports about F. kerguelensis distribution, showing that maximum entropy-based distribution models are suitable to map distribution patterns for oceanic planktonic organisms. Our scenario projections indicate

  5. [Effect of the incorporation of additives on the aging of corn starch gels and "arepas"].

    PubMed

    Rivero de Padua, M; Verde, O; Lucena de Orellana, M; Arias, J

    1988-12-01

    This research was carried out to investigate the effect of the incorporation of various additives on the ageing of corn starch and arepas. Starches were extracted from the endosperm of degerminated corn by a wet milling process, and its retrogradation, with or without the incorporation of additives was evaluated using the Brabender amilograph and by measuring the viscosity changes of the starch gels through time, using a Brookfield viscometer model RVT. The most effective additives in retarding the rate of ageing of starch gels, were used in the arepas. Likewise, trained panelists were utilized to find the levels of the additives incorporated in the arepas, by running taste threshold tests for each one of the additives. Textural changes of the arepas--maintained at two different storage temperatures, 9 degrees and 23 degrees C--were evaluated using an Instron texturometer. Preliminary tests with the corn starch allowed to choose the following additives: distilled monoglicerides, guar gum and hydrogenated vegetable oil. The effect of 15 different combinations of these additives on the texture of arepas was then studied, and findings revealed that only three of them were able to totally revert the retrogradation process, and maintain the hardness and elasticity within the expected range of a fresh-made arepa, when this is reheated until reaching a maximum temperature of 49 degrees C. A 66% of the hardening of the arepas prepared without additives can be reverted with the reheating process, but only if the product has not suffered dehydration. When stored for 24 hours at room temperature, unpacked arepas have a surface moisture loss of 47%, and even if reheated, hardening becomes irreversible in 84.6% of them.

  6. Effect of Ag, Ni and Bi Additions on Solderability of Lead-Free Solders

    NASA Astrophysics Data System (ADS)

    Nobari, Amir Hossein; Maalekian, Mehran; Seelig, Karl; Pekguleryuz, Mihriban

    2017-01-01

    In this study, the effects of Ag, Ni and Bi additions on the melting, solidification, fluidity and wetting behavior of Sn-0.7Cu base solder alloy are studied. The addition of a small amount of Ni reduces the undercooling and improves the feeding distance (fluidity length); however, Ni does not improve the wetting and the spreading performance. The effect of Ni on the fluidity length of Ag-containing Sn-0.7Cu (SAC alloy) is marginal. Bi and Ag both improve wetting performance and also lower the melting temperature; however, they do not improve the fluidity; instead, they reduce the maximum length of fluidity.

  7. Muonium Addition Reactions and Kinetic Isotope Effects in the Gas Phase: k∞ Rate Constants for Mu + C2H2.

    PubMed

    Arseneau, Donald J; Garner, David M; Reid, Ivan D; Fleming, Donald G

    2015-07-16

    The kinetics of the addition reaction of muonium (Mu) to acetylene have been studied in the gas phase at N2 moderator pressures mainly from ∼800 to 1000 Torr and over the temperature range from 168 to 446 K, but also down to 200 Torr at 168 K and over a much higher range of pressures, from 10 to 44 bar at 295 K, demonstrating pressure-independent rate constants, kMu(T). Even at 200 Torr moderator pressure, the kinetics for Mu + C2H2 addition behave as if effectively in the high-pressure limit, giving k∞ = kMu due to depolarization of the muon spin in the MuC2H2 radical formed in the addition step. The rate constants kMu(T) exhibit modest Arrhenius curvature over the range of measured temperatures. Comparisons with data and with calculations for the corresponding H(D) + C2H2 addition reactions reveal a much faster rate for the Mu reaction at the lowest temperatures, by 2 orders of magnitude, in accord with the propensity of Mu to undergo quantum tunneling. Moreover, isotopic atom exchange, which contributes in a major way to the analogous D atom reaction, forming C2HD + H, is expected to be unimportant in the case of Mu addition, a consequence of the much higher zero-point energy and hence weaker C-Mu bond that would form, meaning that the present report of the Mu + C2H2 reaction is effectively the only experimental study of kinetic isotope effects in the high-pressure limit for H-atom addition to acetylene.

  8. Dopaminergic, Serotonergic, and Oxytonergic Candidate Genes Associated with Infant Attachment Security and Disorganization? In Search of Main and Interaction Effects

    ERIC Educational Resources Information Center

    Luijk, Maartje P. C. M.; Roisman, Glenn I.; Haltigan, John D.; Tiemeier, Henning; Booth-LaForce, Cathryn; van IJzendoorn, Marinus H.; Belsky, Jay; Uitterlinden, Andre G.; Jaddoe, Vincent W. V.; Hofman, Albert; Verhulst, Frank C.; Tharner, Anne; Bakermans-Kranenburg, Marian J.

    2011-01-01

    Background and methods: In two birth cohort studies with genetic, sensitive parenting, and attachment data of more than 1,000 infants in total, we tested main and interaction effects of candidate genes involved in the dopamine, serotonin, and oxytocin systems ("DRD4", "DRD2", "COMT", "5-HTT", "OXTR") on attachment security and disorganization.…

  9. The effects of storms and storm-generated currents on sand beaches in Southern Maine, USA

    USGS Publications Warehouse

    Hill, H.W.; Kelley, J.T.; Belknap, D.F.; Dickson, S.M.

    2004-01-01

    Storms are one of the most important controls on the cycle of erosion and accretion on beaches. Current meters placed in shoreface locations of Saco Bay and Wells Embayment, ME, recorded bottom currents during the winter months of 2000 and 2001, while teams of volunteers profiled the topography of nearby beaches. Coupling offshore meteorological and beach profile data made it possible to determine the response of nine beaches in southern Maine to various oceanographic and meteorological conditions. The beaches selected for profiling ranged from pristine to completely developed and permitted further examination of the role of seawalls on the response of beaches to storms. Current meters documented three unique types of storms: frontal passages, southwest storms, and northeast storms. In general, the current meter results indicate that frontal passages and southwest storms were responsible for bringing sediment towards the shore, while northeast storms resulted in a net movement of sediment away from the beach. During the 1999-2000 winter, there were a greater percentage of frontal passages and southwest storms, while during the 2000-2001 winter, there were more northeast storms. The sediment that was transported landward during the 1999-2000 winter was reworked into the berm along moderately and highly developed beaches during the next summer. A northeast storm on March 5-6, 2001, resulted in currents in excess of 1 m s-1 and wave heights that reached six meters. The storm persisted over 10 high tides and caused coastal flooding and property damage. Topographic profiles made before and after the storm demonstrate that developed beaches experienced a loss of sediment volume during the storm, while sediment was redistributed along the profile on moderately developed and undeveloped beaches. Two months after the storm, the profiles along the developed beaches had not reached their pre-storm elevation. In comparison, the moderately developed and undeveloped beaches

  10. Demographic Characteristics of a Maine Woodcock Population and Effects of Habitat Management

    USGS Publications Warehouse

    Dwyer, T.J.; Sepik, G.F.; Derleth, E.L.; McAuley, D.G.

    1988-01-01

    A population of American woodcock (Scolopax minor) was studied on a 3,401-ha area of the Moosehorn National Wildlife Refuge in northeastern Maine from 1976 through 1985. During 1976-83, from 4 to 64 clearcuts were created each year, opening up large contiguous blocks of forest. A combination of mist nets, ground traps, nightlighting techniques, and trained dogs were used to capture and band 1,884 birds during the first 5 years. Capture and recapture data (totaling 3,009 observations) were used with both demographically closed and open population models to estimate population size and, for open population models, summer survival. Flying young, especially young males, represented the greatest proportion of all captures; analysis showed that young males were more prone to capture than young females. Male courtship began about 24 March each year, usually when there was still snow in wooded areas. Males ~2 years old dominated singing grounds during April each year, but this situation changed and first-year males dominated singing grounds in May. Singing males shifted from older established singing grounds to new clearcuts soon after we initiated forest management. Many males were subdominant at singing grounds despite an abundance of unoccupied openings. Three hundred adult females were captured and, except for 1978, the majority were ~2 years old. The year in which female homing rate was lowest(1979) was preceded by the year with the largest number of l-year-old brood female captures and a summer drought. Summer survival of young was lowest in 1978 and was attributed to summer drought. The year 1979 had an abnormally cool and wet spring, and was the poorest for production of young. Capture ratios of young-to-adult females obtained by nightlighting could be used to predict production on our study area. Closed population model estimates did not seem to fit either young or adult data sets well. Instead, a partially open capture-recapture model that allowed death but no

  11. Effect of Alloying Additions on Phase Equilibria and Creep Resistance of Alumina-Forming Austenitic Stainless Steels

    NASA Astrophysics Data System (ADS)

    Yamamoto, Y.; Santella, M. L.; Brady, M. P.; Bei, H.; Maziasz, P. J.

    2009-08-01

    The high-temperature creep properties of a series of alumina-forming austenitic (AFA) stainless steels based on Fe-20Ni-(12-14)Cr-(2.5-4)Al-(0.2-3.3)Nb-0.1C (weight percent) were studied. Computational thermodynamics were used to aid in the interpretation of data on microstructural stability, phase equilibria, and creep resistance. Phases of MC (M: mainly Nb), M23C6 (M: mainly Cr), B2 [ β-(Ni,Fe)Al], and Laves [Fe2(Mo,Nb)] were observed after creep-rupture testing at 750 °C and 170 MPa; this was generally consistent with the thermodynamic calculations. The creep resistance increased with increasing Nb additions up to 1 wt pct in the 2.5 and 3 Al wt pct alloy series, due to the stabilization of nanoscale MC particles relative to M23C6. Additions of Nb greater than 1 wt pct decreased creep resistance in the alloy series due to stabilization of the Laves phase and increased amounts of undissolved, coarse MC, which effectively reduced the precipitation of nanoscale MC particles. The additions of Al also increased the creep resistance moderately due to the increase in the volume fraction of B2 phase precipitates. Calculations suggested that optimum creep resistance would be achieved at approximately 1.5 wt pct Nb in the 4 wt pct Al alloy series.

  12. Effect of alloying additions on phase equilibria and creep resistance of alumina-forming austenitic stainless steels

    SciTech Connect

    Yamamoto, Yukinori; Santella, Michael L; Brady, Michael P; Bei, Hongbin; Maziasz, Philip J

    2009-01-01

    The high-temperature creep properties of a series of alumina-forming austenitic (AFA) stainless steels based on Fe-20Ni-(12-14)Cr-(2.5-4)Al-(0.2-3.3)Nb-0.1C (weight percent) were studied. Computational thermodynamics were used to aid in the interpretation of data on microstructural stability, phase equilibria, and creep resistance. Phases of MC (M: mainly Nb), M{sub 23}C{sub 6} (M: mainly Cr), B2 [{beta}-(Ni,Fe)Al], and Laves [Fe{sub 2}(Mo,Nb)] were observed after creep-rupture testing at 750 C and 170 MPa; this was generally consistent with the thermodynamic calculations. The creep resistance increased with increasing Nb additions up to 1 wt pct in the 2.5 and 3 Al wt pct alloy series, due to the stabilization of nanoscale MC particles relative to M{sub 23}C{sub 6}. Additions of Nb greater than 1 wt pct decreased creep resistance in the alloy series due to stabilization of the Laves phase and increased amounts of undissolved, coarse MC, which effectively reduced the precipitation of nanoscale MC particles. The additions of Al also increased the creep resistance moderately due to the increase in the volume fraction of B2 phase precipitates. Calculations suggested that optimum creep resistance would be achieved at approximately 1.5 wt pct Nb in the 4 wt pct Al alloy series.

  13. Effect of fluoride addition on the properties of dental alginate impression materials.

    PubMed

    Lee, Yong-Keun; Lim, Bum-Soon; Kim, Cheol-We

    2004-03-01

    Fluoride-containing dental alginate impression materials can exert a considerable reduction in enamel solubility. The objective was to evaluate the effects of fluoride addition in the alginate impression materials on the properties and subsequent release of fluoride. Four experimental alginate impression materials were studied. Materials were mixed with distilled water (control) or 100-ppm fluoride solution. One or two percent NaF, or 1% SnF2 was added to the materials, which were mixed with distilled water. Fluoride release, flexibility, recovery from deformation, setting time, compressive strength and elastic modulus were determined in accordance with the ISO 1563 and ANSI/ADA Spec. 18. Fluoride release increased after addition of fluoride, and the released amount was 0.762-14.761 ppm. Addition of NaF or SnF2 resulted in higher fluoride release than the control group (p < 0.05). After fluoride addition, flexibility was 15.45-20.27%, and the recovery from deformation did not change except one material. Compressive strength after fluoride addition was 0.36-1.12 MPa. Addition of NaF or SnF2 in an alginate impression material may result in effective release of fluoride without deteriorating the properties of material itself.

  14. Effects of silicon additions on the mechanical properties and microstructure of high speed steels

    SciTech Connect

    Pan, F.; Ding, P.; Zhou, S.; Kang, M.; Edmonds, D.V.

    1997-11-01

    The effects of silicon additions up to 3.5 wt% on the mechanical properties and microstructure of high speed steels 6W3Mo2Cr4V, W3Mo2Cr4V and W9Mo3Cr4V have been investigated. In order to understand these effects further, a Fe-16Mo-0.9C alloy is also used. The results show silicon additions can increase the temper hardness of steels Fe-16Mo-0.9C, 6W3Mo2Cr4V and W3Mo2Cr4V, bu yield an opposite influence on the temper hardness in W9Mo3Cr4V steels. A critical tempering temperature exists for the bending strength of high speed steels containing silicon. If tempering is carried out at temperatures lower than the critical temperature, the bending strength of the high speed steels can be improved by the addition of silicon, otherwise their bending strength is decreased. Transmission electron microscopy reveals that silicon additions can obviously refine secondary hardening carbides and inhibit the formation of M{sub 3}C cementite at peak temperature. However, they are also found to accelerate both the depletion of martensite and the formation of coarse M{sub 6}C precipitates during tempering. The mechanism whereby silicon additions affect the secondary hardness of high speed steels is discussed in detail, and the types of high speed steel in which silicon additions can be used are suggested.

  15. The effect of tailor-made additives on crystal growth of methyl paraben: Experiments and modelling

    NASA Astrophysics Data System (ADS)

    Cai, Zhihui; Liu, Yong; Song, Yang; Guan, Guoqiang; Jiang, Yanbin

    2017-03-01

    In this study, methyl paraben (MP) was selected as the model component, and acetaminophen (APAP), p-methyl acetanilide (PMAA) and acetanilide (ACET), which share the similar molecular structure as MP, were selected as the three tailor-made additives to study the effect of tailor-made additives on the crystal growth of MP. HPLC results indicated that the MP crystals induced by the three additives contained MP only. Photographs of the single crystals prepared indicated that the morphology of the MP crystals was greatly changed by the additives, but PXRD and single crystal diffraction results illustrated that the MP crystals were the same polymorph only with different crystal habits, and no new crystal form was found compared with other references. To investigate the effect of the additives on the crystal growth, the interaction between additives and facets was discussed in detail using the DFT methods and MD simulations. The results showed that APAP, PMAA and ACET would be selectively adsorbed on the growth surfaces of the crystal facets, which induced the change in MP crystal habits.

  16. Effects of Alternate Leading Edge Cutback on the Space Shuttle Main Engine Low Pressure Fuel Pump

    NASA Technical Reports Server (NTRS)

    Mulder, Andrew; Skelley, Stephen

    2016-01-01

    A higher order cavitation oscillation observed in the SSME low pressure fuel pump has been eliminated in water flow testing of a modified subscale replica of the inducer. The low pressure pump was modified by removing the outboard sections of two opposing blades of the four-bladed inducer, blending the "cutback" regions into the blades at the leading edge and tip, and removing material on the suction sides to decrease the exposed leading edge thickness. The leading edge tips of the cutback blades were moved approximately 25 degrees from their previous locations, thereby increasing one blade to blade spacing, decreasing the second, while simultaneously moving the cutback tips downstream. The test was conducted in MSFC's inducer test loop at scaled operating conditions in degassed and filtered water. In addition to eliminating HOC across the entire scaled operating regime, rotating cavitation was suppressed while the range of both alternate blade and asymmetric cavitation were increased. These latter phenomena, and more significantly, the shifts between these cavitation modes also resulted in significant changes to the head coefficient at low cavitation numbers. Reverse flow was detected at a slightly larger flow coefficient with the cutback inducer and suction capability was reduced by approximately 1 velocity head at and above approximately 90% of the reference flow coefficient. These performance changes along with more intense reverse flow are consistent with poor flow area management and increased incidence in the cutback region. Although the test demonstrated that the inducer modification was successful at eliminating the higher order cavitation across the entire scaled operating regime, different, previously unobserved, cavitation oscillations were introduced and significant performance penalties were imposed.

  17. Dissociating compatibility effects and distractor costs in the additional singleton paradigm.

    PubMed

    Folk, Charles L

    2013-01-01

    The interpretation of identity compatibility effects associated with irrelevant items outside the nominal focus of attention has fueled much of the debate over early versus late selection and perceptual load theory. However, compatibility effects have also played a role in the debate over the extent to which the involuntary allocation of spatial attention (i.e., attentional capture) is completely stimulus-driven or whether it is contingent on top-down control settings. For example, in the context of the additional singleton paradigm, irrelevant color singletons have been found to produce not only an overall cost in search performance but also significant compatibility effects. This combination of search costs and compatibility effects has been taken as evidence that spatial attention is indeed allocated in a bottom-up fashion to the salient but irrelevant singletons. However, it is possible that compatibility effects in the additional singleton paradigm reflect parallel processing of identity associated with low perceptual load rather than an involuntary shift of spatial attention. In the present experiments, manipulations of load were incorporated into the traditional additional singleton paradigm. Under low-load conditions, both search costs and compatibility effects were obtained, replicating previous studies. Under high-load conditions, search costs were still present, but compatibility effects were eliminated. This dissociation suggests that the costs associated with irrelevant singletons may reflect filtering processes rather than the allocation of spatial attention.

  18. [The workplace-based learning: a main paradigm of an effective continuing medical education].

    PubMed

    Lelli, Maria Barbara

    2010-01-01

    On the strength of the literature analysis and the Emilia-Romagna Region experience, we suggest a reflection on the workplace-based learning that goes beyond the analysis of the effectiveness of specific didactic methodologies and aspects related to Continuing Medical Education. Health education and training issue is viewed from a wider perspective, that integrates the three learning dimensions (formal, non formal and informal). In such a perspective the workplace-based learning becomes an essential paradigm to reshape the explicit knowledge conveyed in formal context and to emphasize informal contexts where innovation is generated.

  19. Additive Effects on Si3n4 Oxidation/Volatilization in Water Vapor

    NASA Technical Reports Server (NTRS)

    Opila, Elizabeth J.; Robinson, R. Craig; Fox, Dennis S.; Wenglarz, Richard A.; Ferber, Mattison K.

    2002-01-01

    Two commercially available additive-containing silicon nitride materials were exposed in four environments which range in severity from dry oxygen at 1 atm pressure, and low gas velocity to an actual turbine engine. Oxidation and volatilization kinetics were monitored at temperatures ranging from 1066 to 1400 C. The main purpose of this paper is to examine the surface oxide morphology resulting from the exposures. It was found that the material surface was enriched in rare earth silicate phases in combustion environments when compared to the oxides formed on materials exposed in dry oxygen. However, the in situ formation of rare earth disilicate phases offered little additional protection from the volatilization of silica observed in combustion environments. It was concluded that externally applied environmental barrier coatings are needed to protect additive-containing silicon nitride materials from volatilization reactions in combustion environments. Introduction Si3N4 is proposed for use as components, such as vanes, in turbine applications. Tens of thousands of hours of life are needed for both land-based turbines and aeropropulsion applications. Additive-containing SisN4 materials are

  20. Effect of organometallic fuel additives on nanoparticle emissions from a gasoline passenger car.

    PubMed

    Gidney, Jeremy T; Twigg, Martyn V; Kittelson, David B

    2010-04-01

    Particle size measurements were performed on the exhaust of a car operating on a chassis dynamometer fueled with standard gasoline and gasoline containing low levels of Pb, Fe, and Mn organometallic additives. When additives were present there was a distinct nucleation mode consisting primarily of sub-10 nm nanoparticles. At equal molar dosing Mn and Fe gave similar nanoparticle concentrations at the tailpipe, whereas Pb gave a considerably lower concentration. A catalytic stripper was used to remove the organic component of these particles and revealed that they were mainly solid and, because of their association with inorganic additives, presumably inorganic. Solid nucleation mode nanoparticles of similar size and concentration to those observed here from a gasoline engine with Mn and Fe additives have also been observed from modern heavy-duty diesel engines without aftertreatment at idle, but these solid particles are a small fraction of the primarily volatile nucleation mode particles emitted. The solid nucleation mode particles emitted by the diesel engines are likely derived from metal compounds in the lubrication oil, although carbonaceous particles cannot be ruled out. Significantly, most of these solid nanoparticles emitted by both engine types fall below the 23 nm cutoff of the PMP number regulation.

  1. The effect of lactic acid bacterial starter culture and chemical additives on wilted rice straw silage.

    PubMed

    Wang, Yan-Su; Shi, Wei; Huang, Lin-Ting; Ding, Cheng-Long; Dai, Chuan-Chao

    2016-04-01

    Lactic acid bacteria (LAB) are suitable for rice straw silage fermentation, but have been studied rarely, and rice straw as raw material for ensiling is difficult because of its disadvantages, such as low nutrition for microbial activities and low abundances of natural populations of LAB. So we investigated the effect of application of LAB and chemical additives on the fermentation quality and microbial community of wilted rice straw silage. Treatment with chemical additives increased the concentrations of crude protein (CP), water soluble carbohydrate (WSC), acetic acid and lactic acid, reduced the concentrations of acid detergent fiber (ADF) and neutral detergent fiber (NDF), but did not effectively inhibit the growth of spoilage organisms. Inoculation with LABs did not improve the nutritional value of the silage because of poor growth of LABs in wilted rice straw. Inoculation with LAB and addition of chemical materials improved the quality of silage similar to the effects of addition of chemical materials alone. Growth of aerobic and facultatively anaerobic bacteria was inhibited by this mixed treatment and the LAB gradually dominated the microbial community. In summary, the fermentation quality of wilted rice straw silage had improved by addition of LAB and chemical materials.

  2. Genome scan for nonadditive heterotic trait loci reveals mainly underdominant effects in Saccharomyces cerevisiae.

    PubMed

    Laiba, Efrat; Glikaite, Ilana; Levy, Yael; Pasternak, Zohar; Fridman, Eyal

    2016-04-01

    The overdominant model of heterosis explains the superior phenotype of hybrids by synergistic allelic interaction within heterozygous loci. To map such genetic variation in yeast, we used a population doubling time dataset of Saccharomyces cerevisiae 16 × 16 diallel and searched for major contributing heterotic trait loci (HTL). Heterosis was observed for the majority of hybrids, as they surpassed their best parent growth rate. However, most of the local heterozygous loci identified by genome scan were surprisingly underdominant, i.e., reduced growth. We speculated that in these loci adverse effects on growth resulted from incompatible allelic interactions. To test this assumption, we eliminated these allelic interactions by creating hybrids with local hemizygosity for the underdominant HTLs, as well as for control random loci. Growth of hybrids was indeed elevated for most hemizygous to HTL genes but not for control genes, hence validating the results of our genome scan. Assessing the consequences of local heterozygosity by reciprocal hemizygosity and allele replacement assays revealed the influence of genetic background on the underdominant effects of HTLs. Overall, this genome-wide study on a multi-parental hybrid population provides a strong argument against single gene overdominance as a major contributor to heterosis, and favors the dominance complementation model.

  3. Growth hormone insensitivity syndrome (Laron syndrome): main characteristics and effects of IGF1 treatment.

    PubMed

    Carel, J C; Chaussain, J L; Chatelain, P; Savage, M O

    1996-07-01

    Growth hormone (GH) insensitivity is a pathological state characterized by a disturbance of the physiological relationship between GH secretion, synthesis of insulin-like growth-factor I (IGF-1) and the biological actions of GH. Laron syndrome, the prototype for GH insensitivity, is most often due to GH receptor deficiency. However, this syndrome is heterogeneous in terms of growth characteristics, bio-chemical features and, most importantly, genetic defects. Recent data have indicated that partial GH receptor deficiency could be involved in children with apparently idiopathic short stature. Laron syndrome, because of extreme growth deficiency and a lack of alternative treatment, was the first clinical situation in which recombinant human IGF-1 was used. IGF-1 accelerates growth rate in most patients, induces subtle modifications of the craniofacies and decreases fat mass. However, it is still too early to evaluate the long-term effects of IGF-1 on final height. Tolerance to the drug has been excellent in all reported trials. The major (but rare) side effects are transient intracranial hypertension and hypokalemia. Generalization of data obtained in Laron syndrome to other clinical situations should take account of the profound alterations in IGF-1 pharmacokinetics resulting from a deficiency in IGF-binding proteins.

  4. Effect of Fuel Additives on Spray Performance of Alternative Jet Fuels

    NASA Astrophysics Data System (ADS)

    Kannaiyan, Kumaran; Sadr, Reza

    2015-11-01

    Role of alternative fuels on reducing the combustion pollutants is gaining momentum in both land and air transport. Recent studies have shown that addition of nanoscale metal particles as fuel additives to liquid fuels have a positive effect not only on their combustion performance but also in reducing the pollutant formation. However, most of those studies are still in the early stages of investigation with the addition of nanoparticles at low weight percentages. Such an addition can affect the hydrodynamic and thermo-physical properties of the fuel. In this study, the near nozzle spray performance of gas-to-liquid jet fuel with and without the addition of alumina nanoparticles are investigated at macro- and microscopic levels using optical diagnostic techniques. At macroscopic level, the addition of nanoparticles is seen to enhance the sheet breakup process when compared to that of the base fuel. Furthermore, the microscopic spray characteristics such as droplet size and velocity are also found to be affected. Although the addition of nanoscale metal particles at low weight percentages does not affect the bulk fluid properties, the atomization process is found to be affected in the near nozzle region. Funded by Qatar National Research Fund.

  5. Effect of fructo-oligosaccharide and isomalto-oligosaccharide addition on baking quality of frozen dough.

    PubMed

    Park, Eun Young; Jang, Sung-Bum; Lim, Seung-Taik

    2016-12-15

    The baking quality of frozen doughs containing different levels of fructo-oligosaccharides (FO) or isomalto-oligosaccharides (IMO) (3-9%, w/w flour), and stored for 0-8weeks at -18°C, was examined. The addition of FO or IMO increased the proof volume of the dough and the loaf volume of bread prepared from frozen dough. A 6% addition of FO or IMO was optimum, giving the highest proof volume and bread loaf volume, but a higher concentration than 6% induced low baking quality including lower proof volume and bread loaf volume. The bread crumb was moister and softer after the addition of FO or IMO before, and even after, frozen storage. Darker crumb colour was observed in the bread after the addition of FO or IMO. The oligosaccharides added to the frozen dough were effective in improving the quality of bread made from frozen dough, except for resulting in a darker bread crumb.

  6. Assessment of additive/nonadditive effects in structure-activity relationships: implications for iterative drug design.

    PubMed

    Patel, Yogendra; Gillet, Valerie J; Howe, Trevor; Pastor, Joaquin; Oyarzabal, Julen; Willett, Peter

    2008-12-11

    Free-Wilson (FW) analysis is common practice in medicinal chemistry and is based on the assumption that the contributions to activity made by substituents at different substitution positions are additive. We analyze eight near complete combinatorial libraries assayed on several different biological response(s) (GPCR, ion channel, kinase and P450 targets) and show that only half-exhibit clear additive behavior, which leads us to question the concept of additivity that is widely taken for granted in drug discovery. Next, we report a series of retrospective experiments in which subsets are extracted from the libraries for FW analysis to determine the minimum attributes (size, distribution of substituents, and activity range) necessary to reach the same conclusion about additive/nonadditive effects. These attributes can provide guidelines on when it is appropriate to apply FW analysis as well as for library design, and they also have important implications for further steps in iterative drug design.

  7. Effects of mineral additions on durability and physico-mechanical properties of mortar

    NASA Astrophysics Data System (ADS)

    Logbi, A.; Kriker, A.; Snisna, Z.

    2017-02-01

    This paper consists of an experimental study of the effect of some mineral admixtures on the properties of mortar. Blast furnace Slag of El-Hadjar, natural pozzolan of Beni saf and limestone of Ghardaia, all from Algeria, are crushed in high fineness and incorporated in the cement with different contents (15 % 20 % and 10%) respectively, in order to perform the physico-mechanical characteristics and durability of the mortar. The replacement of cement by 15% of natural pozzolan, or 20% of the Blast furnace Slag improves the mechanical performances of mortar in early and long ages than the mortar without additions, but 10% of limestone fillers have a positive effect only at early age. For durability the three additions have developed a beneficial effect on mechanical resistance under the free aquifers water, while their effects are different on capillary absorption.

  8. Testcross additive and dominance effects in best linear unbiased prediction of maize single-cross performance.

    PubMed

    Bernardo, R

    1996-11-01

    Best linear unbiased prediction (BLUP) has been found to be useful in maize (Zea mays L.) breeding. The advantage of including both testcross additive and dominance effects (Intralocus Model) in BLUP, rather than only testcross additive effects (Additive Model), has not been clearly demonstrated. The objective of this study was to compare the usefulness of Intralocus and Additive Models for BLUP of maize single-cross performance. Multilocation data from 1990 to 1995 were obtained from the hybrid testing program of Limagrain Genetics. Grain yield, moisture, stalk lodging, and root lodging of untested single crosses were predicted from (1) the performance of tested single crosses and (2) known genetic relationships among the parental inbreds. Correlations between predicted and observed performance were obtained with a delete-one cross-validation procedure. For the Intralocus Model, the correlations ranged from 0.50 to 0.66 for yield, 0.88 to 0.94 for moisture, 0.47 to 0.69 for stalk lodging, and 0.31 to 0.45 for root lodging. The BLUP procedure was consistently more effective with the Intralocus Model than with the Additive Model. When the Additive Model was used instead of the Intralocus Model, the reductions in the correlation were largest for root lodging (0.06-0.35), smallest for moisture (0.00-0.02), and intermediate for yield (0.02-0.06) and stalk lodging (0.02-0.08). The ratio of dominance variance (v D) to total genetic variance (v G) was highest for root lodging (0.47) and lowest for moisture (0.10). The Additive Model may be used if prior information indicates that VD for a given trait has little contribution to VG. Otherwise, the continued use of the Intralocus Model for BLUP of single-cross performance is recommended.

  9. Effects of Ga Addition on Interfacial Reactions Between Sn-Based Solders and Ni

    NASA Astrophysics Data System (ADS)

    Wang, Chao-Hong; Li, Kuan-Ting

    2016-12-01

    The use of Ga as a micro-alloying element in Sn-based solders can change the microstructure of solder joints to improve the mechanical properties, and even suppress the interfacial intermetallic compound (IMC) growth. This research investigated the effects of Ga addition (0.2-1 wt.%Ga) on the IMC formation and morphological evolution in the Sn-based solder joints with Ni substrate. In the soldering reaction at 250°C and with less than 0.2 wt.%Ga addition, the formed phase was Ni3Sn4. When the Ga addition increased to 0.5 wt.%, it changed to a thin Ni2Ga3 layer of ˜1 μm thick, which stably existed at the interface in the initial 1-h reaction. Subsequently, the whole Ni2Ga3 layer detached from the Ni substrate and drifted into the molten solder. The Ni3Sn4 phase became dominant in the later stage. Notably, the Ga addition significantly reduced the grain size of Ni3Sn4, resulting in the massive spalling of Ni3Sn4 grains. With 1 wt.%Ga addition, the Ni2Ga3 layer remained very thin with no significant growth, and it stably existed at the interface for more than 10 h. In addition, the solid-state reactions were examined at temperatures of 160°C to 200°C. With addition of 0.5 wt.%Ga, the Ni3Sn4 phase dominated the whole reaction. By contrast, with increasing to 1 wt.%Ga, only a thin Ni2Ga3 layer was found even after aging at 160°C for more than 1200 h. The 1 wt.%Ga addition in solder can effectively inhibit the Ni3Sn4 formation in soldering and the long-term aging process.

  10. The effect of additive compounds on glycerol-induced damage to human chondrocytes.

    PubMed

    Hahn, Joshua; Laouar, Leila; Elliott, Janet A W; Korbutt, Gregory S; Jomha, Nadr M

    2017-04-01

    High concentrations of cryoprotective agents are required for cryopreservation techniques such as vitrification. Glycerol is a common cryoprotective agent used in cryopreservation protocols but this agent is toxic at high concentrations. This work is an attempt to mitigate the toxic effects of high concentrations of glycerol on intact chondrocytes in human knee articular cartilage from total knee arthroplasty patients by simultaneous exposure to glycerol and a variety of additive compounds. The resulting cell viability in the cartilage samples as measured by membrane integrity staining showed that, in at least one concentration or in combination, all of the tested additive compounds (tetramethylpyrazine, ascorbic acid, chondroitin sulphate, glucosamine sulphate) were able to reduce the deleterious effects of glycerol exposure when examination of membrane integrity took place on a delayed time frame. The use of additive compounds to reduce cryoprotectant toxicity in articular cartilage may help improve cell recovery after cryopreservation.

  11. Effects of magnesium chloride and organic additives on the synthesis of aragonite precipitated calcium carbonate

    NASA Astrophysics Data System (ADS)

    Park, Woon Kyoung; Ko, Sang-Jin; Lee, Seung Woo; Cho, Kye-Hong; Ahn, Ji-Whan; Han, Choon

    2008-05-01

    The synthesis of aragonite precipitated calcium carbonate by treating a suspension of Ca(OH) 2 with CO 2 gas was investigated with regard to the effects of Mg 2+ ions and organic additives on polymorphism and alternative orientations. In the presence of a small amount of Mg 2+, Mg-calcite formed, but as the Mg 2+ ion concentration increased, the amount of Mg-calcite decreased and the amount of aragonite increased. Thus, the formation of Mg-calcite is suppressed and only aragonite is formed in the presence of 60 mol% MgCl 2. As the Mg 2+ ion concentration increased, the aragonite that formed was found to have decreased in terms of its longitude and aspect ratio. Furthermore, the effect of Mg 2+ ions in conjunction with organic additives was also investigated with regard to polymorphs and morphology and the structure-forming properties of the organic additives.

  12. Probabilistic accident consequence uncertainty analysis -- Late health effects uncertainty assessment. Volume 1: Main report

    SciTech Connect

    Little, M.P.; Muirhead, C.R.; Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M.; Harper, F.T.; Hora, S.C.

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA late health effects models.

  13. Probabilistic accident consequence uncertainty analysis -- Early health effects uncertainty assessment. Volume 1: Main report

    SciTech Connect

    Haskin, F.E.; Harper, F.T.; Goossens, L.H.J.; Kraan, B.C.P.; Grupa, J.B.

    1997-12-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA early health effects models.

  14. [The real-world effectiveness of personal protective equipment and additional risks for workers' health].

    PubMed

    Denisov, É I; Morozova, T V; Adeninskaia, E E; Kur'erov, N N

    2013-01-01

    The effectiveness of personal protective equipment (PPE) of hearing, respiratory organs and hands is considered. It is shown that real effect of PPE is twice lower than declared by supplier; this presumes some derating system. The aspects of discomfort and additional risks are analyzed. The hygienic and physiologic evaluation of PPE is required along with elaboration of an official document (OSH standard or sanitary regulation) on selection, personal fit, organization of use and individual training of workers and their motivation.

  15. Main and interactive effects of arsenic and selenium on mallard reproduction and duckling growth and survival

    USGS Publications Warehouse

    Stanley, T.R.; Spann, J.W.; Smith, G.J.; Rosscoe, R.

    1994-01-01

    Arsenic (As) and selenium (Se) occur together in high concentrations in the environment and can accumulate in aquatic plants and invertebrates consumed by waterfowl. Ninety-nine pairs of breeding mallards (Anas platyrhynchos) were fed diets supplemented with As (sodium arsenate) at 0, 25, 100, or 400 ug/g, in combination with Se (seleno-DL-methionine) at 0 or 10 ug/g, in a replicated factorial experiment. Ducklings produced were placed on the same treatment combination as their parents. Arsenic accumulated in adult liver and egg, reduced adult weight gain and liver weight, delayed the onset of egg laying, decreased whole egg weight, and caused eggshell thinning. Arsenic did not affect hatching success and was not teratogenic. In ducklings, As accumulated in the liver and reduced body weight, growth, and liver weight. Arsenic did not increase duckling mortality, but it did decrease overall duckling production. Selenium accumulated in adult liver and egg, was teratogenic, and decreased hatching success. Selenium did not affect adult weight, liver weight, survival, onset of egg laying, egg fertility, egg weight, or eggshell thickness. In ducklings, Se accumulated in the liver and reduced body weight and growth, and increased liver weight. Selenium increased duckling mortality and decreased overall duckling production. Antagonistic interactions between As and Se occurred whereby As reduced Se accumulation in liver and egg, and alleviated the effects of Se on hatching success and embryo deformities. It was demonstrated that As and Se, in the chemical forms and at the dietary levels administered in this study, can adversely affect mallard reproduction and duckling growth and survival, and that As can alleviate toxic effects of Se.

  16. The Effectiveness of an Additional Stretching Exercise Program in Improving Flexibility Level among Preschool Boys

    ERIC Educational Resources Information Center

    Lee, Wee Akina Sia Seng; Rengasamy, Shabeshan A/L; Raju, Subramaniam A/L

    2014-01-01

    This study was conducted to examine the effectiveness of a two minutes' additional stretching exercise program in a 30 minutes games teaching lesson in improving the flexibility level of 6 year old preschool boys (M = 5.92, SD = 0.27) in a preschool in Malaysia. Fifty (50) preschool boys were selected for the study based on the intact sampling…

  17. Ontogeny of additive and maternal genetic effects: lessons from domestic mammals.

    PubMed

    Wilson, Alastair J; Reale, Denis

    2006-01-01

    Evolution of size and growth depends on heritable variation arising from additive and maternal genetic effects. Levels of heritable (and nonheritable) variation might change over ontogeny, increasing through "variance compounding" or decreasing through "compensatory growth." We test for these processes using a meta-analysis of age-specific weight traits in domestic ungulates. Generally, mean standardized variance components decrease with age, consistent with compensatory growth. Phenotypic convergence among adult sheep occurs through decreasing environmental and maternal genetic variation. Maternal variation similarly declines in cattle. Maternal genetic effects are thus reduced with age (both in absolute and relative terms). Significant trends in heritability (decreasing in cattle, increasing in sheep) result from declining maternal and environmental components rather than from changing additive variation. There was no evidence for increasing standardized variance components. Any compounding must therefore be masked by more important compensatory processes. While extrapolation of these patterns to processes in natural population is difficult, our results highlight the inadequacy of assuming constancy in genetic parameters over ontogeny. Negative covariance between direct and maternal genetic effects was common. Negative correlations with additive and maternal genetic variances indicate that antagonistic pleiotropy (between additive and maternal genetic effects) may maintain genetic variance and limit responses to selection.

  18. Thermodynamic method of calculating the effect of alloying additives on interphase interaction in composite materials

    NASA Technical Reports Server (NTRS)

    Tuchinsky, L. I.

    1986-01-01

    The effect of alloying additives to the matrix of a composite on the high temperature solubility rate of a single component fiber was analyzed thermodynamically. With an example of binary Ni alloys, with Group IV-VI transition metals reinforced with W fibers, agreement between the calculated and experimental data was demonstrated.

  19. 20 CFR 725.309 - Additional claims; effect of a prior denial of benefits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Additional claims; effect of a prior denial of benefits. 725.309 Section 725.309 Employees' Benefits EMPLOYMENT STANDARDS ADMINISTRATION, DEPARTMENT OF LABOR FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, AS AMENDED CLAIMS FOR BENEFITS...

  20. Additive Effects of Stimulus Quality and Word Frequency on Eye Movements during Chinese Reading

    ERIC Educational Resources Information Center

    Liu, Pingping; Li, Xingshan; Han, Buxin

    2015-01-01

    Eye movements of Chinese readers were recorded for sentences in which high- and low-frequency target words were presented normally or with reduced stimulus quality in two experiments. We found stimulus quality and word frequency produced strong additive effects on fixation durations for target words. The results demonstrate that stimulus quality…

  1. The Effect of Enzyme Addition on Anaerobic Digestion of Jose Tall Wheat Grass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of the addition of enzyme products containing cellulase, hemicellulase, and Beta-glucosidase to anaerobic digestion systems were studied. Anaerobic digestion tests were performed using batch reactors operated at 35°C. The application of enzyme products in three digestion configurations w...

  2. 20 CFR 410.535 - Reductions; effect of an additional claim for benefits.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Reductions; effect of an additional claim for benefits. 410.535 Section 410.535 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, TITLE IV-BLACK LUNG BENEFITS (1969- ) Payment of Benefits §...

  3. 20 CFR 410.535 - Reductions; effect of an additional claim for benefits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Reductions; effect of an additional claim for benefits. 410.535 Section 410.535 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH AND SAFETY ACT OF 1969, TITLE IV-BLACK LUNG BENEFITS (1969- ) Payment of Benefits §...

  4. Additive protective effects of the addition of lactic acid and adrenaline on excitability and force in isolated rat skeletal muscle depressed by elevated extracellular K+

    PubMed Central

    de Paoli, Frank Vincenzo; Overgaard, Kristian; Pedersen, Thomas Holm; Nielsen, Ole Bækgaard

    2007-01-01

    During strenuous exercise, extracellular K+ ([K+]o) is increased, which potentially can reduce muscle excitability and force production. In addition, exercise leads to accumulation of lactate and H+ and increased levels of circulating catecholamines. Individually, reduced pH and increased catecholamines have been shown to counteract the depressing effect of elevated K+. This study examines (i) whether the effects of addition of lactic acid and adrenaline on the excitability of isolated muscles are caused by separate mechanisms and are additive and (ii) whether the effect of adding lactic acid or increasing CO2 is related to a reduction of intra- or extracellular pH. Rat soleus muscles were incubated at a [K+]o of 15 mm, which reduced tetanic force by 85%. Subsequent addition of 20 mm lactic acid or 10−5m adrenaline led to a small recovery of force, but when added together induced an almost complete force recovery. Compound action potentials showed that the force recovery was associated with recovery of muscle excitability. The improved excitability after addition of adrenaline was associated with increased Na+–K+ pump activity resulting in hyperpolarization and an increase in the chemical Na+ gradient. In contrast, addition of lactic acid had no effect on the membrane potential or the Na+–K+ pump activity, but most likely increased excitability via a reduction in intracellular pH. It is concluded that the protective effects of acidosis and adrenaline on muscle excitability and force took place via different mechanisms and were additive. The results suggest that circulating catecholamines and development of acidosis during exercise may improve the tolerance of muscles to elevated [K+]o. PMID:17347268

  5. Additive protective effects of the addition of lactic acid and adrenaline on excitability and force in isolated rat skeletal muscle depressed by elevated extracellular K+.

    PubMed

    de Paoli, Frank Vincenzo; Overgaard, Kristian; Pedersen, Thomas Holm; Nielsen, Ole Baekgaard

    2007-06-01

    During strenuous exercise, extracellular K(+) ([K(+)](o)) is increased, which potentially can reduce muscle excitability and force production. In addition, exercise leads to accumulation of lactate and H(+) and increased levels of circulating catecholamines. Individually, reduced pH and increased catecholamines have been shown to counteract the depressing effect of elevated K(+). This study examines (i) whether the effects of addition of lactic acid and adrenaline on the excitability of isolated muscles are caused by separate mechanisms and are additive and (ii) whether the effect of adding lactic acid or increasing CO(2) is related to a reduction of intra- or extracellular pH. Rat soleus muscles were incubated at a [K(+)](o) of 15 mM, which reduced tetanic force by 85%. Subsequent addition of 20 mM lactic acid or 10(-5) M adrenaline led to a small recovery of force, but when added together induced an almost complete force recovery. Compound action potentials showed that the force recovery was associated with recovery of muscle excitability. The improved excitability after addition of adrenaline was associated with increased Na(+)-K(+) pump activity resulting in hyperpolarization and an increase in the chemical Na(+) gradient. In contrast, addition of lactic acid had no effect on the membrane potential or the Na(+)-K(+) pump activity, but most likely increased excitability via a reduction in intracellular pH. It is concluded that the protective effects of acidosis and adrenaline on muscle excitability and force took place via different mechanisms and were additive. The results suggest that circulating catecholamines and development of acidosis during exercise may improve the tolerance of muscles to elevated [K(+)](o).

  6. Effects of Litter and Nutrient Additions on Soil Carbon Cycling in a Tropical Forest

    NASA Astrophysics Data System (ADS)

    Cusack, D. F.; Halterman, S.; Turner, B. L.; Tanner, E.; Wright, S. J.

    2014-12-01

    Soil carbon (C) dynamics present one of the largest sources of uncertainty in global C cycle models, with tropical forest soils containing some of the largest terrestrial C stocks. Drastic changes in soil C storage and loss are likely to occur if global change alters plant net primary production (NPP) and/or nutrient availability in these ecosystems. We assessed the effects of litter removal and addition, as well as fertilization with nitrogen (N), phosphorus (P), and/or potassium (K), on soil C stocks in a tropical seasonal forest in Panama after ten and sixteen years, respectively. We used a density fractionation scheme to assess manipulation effects on rapidly and slowly cycling pools of C. Soil samples were collected in the wet and dry seasons from 0-5 cm and 5-10 cm depths in 15- 45x45 m plots with litter removal, 2x litter addition, and control (n=5), and from 32- 40x40 m fertilization plots with factorial additions of N, P, and K. We hypothesized that litter addition would increase all soil C fractions, but that the magnitude of the effect on rapidly-cycling C would be dampened by a fertilization effect. Results for the dry season show that the "free light" C fraction, or rapidly cycling soil C pool, was significantly different among the three litter treatments, comprising 5.1 ± 0.9 % of total soil mass in the litter addition plots, 2.7 ± 0.3 % in control plots, and 1.0 ± 0.1 % in litter removal plots at the 0-5cm depth (means ± one standard error, p < 0.05). Bulk soil C results are similar to observed changes in the rapidly cycling C pool for the litter addition and removal. Fertilization treatments on average diminished this C pool size relative to control plots, although there was substantial variability among fertilization treatments. In particular, addition of N and P together did not significantly alter rapidly cycling C pool sizes (4.1 ± 1.2 % of total soil mass) relative to controls (3.5 ± 0.4 %), whereas addition of P alone resulted in

  7. The distribution of salinity and main forcing effects in the Berre lagoon

    NASA Astrophysics Data System (ADS)

    Roux, Bernard; Alekseenko, Elena; Chen, Paul Gang; Kharif, Christian; Kotarba, Richard; Fougere, Dominique

    2014-05-01

    The results from previous studies in lagoons and well mixed estuaries indicate that salt transport is primarily in response to advection associated with freshwater outflow, tidal diffusion, and to shear effects arising from spatial correlations of vertical and especially transverse deviations in salinity and current speed (Smith, 1994). Therefore, the inflow of fresh and salt water into coastal lagoons is an important factor influencing the structure and function of lagoonal ecosystems worldwide (Lirman et al., 2007). The predominance of marine or freshwater inflow leads to the different ecosystems. Among several lagoons located along the Mediterranean shore of France, the Berre lagoon has been under intense anthropogenic pressure for several decades (Delpy et al., 2012). Moreover, the salinity level of the Berre lagoon was varying dramatically from the 19th century up to now. In this work, a special attention is focused on the salinity variation in the Berre lagoon due to the three dominant abiotic forcing mechanisms, i.e., incoming sea tide, runoff from a hydropower and a strong wind. Four different model scenarios were considered in order to examine the impact of each forcing mechanism or combined effects, i.e. : (a) tide only, (b) runoff only, (c) combined tide and runoff, and (d) an N-NW wind, tide and runoff together. Numerical modeling and interpretation of numerical results are based on three-dimensional hydrodynamic model MARS3D. It is found that the strongest negative impact is related to the huge hydropower runoffs, inducing the desalinization of the surface and subsurface waters not only in the centre of the lagoon, but also in the entire water column in the coastal seagrass recolonization zones. In the absence of wind, the huge inputs of freshwater from the hydropower lead to a haline stratification and thus, to anoxic conditions, making most of the lagoon unproductive. On the contrary, strong winds play a positive role on the salinity level of the

  8. Effects of water addition on soil arthropods and soil characteristics in a precipitation-limited environment

    NASA Astrophysics Data System (ADS)

    Chikoski, Jennifer M.; Ferguson, Steven H.; Meyer, Lense

    2006-09-01

    We investigated the effect of water addition and season on soil arthropod abundance and soil characteristics (%C, %N, C:N, moisture, pH). The experimental design consisted of 24 groups of five boxes distributed within a small aspen stand in Saskatchewan, Canada. The boxes depressed the soil to create a habitat with suitable microclimate for soil arthropods, and by overturning boxes we counted soil arthropods during weekly surveys from April to September 1999. Soil samples were collected at two-month intervals and water was added once per week to half of the plots. Of the eleven recognizable taxonomic units identified, only mites (Acari) and springtails (Collembola) responded to water addition by increasing abundance, whereas ants decreased in abundance with water addition. During summer, springtail numbers increased with water addition, whereas pH was a stronger determinant of mite abundance. In autumn, springtails were positively correlated with water and negatively correlated with mites, whereas mite abundance was negatively correlated with increasing C:N ratio, positively correlated to water addition, and negatively correlated with springtail abundance. Although both mite and springtail numbers decreased in autumn with a decrease in soil moisture, mites became more abundant than springtails suggesting a predator-prey (mite-springtail) relationship. Water had a significant effect on both springtails and mites in summer and autumn supporting the assertion that prairie soil communities are water limited.

  9. Biochar mitigates negative effects of salt additions on two herbaceous plant species.

    PubMed

    Thomas, Sean C; Frye, Susan; Gale, Nigel; Garmon, Matthew; Launchbury, Rebecca; Machado, Natasha; Melamed, Sarah; Murray, Jessica; Petroff, Alexandre; Winsborough, Carolyn

    2013-11-15

    Addition of pyrolyzed biomass ("biochar") to soils has commonly been shown to increase crop yields and alleviate plant stresses associated with drought and exposure to toxic materials. Here we investigate the ability of biochar (at two dosages: 5 and 50 t ha(-1)) to mitigate salt-induced stress, simulating road salt additions in a factorial glasshouse experiment involving the broadleaved herbaceous plants Abutilon theophrasti and Prunella vulgaris. Salt additions of 30 g m(-2) NaCl to unamended soils resulted in high mortality rates for both species. Biochar (Fagus grandifolia sawdust pyrolyzed at 378 °C), when applied at 50 t ha(-1) as a top dressing, completely alleviated salt-induced mortality in A. theophrasti and prolonged survival of P. vulgaris. Surviving A. theophrasti plants that received both 50 t ha(-1) biochar and salt addition treatments showed growth rates and physiological performance similar to plants without salt addition. Biochar treatments alone also substantially increased biomass of P. vulgaris, with a ∼50% increase relative to untreated controls at both biochar dosages. Biochar did not significantly affect photosynthetic carbon gain (Amax), water use efficiency, or chlorophyll fluorescence (Fv/Fm) in either species. Our results indicate that biochar can ameliorate salt stress effects on plants through salt sorption, suggesting novel applications of biochar to mitigate effects of salinization in agricultural, urban, and contaminated soils.

  10. Towards understanding the effects of additives on the vermicomposting of sewage sludge.

    PubMed

    Xing, Meiyan; Lv, Baoyi; Zhao, Chunhui; Yang, Jian

    2015-03-01

    This work evaluated the effects of additives on the chemical properties of the final products (vermicompost) from vermicomposting of sewage sludge and the adaptable characteristics of Eisenia fetida during the process. An experimental design with different ratios of sewage sludge and the additives (cattle dung or pig manure) was conducted. The results showed that the vermicomposting reduced total organic carbon and the quotient of total organic carbon to total nitrogen (C/N ratio) of the initial mixtures and enhanced the stability and agronomical value of the final products. Notably, principal component analysis indicated that the additives had significant effects on the characteristics of the vermicomposts. Moreover, the vermibeds containing cattle dung displayed a better earthworm growth and reproduction than those with pig manure. Additionally, redundancy analysis demonstrated that electrical conductivity (EC), pH, and C/N ratio played crucial roles on earthworm growth and reproduction. In all, the additives with high C/N ratio, pH buffering capacity, and low EC are recommended to be used for vermicomposting of sewage sludge.

  11. Effects of aluminum additions to gas atomized reaction synthesis produced oxide dispersion strengthened alloys

    NASA Astrophysics Data System (ADS)

    Spicher, Alexander Lee

    The production of an aluminum containing ferritic oxide dispersion strengthened (ODS) alloy was investigated. The production method used in this study was gas atomization reaction synthesis (GARS). GARS was chosen over the previously commercial method of mechanical alloying (MA) process due to complications from this process. The alloy compositions was determined from three main components; corrosion resistance, dispersoid formation, and additional elements. A combination of Cr and Al were necessary in order to create a protective oxide in the steam atmosphere that the boiler tubing in the next generation of coal-fired power plants would be exposed to. Hf and Y were chosen as dispersoid forming elements due to their increased thermal stability and potential to avoid decreased strength caused by additions of Al to traditional ODS materials. W was used as an additive due to benefits as a strengthener as well as its benefits for creep rupture time. The final composition chosen for the alloy was Fe-16Cr-12Al-0.9W-0.25Hf-0.2Y at%. The aforementioned alloy, GA-1-198, was created through gas atomization with atomization gas of Ar-300ppm O2. The actual composition created was found to be Fe-15Cr-12.3Al-0.9W-0.24Hf-0.19Y at%. An additional alloy that was nominally the same without the inclusion of aluminum was created as a comparison for the effects on mechanical and corrosion properties. The actual composition of the comparison alloy, GA-1-204, was Fe-16Cr-0Al-0.9W-0.25Hf-0.24Y at%. An investigation on the processing parameters for these alloys was conducted on the GA-1-198 alloy. In order to predict the necessary amount of time for heat treatment, a diffusion study was used to find the diffusion rate of oxygen in cast alloys with similar composition. The diffusion rate was found to be similar to that of other GARS compositions that have been created without the inclusion of aluminum. The effect of heat treatment time was investigated with temperatures of 950°C, 1000

  12. Effect of the Addition of Schisandra chinensis Powder on the Physico-chemical Characteristics of Sausage

    PubMed Central

    Jin, S. K.; Park, J. H.

    2013-01-01

    The individual and interactive effects of Schisandra chinensis powder (SCP) and sodium nitrite additions on color, pH, water holding capacity, residual nitrite, 2-thiobarbituric acid reactive substances (TBARS), volatile basic nitrogen, texture properties, fatty acids, amino acids and sensory evaluation of cooked pork sausages were investigated after 20 d of storage at 4°C. The powders (0, 0.5 and 1.0%) were added to sausages either alone or in combination with nitrite (0 and 100 ppm). SCP added-sausages showed lower L* (lightness) and W (whiteness) values, and higher b* (yellowness) values than sausage containing no nitrite, and exhibited the highest a* values at a 0.5% addition (p<0.05). Residual nitrite and TBARS values were found to be significantly reduced as the addition levels of SCP increased (p<0.05). As the addition of SCP increased, the sausage showed gradually decreased brittleness, cohesiveness, springiness, gumminess and chewiness, while adhesiveness increased. Polyunsaturated fatty acid, n-6 and n-6/n-3 fatty acid ratio concentrations were significantly higher in sausages containing SCP (p<0.05). The addition of SCP to sausage significantly (p<0.05) increased the ammonia content (by 0.5% SCP) and aromatic amino acid concentrations (by 1.0% SCP) (p<0.05). Inclusion of SCP in sausage meat resulted in a significant deterioration in quality characteristics of flavor, springiness, juiciness and overall acceptability (p<0.05). As expected, the observed changes in a*, W, pH, shear force, texture property, TBARS, fatty acid, amino acid and sensory score of sausages, depended on the rate of addition of nitrite (p<0.05). These results suggest that SCP addition is not an effective way of improving the sensory evaluation of sausages, but may beneficially affect TBARS, nitrite scavenging activity, fatty acid and amino acid content in pork sausages. PMID:25049766

  13. Effect of ensiling and silage additives on fatty acid composition of ryegrass and corn experimental silages.

    PubMed

    Alves, S P; Cabrita, A R J; Jerónimo, E; Bessa, R J B; Fonseca, A J M

    2011-08-01

    Two experiments were conducted using laboratory mini-silos to study the effect of ensiling and silage additives on fatty acid (FA) composition, including minor or unusual FA, of ryegrass and corn silages. Ryegrass was ensiled for 12 wk with no additives, with the addition of a bacterial inoculant or formic acid. Corn was ensiled for 9 wk without additives, with the addition of a bacterial inoculant or calcium formate. Ensiling affected both total FA content and FA composition of ryegrass silages. Total FA concentration increased (P < 0.001) during ryegrass ensiling. The proportions (g/100 g of total FA) of the major unsaturated FA, 18:3n-3 and 18:2n-6, were not affected (P > 0.05) by ensiling. However, their concentration (mg/g of DM) in silages was greater (P=0.017 and P=0.001, respectively) than in fresh ryegrass. Two 18:2 FA (trans-11,cis-15 and cis-9,cis-15) that were not originally present in the fresh ryegrass were detected in silages. Silage additives affected the FA composition of ryegrass silages, mostly by increasing the proportions of SFA, but not on total FA concentration. Ensiling did not affect (P=0.83) total FA content of corn silages; however, FA composition was affected, mostly by decreasing the proportions of 18:2n-6 and 18:3n-3. Silage additives had no effect on corn silage FA composition. Exposing corn silages to air resulted in no oxidation of FA or reduction in total FA content or composition.

  14. The Effect of Silicon and Aluminum Additions on the Oxidation Resistance of Lean Chromium Stainless Steels

    SciTech Connect

    Dunning, J.S.; Alman, D.E.; Rawers, J.C.

    2001-09-01

    The effect of Si and Al additions on the oxidation of lean chromium austenitic stainless steels has been studied. A baseline composition of Fe-16Cr-16Ni-2Mn-1Mo was selected to allow combined Si and Al additions of up to 5 wt. pct. in a fully austenitic alloy. The baseline composition was selected using a net Cr equivalent equation to predict the onset of G-ferrite formation in austenite. Cyclic oxidation tests in air for 1000 hours were carried out on alloys with Si only or combined Si and Al additions in the temperature range 700 C to 800 C. Oxidation resistance of alloys with Si only additions were outstanding, particularly at 800 C. It was evident that different rate controlling mechanisms for oxidation were operative at 700 C and 800 C in the Si alloys. In addition, Si alloys pre-oxidized at 800 C, showed a zero weight gain in subsequent testing for 1000 hours at 700 C. The rate controlling mechanism in alloys with combined Si and Al addition for oxidation at 800 C was also different than alloys with Si only. SEM and ESCA analysis of the oxide films and base material at the oxide/base metal interface were conducted to study potential rate controlling mechanisms.

  15. Effect of lubricant extreme pressure additives on rolling element fatigue life

    NASA Technical Reports Server (NTRS)

    Parker, R. J.; Zaretsky, E. V.

    1973-01-01

    The effects of surface active additives on rolling-element fatigue life were investigated with the five-ball fatigue tester at conditions where classical subsurface initiated rolling-element fatigue is the sole mode of failure. Test balls of AISI 52100, AISI M-50, and AISI 1018 were run with an acid-treated white oil containing either 2.5 percent sulfurized terpene, 1 percent didodecyl phosphite, or 5 percent chlorinated wax. In general, it was found that the influence of surface active additives was detrimental to rolling-element fatigue life. The chlorinated-wax additive significantly reduced fatigue life by a factor of 7. The base oil with the 2.5 percent sulfurized-terpene additive can reduce fatigue life by as much as 50 percent. No statistical change in fatigue life occurred with the base oil having the 1 percent didodecyl-phosphite additive. The additives used with the base oil did not change the ranking of the bearing steels where rolling-element fatigue life was of subsurface origin.

  16. Additive effects of neurofeedback on the treatment of ADHD: A randomized controlled study.

    PubMed

    Lee, Eun-Jeong; Jung, Chul-Ho

    2017-02-01

    Neurofeedback (NF) has been identified as a "possibly efficacious" treatment in current evidence-based reviews; therefore, more research is needed to determine its effects. The current study examined the potential additive effect of NF for children diagnosed with ADHD beginning a medication trial first. Thirty-six children (6-12 years) with a DSM-IV-TR diagnosis of ADHD were randomly assigned to an NF with medication (NF condition) or a medication only condition. Children in the NF group attended 20 twice-weekly sessions. Outcome measures included individual cognitive performance scores (ADS, K-WISC-III), ADHD rating scores completed by their parents (ARS, CRS) and brainwave indices of left and right hemispheres before and after NF treatment. Significant additive treatment effect in any of the symptom variables was found and a reduction of theta waves in both the right and left hemispheres was recorded in NF condition participants. However our randomized controlled study could not demonstrate superior effects of combined NF on intelligent functioning compared to the medication treatment only. This study suggested any possible evidence of positive and additive treatment effects of NF on brainwaves and ADHD symptomatology.

  17. Effects of water and nitrogen addition on species turnover in temperate grasslands in northern China.

    PubMed

    Xu, Zhuwen; Wan, Shiqiang; Ren, Haiyan; Han, Xingguo; Li, Mai-He; Cheng, Weixin; Jiang, Yong

    2012-01-01

    Global nitrogen (N) deposition and climate change have been identified as two of the most important causes of current plant diversity loss. However, temporal patterns of species turnover underlying diversity changes in response to changing precipitation regimes and atmospheric N deposition have received inadequate attention. We carried out a manipulation experiment in a steppe and an old-field in North China from 2005 to 2009, to test the hypothesis that water addition enhances plant species richness through increase in the rate of species gain and decrease in the rate of species loss, while N addition has opposite effects on species changes. Our results showed that water addition increased the rate of species gain in both the steppe and the old field but decreased the rates of species loss and turnover in the old field. In contrast, N addition increased the rates of species loss and turnover in the steppe but decreased the rate of species gain in the old field. The rate of species change was greater in the old field than in the steppe. Water interacted with N to affect species richness and species turnover, indicating that the impacts of N on semi-arid grasslands were largely mediated by water availability. The temporal stability of communities was negatively correlated with rates of species loss and turnover, suggesting that water addition might enhance, but N addition would reduce the compositional stability of grasslands. Experimental results support our initial hypothesis and demonstrate that water and N availabilities differed in the effects on rate of species change in the temperate grasslands, and these effects also depend on grassland types and/or land-use history. Species gain and loss together contribute to the dynamic change of species richness in semi-arid grasslands under future climate change.

  18. Effective Mechanical Properties of Lattice Material Fabricated by Material Extrusion Additive Manufacturing

    SciTech Connect

    Park, Sang-In; Choi, Seung-kyum; Rosen, David W; Duty, Chad E

    2014-01-01

    In this paper, a two-step homogenization method is proposed and implemented for evaluating effective mechanical properties of lattice structured material fabricated by the material extrusion additive manufacturing process. In order to consider the characteristics of the additive manufacturing process in estimation procedures, the levels of scale for homogenization are divided into three stages the levels of layer deposition, structural element, and lattice structure. The method consists of two transformations among stages. In the first step, the transformation between layer deposition and structural element levels is proposed to find the geometrical and material effective properties of structural elements in the lattice structure. In the second step, the method to estimate effective mechanical properties of lattice material is presented, which uses a unit cell and is based on the discretized homogenization method for periodic structure. The method is implemented for cubic lattice structure and compared to experimental results for validation purposes.

  19. Additive Effects of Alcohols, Their Acidic By-Products, and Temperature on the Yeast Pachysolen tannophilus.

    PubMed

    Barbosa, M de F; Lee, H; Collins-Thompson, D L

    1990-02-01

    The effects of alcohols on the growth and fermentation of the yeast Pachysolen tannophilus were investigated at both 30 and 35 degrees C. Addition of alcohols to the culture medium decreased both the growth rate and the final cell yield in a dose-dependent manner, and this decrease was more severe at 35 degrees C. The concentration for 50% growth rate inhibition decreased as the chain length of the alcohol increased. In fermentations using a high initial cell density, production of acids was always observed when the medium was supplemented with alcohols. Supplementation of the culture medium with a short-chain alcohol plus the corresponding acid was shown to exert an additive deleterious effect on fermentation, and this effect increased with temperature. Production of acids was associated with the presence of alcohol dehydrogenase activity in cell extracts.

  20. The effect of diamic acid additives on the dielectric constant of polyimides

    NASA Technical Reports Server (NTRS)

    Stoakley, Diane M.; St. Clair, Anne K.

    1988-01-01

    The effect of six selected diamic acids additives (including 2,2-prime bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride-aniline (An); 4,4-prime-oxydiphthalic anhydride-An, 3,3-prime diaminodiphenyl sulfone-phthalic anhydride (PA); 4,4-prime-oxydianiline-PA; 2,2-bis 4(4-aminophenoxy)phenyl hexafluoropropane-PA; and 2,2-bis 4(3-aminophenoxy)phenyl hexafluoropropane-PA) on the dielectric constants of low-dielectric-constant polyimide resins was evaluated. It was found that the effect of the incorporation of the diamic acids on reducing the dielectric constant of polyimides may be limited as the dielectric constant of the base resin itself becomes very low. The additives were found to lower the resin's values of glass transition temperature, with no effect on thermooxidative stability.

  1. Effect of indium addition in U-Zr metallic fuel on lanthanide migration

    NASA Astrophysics Data System (ADS)

    Kim, Yeon Soo; Wiencek, T.; O'Hare, E.; Fortner, J.; Wright, A.; Cheon, J. S.; Lee, B. O.

    2017-02-01

    Advanced fast reactor concepts to achieve ultra-high burnup (∼50%) require prevention of fuel-cladding chemical interaction (FCCI). Fission product lanthanide accumulation at high burnup is substantial and significantly contributes to FCCI upon migration to the cladding interface. Diffusion barriers are typically used to prevent interaction of the lanthanides with the cladding. A more active method has been proposed which immobilizes the lanthanides through formation of stable compounds with an additive. Theoretical analysis showed that indium, thallium, and antimony are good candidates. Indium was the strongest candidate because of its low reactivity with iron-based cladding alloys. Characterization of the as-fabricated alloys was performed to determine the effectiveness of the indium addition in forming compounds with lanthanides, represented by cerium. Tests to examine how effectively the dopant prevents lanthanide migration under a thermal gradient were also performed. The results showed that indium effectively prevented cerium migration.

  2. Predicting the effects of nanoscale cerium additives in diesel fuel on regional-scale air quality.

    PubMed

    Erdakos, Garnet B; Bhave, Prakash V; Pouliot, George A; Simon, Heather; Mathur, Rohit

    2014-11-04

    Diesel vehicles are a major source of air pollutant emissions. Fuel additives containing nanoparticulate cerium (nCe) are currently being used in some diesel vehicles to improve fuel efficiency. These fuel additives also reduce fine particulate matter (PM2.5) emissions and alter the emissions of carbon monoxide (CO), nitrogen oxides (NOx), and hydrocarbon (HC) species, including several hazardous air pollutants (HAPs). To predict their net effect on regional air quality, we review the emissions literature and develop a multipollutant inventory for a hypothetical scenario in which nCe additives are used in all on-road and nonroad diesel vehicles. We apply the Community Multiscale Air Quality (CMAQ) model to a domain covering the eastern U.S. for a summer and a winter period. Model calculations suggest modest decreases of average PM2.5 concentrations and relatively larger decreases in particulate elemental carbon. The nCe additives also have an effect on 8 h maximum ozone in summer. Variable effects on HAPs are predicted. The total U.S. emissions of fine-particulate cerium are estimated to increase 25-fold and result in elevated levels of airborne cerium (up to 22 ng/m3), which might adversely impact human health and the environment.

  3. Investigation of the effects of short chain processing additives on polymers

    NASA Technical Reports Server (NTRS)

    Singh, J. J.; Stclair, T. L.; Pratt, J. R.

    1986-01-01

    The effects of low level concentrations of several short chain processing additives on the properties of the 4,4'-bis(3,4-dicarboxyphenoxy) diphenylsulfide dianhydride (BDSDA)/4,4'-diaminodiphenyl ether (ODA)/1,3'-diaminobenzene (m-phenylene diamine) (MPA) (422) copolyimide were investigated. It was noted that 5 percent MPD/phthalic anhydride (PA) is more effective than 5 percent ODA/PA and BDSDA/aniline (AN) in strengthening the host material. However, the introduction of 10 percent BDSDA/AN produces disproportionately high effects on free volume and free electron density in the host copolyimide.

  4. The Effect of Gaseous Additives on Dynamic Pressure Output and Ignition Sensitivity of Nanothermites

    NASA Astrophysics Data System (ADS)

    Puszynski, Jan; Doorenbos, Zac; Walters, Ian; Redner, Paul; Kapoor, Deepak; Swiatkiewicz, Jacek

    2011-06-01

    This contribution addresses important combustion characteristics of nanothermite systems. In this research the following nanothermites were investigated: a) Al-Bi2O3, b)Al-Fe2O3 and c)Al-Bi2O3-Fe2O3. The effect of various gasifying additives (such as nitrocellulose (NC) and cellulose acetate butyrate (CAB)) as well as reactant stoichiometry, reactant particle size and shape on processability, ignition delay time and dynamic pressure outputs at different locations in a combustion chamber will be presented. In addition, this contribution will report electrostatic and friction sensitivities of standard and modified nanothermites.

  5. Effects of Ce additions on the age hardening response of Mg–Zn alloys

    SciTech Connect

    Langelier, Brian Esmaeili, Shahrzad

    2015-03-15

    The effects of Ce additions on the precipitation hardening behaviour of Mg–Zn are examined for a series of alloys, with Ce additions at both alloying and microalloying levels. The alloys are artificially aged, and studied using hardness measurement and X-ray diffraction, as well as optical and transmission electron microscopy. It is found that the age-hardening effect is driven by the formation of fine precipitates, the number density of which is related to the Zn content of the alloy. Conversely, the Ce content is found to slightly reduce hardening. When the alloy content of Ce is high, large secondary phase particles containing both Ce and Zn are present, and remain stable during solutionizing. These particles effectively reduce the amount of Zn available as solute for precipitation, and thereby reduce hardening. Combining hardness results with thermodynamic analysis of alloy solute levels also suggests that Ce can have a negative effect on hardening when present as solutes at the onset of ageing. This effect is confirmed by designing a pre-ageing heat treatment to preferentially remove Ce solutes, which is found to restore the hardening capability of an Mg–Zn–Ce alloy to the level of the Ce-free alloy. - Highlights: • The effects of Ce additions on precipitation in Mg–Zn alloys are examined. • Additions of Ce to Mg–Zn slightly reduce the age-hardening response. • Ce-rich secondary phase particles deplete the matrix of Zn solute. • Hardening is also decreased when Ce is present in solution. • Pre-ageing to preferentially precipitate out Ce restores hardening capabilities.

  6. Addition of alarm pheromone components improves the effectiveness of desiccant dusts against Cimex lectularius.

    PubMed

    Benoit, Joshua B; Phillips, Seth A; Croxall, Travis J; Christensen, Brady S; Yoder, Jay A; Denlinger, David L

    2009-05-01

    We demonstrate that the addition of bed bug, Cimex lectularius, alarm pheromone to desiccant formulations greatly enhances their effectiveness during short-term exposure. Two desiccant formulations, diatomaceous earth (DE) and Dri-die (silica gel), were applied at the label rate with and without bed bug alarm pheromone components, (E)-2-hexenal, (E)-2-octenal, and a (E)-2-hexenal:(E)-2-octenal blend. First-instar nymphs and adult females were subjected to 10-min exposures, and water loss rates were used to evaluate the response. Optimal effectiveness was achieved with a pheromone concentration of 0.01 M. With Dri-die alone, the water loss was 21% higher than in untreated controls, and water loss increased nearly two times with (E)-2-hexenal and (E)-2-octenal and three times with the (E)-2-hexenal: (E)-2-octenal blend. This shortened survival of first-instar nymphs from 4 to 1 d, with a similar reduction noted in adult females. DE was effective only if supplemented with pheromone, resulting in a 50% increase in water loss over controls with the (E)-2-hexenal:(E)-2-octenal blend, and a survival decrease from 4 to 2 d in first-instar nymphs. Consistently, the addition of the pheromone blend to desiccant dust was more effective than adding either component by itself or by using Dri-die or DE alone. Based on observations in a small microhabitat, the addition of alarm pheromone components prompted bed bugs to leave their protective harborages and to move through the desiccant, improving the use of desiccants for control. We concluded that short exposure to Dri-die is a more effective treatment against bed bugs than DE and that the effectiveness of the desiccants can be further enhanced by incorporation of alarm pheromone. Presumably, the addition of alarm pheromone elevates excited crawling activity, thereby promoting cuticular changes that increase water loss.

  7. Effects of CH3OH Addition on Plasma Electrolytic Oxidation of AZ31 Magnesium Alloys

    NASA Astrophysics Data System (ADS)

    He, Yongyi; Chen, Li; Yan, Zongcheng; Zhang, Yalei

    2015-09-01

    Plasma electrolytic oxidation (PEO) films on AZ31 magnesium alloys were prepared in alkaline silicate electrolytes (base electrolyte) with the addition of different volume concentrations of CH3OH, which was used to adjust the thickness of the vapor sheath. The compositions, morphologies, and thicknesses of ceramic layers formed with different CH3OH concentrations were determined via X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and scanning electron microscopy (SEM). Corrosion behavior of the oxide films was evaluated in 3.5 wt.% NaCl solution using potentiodynamic polarization tests. PEO coatings mainly comprised Mg, MgO, and Mg2SiO4. The addition of CH3OH in base electrolytes affected the thickness, pores diameter, and Mg2SiO4 content in the films. The films formed in the electrolyte containing 12% CH3OH exhibited the highest thickness. The coatings formed in the electrolyte containing different concentrations of CH3OH exhibited similar corrosion resistance. The energy consumption of PEO markedly decreased upon the addition of CH3OH to the electrolytes. The result is helpful for energy saving in the PEO process. supported by National Natural Science Foundation of China (No. 21376088), the Project of Production, Education and Research, Guangdong Province and Ministry of Education (Nos. 2012B09100063, 2012A090300015), and Guangzhou Science and Technology Plan Projects of China (No. 2014Y2-00042)

  8. Effect of GdL Addition on Physico-chemical Properties of Fermented Sausages during Ripening.

    PubMed

    Yim, Dong-Gyun; Jang, Kyoung-Hwan; Chung, Ku-Young

    2015-01-01

    This study investigated the effects of glucono-δ-lactone (GdL) addition on physicochemical and microbiological characteristics of fermented sausages during ripening and drying. Five batches of sausages were produced under ripening conditions: without GdL and with 0, 0.1, 0.25, 0.5 and 0.75% of GdL addition. Samples from each treatment were taken for physicochemical and microbiological analyses on the 0, 1, 3, 5, 7, 10, 15, 20 and 25th day of ripening. Chemical analysis showed a significant decrease in moisture content of sausages with increasing amounts of GdL added (p<0.05). The moisture contents decreased, whereas the fat, protein and ash contents increased throughout ripening (p<0.05). Increasing levels of GdL caused a decrease in the pH values (p<0.05), which can have an inhibitory effect against microflora. Water holding capacity content of samples decreased with increasing GdL concentration (p<0.05). The shear force values of fermented sausages showed the highest in T4 (p<0.05). During ripening, the shear force values of sausages were increased on the 25th day compared to day 0 (p<0.05). The higher GdL level produced lighter and more yellow sausages. The addition of 0.75% GdL was effective in controlling bacteria counts. Addition of GdL in sausages resulted in the physicochemical and microbiological attributes equal to or better than no addition of GdL without any harmful effect.

  9. Endothelium-dependent vasodilation effects of Panax notoginseng and its main components are mediated by nitric oxide and cyclooxygenase pathways

    PubMed Central

    Wang, Yanyan; Ren, Yu; Xing, Leilei; Dai, Xiangdong; Liu, Sheng; Yu, Bin; Wang, Yi

    2016-01-01

    Panax notoginseng, a traditional Chinese herbal medicine, has been used for the treatment of cardiovascular diseases. The main bioactive components of this species are Panax notoginseng saponins (PNS). The present study aimed to investigate the effects of PNS and five of its main components (ginsenosides Rg1, Re, Rb1 and Rd, and notoginsenoside R1) on rat aorta rings pre-contracted with norepinephrine (NE) and to determine the underlying mechanism of action. Isolated aorta rings (with or without intact endothelium) from adult male Wistar rats were stimulated with NE to induce vasoconstriction, and subsequently treated with different concentrations of PNS and its five main components (Rg1, Re, Rb1, R1 and Rd) separately. This procedure was repeated after pre-incubation with the nitric oxide (NO) synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME), the guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) and the cyclooxygenase (COX) inhibitor indomethacin (INDO), in order to elucidate the mechanism of action of PNS and its components. The results demonstrated that PNS and the components Rg1, Re, Rb1 and R1, but not Rd, induced vessel relaxation in a concentration-dependent manner when the endothelium lining was intact. NO synthase inhibitor L-NAME and guanylate cyclase inhibitor ODQ attenuated the diastolic effects of PNS, Rg1, Re, Rb1 and R1 in aortic rings with intact endothelium. By contrast, INDO, a known COX inhibitor weakened the vasodilation effects of PNS, Re and Rb1 but demonstrated no effect on Rg1 and R1. In conclusion, PNS and two of its main components (Re and Rb1) exert vasodilating effects through the NO and COX pathways. PMID:28101178

  10. Effects of CYP2C19 polymorphism on the pharmacokinetics of lansoprazole and its main metabolites in healthy Chinese subjects.

    PubMed

    Zhang, Dan; Wang, Xiaolin; Yang, Man; Wang, Guocai; Liu, Huichen

    2011-06-01

    The aim of the study was to determine the pharmacokinetics of lansoprazole and its main metabolites (5'-hydroxy lansoprazole and lansoprazole sulphone) after administration of enteric-coated tablet in healthy Chinese subjects classified by CYP2C19 genotypes, and evaluate the effects of CYP2C19 genotypes on the pharmacokinetics of the three compounds. A single oral dose of 30 mg lansoprazole was administrated to 24 healthy Chinese male volunteers in different CYP2C19 genotype groups. Blood samples were collected from pre-dose up to 14-h post-dose. Plasma concentration of lansoprazole and its main metabolites were quantified by liquid chromatography-tandem mass spectrometry. CYP2C19 polymorphism had significant effects on the pharmacokinetics of lansoprazole and its main metabolites. The differences in the pharmacokinetics between CYP2C19 extensive metabolizers (Ems) (homo-EMs and hete-EMs) and PMs were more significant for lansoprazole sulphone than for 5'-hydroxy lansoprazole. The results indicate that the monitoring of lansoprazole and its main metabolites in plasma at the time-points in the elimination phase for lansoprazole could reflect the activity of CYP2C19. Simultaneously monitored with lansoprazole sulphone, lansoprazole might be a useful probe drug for CYP2C19.

  11. Main Squeeze

    ERIC Educational Resources Information Center

    Lott, Jeffrey

    2010-01-01

    A survey of more than 35,000 alumni magazine readers conducted by CASE and more than 135 member institutions in the United States provides powerful evidence that, among the communications options in the advancement toolbox, magazines are one of the most effective ways to connect with, engage, and motivate alumni and other constituents. The CASE…

  12. Explanation of non-additive effects in mixtures of similar mode of action chemicals.

    PubMed

    Kamo, Masashi; Yokomizo, Hiroyuki

    2015-09-01

    Many models have been developed to predict the combined effect of drugs and chemicals. Most models are classified into two additive models: independent action (IA) and concentration addition (CA). It is generally considered if the modes of action of chemicals are similar then the combined effect obeys CA; however, many empirical studies report nonlinear effects deviating from the predictions by CA. Such deviations are termed synergism and antagonism. Synergism, which leads to a stronger toxicity, requires more careful management, and hence it is important to understand how and which combinations of chemicals lead to synergism. In this paper, three types of chemical reactions are mathematically modeled and the cause of the nonlinear effects among chemicals with similar modes of action was investigated. Our results show that combined effects obey CA only when the modes of action are exactly the same. Contrary to existing knowledge, combined effects are generally nonlinear even if the modes of action of the chemicals are similar. Our results further show that the nonlinear effects vanish out when the chemical concentrations are low, suggesting that the current management procedure of assuming CA is rarely inappropriate because environmental concentrations of chemicals are generally low.

  13. [Effects of biochar addition into soils in semiarid land on water infiltration under the condition of the same bulk density].

    PubMed

    Qi, Rui-Peng; Zhang, Lei; Yan, Yong-Hao; Wen, Man; Zheng, Ji-Yong

    2014-08-01

    Making clear the effects of biochar addition on soil water infiltration process can provide the scientific basis for the evaluation of the influence of biochar application on soil hydrology in semi-arid region. In this paper, through the soil column simulation method in laboratory, the effects of biochar of three sizes (1-2 mm, 0.25-1 mm and ≤ 0.25 mm) at 4 doses (10, 50, 100 and 150 g x kg(-1)) on the cumulative infiltration, the permeability and the stable infiltration rate of two different soils (anthrosol and aeolian sandy soil) were studied. The results showed that the infiltration capacity of the anthrosol was obviously increased compared to the control, however, the one in the aeolian sandy soil was decreased due to the biochar addition. At 100 minutes after infiltration starting, the averaged cumulative infiltration was increased by 25.1% in the anthrosol with comparison to the control. Contrarily, the averaged cumulative infiltration was decreased by 11.1% in the aeolian sandy soil at 15 minutes after infiltration starting. When the dose was the same, biochar with different particle sizes improved the infiltration for the anthrosol, but for the different dose treatments, the particle size of biochar which showed the greatest improvement was different. As for the aeolian sandy soil, the infiltration increased at the dose of 10 g x kg(-1) after the addition of biochar with different particle sizes, while decreased at the higher dose of 50, 100 and 150 g x kg(-1). The cumulative infiltration of the aeolian sandy soil was decreased with the increase in addition amount of biochar with the same particle size, while it was not so for the anthrosol. The determination coefficient fitted by the Philip infiltration model ranged from 0.965 to 0.999, suggesting this model was suitable for the simulation of soil water infiltration process after biochar application. Statistical analysis of main effects showed that the biochar particle size, the biochar addition amount

  14. Effect of inorganic additives on solutions of nonionic surfactants V: Emulsion stability.

    PubMed

    Schott, H; Royce, A E

    1983-12-01

    Electrolytes often break emulsions to which they were added as active ingredients, adjuvants, or impurities. The stability of oil-in-water emulsions containing octoxynol 9 NF as the emulsifier and various added electrolytes was investigated by measuring droplet size, turbidity, and oil separation on storage at various temperatures and in a centrifugal field at 25 degrees. Electrolytes were added to hexadecane emulsions after emulsification (direct addition); alternatively, hexadecane was emulsified in octoxynol 9-electrolyte mixtures (reverse addition). Xylene emulsions were prepared by direct addition only. Hexadecane emulsions containing 0.10% octoxynol 9 were considerably more stable than xylene emulsions containing 0.60% because the surfactant is practically insoluble in hexadecane, but miscible in all proportions with xylene. An emulsifier soluble in the disperse phase as well as the continuous phase evidently forms less stable interfacial films. The electrolytes investigated were sulfuric and hydrochloric acids, magnesium nitrate, and aluminum nitrate, which salt octoxynol 9 in by complexation between its ether groups and their cations; sodium thiocyanate, which salts the surfactant in by destructuring water; and sodium chloride and sodium sulfate, which salt octoxynol 9 out. The addition of these electrolytes at concentrations up to 2 or 3 m to hexadecane emulsions produced fast and extensive creaming, little or no flocculation, no coalescence, and only minor changes in droplet size or turbidity on storage at room temperature. The extent of coalescence during centrifugation was actually reduced by the additives. Such stability is unusual. Droplet size and turbidity depended mainly on octoxynol 9 concentration. The greatest decrease in the former and increase in the latter occurred when the concentration was increased from 0.10 to approximately 0.4%. All emulsions became slightly coarser on storage at 25 degrees. Stability at 50 degrees was impaired by

  15. Effect of kaolin addition on the performance of controlled low-strength material using industrial waste incineration bottom ash.

    PubMed

    Naganathan, Sivakumar; Razak, Hashim Abdul; Hamid, Siti Nadzriah Abdul

    2010-09-01

    Incineration of industrial waste produces large quantities of bottom ash which are normally sent to secured landfill, but is not a sustainable solution. Use of bottom ash in engineering applications will contribute to sustainability and generate revenue. One way of using the industrial waste incineration bottom ash is in controlled low-strength material (CLSM). Use of bottom ash in CLSM has problems related to bleeding and excessive strength development and so an additive has to be used to control bleeding and strength development. The main objective of this research is to study the effect of kaolin addition on the performance of CLSM made using industrial waste incineration bottom ash. CLSM mixes were made with bottom ash, cement, and refined kaolin. Various tests were performed on the CLSM in fresh and hardened states including compressive strength, water absorption, California bearing ratio (CBR) and the tests for concentration of leachable substances on the bleed and leachate. The compressive strength of CLSM tested ranged from 0.11 to 9.86 MPa. CBR values ranged from 6 to 46, and water absorption values from 12 to 36%. It was shown that the addition of kaolin delayed the initial setting time of CLSM mixtures, reduced bleeding, lowered the compressive strength, and increased the values of water absorption, sorption, and initial surface absorption. The CLSM tested did not have corrosivity. It was shown that the hardened CLSM was non hazardous, and the addition of kaolin increased the concentration of heavy metals and salts in the bleed and leachate.

  16. Effect on the operation properties of DMBR with the addition of GAC

    NASA Astrophysics Data System (ADS)

    Lin, Jizhi; Zhang, Qian; Hong, Junming

    2017-01-01

    The membrane bioreactor and dynamic membrane bioreactor were used to examine the effect of granular activated carbon (GAC) on the treatment of synthetic wastewater. After the addition of different volume fractions GAC in the DMBR, the operation parameters, effluent COD, NH4 +-N, NO3 --N, TN concentrations and sludge viscosity of the bioreactor was investigated. The results showed that the addition of GAC could relieve the membrane fouling and improve the removal efficiencies of pollutants in the DMBR. The effluent concentrations of pollutants were linear correlation with the addition of volume fractions of GAC in the bioreactor. The value of R2 of each modulation was almost more than 0.9. The sludge viscosity was almost not affected by the volume fractions of GAC in the bioreactor. The best volume fractions of GAC were 20% in the DMBR.

  17. The effects of beryllium additions on the oxidation of nickel aluminide and titanium aluminide based intermetallics

    SciTech Connect

    Hanrahan, R.J. Jr.; Chen, K.C.; Brady, M.P.

    1998-12-31

    The effects of Be additions on the oxidation behavior of {beta}-NiAl in moist air at 1,000 C and borderline alumina-forming {gamma} (TiAl) + Laves Ti-Al-Cr based alloys at 800 C and 1,000 C in dry and moist air were investigated. The addition of Be to {beta}-NiAl suppressed the formation of transient alumina, and resulted in the formation of a protective BeAl{sub 2}O{sub 4} spinel phase. In dry air, the addition of Be to the Ti-Al-Cr alloys also resulted in the formation of a protective BeAl{sub 2}O{sub 4} spinel phase. In moist air, only Ti-Al-Cr-Be alloys with a high Cr content (10 to 15 a/o) formed the protective BeAl{sub 2}O{sub 4} scale.

  18. The effects of beryllium additions on the oxidation of nickel aluminide and titanium aluminide based intermetallics

    SciTech Connect

    Hanrahan, R.J. Jr.; Chen, K.C.; Brady, M.P.

    1998-11-01

    The effects of Be additions on the oxidation behavior of {beta}-NiAl in moist air at 1,000 C as well as on the borderline alumina-forming {gamma} + Laves Ti-Al-Cr based alloys at 800 C and 1,000 C in dry and moist air were investigated. The addition of Be to {beta}-NiAl suppressed the formation of transient alumina and resulted in the formation of a protective BeAl{sub 2}O{sub 4} spinel phase. In dry air, the addition of Be to the Ti-Al-Cr alloys also resulted in the formation of a protective BeAl{sub 2}O{sub 4} spinel phase. In moist air, only Ti-Al-Cr-Be alloys with a high Cr content (10 to 15 a/o) formed the protective BeAl{sub 2}O{sub 4} scale.

  19. Effect of Nitrogen Additives on Flame Retardant Action of Tributyl Phosphate: Phosphorus – Nitrogen Synergism

    SciTech Connect

    Gaan, Sabyasachi; Sun, Gang; Hutches, Katherine; Engelhard, Mark H.

    2008-01-01

    The effect of nitrogen additives like urea, guanidine carbonate and melamine formaldehyde on the flame retardant efficacy of tributyl phosphate (TBP) has been investigated. From the LOI tests on treated cotton it is clear that the nitrogen additives have synergistic action. Estimation of activation energy of decomposition of treated cotton indicated that nitrogen additives enhance the thermal stability during the burning process. SEM pictures of chars formed after LOI test showed the formation of protective polymeric coating on the surface. The surface of chars formed were evaluated using FTIR-ATR and XPS analysis which showed that the coating was composed of Phosphorus-Nitrogen-Oxygen containing species. Formation of this coating during the burning process could lead to the synergistic interaction of phosphorus and nitrogen. Based on the experimental data we have further proposed several reaction mechanisms which could contribute to synergistic action and formation of protective coating on the surface of char.

  20. Effect of hot pressing additives on the leachability of hot pressed sodium hydrous titanium oxide

    SciTech Connect

    Valentine, T.M.; Sambell, R.A.J.

    1980-01-01

    Sodium hydrous titanium oxide is an ion exchange resin which can be used for immobilizing medium level waste (MLW) liquors. When hot pressed, it undergoes conversion to a ceramic. Three low melting point materials (borax, bismuth trioxide, and a mixture of PbO/CuO) were added to the (Na)HTiO and the effect that each of these had on aiding densification was assessed. Hot pressing temperature, applied pressure, and percentage addition of hot pressing aid were varied. Percentage open porosity, flexural strength, and leachability were measured. There was a linear relationship between the percentage open porosity and the logarithm of the leach rate for a constant percentage addition of each additive.

  1. Effect of additives on mechanical properties of macroporous silicon carbide ceramics

    NASA Astrophysics Data System (ADS)

    Eom, Jung-Hye; Kim, Young-Wook

    2010-06-01

    Macroporous SiC ceramics were fabricated by carbothermal reduction of polysiloxane-derived SiOC containing hollow microspheres, followed by sintering and subsequent annealing. The effects of the additive composition and the annealing temperature on the porosity, microstructure, and mechanical strength of the resulting porous ceramics were investigated. Varying the additive composition was found to result in different porosities, microstructures, and mechanical properties. When the samples were sintered at 1750 °C and then annealed at 1900 °C for 4 h, the SiC prepared with 3% Al2O3 and 2% Y2O3 showed the highest strength (a flexural strength of 55 MPa and a compressive strength of 289 MPa, at a porosity of 45 %). The present results suggest that judicious selection of the sintering additive composition is very important for improving the mechanical properties of macroporous SiC ceramics.

  2. Vector Addition: Effect of the Context and Position of the Vectors

    NASA Astrophysics Data System (ADS)

    Barniol, Pablo; Zavala, Genaro

    2010-10-01

    In this article we investigate the effect of: 1) the context, and 2) the position of the vectors, on 2D vector addition tasks. We administered a test to 512 students completing introductory physics courses at a private Mexican university. In the first part, we analyze students' responses in three isomorphic problems: displacements, forces, and no physical context. Students were asked to draw two vectors and the vector sum. We analyzed students' procedures detecting the difficulties when drawing the vector addition and proved that the context matters, not only compared to the context-free case but also between the contexts. In the second part, we analyze students' responses with three different arrangements of the sum of two vectors: tail-to-tail, head-to-tail and separated vectors. We compared the frequencies of the errors in the three different positions to deduce students' conceptions in the addition of vectors.

  3. Effect of argon addition on plasma parameters and dust charging in hydrogen plasma

    SciTech Connect

    Kakati, B. Kausik, S. S.; Saikia, B. K.; Bandyopadhyay, M.; Saxena, Y. C.

    2014-10-28

    Experimental results on effect of adding argon gas to hydrogen plasma in a multi-cusp dusty plasma device are reported. Addition of argon modifies plasma density, electron temperature, degree of hydrogen dissociation, dust current as well as dust charge. From the dust charging profile, it is observed that the dust current and dust charge decrease significantly up to 40% addition of argon flow rate in hydrogen plasma. But beyond 40% of argon flow rate, the changes in dust current and dust charge are insignificant. Results show that the addition of argon to hydrogen plasma in a dusty plasma device can be used as a tool to control the dust charging in a low pressure dusty plasma.

  4. Effects of chemical additives on hydrocarbon disappearance and biodegradation in freshwater marsh microcosms.

    PubMed

    Nyman, J A; Klerks, P L; Bhattacharyya, S

    2007-09-01

    We determined how a cleaner and a dispersant affected hydrocarbon biodegradation in wetland soils dominated by the plant Panicum hemitomon, which occurs throughout North and South America. Microcosms received no hydrocarbons, South Louisiana crude, or diesel; and no additive, a dispersant, or a cleaner. We determined the concentration of four total petroleum hydrocarbon (TPH) measures and 43 target hydrocarbons in water and sediment fractions 1, 7, 31, and 186 days later. Disappearance was distinguished from biodegradation via hopane-normalization. After 186 days, TPH disappearance ranged from 24% to 97%. There was poor correlation among the four TPH measures, which indicated that each quantified a different suite of hydrocarbons. Hydrocarbon disappearance and biodegradation were unaltered by these additives under worse-case scenarios. Any use of these additives must generate benefits that outweigh the lack of effect on biodegradation demonstrated in this report, and the increase in toxicity that we reported earlier.

  5. Effects of Nitrogen and Phosphorus Additions on Carbon Cycling of Tropical Mountain Rainforests in Hainan, China

    NASA Astrophysics Data System (ADS)

    Lai, J.

    2015-12-01

    Nitrogen (N) and Phosphorus (P) deposition is projected to increase significantly in tropical regions in the coming decades, which has changed and will change the structure and function of ecosystems, and affects on ecosystem Carbon (C) cycle. As an important part in global C cycle, how the C cycle of tropical rainforests will be influenced by the N and P deposition should be focused on. This study simulated N and P deposition in a primary and secondary forest of tropical mountain rainforest in Jianfengling, Hainan, China, during five-year field experiment to evaluate the effects of N and P deposition on C cycling processes and relate characteristics. Six levels of N and P treatments were treated: Control, Low-N, Medium-N, High-N, P and N+P. The relative growth rates (RGR) of tree layer in treatment plots were different from that in control plots after years of N and P addition. Simulated N and P deposition also increased ANPP in primary forest. N and P addition changed the growth of trees by altering soil nutrient and microbial activities. N and P addition increased soil organic carbon (SOC) and total N (TN) content, and significantly increased soil total P (TP) content, not changing soil pH. During the whole process of N and P addition, as net nitrification rate and net N mineralization rate were promoted by N and P addition, and effective N content (nitrate) of soil increased in the plot treated with N treatments compared to the control treatment. The microbial P content was increased by N and P addition, and microbial N was not changed. The increasing N deposition may enhance soil nutrient and stimulate growth of trees, which will lead to an increase of the C sequestration.

  6. Coexposure to phytoestrogens and bisphenol a mimics estrogenic effects in an additive manner.

    PubMed

    Katchy, Anne; Pinto, Caroline; Jonsson, Philip; Nguyen-Vu, Trang; Pandelova, Marchela; Riu, Anne; Schramm, Karl-Werner; Samarov, Daniel; Gustafsson, Jan-Åke; Bondesson, Maria; Williams, Cecilia

    2014-03-01

    Endocrine-disrupting chemicals (EDC) are abundant in our environment. A number of EDCs, including bisphenol A (BPA) can bind to the estrogen receptors (ER), ERα and ERβ, and may contribute to estrogen-linked diseases such as breast cancer. Early exposure is of particular concern; many EDCs cross the placenta and infants have measurable levels of, eg, BPA. In addition, infants are frequently fed soy-based formula (SF) that contains phytoestrogens. Effects of combined exposure to xeno- and phytoestrogens are poorly studied. Here, we extensively compared to what extent BPA, genistein, and an extract of infant SF mimic estrogen-induced gene transcription and cell proliferation. We investigated ligand-specific effects on ER activation in HeLa-ERα and ERβ reporter cells; on proliferation, genome-wide gene regulation and non-ER-mediated effects in MCF7 breast cancer cells; and how coexposure influenced these effects. The biological relevance was explored using enrichment analyses of differentially regulated genes and clustering with clinical breast cancer profiles. We demonstrate that coexposure to BPA and genistein, or SF, results in increased functional and transcriptional estrogenic effects. Using statistical modeling, we determine that BPA and phytoestrogens act in an additive manner. The proliferative and transcriptional effects of the tested compounds mimic those of 17β-estradiol, and are abolished by cotreatment with an ER antagonist. Gene expression profiles induced by each compound clustered with poor prognosis breast cancer, indicating that exposure may adversely affect breast cancer prognosis. This study accentuates that coexposure to BPA and soy-based phytoestrogens results in additive estrogenic effects, and may contribute to estrogen-linked diseases, including breast cancer.

  7. Hydrothermal treatment of incineration fly ash for PCDD/Fs decomposition: the effect of iron addition.

    PubMed

    Chen, De-Zhen; Hu, Yu-Yan; Zhang, Peng-Fei

    2012-12-01

    The catalytic effect of Fe addition on the decomposition of polychlorinated dibenzo-dioxins and polychlorinated dibenzofurans (PCDD/Fs) contained in municipal solid waste incineration (MSWI) fly ash during the hydrothermal process was investigated. Influencing factors, such as Fe addition mode, reaction time and cooling procedure after reaction, were tested to evaluate their effects. Experimental results indicated that Fe addition in the form of a mixture of ferrous sulphate and ferric sulphate enhanced decomposition of PCDD/Fs contained in the MSWI fly ash, particularly for the decomposition of 2,3,7,8-tetrachlorodibenzo-dioxin and 2,3,7,8-tetrachlorodibenzo-furan under the reaction temperature of 563 K. The decomposition rate of PCDD/Fs reached 90.33% by international toxicity equivalent (I-TEQ) when Fe was added as a mixture of ferrous and ferric sulphates by 5% (wt/wt) with the Fe (III)/Fe (II) ratio being 2; without Fe addition, the decomposition rate of PCDD/Fs was only 46.17% by I-TEQ in the same process. Fe addition in the form of ferrous sulphate alone also showed an enhancing effect on PCDD/Fs decomposition, but the associated decomposition rates were relatively lower, suggesting iron oxides formed from the mixture of ferric and ferrous sulphates are more favourable catalysts. At the same time, the cooling procedure after the hydrothermal reaction became more flexible if Fe was added in the form of a mixture of ferric and ferrous sulphates. Although a longer reaction time was helpful to increase decomposition rates of PCDD/Fs, 1 h was proved to be a reasonable time under this condition.

  8. Effect of Cephalaria syriaca addition on rheological properties of composite flour

    NASA Astrophysics Data System (ADS)

    Karaoðlu, M. M.

    2012-10-01

    The study was carried out to investigate the effect of whole and defatted Cephalaria syriaca flour on the rheological properties of composite flours that used in bran bread production. Cephalaria syriaca products were used to replace 0.25, 0.75, 1.25, 1.75, and 2.25% of wheat-wheat bran composite flour, and its rheological and fermentative properties were measured by farinograph, extensograph and rheofermentometre. The data showed that the rheological parameters of flours were greatly modified by addition of Cephalaria syriaca. The rheological properties of wheatwheat bran composite flour added with whole and defatted Cephalaria syriaca flour were considerably improved with regard to especially extensograph characteristics such as dough resistance, area (energy), ratio number and rheofermentometer parameters such as Hm, T1, Tx, volume loss and gas retention, as compared to control. However addition of Cephalaria syriaca products adversely affected the farinograph characteristics. Generally, these effects of both whole and defatted Cephalaria syriaca flour increased, as the addition level increased. Maximum Tx, gas retention and area (energy) of dough were obtained from wheat-wheat bran composite flour added with 1.75% whole Cephalaria syriaca flour, while the highest dough stability was at addition level of 0.25% whole Cephalaria syriaca flour.

  9. Effect of boron addition on the structure and magnetic properties of CoPt nanoparticles

    SciTech Connect

    Khemjeen, Yutthaya; Pinitsoontorn, Supree Chompoosor, Apiwat

    2015-05-07

    The effect of B addition on CoPt nanoparticles was investigated. The CoPt-B nanoparticles were synthesized by means of the polyol process. Transmission electron microscopy has shown that the as-synthesized particles have a spherical morphology with average size about 2–3 nm. The X-ray absorption spectroscopy and the X-ray diffraction technique showed the effect of B concentration on phase transformation. The addition of B at up to 60% promoted the formation of the L1{sub 0} phase when the nanoparticles were subjected to annealing at 600 °C. If the B content is higher than 60%, the phase transition is suppressed. The evidence of B addition on the structure of CoPt nanoparticles was further supported by the magnetic measurements. The results show that the coercivity of the annealed CoPt-B nanoparticles was enhanced by the B additions from 20% to 60%, with the maximum coercivity of 12 000 Oe for the CoPt-40%B sample.

  10. The effect of various additives on Bayer digestion of diasporic bauxite

    SciTech Connect

    Zhang Lunhe; Xu Qili; Wang Xiangli

    1996-10-01

    In this paper, the effect of about ten kinds of additives on Bayer digestion of diasporic bauxite has been investigated. The experiment results has showed that mineral additives such as dolomite, chlorite, medicinal stone, magnesite have a great influence upon the alumina extraction efficiency of diasporite and the scaling property of slurry. Nevertheless, a great quantity of additives must be used, the digestive result of bauxite is not satisfactory (except dolime). So it is difficult to put into practice. In addition, the authors treated lime and red mud or slurry with sodium aluminate liquor to achieve synthesis catalyzators on the definite conditions. Compared to the results when lime was being added, the alumina extraction efficiency of diasporite increased 2--4% when this kind of synthesis catalyzator was being added under otherwise equal conditions, and their molar ratio of digestion liquor (Na{sub 2}O/Al{sub 2}O{sub 3}) decreased 0.03--0.11. The effect is obvious and the technology is simple. The experiment results proved that the synthesis catalyzator have industrial applying value.

  11. Effects of chitosan fiber addition on the properties of polyurethane with thermo-responsive shape memory.

    PubMed

    Kawaguchi, Kyotaro; Iijima, Masahiro; Miyakawa, Hiroshi; Ohta, Mitsuru; Muguruma, Takeshi; Endo, Kazuhiko; Nakazawa, Futoshi; Mizoguchi, Itaru

    2016-03-30

    We investigated the effects of the addition of chitosan fiber (biomass nanofiber made by Sugino (BiNFi-s)) to polyether-based thermoplastic polyurethane (TPU) on material properties. BiNFi-s (2 and 5 wt %)/TPU composite materials were prepared via compression molding, and glass fiber (2 and 5 wt %)/TPU composite materials and plain TPU were also prepared for comparison. The glass transition temperature was analyzed using differential scanning calorimetry, and the crystal structure was investigated using X-ray diffraction. 20-mm-long test specimens with cross-sectional dimensions of 1 mm × 1 mm were cut from sheets of the composite materials, and three-point bending tests were carried out using a universal testing machine to investigate their mechanical properties and shape memory. The addition of BiNFi-s or glass fiber to TPU did not influence the glass transition temperature, although the crystal structure changed from semi-crystalline to amorphous. The elastic modulus increased 40% by the addition of 5 wt % BiNFi-s (2.31 MPa) compared with plain TPU (1.65 MPa), and these composites exhibited shape recovery with clinically relevant changes in temperature. The addition of 5 wt % BiNFi-s into TPU resulted in an improvement in the elastic modulus without any decrease in the shape memory effect. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2016.

  12. Co-digestion of manure and industrial waste--The effects of trace element addition.

    PubMed

    Nordell, Erik; Nilsson, Britt; Nilsson Påledal, Sören; Karisalmi, Kaisa; Moestedt, Jan

    2016-01-01

    Manure is one of the most common substrates for biogas production. Manure from dairy- and swine animals are often considered to stabilize the biogas process by contributing nutrients and trace elements needed for the biogas process. In this study two lab-scale reactors were used to evaluate the effects of trace element addition during co-digestion of manure from swine- and dairy animals with industrial waste. The substrate used contained high background concentrations of both cobalt and nickel, which are considered to be the most important trace elements. In the reactor receiving additional trace elements, the volatile fatty acids (VFA) concentration was 89% lower than in the control reactor. The lower VFA concentration contributed to a more digested digestate, and thus lower methane emissions in the subsequent storage. Also, the biogas production rate increased with 24% and the biogas production yield with 10%, both as a result of the additional trace elements at high organic loading rates. All in all, even though 50% of the feedstock consisted of manure, trace element addition resulted in multiple positive effects and a more reliable process with stable and high yield.

  13. Effects of water and nitrogen addition on ecosystem carbon exchange in a meadow steppe.

    PubMed

    Wang, Yunbo; Jiang, Qi; Yang, Zhiming; Sun, Wei; Wang, Deli

    2015-01-01

    A changing precipitation regime and increasing nitrogen deposition are likely to have profound impacts on arid and semiarid ecosystem C cycling, which is often constrained by the timing and availability of water and nitrogen. However, little is known about the effects of altered precipitation and nitrogen addition on grassland ecosystem C exchange. We conducted a 3-year field experiment to assess the responses of vegetation composition, ecosystem productivity, and ecosystem C exchange to manipulative water and nitrogen addition in a meadow steppe. Nitrogen addition significantly stimulated aboveground biomass and net ecosystem CO2 exchange (NEE), which suggests that nitrogen availability is a primary limiting factor for ecosystem C cycling in the meadow steppe. Water addition had no significant impacts on either ecosystem C exchange or plant biomass, but ecosystem C fluxes showed a strong correlation with early growing season precipitation, rather than whole growing season precipitation, across the 3 experimental years. After we incorporated water addition into the calculation of precipitation regimes, we found that monthly average ecosystem C fluxes correlated more strongly with precipitation frequency than with precipitation amount. These results highlight the importance of precipitation distribution in regulating ecosystem C cycling. Overall, ecosystem C fluxes in the studied ecosystem are highly sensitive to nitrogen deposition, but less sensitive to increased precipitation.

  14. Effect of additives on size and shape of lithium carbonate crystals

    NASA Astrophysics Data System (ADS)

    Taborga, P.; Brito, I.; Graber, T. A.

    2017-02-01

    Generally, properties such internal structure, shape, and size distribution influence the reactivity, fluidity and wettability of the crystals, and may be modified by the use of additives such as polyelectrolytes or surfactants. The aim of this study was to investigate the effect of different additives on the size and morphology of lithium carbonate crystals obtained by reactive crystallization from solutions of LiCl and Na2CO3. The additives used were: polyethylenimine (PEI), polyethylene glycol (PEG), poly (4-styrenesulfonic acid), (P4SA), polyacrylic acid (PAA), sodium dodecyl sulfate (SDS), and sodium dodecyl benzenesulfonate (SDBS). Obtained crystals were observed using scanning electron microscopy, the crystal size distribution was determined by a size image analyzer, and the crystal structure were analyzed by X-ray diffraction. The results showed that the presence of PEI, PEG and P4SA, increased the length of the lithium carbonate particles. The presence of SDS decreases the crystals size. Using SDBS as additive, the crystals had a needle-like shape, Finally PAA allowed the production of Li2CO3 spherulites. Crystal structure of lithium carbonate did not change in the presence of the tested additives.

  15. Effects of two warm-mix additives on aging, rheological and failure properties of asphalt cements

    NASA Astrophysics Data System (ADS)

    Omari, Isaac Obeng

    Sustainable road construction and maintenance could be supported when excellent warm-mix additives are employed in the modification of asphalt. These warm-mix additives provide remedies for today's requirements such as fatigue cracking resistance, durability, thermal cracking resistance, rutting resistance and resistance to moisture damage. Warm-mix additives are based on waxes and surfactants which reduce energy consumption and carbon dioxide emissions significantly during the construction phase of the pavement. In this study, the effects of two warm mix additives, siloxane and oxidised polyethylene wax, on roofing asphalt flux (RAF) and asphalt modified with waste engine oil (655-7) were investigated to evaluate the rheological, aging and failure properties of the asphalt binders. In terms of the properties of these two different asphalts, RAF has proved to be superior quality asphalt whereas 655-7 is poor quality asphalt. The properties of the modified asphalt samples were measured by Superpave(TM) tests such as Dynamic Shear Rheometer (DSR) test and Bending Beam Rheometer (BBR) test as well as modified protocols such as the extended BBR (eBBR) test (LS-308) and the Double- Edge-Notched Tension (DENT) test (LS-299) after laboratory aging. In addition, the Avrami theory was used to gain an insight on the crystallization of asphalt or the waxes within the asphalt binder. This study has however shown that the eBBR and DENT tests are better tools for providing accurate specification tests to curb thermal and fatigue cracking in contemporary asphalt pavements.

  16. Effect of the BSCCO superconducting properties by tiny Y2O3 addition

    NASA Astrophysics Data System (ADS)

    Dong, Yan; Sun, Aimin; Xu, Bin; Zhang, Hongtao; Zhang, Meng

    2016-09-01

    In this paper, the effect of tiny Y2O3 addition in (Bi,Pb)-2223 superconductor prepared by solid state reaction technique was studied. The properties of samples have been investigated via X-ray diffraction (XRD), resistance-temperature (R-T) curve, scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). XRD data indicated that all samples are multiphase and the major phases are high-temperature phases and low-temperature phases. The volume fraction of (Bi,Pb)-2223 is not great change with tiny Y2O3 addition. All samples exhibit superconducting phase with the critical transition temperature and one-step transition, however, the transition width was decreased with the Y2O3 addition up to 0.04 wt.% and sharp increased with the excessive oxide addition. SEM pictures show that the Y2O3 appeared on the flake-type grains surface obviously, but the number and size of the hole between grains are decreased in the 0.04 wt.% addition.

  17. CAN Canopy Addition of Nitrogen Better Illustrate the Effect of Atmospheric Nitrogen Deposition on Forest Ecosystem?

    PubMed

    Zhang, Wei; Shen, Weijun; Zhu, Shidan; Wan, Shiqiang; Luo, Yiqi; Yan, Junhua; Wang, Keya; Liu, Lei; Dai, Huitang; Li, Peixue; Dai, Keyuan; Zhang, Weixin; Liu, Zhanfeng; Wang, Faming; Kuang, Yuanwen; Li, Zhian; Lin, Yongbiao; Rao, Xingquan; Li, Jiong; Zou, Bi; Cai, Xian; Mo, Jiangming; Zhao, Ping; Ye, Qing; Huang, Jianguo; Fu, Shenglei

    2015-06-10

    Increasing atmospheric nitrogen (N) deposition could profoundly impact community structure and ecosystem functions in forests. However, conventional experiments with understory addition of N (UAN) largely neglect canopy-associated biota and processes and therefore may not realistically simulate atmospheric N deposition to generate reliable impacts on forest ecosystems. Here we, for the first time, designed a novel experiment with canopy addition of N (CAN) vs. UAN and reviewed the merits and pitfalls of the two approaches. The following hypotheses will be tested: i) UAN overestimates the N addition effects on understory and soil processes but underestimates those on canopy-associated biota and processes, ii) with low-level N addition, CAN favors canopy tree species and canopy-dwelling biota and promotes the detritus food web, and iii) with high-level N addition, CAN suppresses canopy tree species and other biota and favors rhizosphere food web. As a long-term comprehensive program, this experiment will provide opportunities for multidisciplinary collaborations, including biogeochemistry, microbiology, zoology, and plant science to examine forest ecosystem responses to atmospheric N deposition.

  18. CAN Canopy Addition of Nitrogen Better Illustrate the Effect of Atmospheric Nitrogen Deposition on Forest Ecosystem?

    PubMed Central

    Zhang, Wei; Shen, Weijun; Zhu, Shidan; Wan, Shiqiang; Luo, Yiqi; Yan, Junhua; Wang, Keya; Liu, Lei; Dai, Huitang; Li, Peixue; Dai, Keyuan; Zhang, Weixin; Liu, Zhanfeng; Wang, Faming; Kuang, Yuanwen; Li, Zhian; Lin, Yongbiao; Rao, Xingquan; Li, Jiong; Zou, Bi; Cai, Xian; Mo, Jiangming; Zhao, Ping; Ye, Qing; Huang, Jianguo; Fu, Shenglei

    2015-01-01

    Increasing atmospheric nitrogen (N) deposition could profoundly impact community structure and ecosystem functions in forests. However, conventional experiments with understory addition of N (UAN) largely neglect canopy-associated biota and processes and therefore may not realistically simulate atmospheric N deposition to generate reliable impacts on forest ecosystems. Here we, for the first time, designed a novel experiment with canopy addition of N (CAN) vs. UAN and reviewed the merits and pitfalls of the two approaches. The following hypotheses will be tested: i) UAN overestimates the N addition effects on understory and soil processes but underestimates those on canopy-associated biota and processes, ii) with low-level N addition, CAN favors canopy tree species and canopy-dwelling biota and promotes the detritus food web, and iii) with high-level N addition, CAN suppresses canopy tree species and other biota and favors rhizosphere food web. As a long-term comprehensive program, this experiment will provide opportunities for multidisciplinary collaborations, including biogeochemistry, microbiology, zoology, and plant science to examine forest ecosystem responses to atmospheric N deposition. PMID:26059183

  19. Effects of Water and Nitrogen Addition on Ecosystem Carbon Exchange in a Meadow Steppe

    PubMed Central

    Wang, Yunbo; Jiang, Qi; Yang, Zhiming; Sun, Wei; Wang, Deli

    2015-01-01

    A changing precipitation regime and increasing nitrogen deposition are likely to have profound impacts on arid and semiarid ecosystem C cycling, which is often constrained by the timing and availability of water and nitrogen. However, little is known about the effects of altered precipitation and nitrogen addition on grassland ecosystem C exchange. We conducted a 3-year field experiment to assess the responses of vegetation composition, ecosystem productivity, and ecosystem C exchange to manipulative water and nitrogen addition in a meadow steppe. Nitrogen addition significantly stimulated aboveground biomass and net ecosystem CO2 exchange (NEE), which suggests that nitrogen availability is a primary limiting factor for ecosystem C cycling in the meadow steppe. Water addition had no significant impacts on either ecosystem C exchange or plant biomass, but ecosystem C fluxes showed a strong correlation with early growing season precipitation, rather than whole growing season precipitation, across the 3 experimental years. After we incorporated water addition into the calculation of precipitation regimes, we found that monthly average ecosystem C fluxes correlated more strongly with precipitation frequency than with precipitation amount. These results highlight the importance of precipitation distribution in regulating ecosystem C cycling. Overall, ecosystem C fluxes in the studied ecosystem are highly sensitive to nitrogen deposition, but less sensitive to increased precipitation. PMID:26010888

  20. CAN Canopy Addition of Nitrogen Better Illustrate the Effect of Atmospheric Nitrogen Deposition on Forest Ecosystem?

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Shen, Weijun; Zhu, Shidan; Wan, Shiqiang; Luo, Yiqi; Yan, Junhua; Wang, Keya; Liu, Lei; Dai, Huitang; Li, Peixue; Dai, Keyuan; Zhang, Weixin; Liu, Zhanfeng; Wang, Faming; Kuang, Yuanwen; Li, Zhian; Lin, Yongbiao; Rao, Xingquan; Li, Jiong; Zou, Bi; Cai, Xian; Mo, Jiangming; Zhao, Ping; Ye, Qing; Huang, Jianguo; Fu, Shenglei

    2015-06-01

    Increasing atmospheric nitrogen (N) deposition could profoundly impact community structure and ecosystem functions in forests. However, conventional experiments with understory addition of N (UAN) largely neglect canopy-associated biota and processes and therefore may not realistically simulate atmospheric N deposition to generate reliable impacts on forest ecosystems. Here we, for the first time, designed a novel experiment with canopy addition of N (CAN) vs. UAN and reviewed the merits and pitfalls of the two approaches. The following hypotheses will be tested: i) UAN overestimates the N addition effects on understory and soil processes but underestimates those on canopy-associated biota and processes, ii) with low-level N addition, CAN favors canopy tree species and canopy-dwelling biota and promotes the detritus food web, and iii) with high-level N addition, CAN suppresses canopy tree species and other biota and favors rhizosphere food web. As a long-term comprehensive program, this experiment will provide opportunities for multidisciplinary collaborations, including biogeochemistry, microbiology, zoology, and plant science to examine forest ecosystem responses to atmospheric N deposition.

  1. Effect of Dysprosia Additive on the Consolidation of CeO2 by Spark Plasma Sintering

    SciTech Connect

    K. Choi; R. E. Reavis; D. D. Osterberg; B. J. Jacques; D. P. Butt; R. D. Mariani; D. E. Burkes; Z. A. Munir

    2012-05-01

    The influence of dysprosia addition on the sintering and resulting microstructure of nano-grained CeO2 ceramics was investigated as functions of the spark plasma sintering (SPS) parameters. The addition of Dy2O3 (forming a solid solution) resulted in an increase in relative density and a decrease in grain size. The relative density of samples with Dy2O3 content of 6 and 10 mol% was over 95% when sintered at 1050 C under 500 MPa for holding times as short as 5 minutes. The application of high pressure facilitated the consolidation to relatively high densities with minimal grain growth. Heating rate and holding time, however, had insignificant effect on density but a measurable effect on grain size.

  2. Effect of Ca and Zn additions on the mechanical properties of Mg produced by powder metallurgy

    NASA Astrophysics Data System (ADS)

    Guleryuz, L. F.; Ipek, R.; Arıtman, I.; Karaoglu, S.

    2017-02-01

    Magnesium and its alloys are among important research topics in view of their excellent biocompatibility.In this study mechanical and microstructure properties of hot sintered Mg-Zn-Ca alloys were studied.The effects of the addition of different amounts Ca and Zn were added to the base material has been processed by powder metallurgy method.resulting microstructures densities and compression test behaviors of the Mg-based alloys were studied.Visual inspection using SEM (Scanning Electron Microscope) analyses indicates that the microstructure of the composite is also greatly effected by these parameters. In addition, EDS (Energy Dispersive X-Ray Spectroscopy) analyses were performed for reliable determination of the chemical composition.

  3. Reducing the matrix effects in chemical analysis: fusion of isotope dilution and standard addition methods

    NASA Astrophysics Data System (ADS)

    Pagliano, Enea; Meija, Juris

    2016-04-01

    The combination of isotope dilution and mass spectrometry has become an ubiquitous tool of chemical analysis. Often perceived as one of the most accurate methods of chemical analysis, it is not without shortcomings. Current isotope dilution equations are not capable of fully addressing one of the key problems encountered in chemical analysis: the possible effect of sample matrix on measured isotope ratios. The method of standard addition does compensate for the effect of sample matrix by making sure that all measured solutions have identical composition. While it is impossible to attain such condition in traditional isotope dilution, we present equations which allow for matrix-matching between all measured solutions by fusion of isotope dilution and standard addition methods.

  4. Ring Substituent Effects on the Thiol Addition and Hydrolysis Reactions of N-Arylmaleimides.

    PubMed

    Chen, Yingche; Tsao, Kelvin; De Francesco, Élise; Keillor, Jeffrey W

    2015-12-18

    Maleimide groups are used extensively in bioconjugation reactions, but limited kinetic information is available regarding their thiol addition and hydrolysis reactions. We prepared a series of fluorogenic coumarin maleimide derivatives that differ by the substituent on their maleimide C═C bond. Fluorescence-based kinetic studies of the reaction with β-mercaptoethanol (BME) yielded the second-order rate constants (k2), while pH-rate studies from pH 7 to 9 gave base-catalyzed hydrolysis rate constants (kOH). Linear free-energy relationships were studied through the correlation of log k2 and log kOH to both electronic (σ(+)) and steric (Es(norm)) parameters of the C═C substituent. These correlations revealed the thiol addition reaction is primarily sensitive to the electronic effects, while steric effects dominate the hydrolysis reaction. These mechanistic studies provide the basis for the design of novel bioconjugation reactants or fluorogenic labeling agents.

  5. The additive effects of minoxidil and retinol on human hair growth in vitro.

    PubMed

    Yoo, Hyeon Gyeong; Chang, In-Young; Pyo, Hyun Keol; Kang, Yong Jung; Lee, Seung Ho; Kwon, Oh Sang; Cho, Kwang Hyun; Eun, Hee Chul; Kim, Kyu Han

    2007-01-01

    Minoxidil enhances hair growth by prolonging the anagen phase and induces new hair growth in androgenetic alopecia (AGA), whereas retinol significantly improves scalp skin condition and promotes hair growth. We investigated the combined effects of minoxidil and retinol on human hair growth in vitro and on cultured human dermal papilla cells (DPCs) and epidermal keratinocytes (HaCaT). The combination of minoxidil and retinol additively promoted hair growth in hair follicle organ cultures. In addition, minoxidil plus retinol more effectively elevated phosphorylated Erk, phosphorylated Akt levels, and the Bcl-2/Bax ratio than minoxidil alone in DPCs and HaCaT. We found that the significant hair shaft elongation demonstrated after minoxidil plus retinol treatment would depend on the dual kinetics associated with the activations of Erk- and Akt-dependent pathways and the prevention of apoptosis by increasing the Bcl-2/Bax ratio.

  6. Dextransucrase production using cashew apple juice as substrate: effect of phosphate and yeast extract addition.

    PubMed

    Chagas, Clarice M A; Honorato, Talita L; Pinto, Gustavo A S; Maia, Geraldo A; Rodrigues, Sueli

    2007-05-01

    Cashew apples are considered agriculture excess in the Brazilian Northeast because cashew trees are cultivated primarily with the aim of cashew nut production. In this work, the use of cashew apple juice as a substrate for Leuconostoc mesenteroides cultivation was investigated. The effect of yeast extract and phosphate addition was evaluated using factorial planning tools. Both phosphate and yeast extract addition were significant factors for biomass growth, but had no significant effect on maximum enzyme activity. The enzyme activities found in cashew apple juice assays were at least 3.5 times higher than the activity found in the synthetic medium. Assays with pH control (pH = 6.5) were also carried out. The pH-controlled fermentation enhanced biomass growth, but decreased the enzyme activity. Crude enzyme free of cells produced using cashew apple juice was stable for 16 h at 30 degrees C at a pH of 5.0.

  7. Is the additional greenhouse effect already evident in the current climate?

    PubMed

    Raschke, E

    2001-11-01

    Several greenhouse gases, which are in part or entirely produced by human activities, have accumulated in the atmosphere since approximately the middle of the 19th century. They are assumed to have an additional greenhouse effect causing a further increase of atmospheric temperatures near the ground and a decrease in the layers above approximately 15 km altitude. The currently observed near-surface warming over nearly the entire globe is already considered by a large fraction of our society to be result of this additional greenhouse effect. Complete justification of this assumption is, however, not yet possible, because there are still too many unknowns in our knowledge of participating processes and in our modeling capabilities.

  8. Health Effects Associated with Inhalation Exposure to Diesel Emission Generated with and without CeO2 Nano Fuel Additive

    EPA Science Inventory

    Diesel exhaust (DE) exposure induces adverse cardiopulmonary effects. Addition of nano cerium (Ce) oxide additive to diesel fuel (DECe) increases fuel burning efficiency resulting in altered emission characteristics and potentially altered health effects. We hypothesized that inh...

  9. Effect of Chromium Addition to the Low Temperature Hot Corrosion Resistance of Platinum Modified Aluminide Coatings.

    DTIC Science & Technology

    1985-12-01

    Diffusion aluminide coatings were the first coatings developed for hot corrosion resistance. Aluminum is applied to the surface of the superalloy by a...D.H., "Mechanisms of Formation of Diffusion Aluminide Coatings on Nickel-oase Superalloys , Oxidation of Metals, v. 3, pp. 475-477, 1971. 17. Lehnert...Classification) E.FFECT OF CHROMIUJM ADDITION TO THE LOW TEMPERATURE HOT CORROSION RESISTANCE OF PLATINUM MODIFIED ALUMINIDE COATINGS 2 PERSONAL AUTHOR(S) Dust

  10. Synergistic Effects Between Phosphonium-Alkylphosphate Ionic Liquids and Zinc Dialkyldithiophosphate (ZDDP) as Lubricant Additives

    DOE PAGES

    Qu, Jun; Barnhill, William C.; Luo, Huimin; ...

    2015-07-14

    Unique synergistic effects between phosphonium-alkylphosphate ionic liquids and zinc dialkyldithiophosphate (ZDDP) are discovered when used together as lubricant additives, resulting in significant friction and wear reduction along with distinct tribofilm composition and mechanical properties. The synergism is attributed to the 30-70× higher-than-nominal concentrations of hypothetical new compounds (via anion exchange between IL and ZDDP) on the fluid surface/interface.

  11. UNDERSTANDING THE EFFECTS OF SURFACTANT ADDITION ON RHEOLOGY USING LASER SCANNING CONFOCAL MICROSCOPY

    SciTech Connect

    White, T

    2007-05-08

    The effectiveness of three dispersants to modify rheology was examined using rheology measurements and laser scanning confocal microscopy (LSCM) in simulated waste solutions. All of the dispersants lowered the yield stress of the slurries below the baseline samples. The rheology curves were fitted reasonably to a Bingham Plastic model. The three-dimensional LSCM images of simulants showed distinct aggregates were greatly reduced after the addition of dispersants leading to a lowering of the yield stress of the simulated waste slurry solutions.

  12. Effect of Grape Pomace Powder Addition on TBARS and Color of Cooked Pork Sausages during Storage.

    PubMed

    Ryu, Kyeong Seon; Shim, Kwan Seob; Shin, Daekeun

    2014-01-01

    To determine the effects of grape skin and seed pomace (GSP) additions on the lipid oxidation susceptibility and the color change of cooked pork sausages, the chemical characteristics of GSP itself and the addition for two different levels of GSP (0.5 and 1.0% GSP, respectively) to sausages were examined. Both the redness and blueness of the GSP were significantly reduced as the pH level was increased from 5 to 7, but a reverse result was determined in the color tint and yellowness (p<0.05). The GSP polyphenol and flavonoid contents were influenced by the percentages of methanol solvents, and more flavonoids were established when 100% of methanol was applied as a solvent to the GSP. But, similar results were not observed in the polyphenol of GSP. In cooked pork sausages, significant decreases in the lightness and redness were found in both the 0.5% and 1.0% of GSP sausages during the storage period (p<0.05). However, an incompatible effect was observed in terms of yellowness, which increased as compared to the control sausage after 6 days of storage. The 0.5% addition of GSP decreased the levels of TBARS (p<0.05), but the ability of GSP to minimize lipid oxidation was not dose dependent. Therefore, the results indicated that the GSP is an efficient suppressor of lipid oxidation and has latent effects as a natural antioxidant when 0.5% of GSP is added to the cooked pork sausages.

  13. Effect of additives on gas-phase catalysis with immobilised Thermoanaerobacter species alcohol dehydrogenase (ADH T).

    PubMed

    Trivedi, A H; Spiess, A C; Daussmann, T; Büchs, J

    2006-07-01

    This paper presents a strategy for preparing an efficient immobilised alcohol dehydrogenase preparation for a gas-phase reaction. The effects of additives such as buffers and sucrose on the immobilisation efficiency (residual activity and protein loading) and on the gas-phase reaction efficiency (initial reaction rate and half-life) of Thermoanaerobacter sp. alcohol dehydrogenase were studied. The reduction of acetophenone to 1-phenylethanol under in situ cofactor regeneration using isopropanol as co-substrate was used as a model reaction at fixed reaction conditions (temperature and thermodynamic activities). A strongly enhanced thermostability of the enzyme in the gas-phase reaction was achieved when the enzyme was immobilised with 50 mM phosphate buffer (pH 7) containing sucrose five times the protein amount (on weight/weight basis). This resulted in a remarkable productivity of 200 g L(-1) day(-1) even at non-optimised reaction conditions. The interaction of additives with the enzyme and water affects the immobilisation and gas-phase efficiencies of the enzyme. However, it was not possible to predict the effect of additives on the gas-phase reaction efficiency even after knowing their effect on the immobilisation efficiency.

  14. Effect of Mo Addition on the Transformation Stasis Phenomenon During the Isothermal Formation of Bainitic Ferrite

    NASA Astrophysics Data System (ADS)

    Zhang, Congyu; Chen, Hao; Zhu, Kangying; Zhang, Chi; Yang, Zhigang

    2016-12-01

    The effect of Mo addition on the transformation stasis (TS) phenomenon during bainitic transformation has been investigated in Fe-0.2C-1.5Mn-1.5Si-(0.2, 1.5, 3)Mo (wt pct) alloys. Both diffusionless and diffusional models failed in predicting the TS that is strongly affected by Mo concentration in experiment. The Gibbs energy balance approach could capture TS in alloys with 0.2 and 1.5 wt pct Mo, but significantly underestimate bainite fraction at stasis for alloy with 3 wt pct Mo, which is deduced to arise from the so-called anti-coupled solute drag effect.

  15. Geomagnetic Storm Main Phase effect on the Equatorial Ionosphere as measured from GPS observations at Ile-Ife

    NASA Astrophysics Data System (ADS)

    Olabode, Ayomide; Ariyibi, Emmanuel

    2016-07-01

    The effect of the main phase of two intense geomagnetic storm events which occurred on August 5-6 and September 26-27, 2011 on the equatorial ionosphere have been investigated using Global Positioning System (GPS) data obtained from an Ile-Ife station (geomagnetic lat. 9.84°N, long. 77.25°E). The WinTEC-P and GPS-TEC analysis software programs were used to process the GPS data to obtain Total Electron Content (TEC) and Scintillation Index (S4). TEC profiles during the main phase of the two geomagnetically disturbed days were compared with quiet time average profiles to examine the response of the equatorial ionosphere. International Reference Ionosphere (IRI) 2012 TEC model was also obtained from Virtual Ionosphere, Thermosphere, Mesosphere Observatory (VITMO) and the extents of deviation from measured GPS-derived TEC were examined for the main phase of the storm events. The results showed that the intensity of both storm events during the main phase which occurred at night-time correlated well with a strong southward direction of the z-component of the Interplanetary Magnetic Field (IMF-Bz) and Solar Wind Speed (Vsw), with the Disturbance storm time (Dst) profile showing multiple step development. TEC depletion was observed during the main phase of the August 5-6, 2011 storm event with TEC recording a maximum value of 9.31 TECU. A maximum TEC value of 55.8 TECU was recorded during the main phase of the September 26-27, 2011 storm event depicting TEC enhancement. Significant scintillation index value of 0.57 was observed when the main phase started on August 5-6, 2011 followed by a prolonged suppression while there was less significant scintillation impact on September 26-27, 2011 with a maximum value of 0.33. The study concluded that the intensification of the ring current during the main phase of geomagnetic storm events was responsible for the intensity of the storm events causing large variations in TEC and significant scintillation phenomenon.

  16. Non-additive effects of herbivores and pollinators on Erysimum mediohispanicum (Cruciferae) fitness.

    PubMed

    Gómez, José M

    2005-04-01

    In this study, the non-additivity of effects of herbivores and pollinator on fitness of the plant Erysimum mediohispanicum (Cruciferae) has been experimentally tested. The abundance and diversity of the pollinator assemblage of plants excluded from and exposed to mammalian herbivores, and the combined effect of pollinators and herbivores on plant reproduction were determined over a period of 2 years. Pollinator abundance was higher and diversity was lower on plants excluded from herbivores. Furthermore, the experimental exclusions demonstrated that both pollinators and herbivores affected plant fitness, but their effects were not independent. Herbivores only had a detrimental effect on plant fitness when pollinators were present. Similarly, pollinators enhanced fitness only when herbivores were excluded. This outcome demonstrates that the importance of pollinators for plant fitness depends on the occurrence of herbivores, and suggests that herbivores may hamper pollinator-mediated adaptation in plants.

  17. Effects of nitrogen and phosphorus additions on soil methane uptake in disturbed forests

    NASA Astrophysics Data System (ADS)

    Zheng, Mianhai; Zhang, Tao; Liu, Lei; Zhang, Wei; Lu, Xiankai; Mo, Jiangming

    2016-12-01

    Atmospheric nitrogen (N) deposition is generally thought to suppress soil methane (CH4) uptake in natural forests, and phosphorus (P) input may alleviate this negative effect. However, it remains unclear how N and P inputs control soil CH4 uptake in disturbed forests. In this study, soil CH4 uptake rates were measured in two disturbed forests, including a secondary forest (with previous, but not recent, disturbance) and a plantation forest (with recent continuous disturbance), in southern China for 34 months of N and/or P additions: control, N addition (150 kg N ha-1 yr-1), P addition (150 kg P ha-1 yr-1), and NP addition (150 kg N ha-1 yr-1 plus 150 kg P ha-1 yr-1). Mean CH4 uptake rate in control plots was significantly higher in the secondary forest (24.40 ± 0.81 µg CH4-C m-2 h-1) than in the plantation forest (17.07 ± 0.70 µg CH4-C m-2 h-1). CH4 uptake rate had negative relationships with soil water-filled pore space in both forests. In the secondary forest, N, P, and NP additions significantly decreased CH4 uptake by 39.7%, 27.8%, and 37.6%, respectively, but had no significant effects in the plantation forest, indicating that P input does not alleviate the suppression of CH4 uptake by N deposition. Taken together, our findings suggest that reducing anthropogenic disturbance, including harvesting of forest floor, and anthropogenic N and P inputs will increase soil CH4 uptake in disturbed forests, which is important in view of the increased trends in global warming during recent decades.

  18. Potential Additives to Promote Seal Swell in Synthetic Fuels and Their Effect on Thermal Stability

    SciTech Connect

    Link, D.D.; Gormley, R.J.; Baltrus, J.P.; Anderson, R.R.; Zandhuis, P.H.

    2008-03-01

    Synthetic fuels derived from the Fischer–Tropsch (F-T) process using natural gas or coal-derived synthesis gas as feedstocks can be used for powering ground vehicles, aircraft, and ships. Because of their chemical and physical properties, F-T fuels will probably require additives in order to meet specifications with respect to lubricity and seal swell capability for use in ground and air vehicles. Using both experimental and computational studies, the propensity of certain species to enhance the seal swell characteristics of synthetic fuels and surrogates has been determined, and promising additives have been identified. Important structural characteristics for potential additives, namely an aromatic ring along with a polar constituent, are described. The thermal stability of synthetic and surrogate fuels containing the single-component additive benzyl alcohol, which is representative of this structural class, has been determined by batch stressing of the mixtures at 350 °C for up to 12 h. Synthetic fuels spiked with benzyl alcohol at concentrations (vol %) of 1.0, 0.75, and 0.5 have demonstrated the ability to swell nitrile rubber o-rings to a comparable degree as petroleum jet fuel. Further, batch reactor studies have shown that addition of benzyl alcohol does not degrade the thermal oxidative stability of the fuel based on gravimetric analysis of the solid deposits after stressing. GC-MS was used to characterize the products from thermal stressing of neat and additized surrogate jet fuel, and their compositions were compared with respect to the creation of certain species and their potential effect on deposition.

  19. Synergistic effect between nano-ceramic lubricating additives and electroless deposited Ni-W-P coating

    NASA Astrophysics Data System (ADS)

    Chen, Min; Cheng, Wushan; Zhao, Zuxin; Huang, Xiaobo

    2013-01-01

    The major solving ways for the material wear are surface modification and lubrication. Currently, the researches at home and abroad are all limited to the single study of either nano-lubricating oil additive or electroless deposited coating. The surface coating has high hardness and high wear resistance, however, the friction reduction performance of the coating with high hardness is not good, the thickness of the coating is limited, and the coating can not regenerate after wearing. The nano-lubricating additives have good tribological performance and self-repair function, but under heavy load, the self-repair rate to the worn surface with the nano-additives is smaller than the wearing rate of the friction pair. To solve the above problems, the Ni-W-P alloy coating and deposition process with excellent anti-wear, and suitable for industrial application were developed, the optimum bath composition and process can be obtained by studying the influence of the bath composition, temperature and PH value to the deposition rate and the plating solution stability. The tribological properties as well as anti-wear and friction reduction mechanism of wear self-repair nano-ceramic lubricating additives are also studied. The ring-block abrasion testing machine and energy dispersive spectrometer are used to explore the internal relation between the coating and the nano-lubricating oil additives, and the tribology mechanism, to seek the synergetic effect between the two. The test results show that the wear resistance of Ni-W-P alloy coating (with heat treatment and in oil with nano-ceramic additives) has increased hundreds times than 45 steel as the metal substrate in basic oil, the friction reduction performance is improved. This research breaks through the bottleneck of previous separate research of the above-mentioned two methods, and explores the combination use of the two methods in industrial field.

  20. Effect of relative humidity and additives on the reaction of sulfur dioxide with calcium hydroxide

    SciTech Connect

    Ruiz-Alsop, R.N.

    1986-01-01

    The objective of this research was to investigate the effect of process variables and additives on the reaction rate of Ca(OH)/sub 2/ with SO/sub 2/ at conditions similar to these encountered in the bag filters used to collect solids following flue gas desulfurization by spray drying. The effect of Ca(OH)/sub 2/ loading, temperature, relative humidity, and inlet SO/sub 2/ concentration were investigated. Of these variables, relative humidity showed the greatest impact on the reaction rate. The effect of small amounts of additives were also investigated. Of the additives tried (buffer acids, organic deliquescents, and inorganic deliquescents) deliquescent salts were the only additives that improved reactivity. A shrinking core model with zero order kinetics in SO/sub 2/ was used to model experimental data. An empirical correlation was included in the model to account for shape and surface roughness of the Ca(OH)/sub 2/ particles. The diffusion coefficient of the SO/sub 2/ through the product layer was found to increase linearly with relative humidity, and the kinetic rate constant increases exponentially with relative humidity. With a few exceptions the model was able to predict the experimental data within the margin of experimental error (+/- 10%). At high relative humidity and/or high SO/sub 2/ concentration, reaction kinetics control the overall reaction rate, while at low relative humidity and/or low SO/sub 2/ concentration, SO/sub 2/ diffusion through the product layer controls the rate. The reaction solids were characterized by scanning electron microscopy, powder x-ray diffraction, Coulter counter size distribution BET (N/sub 2/) surface area, energy dispersive spectrometry, and differential scanning calorimetry.

  1. Effects of emulsifier addition on the crystallization and melting behavior of palm olein and coconut oil.

    PubMed

    Maruyama, Jessica Mayumi; Soares, Fabiana Andreia Schafer De Martini; D'Agostinho, Natalia Roque; Gonçalves, Maria Inês Almeida; Gioielli, Luiz Antonio; da Silva, Roberta Claro

    2014-03-12

    Two commercial emulsifiers (EM1 and EM2), containing predominantly monoacylglycerols (MAGs), were added in proportiond of 1.0 and 3.0% (w/w) to coconut oil and palm olein. EM1 consisted of approximately 90% MAGs, whereas EM2 consisted of approximately 50% MAGs. The crystallization behavior of these systems was evaluated by differential scanning calorimetry (DSC) and microscopy under polarized light. On the basis of DSC results, it was clear that the addition of EM2 accelerated the crystallization of coconut oil and delayed the crystallization of palm olein. In both oils EM2 addition led to the formation of smaller spherulites, and these effects improved the possibilities for using these fats as ingredients. In coconut oil the spherulites were maintained even at higher temperatures (20 °C). The addition of EM1 to coconut oil changed the crystallization pattern. In palm olein, the addition of 3.0% (w/w) of this emulsifier altered the pattern of crystallization of this fat.

  2. Soluble organic additive effects on stress development during drying of calcium carbonate suspensions.

    PubMed

    Wedin, Pär; Lewis, Jennifer A; Bergström, Lennart

    2005-10-01

    The effect of polymer, plasticizer, and surfactant additives on stress development during drying of calcium carbonate particulate coatings was studied using a controlled-environment apparatus that simultaneously monitors drying stress, weight loss, and relative humidity. We found that the calcium carbonate coatings display a drying stress evolution typical of granular films, which is characterized by a sharp capillary-induced stress rise followed by a rapid stress relaxation. The addition of a soluble polymer to the CaCO3 suspension resulted in a two-stage stress evolution process. The initial stress rise stems from capillary-pressure-induced stresses within the film, while the second, larger stress rise occurs due to solidification and shrinkage of the polymeric species. Measurements on the corresponding pure polymer solutions established a clear correlation between the magnitude of residual stress in both the polymer and CaCO3-polymer films to the physical properties of the polymer phase, i.e. its glass transition temperature, T(g), and Young's modulus. The addition of small organic molecules can reduce the residual stress observed in the CaCO3-polymer films; e.g., glycerol, which acts as a plasticizer, reduces the drying stress by lowering T(g), while surfactant additions reduce the surface tension of the liquid phase, and, hence, the magnitude of the capillary pressure within the film.

  3. Nitrogen-addition effects on leaf traits and photosynthetic carbon gain of boreal forest understory shrubs.

    PubMed

    Palmroth, Sari; Bach, Lisbet Holm; Nordin, Annika; Palmqvist, Kristin

    2014-06-01

    Boreal coniferous forests are characterized by fairly open canopies where understory vegetation is an important component of ecosystem C and N cycling. We used an ecophysiological approach to study the effects of N additions on uptake and partitioning of C and N in two dominant understory shrubs: deciduous Vaccinium myrtillus in a Picea abies stand and evergreen Vaccinium vitis-idaea in a Pinus sylvestris stand in northern Sweden. N was added to these stands for 16 and 8 years, respectively, at rates of 0, 12.5, and 50 kg N ha(-1) year(-1). N addition at the highest rate increased foliar N and chlorophyll concentrations in both understory species. Canopy cover of P. abies also increased, decreasing light availability and leaf mass per area of V. myrtillus. Among leaves of either shrub, foliar N content did not explain variation in light-saturated CO2 exchange rates. Instead photosynthetic capacity varied with stomatal conductance possibly reflecting plant hydraulic properties and within-site variation in water availability. Moreover, likely due to increased shading under P. abies and due to water limitations in the sandy soil under P. sylvestris, individuals of the two shrubs did not increase their biomass or shift their allocation between above- and belowground parts in response to N additions. Altogether, our results indicate that the understory shrubs in these systems show little response to N additions in terms of photosynthetic physiology or growth and that changes in their performance are mostly associated with responses of the tree canopy.

  4. Effect of additives on tribochemical stability of greases with easter base oil

    SciTech Connect

    Nikonorov, E.M.; Demina, L.V.; Skryabina, T.G.; Sosulina, L.N.

    1984-03-01

    This article investigates the possibility of improving the tribochemical stability of soap-base grease formulated with polyol ester oils, by the use of additives of the phenol and amine types. Model greases formulated with a pentaerythritol ester (PET) and the polyester PAK, taken in a 9:1 ratio, were examined. The tribochemical stability of the greases was evaluated according to the rate of conversion of their dispersion medium in a rolling friction zone. The rate of additive exhaustion was evaluated by analogy with the rate of triboconversion of the dispersion medium. The additives used were phenyl-..cap alpha..-naphthylamine (PAN), diphenylamine (DPA), 2, 6-di-tert-butyl-p-cresol (ionol), a technical-grade dialkylated diphenylamine (DAT), and mixtures of the inhibitors. It is determined that the greatest effect in increasing the tribochemical stability is achieved by the introduction of combinations of additives: DAT + ionol (in Li and cCa greases) and PAN + DAT (in cCa grease).

  5. Effect of additives on the anisotropic etching of silicon by using a TMAH based solution

    NASA Astrophysics Data System (ADS)

    Jun, Ki-Hwa; Kim, Bum-Joon; Kim, Jung-Sik

    2015-09-01

    In this study, the anisotropic etching properties of single crystal silicon were examined using a tetramethyl ammonium hydroxide (TMAH). The variations in the Si etching rate and surface morphology at different etching temperatures and TMAH concentrations were evaluated. The effects of different additives were also examined. As the THAM concentration (10-25 wt. %) decreased, the etching rate increased from 10 μm/h to 70 μm/h at temperatures between 70°C and 90°C. On the other hand, the etched surface roughness became degraded as the hillock density and corner undercut ratio increased. To solve these problems, four additives, pyrazine, ammonium persulfate (AP), ammonium hydrogen sulfate (AHS), and isopropyl alcohol (IPA), were added to the TMAH solution. The experimental results showed that these additives play an important role in increasing the etching rate up to 10-20%. The etched surface was also improved significantly by the decreased hillock density on the surface. The addition of IPA to the TMAH solution showed excellent results in improving the etched surface flatness and the undercutting compensation. On the other hand, one of the characteristics of IPA is the decrease in etching rate with increasing amount of IPA. [Figure not available: see fulltext.

  6. Effect of dietary addition of seaweed and licorice on the immune performance of pigs.

    PubMed

    Katayama, Masafumi; Fukuda, Tomokazu; Okamura, Toshihiro; Suzuki, Eisaku; Tamura, Katsuo; Shimizu, Yuuko; Suda, Yoshihito; Suzuki, Keiichi

    2011-04-01

    In pig production, dietary additive antibiotics are usually used for growth stimulation and disease prevention, although there is public concern about the increased incidence of resistant antibiotics and food safety. It is possible that such antibiotics might be replaced by naturally derived products such as seaweed and licorice. In this study, we evaluated the effect of dietary addition of seaweed and licorice on enhancing the immune function in swine. The animals of each group (eight animals per group) were sensitized at day 42 and 49, and the immunoglobulin production and the expression of cytokines were detected by the ELISA and real-time PCR. As the results, saliva IgA production of the seaweed-treated group increased around five times compared to that of control (day 56). Delayed hypersensitivity reaction and IgG production of the seaweed-treated group increased around 1.8-2.0 times. In addition, enhanced saliva IgA production was detected at day 50 (around two times) and day 51 (around five times) by the licorice treatment, and lower expression level of tumor necrosis factor-α messenger RNA at day 51 (around 1/25) was observed in the licorice treatment. We conclude that the replacement of antibiotics by naturally derived dietary additives might be feasible for immune system enhancement.

  7. Long term effect of MnO2 powder addition on nitrogen removal by anammox process.

    PubMed

    Qiao, Sen; Bi, Zhen; Zhou, Jiti; Cheng, Yingjun; Zhang, Jie; Bhatti, Zafar

    2012-11-01

    This study examined long-term effect of MnO(2) powder (average diameter of 4-7 μm) on nitrogen removal in anammox process. Two lab-scale up-flow anammox reactors were operated for 380 days, one with and one without MnO(2) powder addition. During the period when only substrate concentrations varied, the maximum nitrogen removal rate in the reactor with MnO(2) addition reached 920.9 g-N/m(3)/d. This value was 2-folds higher than that (464.6 g-N/m(3)/d) of the reactor without MnO(2) addition. The crude enzyme activities of the anammox biomass from the two reactors was measured as 0.531±0.019 and 0.298±0.007 μmol cytochrome c reduced/mg protein/min, respectively. Transmission electron microscopy observation demonstrated more undefined particles existing inside anammox bacterial cell in the reactor with MnO(2) powder addition. Furthermore, filament-like structures inside anammoxosome were observed, which formed a net-like structure with particles as the connecting nodes. The experiment results demonstrated that MnO(2) improved nitrogen removal performance of anammox process.

  8. Effect of the Additives on the Desulphurization Rate of Flash Hydrated and Agglomerated CFB Fly Ash

    NASA Astrophysics Data System (ADS)

    Li, D. X.; Li, H. L.; Xu, M.; Lu, J. F.; Liu, Q.; Zhang, J. S.; Yue, G. X.

    CFB fly ash from separators was mixed with water or the mixture of water and additives under the temperature of 363K by use of a blender. Then, this compound of fly ash and water or additives was pumped into a CFB combustion chamber by a sludge pump. Because the temperature of flue gas was high in CFB, the fly ash was hydrated fast and agglomerated in the same time. Through this process, the size of agglomerating fly ash is larger than the original particle and the relative residence time of agglomerated fly ash in CFB becomes longer. Therefore, the rate of utility of calcium in fly ash improves and the content of carbon in fly ash decreases. This results in a low Ca/S and low operational cost for CFB boiler. The additive is one key factor, which affects the rate of desulfurization of agglomerated fly ash. Effect of different additives on rate of desulfurization is not same. Cement and limestone are beneficiated to sulfur removal of agglomerated fly ash, but sodium silicate does not devote to the rate of sulfur removal of agglomerated fly ash.

  9. Rheological behavior and organoleptic effects of ovalbumin addition in yogurt mousse production.

    PubMed

    Menéndez, M; Paredes, B; Iglesias, O; Rendueles, M; Díaz, M

    2006-03-01

    Yogurt mousse is a novel, high added-value dairy product that has been well received by the market. This paper presents a study of the effect of the addition of ovalbumin to the product on its rheological and organoleptic qualities. The ovalbumin was previously separated from egg white with a high grade of purity using an ion exchange resin synthesized by the authors. Diverse rheological tests at different temperatures and corresponding sensorial assessments were conducted to compare samples without and with added ovalbumin. The obtained results confirm that the product is viscoelastic and combines the properties of foams and emulsions; the elastic component is greater than the viscous component. Moreover, at temperatures ranging from 5 to 15 degrees C, a usual interval of consumption, the product behaves rheologically in a similar way. Conversely, the addition of ovalbumin under the assayed conditions also makes the elastic character of the product increase at a given temperature. Finally, the sensorial assessment tests and determinations of stability and volume yield enabled us to verify that the addition of ovalbumin at an amount of 1.3% hardly alters the stability, resistance to shear stress, or the texture and improves the degree of foaming. Therefore, the product with additive is of good commercial quality.

  10. EFFECTS OF ADDITION RATE AND ACID MATRIX ON THE DESTRUCTION OF AMMONIUM BY THE SEMI-CONTINUOUS ADDITION OF SODIUM NITRITE DURING EVAPORATION

    SciTech Connect

    Kyser, E

    2007-08-27

    The destruction of ammonium by the semi-continuous addition of sodium nitrite during acidic evaporation can be achieved with a wide range of waste compositions. The efficiency of nitrite utilization for ammonium destruction was observed to vary from less than 20% to 60% depending on operating conditions. The effects of nitric acid concentration and nitrite addition rate are dominant factors that affect the efficiency of nitrite utilization for ammonium destruction. Reducing the acid concentration by performing acid recovery via steam stripping prior to performing nitrite destruction of ammonium will require more nitrite due to the low destruction efficiency. The scale-up of the baseline rate nitrite addition rate from the 100 mL to the 1600 gallon batch size has significant uncertainty and poses the risk of lower efficiency at the plant scale. Experience with plant scale processing will improve confidence in the application of nitrite destruction of ammonium to different waste streams.

  11. Combined effect of sourdough lactic acid bacteria and additives on bread firmness and staling.

    PubMed

    Corsetti, A; Gobbetti, M; De Marco, B; Balestrieri, F; Paoletti, F; Russi, L; Rossi, J

    2000-07-01

    The effect of various sourdoughs and additives on bread firmness and staling was studied. Compared to the bread produced with Saccharomyces cerevisiae 141, the chemical acidification of dough fermented by S. cerevisiae 141 or the use of sourdoughs increased the volume of the breads. Only sourdough fermentation was effective in delaying starch retrogradation. The effect depended on the level of acidification and on the lactic acid bacteria strain. The effect of sourdough made of S. cerevisiae 141-Lactobacillus sanfranciscensis 57-Lactobacillus plantarum 13 was improved when fungal alpha-amylase or amylolytic strains such as L. amylovorus CNBL1008 or engineered L. sanfranciscensis CB1 Amy were added. When pentosans or pentosans, endoxylanase enzyme, and L. hilgardii S32 were added to the same sourdough, a greater delay of the bread firmness and staling was found. When pentosans were in part hydrolyzed by the endoxylanase enzyme, the bread also had the highest titratable acidity, due to the fermentation of pentoses by L. hilgardii S32. The addition of the bacterial protease to the sourdough increased the bread firmness and staling.

  12. Additive and non-additive effects of mixtures of short-acting intravenous anaesthetic agents and their significance for theories of anaesthesia

    PubMed Central

    Richards, C.D.; White, Ann E.

    1981-01-01

    1 The potency of a series of short-acting anaesthetics was established by measuring the duration of the loss of righting reflex following a single bolus injection into the tail vein of male Wistar rats. The agents were, in order of potency, etomidate, alphaxalone, methohexitone, alphadalone acetate and propanidid. 2 The potency of binary mixtures of these agents was also assessed to see whether the anaesthetic effects of different agents were additive as classical theories of anaesthesia suggest. Mixtures of alphaxalone and alphadalone acetate, alphaxalone and propanidid and methohexitone and propanidid all showed simple additive effects. Mixtures of alphaxalone and etomidate and of alphaxalone and methohexitone showed a greater potency than would be expected if their effects were simply additive. Mixtures of etomidate and methohexitone were not examined. 3 Mixtures of alphaxalone and either methohexitone or pentobarbitone produced a greater depression of synaptic transmission in in vitro preparations of guinea-pig olfactory cortex than would have been expected from the sum of the activities of the individual anaesthetics. Other combinations of anaesthetics did not show similar effects although the interaction between alphaxalone and etomidate was not examined. 4 Neither alphaxalone nor pentobarbitone affected the membrane: buffer partition coefficient of the other for a model membrane system. 5 These results are interpreted as evidence against the classical unitary hypotheses of anaesthetic action based on correlations of anaesthetic potency with lipid solubility and as supporting the view that different anaesthetics act on different structures in the neuronal membranes to produce anaesthesia. PMID:6268237

  13. Genetic expectations of quantitative trait loci main and interaction effects obtained with the triple testcross design and their relevance for the analysis of heterosis.

    PubMed

    Melchinger, A E; Utz, H F; Schön, C C

    2008-04-01

    Interpretation of experimental results from quantitative trait loci (QTL) mapping studies on the predominant type of gene action can be severely affected by the choice of statistical model, experimental design, and provision of epistasis. In this study, we derive quantitative genetic expectations of (i) QTL effects obtained from one-dimensional genome scans with the triple testcross (TTC) design and (ii) pairwise interactions between marker loci using two-way analyses of variance (ANOVA) under the F(2)- and the F(infinity)-metric model. The theoretical results show that genetic expectations of QTL effects estimated with the TTC design are complex, comprising both main and epistatic effects, and that genetic expectations of two-way marker interactions are not straightforward extensions of effects estimated in one-dimensional scans. We also demonstrate that the TTC design can partially overcome the limitations of the design III in separating QTL main effects and their epistatic interactions in the analysis of heterosis and that dominance x additive epistatic interactions of individual QTL with the genetic background can be estimated with a one-dimensional genome scan. Furthermore, we present genetic expectations of variance components for the analysis of TTC progeny tested in a split-plot design, assuming digenic epistasis and arbitrary linkage.

  14. Effects of feed additives on rumen and blood profiles during a starch and fructose challenge.

    PubMed

    Golder, H M; Celi, P; Rabiee, A R; Lean, I J

    2014-02-01

    We evaluated the effect of feed additives on the risk of ruminal acidosis in Holstein heifers (n = 40) fed starch and fructose in a challenge study. Heifers were randomly allocated to feed additive groups (n = 8 heifers/group): (1) control (no additives); (2) virginiamycin (VM); (3) monensin + tylosin (MT); (4) monensin + live yeast (MLY); and (5) sodium bicarbonate + magnesium oxide (BUF). Heifers were fed 2.5% of body weight (BW) dry matter intake (DMI) per day of a total mixed ration (62:38 forage:concentrate) and feed additives for a 20-d adaptation period. Fructose (0.1% of BW/d) was included for the last 10d of the adaptation period. On d 21, heifers were fed to target a DMI of 1.0% of BW of wheat, fructose at 0.2% of BW, and their feed additives. Rumen fluid samples obtained by stomach tube and blood samples were collected weekly as well as during a 3.6-h period on challenge day (d 21). Virginiamycin and BUF groups maintained a consistently high DMI across the 20-d adaptation period. The MLY heifers had low DMI of the challenge ration. Average daily gain and feed conversion ratio were not affected by feed additives. All rumen and plasma measures changed weekly over adaptation and over the challenge sampling period with the exception of rumen total lactate and histamine concentrations, plasma oxidative stress index, and ceruloplasmin. Substantial within- and between-group variation was observed in rumen and plasma profiles at challenge sampling. No significant group changes were observed in rumen total volatile fatty acids, propionate, acetate-to-propionate ratio, isobutyrate, caproate, isovalerate, total lactate, d- and l-lactate, and pH measures on challenge day. Acetate concentration was increased in the BUF and control groups on challenge day. Butyrate concentration was lower in the MLY and MT groups compared with other groups at challenge. Valerate concentrations were lowest in the control, VM, and BUF groups and lactate concentrations were numerically

  15. Effect of alcohol addition on the movement of petroleum hydrocarbon fuels in soil.

    PubMed

    Adam, Gillian; Gamoh, Keiji; Morris, David G; Duncan, Harry

    2002-03-08

    Groundwater contamination by fuel spills from aboveground and underground storage tanks has been of growing concern in recent years. This problem has been magnified by the addition of oxygenates, such as ethanol and methyl-tertiary-butyl ether (MTBE) to fuels to reduce vehicular emissions to the atmosphere. These additives, although beneficial in reducing atmospheric pollution, may, however, increase groundwater contamination due to the co-solvency of petroleum hydrocarbons and by the provision of a preferential substrate for microbial utilisation. With the introduction of ethanol to diesel fuel imminent and the move away from MTBE use in many states of the USA, the environmental implications associated with ethanol additive fuels must be thoroughly investigated. Diesel fuel movement was followed in a 1-m soil column and the effect of ethanol addition to diesel fuel on this movement determined. The addition of 5% ethanol to diesel fuel was found to enhance the downward migration of the diesel fuel components, thus increasing the risk of groundwater contamination. A novel method using soil packed HPLC columns allowed the influence of ethanol on individual aromatic hydrocarbon movement to be studied. The levels of ethanol addition investigated were at the current additive level (approx. 25%) for ethanol additive fuels in Brazil and values above (50%) and below (10%) this level. An aqueous ethanol concentration above 10% was required for any movement to occur. At 25% aqueous ethanol, the majority of hydrocarbons were mobilised and the retention behaviour of the soil column lessened. At 50% aqueous ethanol, all the hydrocarbons were found to move unimpeded through the columns. The retention behaviour of the soil was found to change significantly when both organic matter content and silt/clay content was reduced. Unexpectedly, sandy soil with low organic matter and low silt/clay was found to have a retentive behaviour similar to sandy subsoil with moderate silt

  16. Effect of combined herbal feed additives on methane, total gas production and rumen fermentation

    PubMed Central

    Chaturvedi, Indu; Dutta, Tapas Kumar; Singh, Pawan Kumar; Sharma, Ashwani

    2015-01-01

    The present study was to evaluate effect of herbal feed additives on methane and total gas production during the rumen fermentation for environment and animal health concern. Different parts of the five medicinal plants were selected such as leaf and small stems of Ocimum sanctum (Tulsi), roots of Curcuma longa (Haldi), fruits of Emblica officinalis (Amla), leaves of Azadirachta indica (Neem) and leaves and small stem of Clerodendrum phlomidis (Arni) for our study. Addition of different herbal additive combinations did not influence IVDMD and total gas production however methane production (mg/g of substrate DM) was significantly (P<0.05) reduced in Amla: Neem and Neem: Arni combinations. Total nitrogen significantly (P<0.01) increased in the combinations of Tulsi: Haldi and Amla: Neem. TCA–ppt-N is significantly (P<0.01) increased in Tulsi: Haldi, Haldi: Amla, Amla: Neem and Neem: Arni however NH3-N (mg/dl) significantly decreased in all treatments. We conclude that the screening of plant combinations, Amla: Neem and Neem: Arni have potential to decrease methane production and our herbal feed supplements have no side-effects on the ruminant in small amount. PMID:26124571

  17. Effects of native species diversity and resource additions on invader impact.

    PubMed

    Maron, John L; Marler, Marilyn

    2008-07-01

    Theory and empirical work have demonstrated that diverse communities can inhibit invasion. Yet, it is unclear how diversity influences invader impact, how impact varies among exotics, and what the relative importance of diversity is versus extrinsic factors that themselves can influence invasion. To address these issues, we established plant assemblages that varied in native species and functional richness and crossed this gradient in diversity with resource (water) addition. Identical assemblages were either uninvaded or invaded with one of three exotic forbs: spotted knapweed (Centaurea maculosa), dalmatian toadflax (Linaria dalmatica), or sulfur cinquefoil (Potentilla recta). To determine impacts, we measured the effects of exotics on native biomass and, for spotted knapweed, on soil moisture and nitrogen levels. Assemblages with high species richness were less invaded and less impacted than less diverse assemblages. Impact scaled with exotic biomass; spotted knapweed had the largest impact on native biomass compared with the other exotics. Although invasion depressed native biomass, the net result was to increase total community yield. Water addition increased invasibility (for knapweed only) but had no effect on invader impact. Together, these results suggest that diversity inhibits invasion and reduces impact more than resource additions facilitate invasion or impact.

  18. Effect of medium additives during liquid storage on developmental competence of in vitro matured bovine oocytes.

    PubMed

    Suttirojpattana, Tayita; Somfai, Tamas; Matoba, Satoko; Parnpai, Rangsun; Nagai, Takashi; Geshi, Masaya

    2017-02-01

    Our aim was to improve the developmental competence of bovine oocytes during their liquid storage by using additives. In vitro matured oocytes were stored for 20 h at 25°C in HEPES buffered TCM 199 medium (base medium). After storage, in vitro embryo development after in vitro fertilization was compared to those of non-stored (control) ones. Addition of 10% (v/v) newborn calf serum or 10.27 mmol/L pyruvate alone to the base medium did not improve blastocyst formation rates in stored oocytes; however, their simultaneous addition significantly improved the rate compared with those stored in base medium (P < 0.05). Supplementation of the holding medium with dithiothreitol (DTT) at any concentrations did not improve embryo development from stored oocytes. Although supplementation with cyclosporine A (CsA) significantly reduced apoptosis and membrane damage rates during storage, it did not improve the developmental competence of oocytes. 1,2-bis(2-aminophenoxy) ethane N,N,N',N'-tetraacetic acid tetrakis-acetoxymethyl ester and ruthenium red had no effect on oocyte apoptotic rates. Blastocyst formation rates in all stored groups remained significantly lower than that of the control. In conclusion, pyruvate and serum had a synergic effect to moderate the reduction of oocyte quality during storage, whereas mitochondrial membrane pore inhibitor CsA and the antioxidant DTT did not affect their developmental competence.

  19. Effect of organic residues addition on the technological properties of clay bricks.

    PubMed

    Demir, Ismail

    2008-01-01

    The objective of this study is to investigate the utilization potential of several organic residues in clay bricks. Sawdust, tobacco residues, and grass are widespread by-products of industrial and agricultural processes in Turkey. These residue materials have long cellulose fibres. Sawdust and tobacco residues generally are used as fuel, and the grass is utilized for agricultural purposes. The insulation capacity of brick increases with the increasing porosity of the clay body. Combustible, organic types of pore-forming additives are most frequently used for this purpose. For this reason, increasing amounts of organic residues (0%, 2.5%, 5% and 10% in wt.) were mixed with raw brick-clay. All samples were fired at 900 degrees C. Effects on shaping, plasticity, density, and mechanical properties were investigated. The organic residue additions were found to be effective for pore-forming in the clay body with the clay maintaining acceptable mechanical properties. It was observed that the fibrous nature of the residues did not create extrusion problems. However, higher residue addition required a higher water content to ensure the right plasticity. As a result, sawdust, tobacco residues, and grass can be utilized in an environmentally safe way as organic pore-forming agents in brick-clay.

  20. Effect of medium additives during liquid storage on developmental competence of in vitro matured bovine oocytes

    PubMed Central

    Suttirojpattana, Tayita; Matoba, Satoko; Parnpai, Rangsun; Nagai, Takashi; Geshi, Masaya

    2016-01-01

    Abstract Our aim was to improve the developmental competence of bovine oocytes during their liquid storage by using additives. In vitro matured oocytes were stored for 20 h at 25°C in HEPES buffered TCM 199 medium (base medium). After storage, in vitro embryo development after in vitro fertilization was compared to those of non‐stored (control) ones. Addition of 10% (v/v) newborn calf serum or 10.27 mmol/L pyruvate alone to the base medium did not improve blastocyst formation rates in stored oocytes; however, their simultaneous addition significantly improved the rate compared with those stored in base medium (P < 0.05). Supplementation of the holding medium with dithiothreitol (DTT) at any concentrations did not improve embryo development from stored oocytes. Although supplementation with cyclosporine A (CsA) significantly reduced apoptosis and membrane damage rates during storage, it did not improve the developmental competence of oocytes. 1,2‐bis(2‐aminophenoxy) ethane N,N,N’,N’‐tetraacetic acid tetrakis‐acetoxymethyl ester and ruthenium red had no effect on oocyte apoptotic rates. Blastocyst formation rates in all stored groups remained significantly lower than that of the control. In conclusion, pyruvate and serum had a synergic effect to moderate the reduction of oocyte quality during storage, whereas mitochondrial membrane pore inhibitor CsA and the antioxidant DTT did not affect their developmental competence. PMID:27169667

  1. Effect of the La alloying addition on the antibacterial capability of 316L stainless steel.

    PubMed

    Yuan, J P; Li, W; Wang, C

    2013-01-01

    316L stainless steel is widely used for fashion jewelry but it can carry a large number of bacteria and cause the potential risk of infection since it has no antimicrobial ability. In this paper, La is used as an alloying addition. The antibacterial capability, corrosion resistance and processability of the La-modified 316L are investigated by microscopic observation, thin-film adhering quantitative bacteriostasis, electrochemical measurement and mechanical test. The investigations reveal that the La-containing 316L exhibits the Hormesis effect against Staphylococcus aureus ATCC 25923 and Escherichia coli DH5α, 0.05 wt.% La stimulates their growth, as La increases, the modified 316L exhibits the improved antibacterial effect. The more amount of La is added, the better antibacterial ability is achieved, and 0.42 wt.% La shows excellent antibacterial efficacy. No more than 0.11 wt.% La addition improves slightly the corrosion resistance in artificial sweat and has no observable impact on the processability of 316L, while a larger La content degrades them. Therefore, the addition of La alone in 316L is difficult to obtain the optimal combination of corrosion resistance, antibacterial capability and processability. In spite of that, 0.15 wt.% La around is inferred to be the trade-off for the best overall performance.

  2. The effects of stream bank vegetation on the flow characteristics and turbulent flow field of the main channel.

    NASA Astrophysics Data System (ADS)

    Valyrakis, M.; Yagci, O.; McGann, N. J.; Turker, U.

    2014-12-01

    Over the last two decades, the role of vegetation in the environmental and ecological restoration of surface water bodies has received much attention. Numerous studies have investigated the effects of vegetation on flow velocity at various locations ranging from the floodplain, river-bank and main channel. There is a general agreement amongst such studies, that the presence of vegetation may cause a decrease in flow velocity locally, followed by increased flows laterally, in non-vegetated regions. This experimental study attempts to present the findings of an elaborate set of flow measurements that aim at quantifying changes to the flow field at the main channel, at the bank inside the vegetated region and at their interface, for increasing vegetation density. To this goal an inclined section is constructed with acrylic panels sloping at, in a 1.8m wide re-circulating flume, to simulate the stream-bank. The main-channel bed comprises of coarse sand of 1.5mm nominal diameter, while 6mm diameter acrylic rods are used to simulate the vegetated river-bank. Ten velocity and turbulent intensity profiles are developed across the test cross-section, for each vegetation density, via acoustic Doppler velocimetry along a fine measurement grid. The experiments are run under uniform flow and stable bed conditions, for a range of six different vegetation densities changed by adding more vegetation elements in a staggered arrangement along the stream-bank. These detailed observations are further analyzed, with emphasis on the effects on the main channel. Measurements near the bed with implications for sediment transport are further discussed.

  3. Effect of the chlortetracycline addition method on methane production from the anaerobic digestion of swine wastewater.

    PubMed

    Huang, Lu; Wen, Xin; Wang, Yan; Zou, Yongde; Ma, Baohua; Liao, Xindi; Liang, Juanboo; Wu, Yinbao

    2014-10-01

    Effects of antibiotic residues on methane production in anaerobic digestion are commonly studied using the following two antibiotic addition methods: (1) adding manure from animals that consume a diet containing antibiotics, and (2) adding antibiotic-free animal manure spiked with antibiotics. This study used chlortetracycline (CTC) as a model antibiotic to examine the effects of the antibiotic addition method on methane production in anaerobic digestion under two different swine wastewater concentrations (0.55 and 0.22mg CTC/g dry manure). The results showed that CTC degradation rate in which manure was directly added at 0.55mg CTC/g (HSPIKE treatment) was lower than the control values and the rest of the treatment groups. Methane production from the HSPIKE treatment was reduced (p<0.05) by 12% during the whole experimental period and 15% during the first 7days. The treatments had no significant effect on the pH and chemical oxygen demand value of the digesters, and the total nitrogen of the 0.55mg CTC/kg manure collected from mediated swine was significantly higher than the other values. Therefore, different methane production under different antibiotic addition methods might be explained by the microbial activity and the concentrations of antibiotic intermediate products and metabolites. Because the primary entry route of veterinary antibiotics into an anaerobic digester is by contaminated animal manure, the most appropriate method for studying antibiotic residue effects on methane production may be using manure from animals that are given a particular antibiotic, rather than adding the antibiotic directly to the anaerobic digester.

  4. Effect of calcium chloride addition on ice cream structure and quality.

    PubMed

    Costa, F F; Resende, J V; Abreu, L R; Goff, H D

    2008-06-01

    The influence of calcium fortification by the addition of calcium chloride on quality parameters of ice cream based on physical properties was investigated, as was the effect of kappa-carrageenan at modifying the effects of this calcium fortification. Four ice cream mixes of conventional composition, with added kappa-carrageenan (0 or 0.025%) and added calcium chloride (0 or 4.4 g L(-1) = 40 mM of added Ca(2+)), were prepared. Modulated temperature-differential scanning calorimetry was used to investigate the effect of calcium chloride on the nucleation temperature, enthalpy of melting, and freezing point depression. The protein composition of 15.4% (wt/wt) reconstituted skim milk powder solutions with or without 4.4 g L(-1) added CaCl(2) and in the supernatant after ultracentrifugation was determined. Fat particle size distributions in ice cream were characterized by light scattering. Ice crystal sizes before and after temperature cycling were determined by cold-stage light microscopy. The results demonstrated that the addition of calcium chloride led to a substantial increase in ice crystal sizes and in fat partial coalescence, which were exacerbated by the addition of kappa-carrageenan. These results can be explained by the interaction between Ca(2+) ions and casein micelles, rather than any effects on freezing point depression. The calcium ions led to a more compact micelle, less serum beta-casein, and high fat destabilization, all of which would be expected to reduce macromolecular structure and volume occupancy in the unfrozen phase, which led to increased rates of ice recrystallization.

  5. Experimental study on agitated drying characteristics of sewage sludge under the effects of different additive agents.

    PubMed

    Deng, Wenyi; Su, Yaxin

    2014-07-01

    Drying experiments of dewatered sewage sludge (DSS) were conducted on a agitated paddle dryer, and the effects of additive agents, i.e., CaO, pulverized coal (PC), heavy oil (HO), and dried sludge ("DS" through back mixing) on the agitated drying characteristics of DSS were investigated. The results indicated that CaO can significantly increase the drying rate of DSS. The drying rate at CaO/DSS (mass ratio)=1/100 was 135% higher than that of CaO/DSS=0. Pulverized coal has no obvious effect on drying rate, but the increase of PC/DSS can promote breaking up of sludge lump. Heavy oil was found to be slightly effective in improving the drying rate of DSS in the examined experimental range of HO/DSS=0-1/20. It is also found that HO can reduce the torque of the dryer shaft, due to its lubrication effect. Back mixing of DS was found to be effective in alleviating the unfavorable effect of the lumpy phase by improving the mixing effect of the paddle dryer. There was a marked increase of drying rate with an increase of the DS/DSS in the experimental range of DS/DSS=0-1/3.

  6. [Effects of different perlite additions on physical and chemical properties of sewage sludge compost and growth of Tagetes patula].

    PubMed

    Hu, Yu-Tong; Shi, Lian-Hui; Liu, Deng-Min; Tong, Shao-Wei; Wei, Mei-Yan; Sun, Jie

    2014-07-01

    In order to resolve the problem of poor permeability of sewage sludge compost (SSC) which was used as the substitution of peat, perlite was used to regulate the permeability of the sewage. The pure SSC was used as control. The proportions of perlite in the mixtures with SSC were 20%, 40%, 60%, 80% and 100% (V/V), respectively. The effects of different perlite ratios on the physical and chemical properties and the growth of Tagetes patula were studied. The bulk density, water holding porosity and water holding porosity to aeration porosity decreased, but the total porosity and aeration porosity increased with the increasing addition of perlite to the SSC. For the chemical properties, the pH increased, and the EC and nutrient contents decreased with the increasing addition of perlite to the SSC. The aboveground biomass and flowers of T. patula were the highest in the 60% perlite treatment, and the lowest in the pure SSC treatment. The root morphology and activity were the best in the 40%, 60% and 80% perlite treatments. Aeration was the strongest factor to impact the maximum root length and average root diameter. Perlite promoted the growth of T. patula mainly through impacting the physical properties of the SSC. The addition of 60% perlite to the SSC could significantly improve the poor aeration and decrease the high salinity greatly in the SSC and regulate the growth of the root and aboveground of T. patula.

  7. The Brave New World of Personality Disorder-Trait Specified: Effects of Additional Definitions on Coverage, Prevalence, and Comorbidity

    PubMed Central

    Clark, Lee Anna; Vanderbleek, Emily N.; Shapiro, Jaime L.; Nuzum, Hallie; Allen, Xia; Daly, Elizabeth; Kingsbury, Thomas J.; Oiler, Morgan; Ro, Eunyoe

    2015-01-01

    The alternative dimensional model for personality disorder (PD) in DSM-5, Section III (DSM-5-III) includes two main criteria: (A) personality-functioning impairment, and (B) personality-trait pathology; provides specific functioning-and-trait criteria for six PD-type diagnoses; and introduces PD-trait specified (PD-TS), which requires meeting the general PD criteria and not meeting criteria for any specific PD type. We termed this Simple PD-TS and developed two additional definitions: Mixed PD-TS, meeting criteria for one or two PD types and having five or more additional pathological traits; and Complex PD-TS, meeting criteria for three or more PD types. In a mixed sample of 165 outpatients and 215 community adults screened to be at high-risk for PD, we investigated the effect of these additional definitions on prevalence, coverage, comorbidity, and within-diagnosis heterogeneity, and conclude that eliminating the PD-type diagnoses and thus having PD-TS as the only PD diagnosis would be both more parsimonious and more useful clinically. PMID:26097740

  8. Effect of Addition of Fentanyl to Xylocaine Hydrochloride in Brachial Plexus Block by Supraclavicular Approach

    PubMed Central

    Paluvadi, Venkata Raghavendra; Manne, Venkata Sesha Sai Krishna

    2017-01-01

    Aim: This study was designed to quantitatively compare the effects of 1.5% xylocaine with 1.5% xylocaine and fentanyl (1 μg/kg) mixture for supraclavicular brachial plexus block. Materials and Methods: Sixty patients between the age group of 20–60 and scheduled for upper limb surgery were divided into two groups (xylocaine group and xylocaine plus fentanyl group). After performing supraclavicular brachial plexus block, an assessment was made for onset of analgesia, duration and degree of analgesia, block intensity, and for any other side effects. Results: Mean duration of analgesia is Group I is 2.1 h and in Group II is 8.1 h; a four-fold increase in duration of analgesia. Conclusion: Addition of fentanyl to xylocaine for supraclavicular brachial plexus block has no significant effect on onset or quality of analgesia, but duration of analgesia is significantly prolonged. PMID:28298769

  9. Effects of maternally exposed food coloring additives on laryngeal histology in rats.

    PubMed

    Başak, Kayhan; Doguç, Duygu Kumbul; Aylak, Firdevs; Karadayi, Nimet; Gültekin, Fatih

    2014-01-01

    Experimental reports showed carcinogenic effects of artificial food colors and additives (AFCAs) on many organs, including the head and neck region. We aimed to investigate the effect of AFCAs on laryngeal histomorphology and immunohistochemical expression in maternally exposed rats. "No observable adverse effect levels" of commonly used AFCAs as a mixture were given to female rats before and during gestation. Histopathological and immunohistochemical findings were evaluated in their offspring. Significant decreasing in goblet cell count and cilia loss were observed with AFCAs in maternally exposed rats (p<0.05). Immunohistochemically, the Ki67 index was significantly increased and villin expression was significantly reduced in laryngeal epithelium in the study group (p<0.05), whereas expression of cyclooxygenase type 2, Muc-2, Muc-5AC, p53, and epidermal growth factor receptors did not differ between the groups. This study demonstrated that maternal exposure of AFCAs plays a role in the mucosal defense system and possibly in carcinogenesis.

  10. Effect of metal oxides addition on the superconducting properties of YBaCuO.

    PubMed

    Lee, Sang-Heon; Choi, Yong

    2011-07-01

    The superconducting properties of YBCO superconductor with ZrO2 addition prepared by different contents were prepared by a unique method so called thermal pyrolysis process to study the effect of the zirconium oxide on the electromagnetic properties and superconducting mechanism of the superconductor. The critical temperature of YBCO superconductor was not predominately dependent upon the zirconium oxide. The maximum magnetism was observed by adding 2% zirconium oxide. The addition of zirconium oxide forming a pinning center of magnetic flux due to ZrO2 phase which was related to the change of electromagnetic properties of the YBCO superconductor. The result indicates that magnetization is proportional to the number of magnetic flux lines passing through the sample. The added ZrO2 appear to contribute the increasing Vickers hardness.

  11. Effect of Pd Additions on the Invariant Reactions in the Ag-CuOx System

    SciTech Connect

    Darsell, Jens T.; Weil, K. Scott

    2006-02-01

    Palladium was added as a ternary component to a series of copper oxide-silver alloys in an effort increase the use temperature of these materials for potential ceramic brazing applications. Phase equilibria at low palladium and copper oxide concentrations in the Pd-CuOx-Ag system were determined experimentally using differential scanning calorimetry, microstructural analysis, and X-ray diffraction. Small additions of palladium were generally found to increase the temperature of the eutectic reaction present in the pseudobinary system, but have little effect on a higher temperature monotectic reaction. However once enough palladium was added (~5 mol%) to increase the new eutectic temperature to that of the original pseudobinary monotectic reaction, the pseudoternary monotectic temperature correspondingly began to move upward as well. The addition of palladium also forced the eutectic point to slightly lower silver concentrations, again causing a convergence with the former monotectic line.

  12. Noiseless intensity amplification of repetitive signals by coherent addition using the temporal Talbot effect

    PubMed Central

    Maram, Reza; Van Howe, James; Li, Ming; Azaña, José

    2014-01-01

    Amplification of signal intensity is essential for initiating physical processes, diagnostics, sensing, communications and measurement. During traditional amplification, the signal is amplified by multiplying the signal carriers through an active gain process, requiring the use of an external power source. In addition, the signal is degraded by noise and distortions that typically accompany active gain processes. We show noiseless intensity amplification of repetitive optical pulse waveforms with gain from 2 to ~20 without using active gain. The proposed method uses a dispersion-induced temporal self-imaging (Talbot) effect to redistribute and coherently accumulate energy of the original repetitive waveforms into fewer replica waveforms. In addition, we show how our passive amplifier performs a real-time average of the wave-train to reduce its original noise fluctuation, as well as enhances the extinction ratio of pulses to stand above the noise floor. Our technique is applicable to repetitive waveforms in any spectral region or wave system. PMID:25319207

  13. Effects on stress rupture life and tensile strength of tin additions to Inconel 718

    NASA Technical Reports Server (NTRS)

    Dreshfield, R. L.; Johnson, W.

    1982-01-01

    Because Inconel 718 represents a major use of columbium and a large potential source of columbium for aerospace alloys could be that of columbium derived from tin slags, the effects of tin additions to Inconel 718 at levels which might be typical of or exceed those anticipated if tin slag derived columbium were used as a melting stock were investigated. Tin was added to 15 pound Inconel 718 heats at levels varying from none added to approximately 10,000 ppm (1 wt%). Limited 1200 F stress rupture testing was performed at stresses from 68,000 to 115,000 psi and a few tensile tests were performed at room temperature, 800 and 1200 F. Additions of tin in excess of 800 ppm were detrimental to ductility and stress rupture life.

  14. Effect of additions of aluminosilicate and silicate materials on the softening temperature of chromite ore

    NASA Astrophysics Data System (ADS)

    Zhdanov, A. V.; Nurmaganbetova, B. N.; Pavlov, V. A.

    2015-07-01

    The temperatures of the beginning and end of softening and the temperature range of softening of the fines of the rich chromite ore of the Donskoy Ore Mining & Processing Plant in Kazakhstan are experimentally determined. The following natural and technical silica-containing materials, which are considered as fluxing additions to decrease the melting temperature of the chromite ore, are investigated: aluminosilicate clays, microsilica, and quartzite of various fractions. The effect of additions of the natural and technical silica-containing materials on the temperatures of the beginning and end of softening and the temperature range of softening of the chromite ore of DODPE is analyzed. The influences of various materials and their fraction compositions on the temperature of softening of the chromite ores are compared.

  15. Effect of PMMA filler particles addition on the physical properties of resin composite.

    PubMed

    Kondo, Yoshiko; Takagaki, Tomohiro; Okuda, Makoto; Ikeda, Masaomi; Kadoma, Yoshinori; Yamauchi, Junichi; Okada, Koichi; Sadr, Alireza; Nikaido, Toru; Tagami, Junji

    2010-10-01

    The aim of this study was to evaluate the effect of additional polymethyl methacrylate (PMMA) fillers on the physical properties of experimental resin composites. PMMA particles (d=30 µm) were added to an experimental methacrylate-based resin composite in five concentrations of 0, 2.0, 4.8, 9.1, and 23.1 wt%. Properties such as contact angle, water sorption and compressive strength were measured and the fractured specimens were observed with a scanning electron microscope. The results showed that a small amount (2 wt%) of additional PMMA fillers inhibited the crack propagation and enhanced compressive strengths of the resin composites, without a significant change in water contact angle of surface or increased water sorption. However, in higher portions, the mechanical properties were not improved as a debonding at the interface between untreated fillers and the matrix, or failure within the organic filler could reduce the compressive yield strength of the composite.

  16. Inhaled diesel emissions generated with cerium oxide nanoparticle fuel additive induce adverse pulmonary and systemic effects.

    PubMed

    Snow, Samantha J; McGee, John; Miller, Desinia B; Bass, Virginia; Schladweiler, Mette C; Thomas, Ronald F; Krantz, Todd; King, Charly; Ledbetter, Allen D; Richards, Judy; Weinstein, Jason P; Conner, Teri; Willis, Robert; Linak, William P; Nash, David; Wood, Charles E; Elmore, Susan A; Morrison, James P; Johnson, Crystal L; Gilmour, Matthew Ian; Kodavanti, Urmila P

    2014-12-01

    Diesel exhaust (DE) exposure induces adverse cardiopulmonary effects. Cerium oxide nanoparticles added to diesel fuel (DECe) increases fuel burning efficiency but leads to altered emission characteristics and potentially altered health effects. Here, we evaluated whether DECe results in greater adverse pulmonary effects compared with DE. Male Sprague Dawley rats were exposed to filtered air, DE, or DECe for 5 h/day for 2 days. N-acetyl glucosaminidase activity was increased in bronchial alveolar lavage fluid (BALF) of rats exposed to DECe but not DE. There were also marginal but insignificant increases in several other lung injury biomarkers in both exposure groups (DECe > DE for all). To further characterize DECe toxicity, rats in a second study were exposed to filtered air or DECe for 5 h/day for 2 days or 4 weeks. Tissue analysis indicated a concentration- and time-dependent accumulation of lung and liver cerium followed by a delayed clearance. The gas-phase and high concentration of DECe increased lung inflammation at the 2-day time point, indicating that gas-phase components, in addition to particles, contribute to pulmonary toxicity. This effect was reduced at 4 weeks except for a sustained increase in BALF γ-glutamyl transferase activity. Histopathology and transmission electron microscopy revealed increased alveolar septa thickness due to edema and increased numbers of pigmented macrophages after DECe exposure. Collectively, these findings indicate that DECe induces more adverse pulmonary effects on a mass basis than DE. In addition, lung accumulation of cerium, systemic translocation to the liver, and delayed clearance are added concerns to existing health effects of DECe.

  17. Inhaled Diesel Emissions Generated with Cerium Oxide Nanoparticle Fuel Additive Induce Adverse Pulmonary and Systemic Effects

    PubMed Central

    Snow, Samantha J.; McGee, John; Miller, Desinia B.; Bass, Virginia; Schladweiler, Mette C.; Thomas, Ronald F.; Krantz, Todd; King, Charly; Ledbetter, Allen D.; Richards, Judy; Weinstein, Jason P.; Conner, Teri; Willis, Robert; Linak, William P.; Nash, David; Wood, Charles E.; Elmore, Susan A.; Morrison, James P.; Johnson, Crystal L.; Gilmour, Matthew Ian; Kodavanti, Urmila P.

    2014-01-01

    Diesel exhaust (DE) exposure induces adverse cardiopulmonary effects. Cerium oxide nanoparticles added to diesel fuel (DECe) increases fuel burning efficiency but leads to altered emission characteristics and potentially altered health effects. Here, we evaluated whether DECe results in greater adverse pulmonary effects compared with DE. Male Sprague Dawley rats were exposed to filtered air, DE, or DECe for 5 h/day for 2 days. N-acetyl glucosaminidase activity was increased in bronchial alveolar lavage fluid (BALF) of rats exposed to DECe but not DE. There were also marginal but insignificant increases in several other lung injury biomarkers in both exposure groups (DECe > DE for all). To further characterize DECe toxicity, rats in a second study were exposed to filtered air or DECe for 5 h/day for 2 days or 4 weeks. Tissue analysis indicated a concentration- and time-dependent accumulation of lung and liver cerium followed by a delayed clearance. The gas-phase and high concentration of DECe increased lung inflammation at the 2-day time point, indicating that gas-phase components, in addition to particles, contribute to pulmonary toxicity. This effect was reduced at 4 weeks except for a sustained increase in BALF γ-glutamyl transferase activity. Histopathology and transmission electron microscopy revealed increased alveolar septa thickness due to edema and increased numbers of pigmented macrophages after DECe exposure. Collectively, these findings indicate that DECe induces more adverse pulmonary effects on a mass basis than DE. In addition, lung accumulation of cerium, systemic translocation to the liver, and delayed clearance are added concerns to existing health effects of DECe. PMID:25239632

  18. Additive effects of physical stress and herbivores on intertidal seaweed biodiversity.

    PubMed

    Williams, Susan L; Bracken, Matthew E S; Jones, Emily

    2013-05-01

    Patterns in rocky intertidal seaweed biodiversity influence the resilience and functioning of these important primary producer communities. In turn, seaweed biodiversity patterns are the result of many ecological factors. We determined the influences of thermal and desiccation stress, herbivory, and nutrients on seaweed biodiversity on a northern California rocky shoreline. In a fully crossed design at two tidal heights at wave-protected and exposed sites, we deployed screens to reduce stress, removed herbivores, and added nutrients for 18 months. The treatments reduced temperature, increased relative humidity, decreased herbivore abundances, and increased nitrogen in both seawater and seaweeds. Seaweed abundance and biodiversity (cover, biomass, species richness, diversity, evenness, and community composition) were influenced by tidal height, physical stress, and herbivores. Wave exposure affected all response variables except biomass and evenness. Stress and herbivores had independent additive effects on seaweed abundance and diversity. Physical stress did not make the community as a whole more susceptible to herbivores, and screens had overarching positive effects on seaweed biodiversity even though they also had positive effects on herbivore abundance. Nutrients had virtually no effect on seaweed biodiversity, and we observed no bottom-up effects of nutrient addition on herbivore density or biomass. Small green algae and diatoms were important contributors to overall algal cover and to changes in composition across treatments, but larger macroalgae dominated the species richness response. The striking absence of interactions between stress and herbivory highlights how seaweed communities can respond independently to important drivers of biodiversity. Thus, nonadditive, potentially synergistic effects do not necessarily complicate the understanding of how seaweed biodiversity responds to environmental change.

  19. Effect of ethanol addition on soot precursors emissions during benzene oxidation in a jet-stirred reactor.

    PubMed

    Rezgui, Yacine; Guemini, Miloud

    2014-05-01

    A constant volume reactor model (PSR) was used to investigate the effect of ethanol addition on the formation of some pollutants during benzene oxidation in a jet-stirred reactor. The blended fuels were formed by incrementally adding 4% wt of oxygen (ethanol) to the neat benzene fuel and by keeping the inert mole fraction (nitrogen) and the equivalence ratio constants. The main objective of this work was to obtain fundamental understanding of the mechanisms through which the oxygenate compound affects soot precursor amounts. The modeling results showed that C2H2, C5H5, and C3H3 mole fractions decreased upon increasing the ethanol percentage in the fuel mixture.

  20. Effect of Exogenous Phytase Addition on Soil Phosphatase Activities: a Fluorescence Spectroscopy Study.

    PubMed

    Yang, Xiao-zhu; Chen, Zhen-hua; Zhang, Yu-lan; Chen, Li-jun

    2015-05-01

    The utilization of organic phosphorus (P) has directly or indirectly improved after exogenous phytase was added to soil. However, the mechanism by which exogenous phytase affected the soil phosphatases (phosphomonoesterase and phosphodiesterase) activities was not clear. The present work was aimed to study red soil, brown soil and cinnamon soil phosphomonoesterase (acid and alkaline) (AcP and AlP) and phosphodiesterase (PD) activities responding to the addition of exogenous phytase (1 g phytase/50 g air dry soil sample) based on the measurements performed via a fluorescence detection method combined with 96 microplates using a TECAN Infinite 200 Multi-Mode Microplate Reader. The results indicated that the acid phosphomonoesterase activity was significantly enhanced in red soil (p≤0. 01), while it was significantly reduced in cinnamon soil; alkaline phosphomonoesterase activity was significantly enhanced in cinnamon soil (p≤ 0. 01), while it was significantly reduced in red soil; phosphodiesterase activity was increased in three soils but it was significantly increased in brown soil (p≤0. 01) after the addition of exogenous phytase. The activities still remained strong after eight days in different soils, which indicated that exogenous phytase addition could be enhance soil phosphatases activities effectively. This effect was not only related to soil properties, such as pH and phosphorus forms, but might also be related to the excreted enzyme amount of the stimulating microorganism. Using fluorescence spectroscopy to study exogenous phytase addition influence on soil phosphatase activities was the first time at home and abroad. Compared with the conventional spectrophotometric method, the fluorescence microplate method is an accurate, fast and simple to use method to determine the relationships among the soil phosphatases activities.

  1. Anaerobic digestion of Jatropha curcas L. press cake and effects of an iron-additive.

    PubMed

    Schmidt, Thomas

    2011-11-01

    Oil production from Jatropha curcas L. seeds generates large amounts of Jatropha press cake (JPC) which can be utilized as a substrate for biogas production. The objective of this work was to investigate anaerobic mono-digestion of JPC and the effects of an iron additive (IA) on gas quality and process stability during the increase of the organic loading rate (OLR). With the increase of the OLR from 1.3 to 3.2 g(VS) L(-1) day(-1), the biogas yield in the reference reactor (RR) without IA decreased from 512 to 194 L(N) kg(VS) (-1) and the CH₄ concentration decreased from 69.3 to 44.4%. In the iron additive reactor (IAR), the biogas yield decreased from 530 to 462 L(N) kg(VS) (-1) and the CH₄ concentration decreased from 69.4 to 61.1%. The H₂S concentration in the biogas was reduced by addition of the IA to values below 258 ppm in the IAR while H₂S concentration in the RR increased and exceeded the detection limit of 5000 ppm. The acid capacity (AC) in the RR increased to more than 20 g L(-1), indicating an accumulation of organic acids caused by process instability. AC values in the IAR remained stable at values below 5 g L(-1). The results demonstrate that JPC can be used as sole substrate for anaerobic digestion up to an OLR of 2.4 g(VS) l(-1) day(-1). The addition of IA has effectively decreased the H(2)S content in the biogas and has improved the stability of the anaerobic process and the biogas quality.

  2. Thermodynamic Effect of Platinum Addition to beta-NiAl: An Initial Investigation

    NASA Technical Reports Server (NTRS)

    2005-01-01

    An initial investigation was conducted to determine the effect of platinum addition on the activities of aluminum and nickel in beta-NiAl(Pt) over the temperature range 1354 to 1692 K. These measurements were made with a multiple effusion-cell configured mass spectrometer (multi-cell KEMS). The results of this study show that Pt additions act to decreased alpha(Al) and increased the alpha(Ni) in beta-NiAl(Pt) for constant X(sub Ni)/X(sub Al) approx. = 1.13, while at constant X(sub Al) the affect of Pt on Al is greatly reduced. The measured partial enthalpies of mixing indicate Al-atoms have a strong self interaction while Ni- and Pt-atoms in have similar interactions with Al-atoms. Conversely the binding of Ni-atoms in beta-NiAl decreases with Pt addition independent of Al concentration. These initial results prove the technique can be applied to the Ni-Al-Pt system but more activity measurements are required to fully understand the thermodynamics of this system and how Pt additions improved the scaling behavior of nickel-based superalloys. In addition, with the choice of a suitable oxide material for the effusion-cell, the "closed" isothermal nature of the effusion-cell allows the direct investigation of an alloy-oxide equilibrium which resembles the "local-equilibrium" description of the metal-scale interface observed during high temperature oxidation. It is proposed that with an Al(l) + Al2O3(s) experimental reference state together with the route measurement of the relative partial-pressures of Al(g) and Al2O(g) allows the activities of O and Al2O3 to be determined along with the activities of Ni and Al. These measurements provide a direct method of investigating the thermodynamics of the metal-scale interface of a TGO-scale.

  3. THE EFFECTS OF ROTATION ON THE MAIN-SEQUENCE TURNOFF OF INTERMEDIATE-AGE MASSIVE STAR CLUSTERS

    SciTech Connect

    Yang, Wuming; Bi, Shaolan; Liu, Zhie; Meng, Xiangcun E-mail: yangwuming@ynao.ac.cn

    2013-10-20

    The double or extended main-sequence turnoffs (MSTOs) in the color-magnitude diagram (CMD) of intermediate-age massive star clusters in the Large Magellanic Cloud are generally interpreted as age spreads of a few hundred Myr. However, such age spreads do not exist in younger clusters (i.e., 40-300 Myr), which challenges this interpretation. The effects of rotation on the MSTOs of star clusters have been studied in previous works, but the results obtained are conflicting. Compared with previous works, we consider the effects of rotation on the main-sequence lifetime of stars. Our calculations show that rotating models have a fainter and redder MSTO with respect to non-rotating counterparts with ages between about 0.8 and 2.2 Gyr, but have a brighter and bluer MSTO when age is larger than 2.4 Gyr. The spread of the MSTO caused by a typical rotation rate is equivalent to the effect of an age spread of about 200 Myr. Rotation could lead to the double or extended MSTOs in the CMD of the star clusters with ages between about 0.8 and 2.2 Gyr. However, the extension is not significant, and it does not even exist in younger clusters. If the efficiency of the mixing were high enough, the effects of the mixing would counteract the effect of the centrifugal support in the late stage of evolution, and the rotationally induced extension would disappear in the old intermediate-age star clusters, but younger clusters would have an extended MSTO. Moreover, the effects of rotation might aid in understanding the formation of some 'multiple populations' in globular clusters.

  4. The effect of additional etching and curing mechanism of composite resin on the dentin bond strength

    PubMed Central

    Lee, In-Su; Son, Sung-Ae; Hur, Bock; Kwon, Yong-Hoon

    2013-01-01

    PURPOSE The aim of this study was to evaluate the effects of additional acid etching and curing mechanism (light-curing or self-curing) of a composite resin on the dentin bond strength and compatibility of one-step self-etching adhesives. MATERIALS AND METHODS Sixteen human permanent molars were randomly divided into eight groups according to the adhesives used (All-Bond Universal: ABU, Clearfil S3 Bond: CS3), additional acid etching (additional acid etching performed: EO, no additional acid etching performed: EX), and composite resins (Filtek Z-250: Z250, Clearfil FII New Bond: CFNB). Group 1: ABU-EO-Z250, Group 2: ABU-EO-CFNB, Group 3: ABU-EX-Z250, Group 4: ABU-EX-CFNB, Group 5: CS3-EO-Z250, Group 6: CS3-EO-CFNB, Group 7: CS3-EX-Z250, Group 8: CS3-EX-CFNB. After bonding procedures, composite resins were built up on dentin surfaces. After 24-hour water storage, the teeth were sectioned to make 10 specimens for each group. The microtensile bond strength test was performed using a microtensile testing machine. The failure mode of the fractured specimens was examined by means of an optical microscope at ×20 magnification. The data was analyzed using a one-way ANOVA and Scheffe's post-hoc test (α=.05). RESULTS Additional etching groups showed significantly higher values than the no additional etching group when using All-Bond Universal. The light-cured composite resin groups showed significantly higher values than the self-cured composite resin groups in the Clearfil S3 Bond. CONCLUSION The additional acid etching is beneficial for the dentin bond strength when using low acidic one-step self-etch adhesives, and low acidic one-step self-etch adhesives are compatible with self-cured composite resin. The acidity of the one-step self-etch adhesives is an influencing factor in terms of the dentin bonding strength and incompatibility with a self-cured composite resin. PMID:24353889

  5. Toward a mechanistic understanding of the effect of biochar addition on soil water retention

    NASA Astrophysics Data System (ADS)

    Yi, S.; Chang, N.; Guo, M.; Imhoff, P. T.

    2014-12-01

    Biochar (BC) is a carbon-rich product produced by thermal degradation of biomass in an oxygen-free environment, whose application to sediment is said to improve water retention. However, BC produced from different feedstocks and pyrolyzed at different temperatures have distinct properties, which may alter water retention in ways difficult to predict a priori. Our goal is to develop a mechanistic understanding of BC addition on water retention by examining the impact of BC from two feedstocks, poultry litter (PL) and hardwood (HW), on the soil-water retention curves (SWRC) of a uniform sand and a sandy loam (SL). For experiments with sand, BC and sand were sieved to the same particle size (~ 0.547 mm) to minimize effects of BC addition on particle size distribution. Experiments with SL contained the same sieved BC. PL and HW bicohars were added at 2 and 7% (w/w), and water retention was measured from 0 to -4.38 × 106 cm-H2O. Both BCs increased porosities for sand and SL, up to 39 and 13% for sand and SL, respectively, with 7% HW BC addition. The primary cause for these increases was the internal porosity of BC particles. While the matric potential for air-entry was unchanged with BC addition, BC amendment increased water retention for sand and SL in the capillary region (0 to -15,000 cm-H2O) by an average of 26 and 33 % for 7% PL and HW BC in sand, respectively, but only 7 and 14 % for 7% PL and HW BC in SL. The most dramatic influence of BC amendment on water retention occurred in the adsorption region (< -15,000 cm-H2O), where water retention increased by a factor of 11 and 22 for 7% PL and HW BC in sand, respectively, but by 140 and 190 % for 7% PL and HW BC in SL, respectively. The impact of BC on water retention in these sediments is explained primarily by the additional surface area and internal porosity of PL and HW BC particles. van Genuchten (VG) models were fitted to the water retention data. For SL where the impact of BC addition on water retention was

  6. Additive effects of vertebrate predators on insects in a Puerto Rican coffee plantation

    USGS Publications Warehouse

    Borkhataria, R.R.; Collazo, J.A.; Groom, M.J.

    2006-01-01

    A variety of studies have established the value of shaded coffee plantations as habitat for birds. While the value of birds as biological controls in coffee has received some attention, the interactions between birds and other predators of insects have not been tested. We used exclosures to examine the effects of vertebrate predators on the arthropods associated with coffee, in particular the coffee leafminer (Leucoptera coffeella) and the flatid planthopper Petrusa epilepsis, in a shaded coffee plantation in Puerto Rico. We used a 2 x 2 factorial design with four treatments: exclusion of birds, lizards, birds and lizards, and control (no exclusion). Abundance of insects >5 mm increased when birds or both birds and lizards were removed. Birds and lizards had an additive effect for insects <5 mm and for all insects combined. Coffee leafminers showed a weak response to removal of predators while planthopper abundance increased significantly in the absence of avian predators. Arthropod predators and parasitoids did not differ significantly between treatments. Our findings suggest that vertebrate insectivores have an additive effect on insects in coffee and may help control abundances of some coffee pests. Equally important, we present evidence suggesting that they do not interfere with other known natural enemies of coffee pests. ?? 2006 by the Ecological Society of America.

  7. Strength in numbers: Combining neck vibration and prism adaptation produces additive therapeutic effects in unilateral neglect

    PubMed Central

    Saevarsson, Styrmir; Kristjánsson, Árni; Halsband, Ulrike

    2010-01-01

    Unilateral neglect is a multifaceted disorder. Many authors have, for this reason, speculated that the best treatment for neglect will involve combinations of different therapeutic techniques. Two well known interventions, neck vibration (NV) and prism adaptation (PA), have often been considered to be among the most effective treatments for neglect. Here, two experiments were performed to explore possible additive benefits when these interventions are used in combination to treat chronic neglect. Both experimental groups received NV for 20 minutes, while the second group received simultaneous PA. The effects of treatment were measured with a time-restricted and feedback-based visual search task, which has previously been found to abolish the beneficial effects of PA, and with standard neglect tests. Baseline and intervention measures were performed on separate days. Findings for both groups indicated improved visual search following intervention, but the patients that underwent the combined intervention (NVPA) showed clear improvements on visual search based paper and pencil neglect tests unlike the NV-only group. Overall, our results suggest that PA strengthens the effects of NV and that feedback-based tasks do not abolish beneficial effects of PA, when NV is applied simultaneously. The results support the view that the most effective treatment for neglect will involve the combination of different treatments. PMID:20503132

  8. Effects of essential oil extracted from Nigella sativa (L.) seeds and its main components on human neutrophil elastase activity.

    PubMed

    Kacem, Rachid; Meraihi, Zahia

    2006-04-01

    The effects of essential oil extracted from Nigella sativa (L.) seeds and its main components on human neutrophil elastase (HNE) activity were investigated. Essential oil was extracted from N. sativa (L.) seeds using hydrodistillation. The yield was equal to 0.4%. Inhibition of HNE activity by essential oil was found to be dose dependent. The highest inhibitory concentration (HIC) of essential oil which caused total inhibition of HNE activity was 5.8 mg/ml. Microassays carried out to evaluate the inhibitory effect of major components of essential oil on HNE activity revealed that carvacrol (5-isopropyl-2-methylphenol) showed marked HNE inhibitory activity with a very low IC(50) value (12 microM). Based on these results, the inhibitory effects of essential oil on HNE activity are due to the presence of bioactive molecules, mainly carvacrol this compound is an inhibitor of HNE and could be considered as a natural antielastase agent and possible candidate for phytotherapy in the treatment of injuries that appear in some pathologic cases such as chronic obstructive pulmonary disease and emphysema.

  9. Additive anti-inflammatory effect of formoterol and budesonide on human lung fibroblasts

    PubMed Central

    Spoelstra, F; Postma, D; Hovenga, H; Noordhoek, J; Kauffman, H

    2002-01-01

    Background: It has been shown that treatment with a long acting ß2 agonist in addition to a glucocorticoid is beneficial in the treatment of asthma. In asthma inflammatory cells, particularly eosinophils, migrate into the pulmonary tissue and airway lumen by means of adhesion molecules expressed on resident tissue cells—that is, fibroblasts—and become activated by cytokines and adhesive interactions. A study was undertaken to determine whether an interaction exists between the long acting ß2 agonist formoterol and the glucocorticoid budesonide on inhibition of adhesion molecule expression, as well as chemo/cytokine production by human lung fibroblasts. Methods: Lung fibroblasts were preincubated with therapeutically relevant drug concentrations of 10-8 M to 10-10 M. Cells were stimulated with interleukin (IL)-1ß (1 or 10 U/ml) for 8 hours and supernatants were collected for measurement of GM-CSF and IL-8 concentrations. The cells were fixed and subjected to a cell surface ELISA technique to measure the expression of ICAM-1 and VCAM-1. Results: Formoterol exerted an additive effect on the inhibition of IL-1ß stimulated ICAM-1 and VCAM-1 upregulation and GM-CSF production by budesonide in concentrations of 10-9 M and above (p<0.05). IL-8 production was not influenced by formoterol. Conclusion: Formoterol exerts an additive effect on the anti-inflammatory properties of budesonide. In vitro data support the finding that the combination of budesonide and formoterol in asthma treatment strengthens the beneficial effect of either drug alone. PMID:11867828

  10. Effect of Crumb Rubber and Warm Mix Additives on Asphalt Aging, Rheological, and Failure Properties

    NASA Astrophysics Data System (ADS)

    Agrawal, Prashant

    Asphalt-rubber mixtures have been shown to have useful properties with respect to distresses observed in asphalt concrete pavements. The most notable change in properties is a large increase in viscosity and improved low-temperature cracking resistance. Warm mix additives can lower production and compaction temperatures. Lower temperatures reduce harmful emissions and lower energy consumption, and thus provide environmental benefits and cut costs. In this study, the effects of crumb rubber modification on various asphalts such as California Valley, Boscan, Alaska North Slope, Laguna and Cold Lake were also studied. The materials used for warm mix modification were obtained from various commercial sources. The RAF binder was produced by Imperial Oil in their Nanticoke, Ontario, refinery on Lake Erie. A second commercial PG 52-34 (hereafter denoted as NER) was obtained/sampled during the construction of a northern Ontario MTO contract. Some regular tests such as Dynamic Shear Rheometer (DSR) and Bending Beam Rheometer (BBR), Multiple Stress Creep Recovery (MSCR) and some modified new protocols such as the extended BBR test (LS-308) and the Double-Edge Notched Tension (DENT) test (LS-299) are used to study, the effect of warm mix and a host of other additives on rheological, aging and failure properties. A comparison in the properties of RAF and NER asphalts has also been made as RAF is good quality asphalt and NER is bad quality asphalt. From the studies the effect of additives on chemical and physical hardening tendencies was found to be significant. The asphalt samples tested in this study showed a range of tendencies for chemical and physical hardening.

  11. Cytotoxic Effects of Temozolomide and Radiation are Additive- and Schedule-Dependent

    SciTech Connect

    Chalmers, Anthony J.; Ruff, Elliot M.; Martindale, Christine; Lovegrove, Nadia; Short, Susan C.

    2009-12-01

    Purpose: Despite aggressive therapy comprising radical radiation and temozolomide (TMZ) chemotherapy, the prognosis for patients with glioblastoma multiforme (GBM) remains poor, particularly if tumors express O{sup 6}-methylguanine-DNA-methyltransferase (MGMT). The interactions between radiation and TMZ remain unclear and have important implications for scheduling and for developing strategies to improve outcomes. Methods and Materials: Factors determining the effects of combination therapy on clonogenic survival, cell-cycle checkpoint signaling and DNA repair were investigated in four human glioma cell lines (T98G, U373-MG, UVW, U87-MG). Results: Combining TMZ and radiation yielded additive cytotoxicity, but only when TMZ was delivered 72 h before radiation. Radiosensitization was not observed. TMZ induced G2/M cell-cycle arrest at 48-72 h, coincident with phosphorylation of Chk1 and Chk2. Additive G2/M arrest and Chk1/Chk2 phosphorylation was only observed when TMZ preceded radiation by 72 h. The ataxia-telangiectasia mutated (ATM) inhibitor KU-55933 increased radiation sensitivity and delayed repair of radiation-induced DNA breaks, but did not influence TMZ effects. The multiple kinase inhibitor caffeine enhanced the cytotoxicity of chemoradiation and exacerbated DNA damage. Conclusions: TMZ is not a radiosensitizing agent but yields additive cytotoxicity in combination with radiation. Our data indicate that TMZ treatment should commence at least 3 days before radiation to achieve maximum benefit. Activation of G2/M checkpoint signaling by TMZ and radiation has a cytoprotective effect that can be overcome by dual inhibition of ATM and ATR. More specific inhibition of checkpoint signaling will be required to increase treatment efficacy without exacerbating toxicity.

  12. Effect of Grape Pomace Powder Addition on TBARS and Color of Cooked Pork Sausages during Storage

    PubMed Central

    Ryu, Kyeong Seon; Shim, Kwan Seob; Shin, Daekeun

    2014-01-01

    To determine the effects of grape skin and seed pomace (GSP) additions on the lipid oxidation susceptibility and the color change of cooked pork sausages, the chemical characteristics of GSP itself and the addition for two different levels of GSP (0.5 and 1.0% GSP, respectively) to sausages were examined. Both the redness and blueness of the GSP were significantly reduced as the pH level was increased from 5 to 7, but a reverse result was determined in the color tint and yellowness (p<0.05). The GSP polyphenol and flavonoid contents were influenced by the percentages of methanol solvents, and more flavonoids were established when 100% of methanol was applied as a solvent to the GSP. But, similar results were not observed in the polyphenol of GSP. In cooked pork sausages, significant decreases in the lightness and redness were found in both the 0.5% and 1.0% of GSP sausages during the storage period (p<0.05). However, an incompatible effect was observed in terms of yellowness, which increased as compared to the control sausage after 6 days of storage. The 0.5% addition of GSP decreased the levels of TBARS (p<0.05), but the ability of GSP to minimize lipid oxidation was not dose dependent. Therefore, the results indicated that the GSP is an efficient suppressor of lipid oxidation and has latent effects as a natural antioxidant when 0.5% of GSP is added to the cooked pork sausages. PMID:26760939

  13. Effects of Additive on the Mechanical Properties of Bamboo/pbs Composites

    NASA Astrophysics Data System (ADS)

    Lee, Yeon-Hee; Yoon, Han-Ki; Takagi, Hitoshi; Ohkita, Kazuya

    Compared with general composites which are produced from fossil fuel, biodegradable resins have received considerable attention as an environment-friendly material. Bamboo fiber has relatively high strength compared with other natural fibers. Therefore, the focus of this study is to produce bamboo fiber reinforced Poly butylene succinate (PBS) composites by injection molding and to study the effects of additive on mechanical properties of this bamboo/PBS composite. The injection-molding is a highly productive fabrication technique. Bamboo/PBS composites were examined by flexural test and Vickers hardness. Also we examined fracture surface and microstructure of the bamboo/PBS composites by microscope.

  14. Effect of Oxygen addition on altitude blowout and relight of an experimental combustor segment

    NASA Technical Reports Server (NTRS)

    Norgren, C. T.; Ingebo, R. D.

    1974-01-01

    The effect of oxygen addition on the low pressure altitude blowout limits of an experimental combustor segment was investigated. Data were obtained for two inlet-air temperatures, two inlet-airflow rates, and a constant fuel-air ratio of 0.020 with Jet A fuel. It was shown that the pressure at blowout could be reduced to correspond to an increase in altitude of 4.6 kilometers with oxygen flow rates of 8 to 16 percent by weight of the total fuel flow.

  15. Thermodynamic network model for predicting effects of substrate addition and other perturbations on subsurface microbial communities

    SciTech Connect

    Jack Istok; Melora Park; James McKinley; Chongxuan Liu; Lee Krumholz; Anne Spain; Aaron Peacock; Brett Baldwin

    2007-04-19

    The overall goal of this project is to develop and test a thermodynamic network model for predicting the effects of substrate additions and environmental perturbations on microbial growth, community composition and system geochemistry. The hypothesis is that a thermodynamic analysis of the energy-yielding growth reactions performed by defined groups of microorganisms can be used to make quantitative and testable predictions of the change in microbial community composition that will occur when a substrate is added to the subsurface or when environmental conditions change.

  16. Effect of Zn additions on precipitation during aging of alloy 8090

    NASA Technical Reports Server (NTRS)

    Kilmer, R. J.; Stoner, G. E.

    1991-01-01

    Precipitation events have been observed by TEM under two different aging conditions in three 'stretched' alloys, whose compositions are encompassed by the 8090 composition window but contain Zn additions of up to 1.07 wt pct. DSC was also used to obtain deeper insight of the precipitation-event effects obtainable through Zn content variation; it was thereby revealed that Zn is incorporated into the delta-prime phase, perhaps stabilizing it. Coarse, Zn-containing precipitates can form on the boundaries and within the interiors of the grains, when the Zn content reaches the presently investigated maximum of 1.07 wt pct.

  17. Suppression of flow pulsation activity by relaxation process of additive effect on viscous media transport

    NASA Astrophysics Data System (ADS)

    Kharlamov, S.; Dedeyev, P.; Meucci, L.; Shenderova, I.; Manastirniy, A.; Usenko, M.

    2015-11-01

    The article presents the analysis of the processes occurring together with the turbulent transfer of impulse in mixture of hydrocarbon fluid and polymer solutions (anti-turbulent additives). The study evaluates complex shear flows by popular theoretical and practical methods. Understanding of hydrodynamic and dissipative effects of laminar-turbulent transition tightening and turbulence suppression is provided. The peculiarities of "thin" flow structure in pipeline zones with complex shape walls are evaluated. Recommendations to forecast the local flow parameters, calculation of hydraulic resistance are given.

  18. Effects of methanol-containing additive on emission characteristics from a heavy-duty diesel engine.

    PubMed

    Chao, M R; Lin, T C; Chao, H R; Chang, F H; Chen, C B

    2001-11-12

    This study was aimed to investigate the effect of methanol-containing additive (MCA) on the regulated emissions of hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NOx), particulate matter (PM), as well as the unregulated carbon dioxide (CO2) and polycyclic aromatic hydrocarbons (PAHs) from a diesel engine. The engine was tested on a series of diesel fuels blended with five additive levels (0, 5, 8, 10 and 15% of MCA by volume). Emissions tests were performed under both cold- and hot-start transient heavy-duty federal test procedure (HD-FTP) cycles and two selected steady-state modes. Results show that MCA addition slightly decreases PM emissions but generally increases both THC and CO emissions. Decrease in NOx emissions was found common in all MCA blends. As for unregulated emissions, CO2 emissions did not change significantly for all MCA blends, while vapor-phase and particle-associated PAHs emissions in high load and transient cycle tests were relatively low compared to the base diesel when either 5 or 8% MCA was used. This may be attributed to the lower PAHs levels in MCA blends. Finally, the particle-associated PAHs emissions also showed trends quite similar to that of the PM emissions in this study.

  19. Compensation and additivity of anthropogenic mortality: life-history effects and review of methods.

    PubMed

    Péron, Guillaume

    2013-03-01

    Demographic compensation, the increase in average individual performance following a perturbation that reduces population size, and, its opposite, demographic overadditivity (or superadditivity) are central processes in both population ecology and wildlife management. A continuum of population responses to changes in cause-specific mortality exists, of which additivity and complete compensation constitute particular points. The position of a population on that continuum influences its ability to sustain exploitation and predation. Here I describe a method for quantifying where a population is on the continuum. Based on variance-covariance formulae, I describe a simple metric for the rate of compensation-additivity. I synthesize the results from 10 wildlife capture-recapture monitoring programmes from the literature and online databases, reviewing current statistical methods and the treatment of common sources of bias. These results are used to test hypotheses regarding the effects of life-history strategy, population density, average cause-specific mortality and age class on the rate of compensation-additivity. This comparative analysis highlights that long-lived species compensate less than short-lived species and that populations below their carrying capacity compensate less than those above.

  20. Effect of Fruit Pomace Addition on Shortbread Cookies to Improve Their Physical and Nutritional Values.

    PubMed

    Tańska, Małgorzata; Roszkowska, Beata; Czaplicki, Sylwester; Borowska, Eulalia Julitta; Bojarska, Justyna; Dąbrowska, Aneta

    2016-09-01

    Fruit pomace remaining after juice extraction is still a source of bioactive compounds. Especially rich in these compounds is the pomace from blackcurrant fruit and from fruits of little-known horticultural plants, like: rowan, rosehip and elderberry. The addition of fruit pomace to bakery and confectionery products, especially to those made of white flour, may significantly enrich their composition with dietary fiber, vitamins and phenolic compounds. This study was aimed at determining the effect of 20 % addition of fruit pomace from rosehip, rowan, blackcurrant and elderberry on the properties of shortbread cookies. The pomace-containing cookies, compared to those without additives, were characterized by a darker color with a higher contribution of yellowness, and by higher hardness. The overall organoleptic assessment was comparable for all types of cookies, however the cookies with pomace were characterized by more perceptible taste and aroma, and were sourer. The extracts from pomace-supplemented cookies had a significantly stronger antioxidant capacity than that from the cookies without pomace, but they were ineffective in inhibiting lipid oxidation. The study showed that fruit pomace could improve the nutritional value of shortbread cookies. Furthermore, non-typical color of such a new product may be attractive to consumers.

  1. Effects of resource addition on recovery of production and plant functional composition in degraded semiarid grasslands.

    PubMed

    Chen, Qing; Hooper, David U; Li, Hui; Gong, Xiao Ying; Peng, Fei; Wang, Hong; Dittert, Klaus; Lin, Shan

    2017-02-28

    Degradation of semiarid ecosystems from overgrazing threatens a variety of ecosystem services. Rainfall and nitrogen commonly co-limit production in semiarid grassland ecosystems; however, few studies have reported how interactive effects of precipitation and nitrogen addition influence the recovery of grasslands degraded by overgrazing. We conducted a 6-year experiment manipulating precipitation (natural precipitation and simulated wet year precipitation) and nitrogen (0, 25 and 50 kg N ha(-1)) addition at two sites with different histories of livestock grazing (moderately and heavily grazed) in Inner Mongolian steppe. Our results suggest that recovery of plant community composition and recovery of production can be decoupled. Perennial grasses provide long-term stability of high-quality forage production in this system. Supplemental water combined with exclosures led, in the heavily grazed site, to the strongest recovery of perennial grasses, although widespread irrigation of rangeland is not a feasible management strategy in many semiarid and arid regions. N fertilization combined with exclosures, but without water addition, increased dominance of unpalatable annual species, which in turn retarded growth of perennial species and increased inter-annual variation in primary production at both sites. Alleviation of grazing pressure alone allowed recovery of desired perennial species via successional processes in the heavily grazed site. Our experiments suggest that recovery of primary production and desirable community composition are not necessarily correlated. The use of N fertilization for the management of overgrazed grassland needs careful and systematic evaluation, as it has potential to impede, rather than aid, recovery.

  2. Monitoring Residual Solvent Additives and Their Effects in Solution Processed Solar Cells

    NASA Astrophysics Data System (ADS)

    Fogel, Derek M.; Basham, James I.; Engmann, Sebastian; Pookpanratana, Sujitra J.; Bittle, Emily G.; Jurchescu, Oana D.; Gundlach, David J.

    2015-03-01

    High boiling point solvent additives are a widely adopted approach for increasing bulk heterojunction (BHJ) solar cell efficiency. However, experiments show residual solvent can persist for hours after film deposition, and certain common additives are unstable or reactive. We report here on the effects of residual 1,8-diiodooctane on the electrical performance of poly(3-hexylthiophene-2,5-diyl) (P3HT): phenyl-C71-butyric acid methyl ester (PC[71]BM) BHJ photovoltaic cells. We optimized our fabrication process for efficiency at an active layer thickness of 220 nm, and all devices were processed in parallel to minimize unintentional variations between test structures. The one variable in this study is the active layer post spin drying time. Immediately following the cathode deposition, we measured the current-voltage characteristics at one sun equivalent illumination intensity, and performed impedance spectroscopy to quantify charge density, lifetime, and recombination process. Spectroscopic ellipsometry, FTIR, and XPS are also used to monitor residual solvent and correlated with electrical performance. We find that residual additive degrades performance by increasing the series resistance and lowering efficiency, fill factor, and free carrier lifetime.

  3. Magnetic Force Microscopy Study of Zr2Co11 -Based Nanocrystalline Materials: Effect of Mo Addition

    DOE PAGES

    Yue, Lanping; Jin, Yunlong; Zhang, Wenyong; ...

    2015-01-01

    Tmore » he addition of Molybdenum was used to modify the nanostructure and enhance coercivity of rare-earth-free Zr2Co11-based nanocrystalline permanent magnets. he effect of Mo addition on magnetic domain structures of melt spun nanocrystalline Zr16Co84-xMox(x=0, 0.5, 1, 1.5, and 2.0) ribbons has been investigated. It was found that magnetic properties and local domain structures are strongly influenced by Mo doping. he coercivity of the samples increases with the increase in Mo content (x≤1.5). he maximum energy product(BH)maxincreases with increasingxfrom 0.5 MGOe forx=0to a maximum value of 4.2 MGOe forx=1.5. he smallest domain size with a relatively short magnetic correlation length of 128 nm and largest root-mean-square phase shiftΦrmsvalue of 0.66° are observed for thex=1.5. he optimal Mo addition promotes magnetic domain structure refinement and thus leads to a significant increase in coercivity and energy product in this sample.« less

  4. Effect of additives on the tensile performance and protein solubility of industrial oilseed residual based plastics.

    PubMed

    Newson, William R; Kuktaite, Ramune; Hedenqvist, Mikael S; Gällstedt, Mikael; Johansson, Eva

    2014-07-16

    Ten chemical additives were selected from the literature for their proposed modifying activity in protein-protein interactions. These consisted of acids, bases, reducing agents, and denaturants and were added to residual deoiled meals of Crambe abyssinica (crambe) and Brassica carinata (carinata) to modify the properties of plastics produced through hot compression molding at 130 °C. The films produced were examined for tensile properties, protein solubility, molecular weight distribution, and water absorption. Of the additives tested, NaOH had the greatest positive effect on tensile properties, with increases of 105% in maximum stress and 200% in strain at maximum stress for crambe and a 70% increase in strain at maximum stress for carinata. Stiffness was not increased by any of the applied additives. Changes in tensile strength and elongation for crambe and elongation for carinata were related to changes in protein solubility. Increased pH was the most successful in improving the protein aggregation and mechanical properties within the complex chemistry of residual oilseed meals.

  5. Effect of carbon nanotube addition on the wear behavior of basalt/epoxy woven composites.

    PubMed

    Kim, M T; Rhee, K Y; Lee, B H; Kim, C J

    2013-08-01

    The effect of acid-treated carbon nanotube (CNT) addition on the wear and dynamic mechanical thermal properties of basalt/epoxy woven composites was investigated in this study. Basalt/CNT/epoxy composites were fabricated by impregnating woven basalt fibers into epoxy resin mixed with 1 wt% CNTs which were acid-treated. Wear and DMA (dynamic mechanical analyzer) tests were performed on basalt/epoxy composites and basalt/CNT/epoxy composites. The results showed that the addition of the acid-treated CNTs improved the wear properties of basalt/epoxy woven composites. Specifically, the friction coefficient of the basalt/epoxy composite was stabilized in the range of 0.5-0.6 while it fell in the range of 0.3-0.4 for basalt/CNT/epoxy composites. The wear volume loss of the basalt/CNT/epoxy composites was approximately 68% lower than that of the basalt/epoxy composites. The results also showed that the glass transition temperature of basalt/CNT/epoxy composites was higher than that of basalt/epoxy composites. The improvement of wear properties of basalt/epoxy composites by the addition of acid-treated CNTs was caused by the homogeneous load transfer between basalt fibers and epoxy matrix due to the reinforcement of CNTs.

  6. Effect of additives on the properties of polyaniline nanofibers prepared by high gravity chemical oxidative polymerization.

    PubMed

    Zhao, Yibo; Arowo, Moses; Wu, Wei; Chen, Jianfeng

    2015-05-12

    Polyaniline (PANI) nanofibers with improved properties were prepared by high gravity chemical oxidative polymerization in a rotating packed bed with the assistance of p-aminodiphenylamine (AD) and p-phenylenediamine (AP). The effects of reactor type, additive dosage, reaction temperature, and high-gravity level on the properties of products were investigated in detail. Three conclusions were made: (1) a small amount of additive can significantly improve some properties of the nanofibers such as uniformity, specific surface area, and specific capacitance; (2) in order to obtain high-quality nanofibers, the high-gravity level should coordinate with the reaction rate; (3) the molecular weight and conductivity of PANI decrease with the increase of additive dosage. The products have larger specific surface areas of up to 73.9 and 68.4 m(2)/g and consequently improved specific capacitance of up to 527.5 and 552 F/g for the PANI nanofibers prepared with AD and AP, respectively. However, the specific surface area and specific capacitance of pure PANI are only 49.1 m(2)/g and 333.3 F/g, respectively. This research provides a simple, reliable, and scalable method to produce PANI nanofibers of high performances.

  7. Effects of protein and peptide addition on lipid oxidation in powder model system.

    PubMed

    Park, Eun Young; Murakami, Hiroshi; Mori, Tomohiko; Matsumura, Yasuki

    2005-01-12

    The effect of protein and peptide addition on the oxidation of eicosapentaenoic acid ethyl ester (EPE) encapsulated by maltodextrin (MD) was investigated. The encapsulated lipid (powder lipid) was prepared in two steps, i.e., mixing of EPE with MD solutions (+/- protein and peptides) to produce emulsions and freeze-drying of the resultant emulsions. EPE oxidation in MD powder progressed more rapidly in the humid state [relative humidity (RH) = 70%] than in the dry state (RH = 10%). The addition of soy protein, soy peptide, and gelatin peptides improved the oxidation stability of EPE encapsulated by MD, and the inhibition of lipid oxidation by the protein and the peptides was more dramatic in the humid state. Especially, the oxidation of EPE was almost perfectly suppressed when the lipid was encapsulated with MD + soy peptide during storage in the humid state for 7 days. Several physical properties such as the lipid particle size of the emulsions, the fraction of nonencapsulated lipids, scanning electron microscopy images of powder lipids, and the mobility of the MD matrix were investigated to find the modification of encapsulation behavior by the addition of the protein and peptides, but no significant change was observed. On the other hand, the protein and peptides exhibited a strong radical scavenging activity in the powder systems as well as in the solution systems. These results suggest that a chemical mechanism such as radical scavenging ability plays an important role in the suppression of EPE oxidation in MD powder by soy proteins, soy peptides, and gelatin peptides.

  8. The Effect of Manganese Additions on the Reactive Evaporation of Chromium in Ni-Cr Alloys

    SciTech Connect

    Holcomb, Gordon R.; Alman, David E.

    2004-10-20

    Chromium is used as an alloy addition in stainless steels and nickel-chromium alloys to form protective chromium oxide scales. Chromium oxide undergoes reactive evaporation in high temperature exposures in the presence of oxygen and/or water vapor. The deposition of gaseous chromium species onto solid oxide fuel cell electrodes can reduce the efficiency of the fuel cell. Manganese additions to the alloy can reduce the activity of chromium in the oxide, either from solid solution replacement of chromium with manganese (at low levels of manganese) or from the formation of manganese-chromium spinels (at high levels of manganese). This reduction in chromium activity leads to a predicted reduction in chromium evaporation by as much as a factor of 35 at 800 C and 55 at 700 C. The results of evaporation loss measurements on nickel-chromium-manganese alloys are compared with the predicted reduction. Quantifying the effects of manganese additions on chromium evaporation should aid alloy development of metallic interconnects and balance-of-plant alloys.

  9. Effect of lysine addition on growth of black iguana (Ctenosaura pectinata).

    PubMed

    Guzmán, Juan José Ortiz; Luis, Arcos-García José; Martínez, Germán D Mendoza; Pérez, Fernando Xicoténcatl Plata; Mascorro, Gisela Fuentes; Inzunza, Gabriela Ruelas

    2013-01-01

    The effects of the addition of lysine to commercial feed given to captive black iguana (Ctenosaura pectinata) were evaluated in terms of growth and feed digestibility. Twenty-eight-day-old black iguana with an initial weight of 5.5 ± 0.3 g were housed individually in cages measuring 45 × 45 × 45 cm. The experiment lasted 150 days. The ambient temperature ranged from 28 to 35°C with a relative humidity of 60 to 95%. Treatments consisted of the addition of different percentages of lysine to the feed (0.0, 0.1, 0.2, and 0.3%, dry matter [DM] base). There was a linear response (P < 0.01) in daily gain (68, 112, 118, and 151 mg/d) and daily intake (251, 289, 297, and 337 mg/d) for levels from 0 to 0.3%, respectively, as well in the growth in head size, snout-vent length, and total length. The digestibility of DM, neutral detergent fiber, and acid detergent fiber were reduced linearly (P < 0.01) as lysine levels increased. Intake and digestibility were negatively correlated (r = -0.74; P < 0.001). It is concluded that the addition of lysine to the black iguana diet in the first months of life is important to stimulate growth and intake.

  10. Renormalization and additional degrees of freedom within the chiral effective theory for spin-1 resonances

    SciTech Connect

    Kampf, Karol; Novotny, Jiri; Trnka, Jaroslav

    2010-06-01

    We study in detail various aspects of the renormalization of the spin-1 resonance propagator in the effective field theory framework. First, we briefly review the formalisms for the description of spin-1 resonances in the path integral formulation with the stress on the issue of propagating degrees of freedom. Then we calculate the one-loop 1{sup --} meson self-energy within the resonance chiral theory in the chiral limit using different methods for the description of spin-1 particles, namely, the Proca field, antisymmetric tensor field, and the first-order formalisms. We discuss in detail technical aspects of the renormalization procedure which are inherent to the power-counting nonrenormalizable theory and give a formal prescription for the organization of both the counterterms and one-particle irreducible graphs. We also construct the corresponding propagators and investigate their properties. We show that the additional poles corresponding to the additional one-particle states are generated by loop corrections, some of which are negative norm ghosts or tachyons. We count the number of such additional poles and briefly discuss their physical meaning.

  11. Oil-Soluble Polymer Brush Grafted Nanoparticles as Effective Lubricant Additives for Friction and Wear Reduction

    SciTech Connect

    Wright, Roger A. E.; Wang, Kewei; Qu, Jun; Zhao, Bin

    2016-06-06

    Developments of high performance lubricants are driven by increasingly growing industrial demands and environmental concerns. We demonstrate oil-soluble polymer brush-grafted inorganic nanoparticles (hairy NPs) as highly effective lubricant additives for friction and wear reduction. A series of oil-miscible poly(lauryl methacrylate) brush-grafted silica and titania NPs were synthesized by surface-initiated atom transfer radical polymerization. Moreover, these hairy NPs showed exceptional stability in poly(alphaolefin) (PAO) base oil; no change in transparency was observed after being kept at -20, 22, and 100°C for ≥55 days. High-contact stress ball-on-flat reciprocating sliding tribological tests at 100°C showed that addition of 1 wt% of hairy NPs into PAO led to significant reductions in coefficient of friction (up to ≈40%) and wear volume (up to ≈90%). The excellent lubricating properties of hairy NPs were further elucidated by the characterization of the tribofilm formed on the flat. These hairy NPs represent a new type of lubricating oil additives with high efficiency in friction and wear reduction.

  12. Oil-Soluble Polymer Brush Grafted Nanoparticles as Effective Lubricant Additives for Friction and Wear Reduction

    DOE PAGES

    Wright, Roger A. E.; Wang, Kewei; Qu, Jun; ...

    2016-06-06

    Developments of high performance lubricants are driven by increasingly growing industrial demands and environmental concerns. We demonstrate oil-soluble polymer brush-grafted inorganic nanoparticles (hairy NPs) as highly effective lubricant additives for friction and wear reduction. A series of oil-miscible poly(lauryl methacrylate) brush-grafted silica and titania NPs were synthesized by surface-initiated atom transfer radical polymerization. Moreover, these hairy NPs showed exceptional stability in poly(alphaolefin) (PAO) base oil; no change in transparency was observed after being kept at -20, 22, and 100°C for ≥55 days. High-contact stress ball-on-flat reciprocating sliding tribological tests at 100°C showed that addition of 1 wt% of hairy NPsmore » into PAO led to significant reductions in coefficient of friction (up to ≈40%) and wear volume (up to ≈90%). The excellent lubricating properties of hairy NPs were further elucidated by the characterization of the tribofilm formed on the flat. These hairy NPs represent a new type of lubricating oil additives with high efficiency in friction and wear reduction.« less

  13. Effect of commercial mineral-based additives on composting and compost quality.

    PubMed

    Himanen, M; Hänninen, K

    2009-08-01

    The effectiveness of two commercial additives meant to improve the composting process was studied in a laboratory-scale experiment. Improver A (sulphates and oxides of iron, magnesium, manganese, and zinc mixed with clay) and B (mixture of calcium hydroxide, peroxide, and oxide) were added to source-separated biowaste:peat mixture (1:1, v/v) in proportions recommended by the producers. The composting process (T, emissions of CO(2), NH(3), and CH(4)) and the quality of the compost (pH, conductivity, C/N ratio, water-soluble NH(4)-N and NO(3)-N, water- and NaOH-soluble low-weight carboxylic acids, nutrients, heavy metals and phytotoxicity to Lepidium sarivum) were monitored during one year. Compared with the control, the addition of improver B increased pH by two units, led to an earlier elimination of water-soluble ammonia, an increase in nitrates, a 10-fold increase in concentrations of acetic acid, and shortened phytotoxicity period by half; as negative aspect it led to volatilization of ammonia. The addition of improver A led to a longer thermophilic stage by one week and lower concentrations of low-weight carboxylic acids (both water- and NaOH-extractable) with formic and acetic of similar amounts, however, most of the aspects claimed by the improver's producer were not confirmed in this trial.

  14. Oil-Soluble Polymer Brush Grafted Nanoparticles as Effective Lubricant Additives for Friction and Wear Reduction.

    PubMed

    Wright, Roger A E; Wang, Kewei; Qu, Jun; Zhao, Bin

    2016-07-18

    The development of high performance lubricants has been driven by increasingly growing industrial demands and environmental concerns. Herein, we demonstrate oil-soluble polymer brush-grafted inorganic nanoparticles (hairy NPs) as highly effective lubricant additives for friction and wear reduction. A series of oil-miscible poly(lauryl methacrylate) brush-grafted silica and titania NPs were synthesized by surface-initiated atom transfer radical polymerization. These hairy NPs showed exceptional stability in poly(alphaolefin) (PAO) base oil; no change in transparency was observed after being kept at -20, 22, and 100 °C for ≥55 days. High-contact stress ball-on-flat reciprocating sliding tribological tests at 100 °C showed that addition of 1 wt % of hairy NPs into PAO led to significant reductions in coefficient of friction (up to ≈40 %) and wear volume (up to ≈90 %). The excellent lubricating properties of hairy NPs were further elucidated by the characterization of the tribofilm formed on the flat. These hairy NPs represent a new type of lubricating oil additives with high efficiency in friction and wear reduction.

  15. Simulation of flow in a continuous galvanizing bath: Part I. Thermal effects of ingot addition

    NASA Astrophysics Data System (ADS)

    Ajersch, F.; Ilinca, F.; Hétu, J.-F.

    2004-02-01

    A numerical analysis has been developed to simulate the velocity and temperature fields in an industrial galvanizing bath for the continuous coating of steel strip. Operating variables such as ingot addition, line speed, and inductor mixing were evaluated in order to determine their effect on the velocity and temperature distribution in the bath. The simulations were carried out using high-performance computational fluid-dynamics software developed at the Industrial Materials Institute of the National Research Council Canada (IMI-NRC) in solving the incompressible Navier-Stokes equations for steady-state and transient turbulent flow using the k-ɛ model. Cases with and without temperature-dependent density conditions were considered. It was found that the strip velocity does not alter the global flow pattern but modifies the velocities in the snout, near the strip, and near the sink and guide rolls. At a low inductor capacity, the effect of induced mixing is small but is considerably increased at the maximum inductor capacities used during ingot-melting periods. When considering the thermal effects, the flow is affected by variations in density especially near the inductors and the ingot, while little effect is observed near the sheet-and-roller region. Thermal effects are also amplified when the inductor operates at high capacity during ingot melting. The simulations allow visualization of regions of varying velocity and temperature fields and clearly illustrate the mixed and stagnant zones for different operating conditions.

  16. [Additive effect of marihuana and retrovirus in the anergy of natural killer cells in mice].

    PubMed

    Ongrádi, J; Specter, S; Horváth, A; Friedman, H

    1999-01-10

    Among the immunosuppressive effects of marijuana, impairment of natural killer cell activity is significant. HIV also inhibits these cells. Friend leukemia virus complex and its helper component Rowson-Parr virus induce early immunosuppression in mice resembling human AIDS, and late leukemia, providing a small animal AIDS model. Leukemia susceptible BALB/c and resistant C57BL/6 mice were infected with these viruses. At different time points, their natural killer cells separated from spleens were treated with 0 to 10 micrograms/ml tetrahydrocannabinol, subsequently mixed with Yac-1 target cells for 4 and 18 h. The natural killer cell activity in both mouse strains infected by either virus complex or helper virus weakened on days 2 to 4 postinfection, normalized by day 8 and enhanced on days 11 to 14. Natural killer cell activity upon the effect of low concentration (1.0 to 2.5 micrograms/ml) of tetrahydrocannabinol slightly increased in BALB/c, was unaffected in C57BL/6, especially in 18 h assays. In the combined effects of marijuana and retrovirus, damages by marijuana dominated over those of retroviruses. Inhibition or reactive enhancement of natural killer cell activity on the effect of viruses are similar to those of infected but marijuana-free counterparts, but on the level of uninfected cells treated with marijuana. The effects of marijuana and retrovirus are additive resulting in anergy of natural killer cells.

  17. REBOUNDx: A library for adding additional effects to N-body simulations

    NASA Astrophysics Data System (ADS)

    Tamayo, Daniel; Rein, Hanno; Shi, Pengshuai

    2016-05-01

    Many astrophysical applications involve additional perturbations beyond point-source gravity. We have recently developed REBOUNDx, a library for adding such effects in numerical simulations with the open-source N-body package REBOUND. Various implementations have different numerical properties that in general depend on the underlying integrator employed. In particular, I will discuss adding velocity-dependent/dissipative effects to widely used symplectic integrators, and how one can estimate the introduced numerical errors using the operator-splitting formalism traditionally applied to symplectic integrators. Finally, I will demonstrate how to use the code, and how the Python wrapper we have developed for REBOUND/REBOUNDx makes it easy to interactively leverage powerful analysis, visualization and parallelization libraries.

  18. Event-related potential practice effects on the Paced Auditory Serial Addition Test (PASAT)

    PubMed Central

    Rogers, Jeffrey M.; Fox, Alison M.

    2012-01-01

    Practice can change the nature and quality of a stimulus-response relationship. The current study observed the effects of repeated administration of the Paced Auditory Serial Addition Test (PASAT) in 12 healthy individuals, in an effort to establish distinct profiles associated with novel and practiced processing. Over four training sessions the mean number of correct responses on this demanding test of attention significantly improved and was approaching ceiling for most task conditions. Behavioural improvements were associated with significantly reduced amplitude of late Processing Negativity, a frontally distributed component of the event-related potential waveform associated with voluntary, limited-capacity activity within higher-order attentional systems. These results suggest that PASAT performance became more efficient as practice seemingly eased the strategic planning and coordination requirements the task places on frontally-mediated executive attention resources. The findings of the current study extend our understanding of the functional and behavioural mechanisms underlying the effects of practice. PMID:23717344

  19. Impact of Zn, Mg, Ni and Co elements on glass alteration: Additive effects

    NASA Astrophysics Data System (ADS)

    Aréna, H.; Godon, N.; Rébiscoul, D.; Podor, R.; Garcès, E.; Cabie, M.; Mestre, J.-P.

    2016-03-01

    The minor elements present in the nuclear glass composition or coming from the groundwater of the future repository may impact glass alteration. In this study, the effects of Zn, Mg, Ni and Co on the International Simple Glass (ISG) alteration were studied throughout 511 days of aqueous leaching experiments. The aim was to determine their additive or competitive effect on glass alteration and the nature of the alteration products. The four elements were introduced separately or altogether in solution as XCl2 chloride salts (X = Zn, Mg, Ni or Co) with monthly additions to compensate for their consumption. The alteration kinetics were determined by leachate analyses (ICP-AES) and alteration products were characterized in terms of composition, morphology and microstructure (SEM, TEM-EDX, ToF-SIMS and XRD). Results indicate that when they are introduced separately, Zn, Mg, Ni and Co have the same qualitative and quantitative effect on glass alteration kinetics and on pH: they form secondary phases leading to a pH decrease and a significant increase in glass alteration. The secondary phases were identified as silicates of the added X element: trioctahedral smectites with a stoichiometry of[(Si(4-a) Ala) (X(3-b) Alb) O10 (OH)2](a+b)- [Xc Nad Cae] (2c+d+2e) + with a = 0.11 to 0.45, b = 0.00 to 0.29, c = 0, d = 0.19 to 0.74 and e = 0.10 to 0.14. . It was shown that as pH stabilizes at a minimum value, X-silicates no longer precipitate, thus leading to a significant drop in the glass alteration rate. This pH value depends on X and it has been identified as being 8 for Mg-silicates, probably around 7.3 for Ni and Co-silicates and less than 6.2 for Zn-silicates. When tested together, the effects of these four elements on glass alteration are additive and lead to the formation of a mix of X-silicates that precipitate as long as their constitutive elements are available and the pH is above their respective minimum value. This study brings new quantitative information about the

  20. Effect of MnO2 Addition on the Electrical Properties of PNZST Ceramics

    NASA Astrophysics Data System (ADS)

    Yan, Yangxi; He, Hongliang; Feng, Yujun

    2014-05-01

    (Pb0.99Nb0.02)[(Zr0.70Sn0.30) x Ti1- x ]0.98O3 (PNZST) piezoelectric ceramics of pure perovskite structure were prepared by a conventional ceramic fabrication method, where x = 0.48-0.56. When x = 0.52, the ceramics exhibit a high piezoelectric coefficient ( d 33 ˜ 490), but the mechanical quality factor ( Q m) is only 72. To increase the Q m and not dramatically lower the d 33, MnO2 was chosen as the additive. The effects of adding MnO2 on the sinterability, structure, and electrical properties of PNZST ceramics were investigated in detail. With a small addition of MnO2 (≤0.6 wt.%), the Mn ions are homogeneously dissolved in the PNZST ceramic, leading to full densification when sintered at 1,300 °C. However, further addition of MnO2 prevents densification, causing a high porosity and small grain size. The doping of MnO2 transforms the phase structure from tetragonal to rhombohedral. The addition of MnO2 up to a maximum of 0.6 wt.% remarkably improves the mechanical quality factor ( Q m) of PNZST ceramics, simultaneously as well as maintaining a high d 33 and k p. PNZST with 0.6 wt.% MnO2 exhibits excellent electrical properties with piezoelectric coefficient d 33 = 392 pC/N, electromechanical coupling factor k p = 0.60, mechanical quality factor Q m = 1,050, dielectric constant ɛ r = 1,232, dielectric dissipation tan δ = 0.0058, and Curie temperature T C = 300 °C.

  1. Toxic effects of some synthetic food colorants and/or flavor additives on male rats.

    PubMed

    El-Wahab, Hanan Mohamed Fathy Abd; Moram, Gehan Salah El-Deen

    2013-03-01

    The objective of the present work was to evaluate the broadest toxic effect of some synthetic additives of colorants and/or flavors on different body organs and metabolic aspects in rats. A number of chemical food color and flavor additives are routinely added during processing to improve the aesthetic appearance of the dietary items. However, many of them are toxic after prolonged use. In this experiment, a total of 100 male albino rats of Spargue Dawley strain were divided into 10 groups: G(1) was fed basal diet and served as control, G(2): basal diet + Brilliant blue (blue dye, No. 2, 124 mg/kg diet), G(3): basal diet + carmoisine (red dye, No. 3, 70 mg/kg diet), G(4): basal diet + tartrazine (yellow dye, FD & C yellow No. 5, 75 mg/kg diet), G(5): basal diet + trans-anethole (4.5 g/kg diet) G(6): basal diet + propylene glycol (0.25 g/kg diet), G(7): basal diet + vanillin(1.25 g/kg diet), G(8): basal diet + Brilliant blue + propylene glycol, G(9): basal diet + carmoisine + trans-anethole, G(10): basal diet + tartrazine + vanillin for 42 successive days. All food colorants mixed with or without flavor additives induced a significant decrease in body weight, hemoglobin concentration and red blood cell count. Also there was a significant decrease in reduced glutathione content; glutathione-S-transferase and superoxide dismutase activities in both blood and liver compared to control group. On the other hand, a significant increase in serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase activities, bilirubin, urea, creatinine, total protein and albumin were observed in all test groups when compared to control group. Finally, it is advisable to limit the uses of these food colorants and/or food flavor additives especially those used by children.

  2. Effects of Ca addition on the uptake, translocation, and distribution of Cd in Arabidopsis thaliana.

    PubMed

    Zeng, Lihua; Zhu, Ting; Gao, Ya; Wang, Yutao; Ning, Chanjuan; Björn, Lars Olof; Chen, Da; Li, Shaoshan

    2017-05-01

    Cadmium (Cd) pollution poses a risk to human health for its accumulation in soil and crops, but this can be alleviated by calcium (Ca) addition. However, its mechanism remains unclear yet. In this study, Arabidopsis thaliana was used to explore the alleviating effects of Ca on Cd toxicity and its specific function during uptake, upward-translocation, and distribution of Cd. Supplementing plants with 5mM CaCl2 alleviated the intoxication symptoms caused by 50μM CdCl2, such as smaller leaves, early bolting and root browning. Ca addition decreased uptake of Cd, possibly by reducing the physical adsorption of Cd since the root cell membrane was well maintained and lignin deposition was decreased as well, and by decreasing symplastic Cd transport. Expression of the genes involved (AtZIP2 and AtZIP4) was also decreased. In addition, Ca accumulated in the plant shoot to help facilitating the upward-translocation of Cd, with evidence of higher translocation factor and expression of genes that were involved in Ca transport (AtPCR1) and Cd xylem loading (AtHMA2 and AtHMA4). Dithizone-staining of Cd in leaves showed that in Cd+Ca-treated plants, Ca addition initially protected the leaf stomata by preventing Cd from entering guard cells, but with prolonged Cd treatment facilitated the Cd accumulation around trichomes and maybe its excretion. We conclude that Ca promotes the upward-translocation of Cd and changes its distribution in leaves. The results may have relevance for bioremediation.

  3. Effect of jenny milk addition on the inhibition of late blowing in semihard cheese.

    PubMed

    Cosentino, C; Paolino, R; Valentini, V; Musto, M; Ricciardi, A; Adduci, F; D'Adamo, C; Pecora, G; Freschi, P

    2015-08-01

    The occurrence of late blowing defects in cheese produces negative effects on the quality and commercial value of the product. In this work, we verified whether the addition of raw jenny milk to bulk cow milk reduced the late blowing defects in semihard cheeses. During cheesemaking, different aliquots of jenny milk were poured into 2 groups of 4 vats, each containing a fixed amount of cow milk. A group of cheeses was created by deliberately contaminating the 4 vats with approximately 3 log10 cfu/mL milk of Clostridium tyrobutyricum CLST01. The other 4 vats, which were not contaminated, were used for a second group of cheeses. After 120 d of ripening, some physical, chemical, and microbiological parameters were evaluated on the obtained semihard cheeses. Differences in sensory properties among cheeses belonging to the uncontaminated group were evaluated by 80 regular consumers of cheese. Our results showed that the increasing addition of jenny milk to cow milk led to a reduction of pH and total bacterial count in both cheese groups, as well as C. tyrobutyricum spores that either grew naturally or artificially inoculated. We observed a progressive reduction of the occurrence of late blowing defects in cheese as consequence of the increasing addition of jenny milk during cheese making. Moreover, the addition of jenny milk did not affect the acceptability of the product, as consumers found no difference among cheeses concerning sensorial aspects. In conclusion, the important antimicrobial activity of lysozyme contained in jenny milk has been confirmed in the current research. It is recommend for use as a possible and viable alternative to egg lysozyme for controlling late blowing defects in cheese.

  4. Additive and non-additive effects of simulated leaf and inflorescence damage on survival, growth and reproduction of the perennial herb Arabidopsis lyrata.

    PubMed

    Puentes, Adriana; Ågren, Jon

    2012-08-01

    Herbivores may damage both leaves and reproductive structures, and although such combined damage may affect plant fitness non-additively, this has received little attention. We conducted a 2-year field experiment with a factorial design to examine the effects of simulated leaf (0, 12.5, 25, or 50% of leaf area removed) and inflorescence damage (0 vs. 50% of inflorescences removed) on survival, growth and reproduction in the perennial herb Arabidopsis lyrata. Leaf and inflorescence damage negatively and independently reduced flower, fruit and seed production in the year of damage; leaf damage also reduced rosette size by the end of the first season and flower production in the second year. Leaf damage alone reduced the proportion of flowers forming a fruit and fruit production per plant the second year, but when combined with inflorescence damage no such effect was observed (significant leaf × inflorescence damage interaction). Damage to leaves (sources) caused a greater reduction in future reproduction than did simultaneous damage to leaves and inflorescences (sinks). This demonstrates that a full understanding of the effects of herbivore damage on plant fitness requires that consequences of damage to vegetative and reproductive structures are evaluated over more than 1 year and that non-additive effects are considered.

  5. Modest additive effects of integrated vector control measures on malaria prevalence and transmission in western Kenya

    PubMed Central

    2013-01-01

    Background The effect of integrating vector larval intervention on malaria transmission is unknown when insecticide-treated bed-net (ITN) coverage is very high, and the optimal indicator for intervention evaluation needs to be determined when transmission is low. Methods A post hoc assignment of intervention-control cluster design was used to assess the added effect of both indoor residual spraying (IRS) and Bacillus-based larvicides (Bti) in addition to ITN in the western Kenyan highlands in 2010 and 2011. Cross-sectional, mass parasite screenings, adult vector populations, and cohort of active case surveillance (ACS) were conducted before and after the intervention in three study sites with two- to three-paired intervention-control clusters at each site each year. The effect of larviciding, IRS, ITNs and other determinants of malaria risk was assessed by means of mixed estimating methods. Results Average ITN coverage increased from 41% in 2010 to 92% in 2011 in the study sites. IRS intervention had significant added impact on reducing vector density in 2010 but the impact was modest in 2011. The effect of IRS on reducing parasite prevalence was significant in 2011 but was seasonal specific in 2010. ITN was significantly associated with parasite densities in 2010 but IRS application was significantly correlated with reduced gametocyte density in 2011. IRS application reduced about half of the clinical malaria cases in 2010 and about one-third in 2011 compare to non-intervention areas. Conclusion Compared with a similar study conducted in 2005, the efficacy of the current integrated vector control with ITN, IRS, and Bti reduced three- to five-fold despite high ITN coverage, reflecting a modest added impact on malaria transmission. Additional strategies need to be developed to further reduce malaria transmission. PMID:23870708

  6. Effect of additive metals, Sn, Ga, and In in Ag-Pd-Au-Cu alloys on initial bond strength of 4-META adhesive cement to these alloys.

    PubMed

    Goto, Shin-ichi; Churnjitapirom, Pornkiat; Miyagawa, Yukio; Ogura, Hideo

    2008-09-01

    The purpose of this study was to investigate the effects of three additives, Sn, Ga, and In, as well as the main constituents, Pd and Cu, of Ag-Pd-Au-Cu alloys on the initial bond strength of 4-META adhesive cement to these alloys. The Ag-Pd-Au-Cu alloys consisted of 20%, 30% or 40% Pd, and 10%, 15% or 20% Cu, 20% Au, and Ag as balance. Besides, additive metals (Sn, Ga, and In) of 2% and 4% were added to these compositions. The addition of three additives, in general, increased the initial bond strength of the cement in comparison to the mother compositions (0% additives), although the degrees of effectiveness of the three additives were different and varied with their contents. Among these additives, a remarkable increase in bond strength was observed with the addition of In. The increase in Cu content, in many cases, resulted in an increase in bond strength at high Pd contents (30% and 40%), but a decrease at low Pd content (20%) in some cases. The positive effects of the three additives and Cu could be due to the formation of a suitable oxide layer for strong bonding with 4-META.

  7. Litter Decomposition in a Semiarid Dune Grassland: Neutral Effect of Water Supply and Inhibitory Effect of Nitrogen Addition

    PubMed Central

    Li, Yulin; Ning, Zhiying; Cui, Duo; Mao, Wei; Bi, Jingdong; Zhao, Xueyong

    2016-01-01

    Background The decomposition of plant material in arid ecosystems is considered to be substantially controlled by water and N availability. The responses of litter decomposition to external N and water, however, remain controversial, and the interactive effects of supplementary N and water also have been largely unexamined. Methodology/Principal Findings A 3.5-year field experiment with supplementary nitrogen and water was conducted to assess the effects of N and water addition on mass loss and nitrogen release in leaves and fine roots of three dominant plant species (i.e., Artemisia halondendron, Setaria viridis, and Phragmites australis) with contrasting substrate chemistry (e.g. N concentration, lignin content in this study) in a desertified dune grassland of Inner Mongolia, China. The treatments included N addition, water addition, combination of N and water, and an untreated control. The decomposition rate in both leaves and roots was related to the initial litter N and lignin concentrations of the three species. However, litter quality did not explain the slower mass loss in roots than in leaves in the present study, and thus warrant further research. Nitrogen addition, either alone or in combination with water, significantly inhibited dry mass loss and N release in the leaves and roots of the three species, whereas water input had little effect on the decomposition of leaf litter and fine roots, suggesting that there was no interactive effect of supplementary N and water on litter decomposition in this system. Furthermore, our results clearly indicate that the inhibitory effects of external N on dry mass loss and nitrogen release are relatively strong in high-lignin litter compared with low-lignin litter. Conclusion/Significance These findings suggest that increasing precipitation hardly facilitates ecosystem carbon turnover but atmospheric N deposition can enhance carbon sequestration and nitrogen retention in desertified dune grasslands of northern China

  8. A critical review on the spray drying of fruit extract: effect of additives on physicochemical properties.

    PubMed

    Krishnaiah, Duduku; Nithyanandam, Rajesh; Sarbatly, Rosalam

    2014-01-01

    Spray drying accomplishes drying while particles are suspended in the air and is one method in the family of suspended particle processing systems, along with fluid-bed drying, flash drying, spray granulation, spray agglomeration, spray reaction, spray cooling, and spray absorption. This drying process is unique because it involves both particle formation and drying. The present paper reviews spray drying of fruit extracts, such as acai, acerola pomace, gac, mango, orange, cactus pear, opuntia stricta fruit, watermelon, and durian, and the effects of additives on physicochemical properties such as antioxidant activity, total carotenoid content, lycopene and β-carotene content, hygroscopy, moisture content, volatile retention, stickiness, color, solubility, glass transition temperature, bulk density, rehydration, caking, appearance under electron microscopy, and X-ray powder diffraction. The literature clearly demonstrates that the effect of additives and encapsulation play a vital role in determining the physicochemical properties of fruit extract powder. The technical difficulties in spray drying of fruit extracts can be overcome by modifying the spray dryer design. It also reveals that spray drying is a novel technology for converting fruit extract into powder form.

  9. The effect of Tricresyl-Phosphate (TCP) as an additive on wear of Iron (Fe)

    NASA Technical Reports Server (NTRS)

    Ghose, Hiren M.; Ferrante, John; Honecy, Frank C.

    1987-01-01

    The effect of tricresyl phosphate (TCP) as an antiwear additive in lubricant trimethyol propane triheptanoate (TMPTH) was investigated. The objective was to examine step loading wear by use of surface analysis, wetting, and chemical bonding changes in the lubricant. The investigation consisted of steploading wear studies by a pin or disk tribometer, the effects on wear related to wetting by contact angle and surface tension measurements of various liquid systems, the chemical bonding changes between lubricant and TCP chromatographic analysis, and by determining the reaction between the TCP and metal surfaces through wear scar analysis by Auger emission spectroscopy (AES). The steploading curve for the base fluid alone shows rapid increase of wear rate with load. The steploading curve for the base fluid in presence of 4.25 percent by volume TCP under dry air purge has shown a great reduction of wear rate with all loads studied. It has also been found that the addition of 4.25 percent by volume TCP plus 0.33 percent by volume water to the base lubricant under N2 purge also greatly reduces the wear rate with all loads studied. AES surface analysis reveals a phosphate type wear resistant film, which greatly increases load-bearing capacity, formed on the iron disk. Preliminary chromatographic studies suggest that this film forms either because of ester oxidation or TCP degradation. Wetting studies show direct correlation between the spreading coefficient and the wear rate.

  10. The additive effect on suicidality of family history of suicidal behavior and early traumatic experiences.

    PubMed

    Lopez-Castroman, J; Guillaume, S; Olié, E; Jaussent, I; Baca-García, E; Courtet, P

    2015-01-01

    Family history of suicidal behavior and personal history of childhood abuse are reported risk factors for suicide attempts and suicide completion. We aim to quantify the additive effect of family history of suicidal behavior and different subtypes of childhood abuse on suicidal behavior. We examined a sample of 496 suicide attempters, comparing individuals with family history of suicidal behavior and personal history of childhood (physical or sexual) abuse, individuals with family history of suicidal behavior only, individuals with history of early traumatic experiences only, and individuals with none of these two risk factors with regards to suicidal features. An additive effect was found for the age at the first attempt in suicide attempters with both family history of suicidal behavior and either physical or sexual abuse. No significant interactions were found between family history of suicidal behavior and childhood trauma in relation to any characteristics of suicidal behavior. Subjects presenting family history of suicidal behavior and childhood abuse attempt suicide earlier in life than subjects with just one or none of them, particularly if they were sexually abused. Other suicidality indexes were only partially or not associated with this combination of risk factors. A careful assessment of patients with both family history of suicidal behavior and childhood abuse could help to prevent future suicide attempts, particularly in young people.

  11. The effect of accelerated ageing on performance properties of addition type silicone biomaterials.

    PubMed

    Stathi, K; Tarantili, P A; Polyzois, G

    2010-05-01

    The UV-protection provided to addition type silicone elastomers by various colorants, such as conventional dry earth pigments, as well as the so called "functional or reactive" pigments, was investigated. Moreover, the effect of a UV light absorber and a silica filler was also explored. Under the experimental parameters of this work, the exposure of silicone to UV radiation resulted in some changes of the IR absorbance, thermal decomposition after 400 degrees C, T(g) and tensile properties, whereas the storage modulus of samples was not affected. The obtained spectroscopic data, as well as the results of TGA and storage modulus, were interpreted by assuming that chain scission takes place during aging, whereas the improvement of tensile strength allows the hypothesis of a post-curing process, initiated by UV radiation. Therefore, the increase of T(g) could partly be due to the above reason and, furthermore, to the contribution of a rearrangement of chain fragments within the free volume of the elastomeric material. Regarding the evaluation of various coloring agents used in this work, the obtained results show that dry pigments are more sensitive to accelerated ageing conditions in comparison with functional liquid pigments. Moreover, the hydrophobic character of silicone matrix is enhanced, with the addition of this type pigments because of the vinyl functional silanes groups present in their chemical structure. Finally, it should be noted that the incorporation of silica nanofiller did not seem to prevent the silicone elastomer from degradation upon UV irradiation, but showed a significant reinforcing effect.

  12. Effect of PAC addition on immersed ultrafiltration for the treatment of algal-rich water.

    PubMed

    Zhang, Yan; Tian, Jiayu; Nan, Jun; Gao, ShanShan; Liang, Heng; Wang, Meilian; Li, Guibai

    2011-02-28

    The aim of this study was to evaluate the effect of powdered activated carbon (PAC) addition on the treatment of algal-rich water by immersed ultrafiltration (UF), in terms of permeate quality and membrane fouling. Experiments were performed with a hollow-fiber polyvinyl chloride ultrafiltration membrane at a laboratory scale, 20-25°C and 10 L/(m(2) h) constant permeate flux. UF could achieve an absolute removal of Microcystis aeruginosa cells, but a poor removal of algogenic organic matter (AOM) released into water, contaminants responsible for severe membrane fouling. The addition of 4 g/L PAC to the immersed UF reactor significantly alleviated the development of trans-membrane pressure and enhanced the removal of dissovled organic carbon (by 10.9±1.7%), UV(254) (by 27.1±1.7%), and microcystins (expressed as MC-LR(eq), by 40.8±4.2%). However, PAC had little effect on the rejection of hydrophilic high molecular weight AOM such as carbohydrates and proteins. It was also identified that PAC reduced the concentrations of carbohydrates and proteins in the reactor due to decreased light intensity, as well as the MC-LR(eq) concentration by PAC adsorption.

  13. Effects of insoles and additional shock absorption foam on the cushioning properties of sport shoes.

    PubMed

    Chiu, Hung-Ta; Shiang, Tzyy-Yuang

    2007-05-01

    The purpose of this study was to investigate the effects of insoles and additional shock absorption foam on the cushioning properties of various sport shoes with an impact testing method. Three commercial sport shoes were used in this study, and shock absorption foam (TPE5020; Vers Tech Science Co. Ltd., Taiwan) with 2-mm thickness was placed below the insole in the heel region for each shoe. Eight total impacts with potential energy ranged from 1.82 to 6.08 J were performed onto the heel region of the shoe. The order of testing conditions was first without insole, then with insole, and finally interposing the shock absorption foam for each shoe. Peak deceleration of the striker was measured with an accelerometer attached to the striker during impact. The results of this study seemed to show that the insole or additional shock absorption foam could perform its shock absorption effect well for the shoes with limited midsole cushioning. Further, our findings showed that insoles absorbed more, even up to 24-32% of impact energy under low impact energy. It seemed to indicate that insoles play a more important role in cushioning properties of sport shoes under a low impact energy condition.

  14. Drag reducing effects of polymer additives in a plate heat exchanger for the OTEC system

    SciTech Connect

    Kim, N.; Yoon, S.; Kim, C.; Seo, T.

    1999-07-01

    Experiments were undertaken for a 15kW Alfa-Laval plate heat exchanger utilizing polyethylene oxide as a polymer additive. Concentrations of polymer additives were 5, 10, 20, 30, 40, 50, 100, 200 and 400 wppm at 25 C and mass flow rates were 0.6kg/s, 0.7kg/s, 0.8kg/s and 0.9kg/s in normal operating ranges of the plate heat exchanger. The maximum effects of drag reductions were found at 20 wppm polymer concentration and at approximately 0.7kg/s of mass flow rate. The results show that there exist optimum polymer concentration and at approximately 0.7kg/s of mass flow rate. The results show that there exist optimum polymer concentration and mass flow rate for the plate heat exchanger for maximum drag reduction effects. In most cases, drag reduction of approximately 20% has been obtained. It means considerable savings in pumping power for a large size OTEC plant.

  15. Effect of Sn addition on the microstructure and superelasticity in Ti-Nb-Mo-Sn alloys.

    PubMed

    Zhang, D C; Yang, S; Wei, M; Mao, Y F; Tan, C G; Lin, J G

    2012-09-01

    Ti-7.5Nb-4Mo-xSn (x=0-4at%) alloys were developed as the biomedical materials. The effect of the Sn content on the microstructure and superelasticity of the alloys was investigated. It is found that Sn is a strong stabilizer of the β phase, which is effective in suppressing the formation of α″ and ω phases in the alloys. Moreover, the Sn addition has a significant impact on the mechanical properties of the alloys. With the increase of Sn addition, the yield stress of the alloys increase, but their elastic modulus, the fracture strength and the ductility decrease, and the deformation mode of the alloys changes from (322) twining to α″ transformation and then to slip. The Ti-7.5Nb-4Mo-1Sn and Ti-7.5Nb-4Mo-3Sn alloys exhibit a good superelasticity with a high σ(SIM) due to the relatively high athermal ω phases containing or the solution hardening at room temperature. Under the maximum strain of 5%, Ti-7.5Nb-4Mo-3Sn (at%) alloy exhibits higher super elastic stability than that of Ti-7.5Nb-4Mo-1Sn alloy.

  16. Amorphouslike chemical vapor deposited tungsten diffusion barrier for copper metallization and effects of nitrogen addition

    NASA Astrophysics Data System (ADS)

    Chang, Kow-Ming; Yeh, Ta-Hsun; Deng, I.-Chung; Shih, Chieh-Wen

    1997-08-01

    In this article, we propose an amorphouslike chemical vapor deposited tungsten (CVD-W) thin film as a diffusion barrier for copper metallization. Experimental results gave no evidence of interdiffusion and structural change for Cu/amorphouslike CVD-W/Si samples annealed up to 675 °C for 30 min in N2. At higher temperatures (700 °C), Cu penetration results in the formation of η''-Cu3Si precipitates at the CVD-W/Si interface. This is due to the crystallization of the amorphouslike CVD-W film above 650 °C, rendering the grain-boundary structure and, hence, fast pathways for Cu diffusion. The Cu/amorphouslike CVD-W/p+n diodes, thus, sustain large increases in reverse leakage current. In addition, the effects of nitrogen addition by using an in situ nitridation on the amorphouslike CVD-W film are also discussed. The effectiveness of the nitrided barrier is attributed to the blocking of the grain boundaries in the tungsten film by nitrogen atoms. This slows down Cu diffusion significantly. Physical and chemical analyses indicate that interfaces in the Cu/WNx/W/Si multilayer maintain their integrity while the annealing is carried out at 750 °C. Moreover, the reverse leakage current densities of Cu/WNx/W/p+n diodes remain at 10-7 A/cm2 after 725 °C annealing.

  17. Effects of Perovskite Additives on the Electromagnetic Properties of Z-Type Hexaferrites

    NASA Astrophysics Data System (ADS)

    Lijun Jia,; Yingming Tang,; Huaiwu Zhang,; Pingfeng Deng,; Yingli Liu,; Baoyuan Liu,

    2010-06-01

    In order to modulate the electromagnetic properties of Z-type hexaferrites for high-frequency applications, perovskite additives have been introduced. The effects of these additives on the phase composition, densification, microstructures and electromagnetic properties of the ceramics have been investigated. The results indicate that Ba0.5Sr0.5TiO3 (BST) can promote the grain growth and enhance the sintering by increasing the displacement of ions due to the lattice distortion, which is a result of the solid solubility of Ti4+ in the hexaferrite. The increase of grain size and bulk density and the decrease of magnetocrystalline anisotropy give rise to the improvement of the static permeability. Meanwhile, the dielectric constant increases with BST content due to the changing of the valence of Fe ions in octahedral sites and the polarization of the perovskite phase. In contrast, Pb0.95Sr0.05(Zr0.52Ti0.48)O3 (PZT) is not effective for improving the electromagnetic properties of hexaferrites due to the strong coupling of Ti-O and Zr-O.

  18. Additive effects of serotonin transporter and tryptophan hydroxylase-2 gene variation on emotional processing.

    PubMed

    Herrmann, Martin J; Huter, Theresa; Müller, Frauke; Mühlberger, Andreas; Pauli, Paul; Reif, Andreas; Renner, Tobias; Canli, Turhan; Fallgatter, Andreas J; Lesch, Klaus-Peter

    2007-05-01

    Prior studies reported that functional variants of both the serotonin transporter (5-HTT) and tryptophan hydroxylase-2 genes (TPH2), 2 key regulators of the serotonergic signaling pathway, modulate amygdala activation during emotional processing. We addressed the question whether these 2 gene variants modulate each other, using an emotional picture-processing task. Specifically, we measured event-related potentials (ERPs) during a passive emotional picture perception task, focusing on ERPs for the early posterior negativity (EPN) around 240 ms and for the slow wave starting at 315 ms. We found evidence for increased neural activity at 240 ms in individuals who carried 1 or 2 copies of the low-expression short variant of the 5-HTT. Carriers of T variant of the TPH2 also showed a tendency toward increased neural activity at 240 ms. Moreover, we observed an additive effect of both genotypes for EPN, with highest neural activity to emotional stimuli in individuals carrying combination of both short variant of 5-HTT and T variant of TPH2. Our results indicate that both the 5-HTT and the TPH2 genotypes modulate the sensory encoding of affective stimuli during early steps of visual processing and reveal additive effects of 2 genes in the serotonergic control of emotion regulation.

  19. NMR characterization of cellulose acetate: chemical shift assignments, substituent effects, and chemical shift additivity.

    PubMed

    Kono, Hiroyuki; Hashimoto, Hisaho; Shimizu, Yuuichi

    2015-03-15

    A series of cellulose acetates (CA) with degrees of substitution (DS) ranging from 2.92-0.92 dissolved in dimethylsulfoxide (DMSO)-d6 and cellulose dissolved in tetrabutylammonium fluoride (TBAF)/DMSO-d6 were investigated by two-dimensional NMR spectroscopy. The NMR spectroscopic analysis allowed the determination of the (1)H and (13)C NMR chemical shifts of the eight anhydroglucose units (AGUs) that contain CA: 2,3,6-tri-, 2,3-di-, 2,6-di-, 3,6-di-, 2-mono-, 3-mono-, 6-mono-, and unacetylated AGUs. A comparative analysis of the chemical shift data revealed the substituent effect of acetyl groups at the 2-, 3-, and 6-positions on the (1)H and (13)C nuclei in the same AGU. In addition, chemical shift additivity could be applied to the (1)H and (13)C chemical shifts of CA because the chemical shifts of the diacetylated and triacetylated AGUs could be almost completely explained by the acetyl substituent effects at the 2-, 3-, and 6-positions.

  20. A study of the effects of disk flexibility on the rotordynamics of the space shuttle main engine turbo-pumps

    NASA Technical Reports Server (NTRS)

    Flowers, George T.

    1989-01-01

    Rotor dynamical analyses are typically performed using rigid disk models. Studies of rotor models in which the effects of disk flexibility were included indicate that is may be an important effect for many systems. This issue is addressed with respect to the Space Shuttle Main Engine high pressure turbo-pumps. Finite element analyses have been performed for a simplified free-free flexible disk rotor model and the modes and frequencies compared to those of a rigid disk model. The simple model was then extended to a more sophisticated HPTOP rotor model and similar results were observed. Equations were developed that are suitable for modifying the current rotordynamical analysis program to account for disk flexibility. Some conclusions are drawn from the results of this work as to the importance of disk flexibility on the HPTOP rotordynamics and some recommendations are given for follow-up research in this area.

  1. Effect of Additives and pH on the Formation of Carbonate Mineral by CO2 Sequestration of Cement Paste

    NASA Astrophysics Data System (ADS)

    Lee, J. H.; Hwang, J.; Lee, H.; Son, B. S.; Oh, J.

    2015-12-01

    CO2 in the atmosphere causes a global warming that is a big issue nowadays. Many studies of CO2 capture and storage (CCS) technologies have been studied all over the world. Waste cement is a good source for aqueous carbonation because it is rich in calcium. Therefore, this study was performed to develop the aqueous carbonation method for waste cement powder. Cement paste was made with water/cement ratio of 6:4 and cured for 28 days in water bath. The cement paste was pulverized into a fine powder sizing less than 0.15 mm. To study effect of additives and pH on the formation of carbonate minerals, aqueous carbonation experiments were conducted. The mineral compositions and morphology of carbonate mineral were identified by XRD and SEM/EDS analysis. 1.0 M NaCl and 0.25 M MgCl2 were applied as additives. Aqueous carbonation experiment was conducted with injecting pure CO2 gas (99.9%) to a reactor containing 200 ㎖ of reacting solution. The pH of reacting solution was controled to determine formational condition of carbonate minerals. In 0.25 M MgCl2 solution, calcite was dominant mineral at high pH. More aragonite, however, formed as decreasing pH of solution with injection of CO2. The presence of Mg2+ in solution makes aragonite more dominant than calcite. Aragonite was mainly formed at the high pH of solution with 1.0 M NaCl additive, whereas calcite was more preponderant mineral than aragonite as falling pH. It show that unstable aragonite transformed to calcite as decreasing pH. In no additive solution, vaterite was dominantly formed at the initial stage of experiement, but unstable vaterite transformed to well crystallized calcite with further carbonation.

  2. Conflict-Specific Aging Effects Mainly Manifest in Early Information Processing Stages-An ERP Study with Different Conflict Types.

    PubMed

    Korsch, Margarethe; Frühholz, Sascha; Herrmann, Manfred

    2016-01-01

    Aging is usually accompanied by alterations of cognitive control functions such as conflict processing. Recent research suggests that aging effects on cognitive control seem to vary with degree and source of conflict, and conflict specific aging effects on performance measures as well as neural activation patterns have been shown. However, there is sparse information whether and how aging affects different stages of conflict processing as indicated by event related potentials (ERPs) such as the P2, N2 and P3 components. In the present study, 19 young and 23 elderly adults performed a combined Flanker conflict and stimulus-response-conflict (SRC) task. Analysis of the reaction times (RTs) revealed an increased SRC related conflict effect in elderly. ERP analysis furthermore demonstrated an age-related increase of the P2 amplitude in response to the SRC task. In addition, elderly adults exhibited an increased P3 amplitude modulation induced by incongruent SRC and Flanker conflict trials.

  3. Conflict-Specific Aging Effects Mainly Manifest in Early Information Processing Stages—An ERP Study with Different Conflict Types

    PubMed Central

    Korsch, Margarethe; Frühholz, Sascha; Herrmann, Manfred

    2016-01-01

    Aging is usually accompanied by alterations of cognitive control functions such as conflict processing. Recent research suggests that aging effects on cognitive control seem to vary with degree and source of conflict, and conflict specific aging effects on performance measures as well as neural activation patterns have been shown. However, there is sparse information whether and how aging affects different stages of conflict processing as indicated by event related potentials (ERPs) such as the P2, N2 and P3 components. In the present study, 19 young and 23 elderly adults performed a combined Flanker conflict and stimulus-response-conflict (SRC) task. Analysis of the reaction times (RTs) revealed an increased SRC related conflict effect in elderly. ERP analysis furthermore demonstrated an age-related increase of the P2 amplitude in response to the SRC task. In addition, elderly adults exhibited an increased P3 amplitude modulation induced by incongruent SRC and Flanker conflict trials. PMID:27014059

  4. Using additive modelling to quantify the effect of chemicals on phytoplankton diversity and biomass.

    PubMed

    Viaene, K P J; De Laender, F; Van den Brink, P J; Janssen, C R

    2013-04-01

    Environmental authorities require the protection of biodiversity and other ecosystem properties such as biomass production. However, the endpoints listed in available ecotoxicological datasets generally do not contain these two ecosystem descriptors. Inferring the effects of chemicals on such descriptors from micro- or mesocosm experiments is often hampered by inherent differences in the initial biodiversity levels between experimental units or by delayed community responses. Here we introduce additive modelling to establish the effects of a chronic application of the herbicide linuron on 10 biodiversity indices and phytoplankton biomass in microcosms. We found that communities with a low (high) initial biodiversity subsequently became more (less) diverse, indicating an equilibrium biodiversity status in the communities considered here. Linuron adversely affected richness and evenness while dominance increased but no biodiversity indices were different from the control treatment at linuron concentrations below 2.4 μg/L. Richness-related indices changed at lower linuron concentrations (effects noticeable from 2.4 μg/L) than other biodiversity indices (effects noticeable from 14.4 μg/L) and, in contrast to the other indices, showed no signs of recovery following chronic exposure. Phytoplankton biomass was unaffected by linuron due to functional redundancy within the phytoplankton community. Comparing thresholds for biodiversity with conventional toxicity test results showed that standard ecological risk assessments also protect biodiversity in the case of linuron.

  5. Sunlight Effects on Immune System: Is There Something Else in addition to UV-Induced Immunosuppression?

    PubMed Central

    Paz, M. L.; Leoni, J.

    2016-01-01

    Sunlight, composed of different types of radiation, including ultraviolet wavelengths, is an essential source of light and warmth for life on earth but has strong negative effects on human health, such as promoting the malignant transformation of skin cells and suppressing the ability of the human immune system to efficiently detect and attack malignant cells. UV-induced immunosuppression has been extensively studied since it was first described by Dr. Kripke and Dr. Fisher in the late 1970s. However, skin exposure to sunlight has not only this and other unfavorable effects, for example, mutagenesis and carcinogenesis, but also a positive one: the induction of Vitamin D synthesis, which performs several roles within the immune system in addition to favoring bone homeostasis. The impact of low levels of UV exposure on the immune system has not been fully reported yet, but it bears interesting differences with the suppressive effect of high levels of UV radiation, as shown by some recent studies. The aim of this article is to put some ideas in perspective and pose some questions within the field of photoimmunology based on established and new information, which may lead to new experimental approaches and, eventually, to a better understanding of the effects of sunlight on the human immune system. PMID:28070504

  6. Sunlight Effects on Immune System: Is There Something Else in addition to UV-Induced Immunosuppression?

    PubMed

    González Maglio, D H; Paz, M L; Leoni, J

    2016-01-01

    Sunlight, composed of different types of radiation, including ultraviolet wavelengths, is an essential source of light and warmth for life on earth but has strong negative effects on human health, such as promoting the malignant transformation of skin cells and suppressing the ability of the human immune system to efficiently detect and attack malignant cells. UV-induced immunosuppression has been extensively studied since it was first described by Dr. Kripke and Dr. Fisher in the late 1970s. However, skin exposure to sunlight has not only this and other unfavorable effects, for example, mutagenesis and carcinogenesis, but also a positive one: the induction of Vitamin D synthesis, which performs several roles within the immune system in addition to favoring bone homeostasis. The impact of low levels of UV exposure on the immune system has not been fully reported yet, but it bears interesting differences with the suppressive effect of high levels of UV radiation, as shown by some recent studies. The aim of this article is to put some ideas in perspective and pose some questions within the field of photoimmunology based on established and new information, which may lead to new experimental approaches and, eventually, to a better understanding of the effects of sunlight on the human immune system.

  7. Effects of Coating Materials and Mineral Additives on Nitrate Reduction by Zerovalent Iron

    NASA Astrophysics Data System (ADS)

    Kim, K. H.; Jeong, H. Y.; Lee, S.; Kang, N.; Choi, H. J.; Park, M.

    2015-12-01

    In efforts to facilitate nitrate removal, a variety of coating materials and mineral additives were assessed for their effects on the nitrate reduction by zerovalent iron (ZVI). Coated ZVIs were prepared by reacting Fe particles with Cr(III), Co(II), Ni(II), Cu(II), and S(-II) solutions under anoxic conditions, with the resultant materials named Cr/Fe, Co/Fe, Ni/Fe, Cu/Fe, and FeS/Fe, respectively. The mineral additives used, synthesized or purchased, included goethite, magnetite, and hydrous ferric oxide (HFO). Kinetic experiments were performed using air-tight serum vials containing 1.0 g Fe (uncoated or coated forms) in 15 mL of 100 mg NO3×N/L solutions with pH buffered at 7.0. To monitor the reaction progress, the solution phase was analyzed for NO3-, NO2-, and NH4+ on an ion chromatography, while the headspace was analyzed for H2, N2, and O2 on a gas chromatography. By uncoated Fe, ca. 60% of nitrate was reductively transformed for 3.6 h, with NH4+ being the predominant product. Compared with uncoated one, Cr/Fe, Co/Fe, and Cu/Fe showed faster removal rates of nitrate. The observed reactivity enhancement was thought to result from additional reduction of nitrate by H atoms adsorbed on the surface of Cr, Co, or Cu metal. In contrast, both Ni/Fe and FeS/Fe showed slower removal of nitrate than uncoated Fe. In both cases, the coating, which highly disfavors the adsorption of nitrate, would form on the Fe surface. When goethite, HFO, and magnetite were amended, the nitrate reduction by Fe was significantly increased, with the effect being most evident with HFO. Although not capable of reducing nitrate, the mineral additives would serve as crystal nuclei for the corrosion products of Fe, thus making the development of passivation layers on the Fe surface less. In the future, we will perform a kinetic modeling of the experimental data to assess the relative contribution of multiple reaction paths in the nitrate reduction by Fe.

  8. Additive effects of beta-alanine and sodium bicarbonate on upper-body intermittent performance.

    PubMed

    Tobias, Gabriel; Benatti, Fabiana Braga; de Salles Painelli, Vitor; Roschel, Hamilton; Gualano, Bruno; Sale, Craig; Harris, Roger C; Lancha, Antonio Herbert; Artioli, Guilherme Gianinni

    2013-08-01

    We examined the isolated and combined effects of beta-alanine (BA) and sodium bicarbonate (SB) on high-intensity intermittent upper-body performance in judo and jiu-jitsu competitors. 37 athletes were assigned to one of four groups: (1) placebo (PL)+PL; (2) BA+PL; (3) PL+SB or (4) BA+SB. BA or dextrose (placebo) (6.4 g day⁻¹) was ingested for 4 weeks and 500 mg kg⁻¹ BM of SB or calcium carbonate (placebo) was ingested for 7 days during the 4th week. Before and after 4 weeks of supplementation, the athletes completed four 30-s upper-body Wingate tests, separated by 3 min. Blood lactate was determined at rest, immediately after and 5 min after the 4th exercise bout, with perceived exertion reported immediately after the 4th bout. BA and SB alone increased the total work done in +7 and 8 %, respectively. The co-ingestion resulted in an additive effect (+14 %, p < 0.05 vs. BA and SB alone). BA alone significantly improved mean power in the 2nd and 3rd bouts and tended to improve the 4th bout. SB alone significantly improved mean power in the 4th bout and tended to improve in the 2nd and 3rd bouts. BA+SB enhanced mean power in all four bouts. PL+PL did not elicit any alteration on mean and peak power. Post-exercise blood lactate increased with all treatments except with PL+PL. Only BA+SB resulted in lower ratings of perceived exertion (p = 0.05). Chronic BA and SB supplementation alone equally enhanced high-intensity intermittent upper-body performance in well-trained athletes. Combined BA and SB promoted a clear additive ergogenic effect.

  9. Seasonal variation exceeds effects of salmon carcass additions on benthic food webs in the Elwha River

    USGS Publications Warehouse

    Morley, S.A.; Coe, H.J.; Duda, J.J.; Dunphy, L.S.; McHenry, M.L.; Beckman, B.R.; Elofson, M.; Sampson, E. M.; Ward, L.

    2016-01-01

    Dam removal and other fish barrier removal projects in western North America are assumed to boost freshwater productivity via the transport of marine-derived nutrients from recolonizing Pacific salmon (Oncorhynchus spp.). In anticipation of the removal of two hydroelectric dams on the Elwha River in Washington State, we tested this hypothesis with a salmon carcass addition experiment. Our study was designed to examine how background nutrient dynamics and benthic food webs vary seasonally, and how these features respond to salmon subsidies. We conducted our experiment in six side channels of the Elwha River, each with a spatially paired reference and treatment reach. Each reach was sampled on multiple occasions from October 2007 to August 2008, before and after carcass placement. We evaluated nutrient limitation status; measured water chemistry, periphyton, benthic invertebrates, and juvenile rainbow trout (O. mykiss) response; and traced salmon-derived nutrient uptake using stable isotopes. Outside of winter, algal accrual was limited by both nitrogen and phosphorous and remained so even in the presence of salmon carcasses. One month after salmon addition, dissolved inorganic nitrogen levels doubled in treatment reaches. Two months after addition, benthic algal accrual was significantly elevated. We detected no changes in invertebrate or fish metrics, with the exception of 15N enrichment. Natural seasonal variability was greater than salmon effects for the majority of our response metrics. Yet seasonality and synchronicity of nutrient supply and demand are often overlooked in nutrient enhancement studies. Timing and magnitude of salmon-derived nitrogen utilization suggest that uptake of dissolved nutrients was favored over direct consumption of carcasses. The highest proportion of salmon-derived nitrogen was incorporated by herbivores (18–30%) and peaked 1–2 months after carcass addition. Peak nitrogen enrichment in predators (11–16%) occurred 2–3

  10. Effects of protonation and C5 methylation on the electrophilic addition reaction of cytosine: a computational study.

    PubMed

    Jin, Lingxia; Wang, Wenliang; Hu, Daodao; Min, Suotian

    2013-01-10

    The mechanism for the effects of protonation and C5 methylation on the electrophilic addition reaction of Cyt has been explored by means of CBS-QB3 and CBS-QB3/PCM methods. In the gas phase, three paths, two protonated paths (N3 and O2 protonated paths B and C) as well as one neutral path (path A), were mainly discussed, and the calculated results indicate that the reaction of the HSO(3)(-) group with neutral Cyt is unlikely because of its high activation free energy, whereas O2-protonated path (path C) is the most likely to occur. In the aqueous phase, path B is the most feasible mechanism to account for the fact that the activation free energy of path B decreases compared with the corresponding path in the gas phase, whereas those of paths A and C increase. The main striking results are that the HSO(3)(-) group directly interacts with the C5═C6 bond rather than the N3═C4 bond and that the C5 methylation, compared with Cyt, by decreasing values of global electrophilicity index manifests that C5 methylation forms are less electrophilic power as well as by decreasing values of NPA charges on C5 site of the intermediates make the trend of addition reaction weaken, which is in agreement with the experimental observation that the rate of 5-MeCyt reaction is approximately 2 orders of magnitude slower than that of Cyt in the presence of bisulfite. Apart from cis and trans isomers, the rare third isomer where both the CH(3) and SO(3) occupy axial positions has been first found in the reactions of neutral and protonated 5-MeCyt with the HSO(3)(-) group. Furthermore, the transformation of the third isomer from the cis isomer can occur easily.

  11. Effect of SPL (Spent Pot Liner) and its main components on root growth, mitotic activity and phosphorylation of Histone H3 in Lactuca sativa L.

    PubMed

    Freitas, Aline Silva; Fontes Cunha, Isabela Martinez; Andrade-Vieira, Larissa Fonseca; Techio, Vânia Helena

    2016-02-01

    Spent Pot Liner (SPL) is a solid waste from the aluminum industry frequently disposed of in industrial landfills; it can be leached and contaminate the soil, sources of drinking water and plantations, and thus may pose a risk to human health and to ecosystems. Its composition is high variable, including cyanide, fluoride and aluminum salts, which are highly toxic and environmental pollutants. This study evaluated the effect of SPL and its main components on root growth and the mitosis of Lactuca sativa, by investigating the mechanisms of cellular and chromosomal alterations with the aid of immunolocalization. To this end, newly emerged roots of L. sativa were exposed to SPL and its main components (solutions of cyanide, fluoride and aluminum) and to calcium chloride (control) for 48h. After this, root length was measured and cell cycle was examined by means of conventional cytogenetics and immunolocalization. Root growth was inhibited in the treatments with SPL and aluminum; chromosomal and nuclear alterations were observed in all treatments. The immunolocalization evidenced normal dividing cells with regular temporal and spatial distribution of histone H3 phosphorylation at serine 10 (H3S10ph). However, SPL and its main components inhibited the phosphorylation of histone H3 at serine 10, inactivated pericentromeric regions and affected the cohesion of sister chromatids, thus affecting the arrangement of chromosomes in the metaphase plate and separation of chromatids in anaphase. In addition, these substances induced breaks in pericentromeric regions, characterized as fragile sites.

  12. Impervious surface area as a predictor of the effects of urbanization on stream insect communities in Maine, USA.

    PubMed

    Morse, Chandler C; Huryn, Alexander D; Cronan, Christopher

    2003-11-01

    The influence of urbanization on stream insect communities was determined by comparing physical, chemical, and biological characteristics of streams draining 20 catchments with varying levels of urban land-cover in Maine (U.S.A). Percent total impervious surface area (PTIA), which was used to quantify urban land-use, ranged from approximately 1-31% among the study catchments. Taxonomic richness of stream insect communities showed an abrupt decline as PTIA increased above 6%. Streams draining catchments with PTIA < 6% had the highest levels of both total insect and EPT (Ephemeroptera + Plecoptera + Trichoptera) taxonomic richness. These streams contained insect communities with a total richness averaging 33 taxa in fall and 31 taxa in spring; EPT richness ranged from an average of 15 taxa in fall and 13 taxa in spring. In contrast, none of the streams draining catchments with 6-27% PTIA had a total richness > 18 taxa or an EPT richness > 6 taxa. Insect communities in streams with PTIA > 6% were characterized by the absence of pollution-intolerant taxa. The distribution of more pollution-tolerant taxa (e.g. Acerpenna (Ephemeroptera); Paracapnia, Allocapnia (Plecoptera); Optioservus, Stenelmis (Coleoptera); Hydropsyche, Cheumatopsvyche (Trichoptera)), however, showed little relation to PTIA. In contrast to the apparent threshold relationship between PTIA and insect taxonomic richness, both habitat quality and water quality tended to decline as linear functions of PTIA. Our results indicate that, in Maine, an abrupt change in stream insect community structure occurs at a PTIA above a threshold of approximately 6% of total catchment area. The measurement of PTIA may provide a valuable tool for predicting thresholds for adverse effects of urbanization on the health of headwater streams in Maine.

  13. Effects of experimental nitrogen and phosphorus addition on litter decomposition in an old-growth tropical forest.

    PubMed

    Chen, Hao; Dong, Shaofeng; Liu, Lei; Ma, Chuan; Zhang, Tao; Zhu, Xiaomin; Mo, Jiangming

    2013-01-01

    The responses of litter decomposition to nitrogen (N) and phosphorus (P) additions were examined in an old-growth tropical forest in southern China to test the following hypotheses: (1) N addition would decrease litter decomposition; (2) P addition would increase litter decomposition, and (3) P addition would mitigate the inhibitive effect of N addition. Two kinds of leaf litter, Schima superba Chardn. & Champ. (S.S.) and Castanopsis chinensis Hance (C.C.), were studied using the litterbag technique. Four treatments were conducted at the following levels: control, N-addition (150 kg N ha(-1) yr(-1)), P-addition (150 kg P ha(-1) yr(-1)) and NP-addition (150 kg N ha(-1) yr(-1) plus 150 kg P ha(-1) yr(-1)). While N addition significantly decreased the decomposition of both litters, P addition significantly inhibited decomposition of C.C., but did not affect the decomposition of S.S. The negative effect of N addition on litter decomposition might be related to the high N-saturation in this old-growth tropical forest; however, the negative effect of P addition might be due to the suppression of "microbial P mining". Significant interaction between N and P addition was found on litter decomposition, which was reflected by the less negative effect in NP-addition plots than those in N-addition plots. Our results suggest that P addition may also have negative effect on litter decomposition and that P addition would mitigate the negative effect of N deposition on litter decomposition in tropical forests.

  14. Effects of Experimental Nitrogen and Phosphorus Addition on Litter Decomposition in an Old-Growth Tropical Forest

    PubMed Central

    Chen, Hao; Dong, Shaofeng; Liu, Lei; Ma, Chuan; Zhang, Tao; Zhu, Xiaomin; Mo, Jiangming

    2013-01-01

    The responses of litter decomposition to nitrogen (N) and phosphorus (P) additions were examined in an old-growth tropical forest in southern China to test the following hypotheses: (1) N addition would decrease litter decomposition; (2) P addition would increase litter decomposition, and (3) P addition would mitigate the inhibitive effect of N addition. Two kinds of leaf litter, Schima superba Chardn. & Champ. (S.S.) and Castanopsis chinensis Hance (C.C.), were studied using the litterbag technique. Four treatments were conducted at the following levels: control, N-addition (150 kg N ha−1 yr−1), P-addition (150 kg P ha−1 yr−1) and NP-addition (150 kg N ha−1 yr−1 plus 150 kg P ha−1 yr−1). While N addition significantly decreased the decomposition of both litters, P addition significantly inhibited decomposition of C.C., but did not affect the decomposition of S.S. The negative effect of N addition on litter decomposition might be related to the high N-saturation in this old-growth tropical forest; however, the negative effect of P addition might be due to the suppression of “microbial P mining”. Significant interaction between N and P addition was found on litter decomposition, which was reflected by the less negative effect in NP-addition plots than those in N-addition plots. Our results suggest that P addition may also have negative effect on litter decomposition and that P addition would mitigate the negative effect of N deposition on litter decomposition in tropical forests. PMID:24391895

  15. Effects of h-BN addition on microstructures and mechanical properties of β-CaSiO3 bioceramics.

    PubMed

    Pan, Ying; Yao, Dongxu; Zuo, Kaihui; Xia, Yongfeng; Yin, Jinwei; Liang, Hanqin; Zeng, Yuping

    2016-09-01

    The main purpose of this study consists in investigating the effects of h-BN addition on the sinterability of β-CaSiO3 (β-CS) bioceramics. β-CS bioceramics with different contents of h-BN were prepared at the sintering temperature ranging from 800°C to 1100°C. The results showed that h-BN can be successfully used as sintering additive by being oxidized to form low melting point B2O3 related glassy phase and enhanced the flexural strength by the formation of rod-like β-CS grains. β-CS bioceramics with 1wt% h-BN sintered at 1000°C revealed flexural strength and fracture toughness of 182.2MPa and 2.4MPam(1/2) respectively, which were much higher than that of pure β-CS bioceramics (30.2MPa, 0.53MPam(1/2)) fabricated in the same processing condition.

  16. The effect of three different methods of adding O2 additive on O concentration of atmospheric pressure plasma jets (APPJs)

    NASA Astrophysics Data System (ADS)

    Yue, Y.; Xian, Y.; Pei, X.; Lu, X.

    2016-12-01

    In order to maximize the O concentration generated by the atmospheric pressure plasma jets (APPJs), several different methods of adding O2 additive to working gas have been proposed. However, it is not clear, which method is capable of generating the highest concentration of O atom. In this paper, the concentration of O atoms in an APPJs by adding O2 to (1) the working gas, to (2) the downstream inside the tube, and (3) to the shielding gas is investigated by two-photon absorption laser-induced fluorescence spectrometry. The results clearly demonstrate that the highest O density is achieved when 1.5% of O2 is added to the working gas rather than the other two methods. In other words, the most effective way to generate O atoms is by premixing O2 with the working gas. Further investigation suggests that O atoms are mainly generated around the electrode region, where the electric field is highest. In addition, when O2 is added to the working gas, if in the meantime extra O2 is added to the downstream inside the tube, a significant decrease of O density is observed.

  17. Effects of an additional basketball and volleyball program on motor abilities of fifth grade elementary school students.

    PubMed

    Selmanović, Aleksandar; Milanović, Dragan; Custonja, Zrinko

    2013-06-01

    The aim was to evaluate the transformational effects of an additional weekly PE session based on team sports (basketball and volleyball) on students' motor status. The research was conducted on a sample of 125 eleven-year-old boys divided into three groups (two experimental and one control) which were examined by 12 motor tests at the beginning and at the end of the 9-month period. The tests included evaluation of explosive power dynamic and static strength endurance, co-ordination, flexibility and hand frequency motion. Although all three treatments together, complemented by the natural growth and developmental factors, induced significant quantitative changes, the results showed the highest motor improvements in the basketball experimental group, followed by the volleyball experimental group. While explosive power mainly contributed toward significant difference between the control and experimental groups in the final measurement, univarate test results also showed distinctive improvements in dynamic strength, hand frequency motion and various factors of co-ordination within experimental groups. The general conclusion points to the fact that even one additional PE session per week of the given program is sufficient to produce significant changes in motor abilities of elementary school fifth graders. Therefore the authors' support the legal provisions of mandatory implementation of extra-curricular forms of physical activity in elementary schools.

  18. Additive feeding inhibitory and aversive effects of naltrexone and exendin-4 combinations

    PubMed Central

    Liang, N-C; Bello, NT; Moran, TH

    2012-01-01

    Objective One developing strategy for obesity treatment has been to use combinations of differently acting pharmacotherapies to improve weight loss with fewer adverse effects. The purpose of this study was to determine whether the combination of naltrexone, an opioid antagonist acting on the reward system, and exendin-4, a glucagon-like peptide 1 (GLP-1) agonist, acting on satiety signaling, would produce larger reductions in food intake than either alone in rats. Because the anorectic potencies of both compounds have been associated with nausea and malaise, the influence of these drug combinations on the acquisition of a conditioned taste aversion (CTA) was also determined. Methods In Experiment 1, the acute anorectic effects of naltrexone (0.32–3.2 mg/kg; IP) and exendin-4 (1–10 µg/kg; IP) were assessed alone or in combination. Combinational doses were further investigated by the repeated daily administration of 1 mg/kg naltrexone + 3.2 µg/kg exendin-4 for 4 days. In Experiment 2, both compounds alone or in combination were used as unconditioned stimuli in a series of CTA tests. Results Naltrexone and exendin-4, alone or in combination, suppressed food intake in a dose dependent fashion, and the interaction on food intake between naltrexone and exendin-4 was additive. In the CTA paradigm, naltrexone (1 mg/Kg) alone did not support acquisition, whereas a CTA was evident with doses of Ex-4 (1 or 3.2 µg/Kg). Combinations of naltrexone and exendin-4 also resulted in a more rapid and robust acquisition of a CTA. Conclusion Given that the Nal and Ex-4 combination produces additive effects on not only food intake reduction but also food aversion learning, this specific drug combination does not have the benefit of minimizing the adverse effects associated with each individual drug. These data suggest that it is necessary to evaluate both the positive and adverse effects at early stages of combinational drug development. PMID:22310470

  19. Effect of Addition of Fentanyl and Clonidine to Local Anesthetic Solution in Peribulbar Block

    PubMed Central

    Nehra, Poonam; Oza, Vrinda; Parmar, Vandana; Fumakiya, Pooja

    2017-01-01

    Objective: To compare the effect of addition of fentanyl and clonidine as adjuvants to bupivacaine and lignocaine in peribulbar block. Methods: The study was conducted on 105 adult patients of either sex, of ASA grade I and II undergoing ophthalmic surgeries. Patients were randomly divided into 3 groups of 35 each. All the patients were given peribulbuar block with 5ml lignocaine 2% +3 ml bupivacaine 0.5% +1 ml hyaluronidase (250 IU). In addition to this 1 ml normal saline was added to Group S, 25 μg fentanyl to Group F and 25 μg clonidine to Group C. Onset and duration of globe and lid akinesia, duration of sensory blockage and analgesia, hemodynamic parameters, number of rescue analgesic and visual analogue score were recorded. Results: The mean time of onset of globe and lid akinesia was significantly faster in group F and group C compared to group S, mean duration of globe and lid akinesia was longer in Group F (207.71 + 13.54 and 143.14 + 7.86 min) and group C (213.52 + 14.52 and 162.06 + 17.1 min) compared to group S (117.78 + 10.42 and 87.64 + 9.76 min). The mean duration of analgesia was significantly longer in group F (217.71 + 12.67) and C (258.82 + 14.50 min) as compared to group S (131.39 + 9.63 min). Conclusion: Addition of fentanyl or clonidine as adjuvant to local anaesthetic in peribulbar block provides faster onset and prolonged analgesia compared to local anaesthetic alone.

  20. Effects of ethanol addition on micellar solubilization and plume migration during surfactant enhanced recovery of tetrachloroethene

    NASA Astrophysics Data System (ADS)

    Taylor, Tammy P.; Rathfelder, Klaus M.; Pennell, Kurt D.; Abriola, Linda M.

    2004-03-01

    Alcohol addition has been suggested for use in combination with surfactant flushing to enhance solubilization kinetics and permit density control of dense non-aqueous phase liquid (DNAPL)-laden surfactant plumes. This study examined the effects of adding ethanol (EtOH) to a 4% Tween 80 (polyoxyethylene (20) sorbitan monooleate) solution used to flush tetrachloroethene (PCE)-contaminated porous media. The influence of EtOH concentration, subsurface layering and scale on flushing solution delivery and PCE recovery was investigated through a combination of experimental and mathematical modeling studies. Results of batch experiments demonstrated that the addition of 2.5%, 5% and 10% (wt.) EtOH incrementally increased the PCE solubilization capacity and viscosity of the surfactant solution, while reducing solution density from 1.002 to 0.986 g/cm 3. Effluent concentration data obtained from one-dimensional (1-D) column experiments were used to characterize rate-limited micellar solubilization of residual PCE, which was strongly dependent upon flow velocity and weakly dependent upon EtOH concentration. Two-dimensional (2-D) box studies illustrated that minor differences (0.008 g/cm 3) between flushing and resident solution density can strongly influence surfactant front propagation. A two-dimensional multiphase simulator, MISER, was used to model the influence of EtOH composition on the aqueous flow field and PCE mass recovery. The ability of the numerical simulator to predict effluent concentrations and front propagation was demonstrated for both 1-D columns and 2-D boxes flushed with EtOH-amended Tween 80 solutions. Results of this study quantify the potential influence of alcohol addition on surfactant solution properties and solubilization capacity, and demonstrate the importance of considering small density variations in remedial design.

  1. The Effect of Cerium Oxide Addition on the Properties and Behavior of Y-TZP

    PubMed Central

    Ragurajan, D.; Satgunam, M.; Golieskardi, M.

    2014-01-01

    The effects of CeO2 addition on the sintering behavior and mechanical properties of Y-TZP have been investigated over a wide sintering regime by pressureless sintering. It has been revealed that small additions of CeO2 (0.3–1.0 wt%) to Y-TZP were beneficial in enhancing the mechanical properties and hydrothermal ageing resistance of Y-TZP. Sintered samples were used to evaluate the bulk density, Vickers's hardness, Young's modulus, and fracture toughness of the material. CeO2 doped Y-TZPs were sintered at relatively low temperatures (1250°C and 1350°C) retaining high bulk density (>97% of theoretical density) and high Young's modulus (>200 GPa) without sacrificing tetragonal phase stability. The optimum level of dopant was found to be at 0.5 wt% for sintering between 1250°C and 1450°C using the standard 2 h holding time cycle, with sintered body exhibiting excellent combination of properties when compared to the undoped ceramics. In this experiment, the addition of 0.5 wt% recorded a bulk density reading of 5.9 g/cm3, Vickers hardness value of 13.2 GPa, Young's modulus value of 211 GPa, and fracture toughness of 6.4 MPam1/2, respectively, in a temperature range of 1400–1450°C. PMID:27437471

  2. Effect of crystals and fibrous network polymer additives on cellular morphology of microcellular foams

    NASA Astrophysics Data System (ADS)

    Miyamoto, Ryoma; Utano, Tatsumi; Yasuhara, Shunya; Ishihara, Shota; Ohshima, Masahiro

    2015-05-01

    In this study, the core-back foam injection molding was used for preparing microcelluar polypropylene (PP) foam with either a 1,3:2,4 bis-O-(4-methylbenzylidene)-D-sorbitol gelling agent (Gel-all MD) or a fibros network polymer additive (Metablen 3000). Both agent and addiive could effectively control the celluar morphology in foams but somehow different ways. In course of cooling the polymer with Gel-all MD in the mold caity, the agent enhanced the crystal nucleation and resulted in the large number of small crystals. The crystals acted as effective bubble nucleation agent in foaming process. Thus, the agent reduced the cell size and increased the cell density, drastically. Furthermore, the small crystals provided an inhomogenuity to the expanding cell wall and produced the high open cell content with nano-scale fibril structure. Gell-all as well as Metablene 3000 formed a gel-like fibrous network in melt. The network increased the elongational viscosity and tended to prevent the cell wall from breaking up. The foaming temperature window was widened by the presence of the network. Especially, the temperature window where the macro-fibrous structure was formed was expanded to the higher temperature. The effects of crystal nucleating agent and PTFE on crystals' size and number, viscoelsticity, rheological propreties of PP and cellular morphology were compared and thorougly investigated.

  3. Effects of pulverized coal fly-ash addition as a wet-end filler in papermaking

    SciTech Connect

    Sinha, A.S.K.

    2008-09-15

    This experimental study is based on the innovative idea of using pulverized coal fly ash as a wet-end filler in papermaking. This is the first evaluation of the possible use of fly ash in the paper industry. Coal-based thermal power plants throughout the world are generating fly ash as a solid waste product. The constituents of fly ash can be used effectively in papermaking. Fly ash has a wide variation in particle size, which ranges from a few micrometers to one hundred micrometers. Fly ash acts as an inert material in acidic, neutral, and alkaline papermaking processes. Its physical properties such as bulk density (800-980 kg/m{sup 3}), porosity (45%-57%), and surface area (0.138-2.3076 m{sup 2}/g) make it suitable for use as a paper filler. Fly ash obtained from thermal power plants using pulverized coal was fractionated by a vibratory-sieve stack. The fine fraction with a particle size below 38 micrometers was used to study its effect on the important mechanical-strength and optical properties of paper. The effects of fly-ash addition on these properties were compared with those of kaolin clay. Paper opacity was found to be much higher with fly ash as a filler, whereas brightness decreased as the filler percentage increased Mechanical strength properties of the paper samples with fly ash as filler were superior to those with kaolin clay.

  4. Additive concentration effects on dicalcium phosphate dihydrate cements prepared using monocalcium phosphate monohydrate and hydroxyapatite.

    PubMed

    Santa Cruz Chavez, Grace; Alge, Daniel L; Chu, Tien-Min Gabriel

    2011-12-01

    In our previous study, we investigated the setting time, mechanical properties and microstructure of dicalcium phosphate dihydrate cements prepared using monocalcium phosphate monohydrate (MCPM) and hydroxyapatite (HA). Despite the use of sodium citrate as a setting regulator, setting occurs rapidly in the MCPM/HA system and further studies on other retardants are needed. In the present study, sodium pyrophosphate and sulfuric acid were tested to evaluate their effectiveness in maintaining workability of the cement paste. MCPM/HA cements at a powder to liquid ratio of 1.0 with sodium pyrophosphate and sulfuric acid at 10, 25, 50, 75 and 100 mM were manufactured and studied based on their setting time, mechanical and porosity properties, phase composition, and microstructure. These measurements were compared to our previous data using sodium citrate. The results showed that the additives have a dose-dependent effect on the setting time. Their order of efficiency is sodium pyrophosphate > sodium citrate > sulfuric acid. However, the sulfuric acid group exhibited the highest compressive strength (CS) compared to the other groups. A lack of correlation between the CS and the porosity of the cements suggested that a mechanism other than porosity reduction was responsible for the CS increase. Since x-ray diffraction analysis did not indicate an effect on composition, explanations based on calcium sulfate dihydrate formation and changes in microstructure were proposed based on scanning electron micrograph observations.

  5. The effect of W and N addition on the mechanical properties of 10Cr steels

    NASA Astrophysics Data System (ADS)

    Kim, Sung Ho; Song, B. J.; Ryu, Woo Seog

    2001-07-01

    The effect of W and N on the creep properties and microstructural degradation in 10Cr steels was studied. Creep testing was performed to determine the creep rupture strength and minimum creep rate. Transmission electron microscopy was used to observe the microstructural degradation during the creep deformation. W and N which were added to the 10Cr steel increased the creep rupture strength and decreased the minimum creep rate. As W and N were added, the thermal stability of the subgrain and carbide was improved, thus the growth of the subgrain and carbide during creep deformation was restricted. In W added steel, the Laves phase played an important role in increasing creep rupture strength. But the impact toughness was rapidly degraded by the addition of W after aging at 600°C for 5000 hours. So one must evaluate more accurately the effect of the Laves phase on long term creep and impact properties. In N added steel, V(C, N) was precipitated in the lath boundary and within the lath. The size of the precipitates was 20-50 nm. The increase of creep rupture strength in N added steel may be due to the precipitate of the V(C, N). Future tests are required to clarify the effect of N on creep and impact properties.

  6. Additive and interactive effects of plant genotypic diversity on arthropod communities and plant fitness.

    PubMed

    Johnson, Marc T J; Lajeunesse, Marc J; Agrawal, Anurag A

    2006-01-01

    Recent research suggests that genetic diversity in plant populations can shape the diversity and abundance of consumer communities. We tested this hypothesis in a field experiment by manipulating patches of Evening Primrose (Oenothera biennis) to contain one, four or eight plant genotypes. We then surveyed 92 species of naturally colonizing arthropods. Genetically diverse plant patches had 18% more arthropod species, and a greater abundance of omnivorous and predacious arthropods, but not herbivores, compared with monocultures. The effects of genotypic diversity on arthropod communities were due to a combination of interactive and additive effects among genotypes within genetically diverse patches. Greater genetic diversity also led to a selective feedback, as mean genotype fitness was 27% higher in diverse patches than in monocultures. A comparison between our results and the literature reveals that genetic diversity and species diversity can have similar qualitative and quantitative effects on arthropod communities. Our findings also illustrate the benefit of preserving genetic variation to conserve species diversity and interactions within multitrophic communities.