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  1. Significant change of local atomic configurations at surface of reduced activation Eurofer steels induced by hydrogenation treatments

    Science.gov (United States)

    Greculeasa, S. G.; Palade, P.; Schinteie, G.; Kuncser, A.; Stanciu, A.; Lungu, G. A.; Porosnicu, C.; Lungu, C. P.; Kuncser, V.

    2017-04-01

    Reduced-activation steels such as Eurofer alloys are candidates for supporting plasma facing components in tokamak-like nuclear fusion reactors. In order to investigate the impact of hydrogen/deuterium insertion in their crystalline lattice, annealing treatments in hydrogen atmosphere have been applied on Eurofer slabs. The resulting samples have been analyzed with respect to local structure and atomic configuration both before and after successive annealing treatments, by X-ray diffractometry (XRD), scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS), X-ray photoelectron spectroscopy (XPS) and conversion electron Mössbauer spectroscopy (CEMS). The corroborated data point out for a bcc type structure of the non-hydrogenated alloy, with an average alloy composition approaching Fe0.9Cr0.1 along a depth of about 100 nm. EDS elemental maps do not indicate surface inhomogeneities in concentration whereas the Mössbauer spectra prove significant deviations from a homogeneous alloying. The hydrogenation increases the expulsion of the Cr atoms toward the surface layer and decreases their oxidation, with considerable influence on the surface properties of the steel. The hydrogenation treatment is therefore proposed as a potential alternative for a convenient engineering of the surface of different Fe-Cr based alloys.

  2. Surface characterization based upon significant topographic features

    Energy Technology Data Exchange (ETDEWEB)

    Blanc, J; Grime, D; Blateyron, F, E-mail: fblateyron@digitalsurf.fr [Digital Surf, 16 rue Lavoisier, F-25000 Besancon (France)

    2011-08-19

    Watershed segmentation and Wolf pruning, as defined in ISO 25178-2, allow the detection of significant features on surfaces and their characterization in terms of dimension, area, volume, curvature, shape or morphology. These new tools provide a robust way to specify functional surfaces.

  3. The oxidation capacity of Mn3O4 nanoparticles is significantly enhanced by anchoring them onto reduced graphene oxide to facilitate regeneration of surface-associated Mn(III).

    Science.gov (United States)

    Duan, Lin; Wang, Zhongyuan; Hou, Yan; Wang, Zepeng; Gao, Guandao; Chen, Wei; Alvarez, Pedro J J

    2016-10-15

    Metal oxides are often anchored to graphene materials to achieve greater contaminant removal efficiency. To date, the enhanced performance has mainly been attributed to the role of graphene materials as a conductor for electron transfer. Herein, we report a new mechanism via which graphene materials enhance oxidation of organic contaminants by metal oxides. Specifically, Mn3O4-rGO nanocomposites (Mn3O4 nanoparticles anchored to reduced graphene oxide (rGO) nanosheets) enhanced oxidation of 1-naphthylamine (used here as a reaction probe) compared to bare Mn3O4. Spectroscopic analyses (X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy) show that the rGO component of Mn3O4-rGO was further reduced during the oxidation of 1-naphthylamine, although rGO reduction was not the result of direct interaction with 1-naphthylamine. We postulate that rGO improved the oxidation efficiency of anchored Mn3O4 by re-oxidizing Mn(II) formed from the reaction between Mn3O4 and 1-naphthylamine, thereby regenerating the surface-associated oxidant Mn(III). The proposed role of rGO was verified by separate experiments demonstrating its ability to oxidize dissolved Mn(II) to Mn(III), which subsequently can oxidize 1-naphthylamine. The role of dissolved oxygen in re-oxidizing Mn(II) was ruled out by anoxic (N2-purged) control experiments showing similar results as O2-sparged tests. Opposite pH effects on the oxidation efficiency of Mn3O4-rGO versus bare Mn3O4 were also observed, corroborating the proposed mechanism because higher pH facilitates oxidation of surface-associated Mn(II) even though it lowers the oxidation potential of Mn3O4. Overall, these findings may guide the development of novel metal oxide-graphene nanocomposites for contaminant removal. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. PA positioning significantly reduces testicular dose during sacroiliac joint radiography

    Energy Technology Data Exchange (ETDEWEB)

    Mekis, Nejc [Faculty of Health Sciences, University of Ljubljana (Slovenia); Mc Entee, Mark F., E-mail: mark.mcentee@ucd.i [School of Medicine and Medical Science, University College Dublin 4 (Ireland); Stegnar, Peter [Jozef Stefan International Postgraduate School, Ljubljana (Slovenia)

    2010-11-15

    Radiation dose to the testes in the antero-posterior (AP) and postero-anterior (PA) projection of the sacroiliac joint (SIJ) was measured with and without a scrotal shield. Entrance surface dose, the dose received by the testicles and the dose area product (DAP) was used. DAP measurements revealed the dose received by the phantom in the PA position is 12.6% lower than the AP (p {<=} 0.009) with no statistically significant reduction in image quality (p {<=} 0.483). The dose received by the testes in the PA projection in SIJ imaging is 93.1% lower than the AP projection when not using protection (p {<=} 0.020) and 94.9% lower with protection (p {<=} 0.019). The dose received by the testicles was not changed by the use of a scrotal shield in the AP position (p {<=} 0.559); but was lowered by its use in the PA (p {<=} 0.058). Use of the PA projection in SIJ imaging significantly lowers, the dose received by the testes compared to the AP projection without significant loss of image quality.

  5. Swimming Motility Reduces Deposition to Silica Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Nanxi [Univ. of Illinois, Urbana-Champaign, IL (United States); Massoudieh, Arash [The Catholic Univ. of America, Washington, DC (United States); Liang, Xiaomeng [The Catholic Univ. of America, Washington, DC (United States); Hu, Dehong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kamai, Tamir [Agricultural Research Organization, Bet Dagan (Israel); Ginn, Timothy R. [Univ. of California, Davis, CA (United States); Zilles, Julie L. [Univ. of Illinois, Urbana-Champaign, IL (United States); Nguyen, Thanh H. [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2015-01-01

    The role of swimming motility on bacterial transport and fate in porous media was evaluated. We present microscopic evidence showing that strong swimming motility reduces attachment of Azotobacter vinelandii cells to silica surfaces. Applying global and cluster statistical analyses to microscopic videos taken under non-flow conditions, wild type, flagellated A. vinelandii strain DJ showed strong swimming ability with an average speed of 13.1 μm/s, DJ77 showed impaired swimming averaged at 8.7 μm/s, and both the non-flagellated JZ52 and chemically treated DJ cells were non-motile. Quantitative analyses of trajectories observed at different distances above the collector of a radial stagnation point flow cell (RSPF) revealed that both swimming and non-swimming cells moved with the flow when at a distance of at least 20 μm from the collector surface. Near the surface, DJ cells showed both horizontal and vertical movement diverging them from reaching surfaces, while chemically treated DJ cells moved with the flow to reach surfaces, suggesting that strong swimming reduced attachment. In agreement with the RSPF results, the deposition rates obtained for two-dimensional multiple-collector micromodels were also lowest for DJ, while DJ77 and JZ52 showed similar values. Strong swimming specifically reduced deposition on the upstream surfaces of the micromodel collectors.

  6. Mitochondrial Polymorphisms Significantly Reduce the Risk of Parkinson Disease

    Science.gov (United States)

    van der Walt, Joelle M.; Nicodemus, Kristin K.; Martin, Eden R.; Scott, William K.; Nance, Martha A.; Watts, Ray L.; Hubble, Jean P.; Haines, Jonathan L.; Koller, William C.; Lyons, Kelly; Pahwa, Rajesh; Stern, Matthew B.; Colcher, Amy; Hiner, Bradley C.; Jankovic, Joseph; Ondo, William G.; Allen Jr., Fred H.; Goetz, Christopher G.; Small, Gary W.; Mastaglia, Frank; Stajich, Jeffrey M.; McLaurin, Adam C.; Middleton, Lefkos T.; Scott, Burton L.; Schmechel, Donald E.; Pericak-Vance, Margaret A.; Vance, Jeffery M.

    2003-01-01

    Mitochondrial (mt) impairment, particularly within complex I of the electron transport system, has been implicated in the pathogenesis of Parkinson disease (PD). More than half of mitochondrially encoded polypeptides form part of the reduced nicotinamide adenine dinucleotide dehydrogenase (NADH) complex I enzyme. To test the hypothesis that mtDNA variation contributes to PD expression, we genotyped 10 single-nucleotide polymorphisms (SNPs) that define the European mtDNA haplogroups in 609 white patients with PD and 340 unaffected white control subjects. Overall, individuals classified as haplogroup J (odds ratio [OR] 0.55; 95% confidence interval [CI] 0.34–0.91; P=.02) or K (OR 0.52; 95% CI 0.30–0.90; P=.02) demonstrated a significant decrease in risk of PD versus individuals carrying the most common haplogroup, H. Furthermore, a specific SNP that defines these two haplogroups, 10398G, is strongly associated with this protective effect (OR 0.53; 95% CI 0.39–0.73; P=.0001). SNP 10398G causes a nonconservative amino acid change from threonine to alanine within the NADH dehydrogenase 3 (ND3) of complex I. After stratification by sex, this decrease in risk appeared stronger in women than in men (OR 0.43; 95% CI 0.27–0.71; P=.0009). In addition, SNP 9055A of ATP6 demonstrated a protective effect for women (OR 0.45; 95% CI 0.22–0.93; P=.03). Our results suggest that ND3 is an important factor in PD susceptibility among white individuals and could help explain the role of complex I in PD expression. PMID:12618962

  7. Solid Surface Combustion at Reduced Gravity

    Science.gov (United States)

    Altenkirch, R. A.

    1985-01-01

    The spread of a flame in the gas over the surface of a solid combustible involves in an essential way the transfer of heat from the flame to the solid fuel immediately ahead of it. This heat transfer is affected by the character of the gas phase flame, and so the phenomenon of flame spreading under reduced gravity, in which the flow is generated by gasification of the solid combustible, is apt to be different from what occurs under the Earth's normal gravitational acceleration where the flow is largely buoyancy driven. An experiment is being designed for the Middeck of the Space Shuttle to aid us in understanding the process of flame spreading in the absence of a buoyancy driven flow. A chamber approximately 0.35 cu.m. in volume is to contain either a thin sample of a cellulosic material or a thick sample of polymethyl-methacrylate and an oxidizing environment of O2 and N2. Samples will be ignited at one end, and the ensuing flame spread will be filmed. The spread rate can be determined from the films, and surface and gas-phase temperatures just above the surface will also be recorded. These data will help to clarify the mechanism of forward heat transfer in the low gravity flames.

  8. Tadalafil significantly reduces ischemia reperfusion injury in skin island flaps

    Directory of Open Access Journals (Sweden)

    Oguz Kayiran

    2013-01-01

    Full Text Available Introduction: Numerous pharmacological agents have been used to enhance the viability of flaps. Ischemia reperfusion (I/R injury is an unwanted, sometimes devastating complication in reconstructive microsurgery. Tadalafil, a specific inhibitor of phosphodiesterase type 5 is mainly used for erectile dysfunction, and acts on vascular smooth muscles, platelets and leukocytes. Herein, the protective and therapeutical effect of tadalafil in I/R injury in rat skin flap model is evaluated. Materials and Methods: Sixty epigastric island flaps were used to create I/R model in 60 Wistar rats (non-ischemic group, ischemic group, medication group. Biochemical markers including total nitrite, malondialdehyde (MDA and myeloperoxidase (MPO were analysed. Necrosis rates were calculated and histopathologic evaluation was carried out. Results: MDA, MPO and total nitrite values were found elevated in the ischemic group, however there was an evident drop in the medication group. Histological results revealed that early inflammatory findings (oedema, neutrophil infiltration, necrosis rate were observed lower with tadalafil administration. Moreover, statistical significance (P < 0.05 was recorded. Conclusions: We conclude that tadalafil has beneficial effects on epigastric island flaps against I/R injury.

  9. Colchicine Significantly Reduces Incident Cancer in Gout Male Patients

    Science.gov (United States)

    Kuo, Ming-Chun; Chang, Shun-Jen; Hsieh, Ming-Chia

    2015-01-01

    Abstract Patients with gout are more likely to develop most cancers than subjects without gout. Colchicine has been used for the treatment and prevention of gouty arthritis and has been reported to have an anticancer effect in vitro. However, to date no study has evaluated the relationship between colchicine use and incident cancers in patients with gout. This study enrolled male patients with gout identified in Taiwan's National Health Insurance Database for the years 1998 to 2011. Each gout patient was matched with 4 male controls by age and by month and year of first diagnosis, and was followed up until 2011. The study excluded those who were diagnosed with diabetes or any type of cancer within the year following enrollment. We calculated hazard ratio (HR), aged-adjusted standardized incidence ratio, and incidence of 1000 person-years analyses to evaluate cancer risk. A total of 24,050 male patients with gout and 76,129 male nongout controls were included. Patients with gout had a higher rate of incident all-cause cancers than controls (6.68% vs 6.43%, P = 0.006). A total of 13,679 patients with gout were defined as having been ever-users of colchicine and 10,371 patients with gout were defined as being never-users of colchicine. Ever-users of colchicine had a significantly lower HR of incident all-cause cancers than never-users of colchicine after adjustment for age (HR = 0.85, 95% CI = 0.77–0.94; P = 0.001). In conclusion, colchicine use was associated with a decreased risk of incident all-cause cancers in male Taiwanese patients with gout. PMID:26683907

  10. Genetic variation and significance of hepatitis B surface antigen

    Directory of Open Access Journals (Sweden)

    ZHANG Zhenhua

    2013-11-01

    Full Text Available Hepatitis B virus (HBV is prone to genetic variation because there is reverse transcription in the process of HBV replication. The gene mutation of hepatitis B surface antigen may affect clinical diagnosis of HBV infection, viral replication, and vaccine effect. The current research and existing problems are discussed from the following aspects: the mechanism and biological and clinical significance of S gene mutation. Most previous studies focused on S gene alone, so S gene should be considered as part of HBV DNA in the future research on S gene mutation.

  11. Reducing roll motion by passive free surface tanks

    DEFF Research Database (Denmark)

    Nielsen, Ulrik Dam; Nielsen, Christian S.

    2014-01-01

    Roll stabilisation of motorised vessels plays an important part in reducing passenger discomfort and increasing safety and cargo capacity. Passive free surface tanks are considered a low-cost stabilising method, which is efficient at all speeds without increasing hull resistance. In this study......, a mathematical model for evaluating the performance of a passive free surface tank is established. This is done by coupling a roll model to a fluid flow model. As a numerical example, the seakeeping abilities of a container vessel are evaluated. The necessary methods for performing the simulation are presented...... and the design of a free surface tank is explained. The effects of the passive free surface tank are evaluated and a significant damping effect is observed, particularly in cases with resonant roll....

  12. Nitrate reducing activity pervades surface waters during upwelling.

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, S.O.; Halarnekar, R.; Malik, A.; Vijayan, V.; Varik, S.; RituKumari; Jineesh V.K.; Gauns, M.U.; Nair, S.; LokaBharathi, P.A.

    Nitrate reducing activity (NRA) is known to be mediated by microaerophilic to anaerobic bacteria and generally occurs in the sub-surface waters. However, we hypothesize that NRA could become prominent in the surface waters during upwelling. Hence...

  13. Nanotexturing of surfaces to reduce melting point.

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Ernest J.; Zubia, David (University of Texas at El Paso El Paso, TX); Mireles, Jose (Universidad Aut%C3%94onoma de Ciudad Ju%C3%94arez Ciudad Ju%C3%94arez, Mexico); Marquez, Noel (University of Texas at El Paso El Paso, TX); Quinones, Stella (University of Texas at El Paso El Paso, TX)

    2011-11-01

    This investigation examined the use of nano-patterned structures on Silicon-on-Insulator (SOI) material to reduce the bulk material melting point (1414 C). It has been found that sharp-tipped and other similar structures have a propensity to move to the lower energy states of spherical structures and as a result exhibit lower melting points than the bulk material. Such a reduction of the melting point would offer a number of interesting opportunities for bonding in microsystems packaging applications. Nano patterning process capabilities were developed to create the required structures for the investigation. One of the technical challenges of the project was understanding and creating the specialized conditions required to observe the melting and reshaping phenomena. Through systematic experimentation and review of the literature these conditions were determined and used to conduct phase change experiments. Melting temperatures as low as 1030 C were observed.

  14. Biological and Chemical Significance of Surface Microlayers in Aquatic Ecosystems

    Science.gov (United States)

    Parker, B.; Barsom, G.

    1970-01-01

    Reviews methods of study, chemical composition, physical properties and ecology of surface microlayers in marine and fresh water habitats. Relates to problems of air and water pollution. Suggests areas for further research. (EB)

  15. Significantly improved photocurrent response of ZnS-reduced graphene oxide composites

    Energy Technology Data Exchange (ETDEWEB)

    Sookhakian, M., E-mail: m.sokhakian@gmail.com [Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Amin, Y.M. [Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Zakaria, R. [Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Photonics Research Centre, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Basirun, W.J. [Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Institute of Nanotechnology & Catalysis Research (NanoCat), University Malaya, Kuala Lumpur 50603 (Malaysia); Mahmoudian, M.R. [Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia); Nasiri-Tabrizi, B.; Baradaran, S. [Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603 (Malaysia); Azarang, Majid [Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia)

    2015-05-25

    Highlights: • ZnS/reduced graphene oxide nanoparticles by hydrothermal method. • ZnS nanoparticles in a gelatin medium without agglomeration. • Support of ZnS shows efficient photocurrent response. • The fabricated solar cell electrode improved in the presence of reduced graphene oxide. - Abstract: ZnS-nanoparticles (NPs) reduced graphene oxide (rGO) composites with a high degree of crystallinity and high dispersity were successfully synthesized via a facile solvothermal method in the gelatin medium, during which the formation of ZnS NPs, reduction of graphene oxide and loading of ZnS NPs into the rGO surface occur simultaneously. Gelatin, as a natural capping agent, plays a significant role in controlling the degree of dispersion and coverage of ZnS NPs. The effect of rGO on the crystalline structure and optical properties of ZnS NPs were determined via X-ray diffraction, UV–visible diffused reflectance spectroscopy and photoluminescence spectroscopy. The ZnS–rGO composites exhibit excellent potential for photocurrent generation compared with pure ZnS NPs under visible light irradiation, provided that efficient photoinduced charge separation and transportation can be achieved at the interface. The maximum photocurrent response was obtained for ZnS–rGO composite with a 3% mass fraction of rGO, which is 2 times that achieved on pure ZnS NPs.

  16. Reducing Sliding Friction with Liquid-Impregnated Surfaces

    Science.gov (United States)

    Habibi, Mohammad; Collier, C. Patrick; Boreyko, Jonathan; Nature Inspired Fluids; Interfaces Team; CenterNanophase Materials Sciences Team

    2015-11-01

    Liquid-impregnated surfaces are fabricated by infusing a lubricating liquid into the micro/nano roughness of a textured substrate, such that the surface is slippery for any deposited liquid immiscible with the lubricant. To date, liquid-impregnated surfaces have almost exclusively focused on repelling liquids by minimizing the contact angle hysteresis. Here, we demonstrate that liquid-impregnated surfaces are also capable of reducing sliding friction for solid objects. Ordered arrays of silicon micropillars were infused with lubricating liquids varying in viscosity by two orders of magnitude. Five test surfaces were used: two different micropillared surfaces with and without liquid infusion and a smooth, dry control surface. The static and kinetic coefficients of friction were measured using a polished aluminum cube as the sliding object. Compared to the smooth control surface, the sliding friction was reduced by at least a factor of two on the liquid-impregnated surfaces.

  17. The significant surface-water connectivity of "geographically isolated wetlands"

    Science.gov (United States)

    Calhoun, Aram J. K.; Mushet, David M.; Alexander, Laurie C.; DeKeyser, Edward S.; Fowler, Laurie; Lane, Charles R.; Lang, Megan W.; Rains, Mark C.; Richter, Stephen; Walls, Susan

    2017-01-01

    We evaluated the current literature, coupled with our collective research expertise, on surface-water connectivity of wetlands considered to be “geographically isolated” (sensu Tiner Wetlands 23:494–516, 2003a) to critically assess the scientific foundation of grouping wetlands based on the singular condition of being surrounded by uplands. The most recent research on wetlands considered to be “geographically isolated” shows the difficulties in grouping an ecological resource that does not reliably indicate lack of surface water connectivity in order to meet legal, regulatory, or scientific needs. Additionally, the practice of identifying “geographically isolated wetlands” based on distance from a stream can result in gross overestimates of the number of wetlands lacking ecologically important surface-water connections. Our findings do not support use of the overly simplistic label of “geographically isolated wetlands”. Wetlands surrounded by uplands vary in function and surface-water connections based on wetland landscape setting, context, climate, and geographic region and should be evaluated as such. We found that the “geographically isolated” grouping does not reflect our understanding of the hydrologic variability of these wetlands and hence does not benefit conservation of the Nation’s diverse wetland resources. Therefore, we strongly discourage use of categorizations that provide overly simplistic views of surface-water connectivity of wetlands fully embedded in upland landscapes.

  18. Using lytic bacteriophages to eliminate or significantly reduce contamination of food by foodborne bacterial pathogens.

    Science.gov (United States)

    Sulakvelidze, Alexander

    2013-10-01

    Bacteriophages (also called 'phages') are viruses that kill bacteria. They are arguably the oldest (3 billion years old, by some estimates) and most ubiquitous (total number estimated to be 10(30) -10(32) ) known organisms on Earth. Phages play a key role in maintaining microbial balance in every ecosystem where bacteria exist, and they are part of the normal microflora of all fresh, unprocessed foods. Interest in various practical applications of bacteriophages has been gaining momentum recently, with perhaps the most attention focused on using them to improve food safety. That approach, called 'phage biocontrol', typically includes three main types of applications: (i) using phages to treat domesticated livestock in order to reduce their intestinal colonization with, and shedding of, specific bacterial pathogens; (ii) treatments for decontaminating inanimate surfaces in food-processing facilities and other food establishments, so that foods processed on those surfaces are not cross-contaminated with the targeted pathogens; and (iii) post-harvest treatments involving direct applications of phages onto the harvested foods. This mini-review primarily focuses on the last type of intervention, which has been gaining the most momentum recently. Indeed, the results of recent studies dealing with improving food safety, and several recent regulatory approvals of various commercial phage preparations developed for post-harvest food safety applications, strongly support the idea that lytic phages may provide a safe, environmentally-friendly, and effective approach for significantly reducing contamination of various foods with foodborne bacterial pathogens. However, some important technical and nontechnical problems may need to be addressed before phage biocontrol protocols can become an integral part of routine food safety intervention strategies implemented by food industries in the USA.

  19. Properties and significance of the surface dipole mode

    CERN Document Server

    Papakonstantinou, P

    2014-01-01

    A strong isoscalar dipole resonance is known to be excited in a variety of nuclei, including isospin symmetric ones, at approximately 6-7 MeV. A series of theoretical studies and accumulating experimental evidence support an interpretation of the above dipole resonance as an elementary surface vibration. Obviously, such a mode is potentially as interesting as any collective excitation for a variety of reasons. In addition, though, it is found to account for the observed isoscalar segment of pygmy dipole strength. As discussed here, this has important implications for pygmy-strength interpretations and searches for genuine neutron-skin oscillations.

  20. Significance of Polarization Charges and Isomagnetic Surface in Magnetohydrodynamics.

    Directory of Open Access Journals (Sweden)

    Zhu-Xing Liang

    Full Text Available From the frozen-in field lines concept, a highly conducting fluid can move freely along, but not traverse to, magnetic field lines. We discuss this topic and find that in the study of the frozen-in field lines concept, the effects of inductive and capacitive reactance have been omitted. When admitted, the relationships among the motional electromotive field, the induced electric field, the eddy electric current, and the magnetic field becomes clearer. We emphasize the importance of isomagnetic surfaces and polarization charges, and show analytically that whether a conducting fluid can freely traverse magnetic field lines or not depends solely on the magnetic gradient along the path of the fluid. If a fluid does not change its density distribution and shape (can be regarded as a quasi-rigid body and moves along isomagnetic surface, it can freely traverse magnetic field lines without any magnetic drag, no matter how strong the magnetic field is. Besides theoretical analysis, we also present experimental results to support our analysis. The main purpose of this work is to correct a fallacy among some astrophysicists.

  1. Significance of Polarization Charges and Isomagnetic Surface in Magnetohydrodynamics.

    Science.gov (United States)

    Liang, Zhu-Xing; Liang, Yi

    2015-01-01

    From the frozen-in field lines concept, a highly conducting fluid can move freely along, but not traverse to, magnetic field lines. We discuss this topic and find that in the study of the frozen-in field lines concept, the effects of inductive and capacitive reactance have been omitted. When admitted, the relationships among the motional electromotive field, the induced electric field, the eddy electric current, and the magnetic field becomes clearer. We emphasize the importance of isomagnetic surfaces and polarization charges, and show analytically that whether a conducting fluid can freely traverse magnetic field lines or not depends solely on the magnetic gradient along the path of the fluid. If a fluid does not change its density distribution and shape (can be regarded as a quasi-rigid body) and moves along isomagnetic surface, it can freely traverse magnetic field lines without any magnetic drag, no matter how strong the magnetic field is. Besides theoretical analysis, we also present experimental results to support our analysis. The main purpose of this work is to correct a fallacy among some astrophysicists.

  2. Correlation effects driven by reduced dimensionality in magnetic surface alloys

    Indian Academy of Sciences (India)

    U Manju

    2015-06-01

    The evolution of electronic properties and correlation effects in manganese-based two-dimensional magnetic surface alloys are discussed. Enhanced correlations resulting from the reduced dimensionality of the surface alloys lead to the modification of the core level and valence band electronic structures resulting in the appearance of distinct satellite features. Apart from this, surface alloying-induced strong modifications in the substrate surface states arising from charge reorganization and electron transfer to the surface states as well as band-gap openings are also discussed.

  3. Clinical significance of hepatitis B surface antigen mutants.

    Science.gov (United States)

    Coppola, Nicola; Onorato, Lorenzo; Minichini, Carmine; Di Caprio, Giovanni; Starace, Mario; Sagnelli, Caterina; Sagnelli, Evangelista

    2015-11-28

    Hepatitis B virus (HBV) infection is a major public health problem in many countries, with nearly 300 million people worldwide carrying HBV chronic infection and over 1 million deaths per year due to cirrhosis and liver cancer. Several hepatitis B surface antigen (HBsAg) mutations have been described, most frequently due to a single amino acid substitution and seldom to a nucleotide deletion. The majority of mutations are located in the S region, but they have also been found in the pre-S1 and pre-S2 regions. Single amino acid substitutions in the major hydrophilic region of HBsAg, called the "a" determinant, have been associated with immune escape and the consequent failure of HBV vaccination and HBsAg detection, whereas deletions in the pre-S1 or pre-S2 regions have been associated with the development of hepatocellular carcinoma. This review article will focus on the HBsAg mutants and their biological and clinical implications.

  4. Clinical significance of hepatitis B surface antigen mutants

    Institute of Scientific and Technical Information of China (English)

    Nicola; Coppola; Lorenzo; Onorato; Carmine; Minichini; Giovanni; Di; Caprio; Mario; Starace; Caterina; Sagnelli; Evangelista; Sagnelli

    2015-01-01

    Hepatitis B virus(HBV) infection is a major public health problem in many countries, with nearly 300 million people worldwide carrying HBV chronic infection and over 1 million deaths per year due to cirrhosis and liver cancer. Several hepatitis B surface antigen(HBs Ag) mutations have been described, most frequently due to a single amino acid substitution and seldom to a nucleotide deletion. The majority of mutations are located in the S region, but they have also been found in the pre-S1 and pre-S2 regions. Single amino acid substitutions in the major hydrophilic region of HBs Ag, called the "a" determinant, have been associated with immune escape and the consequent failure of HBV vaccination and HBs Ag detection, whereas deletions in the pre-S1 or pre-S2 regions have been associated with the development of hepatocellular carcinoma. This review article will focus on the HBs Ag mutants and their biological and clinical implications.

  5. Prognostic significance of cell surface phenotype in acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Shiek Aejaz Aziz

    2015-01-01

    Full Text Available Context: To find out the phenotypic character of lymphoblasts of acute lymphoblastic leukemia (ALL patients in our study cohort and their possible effect on the prognosis. Aims: To investigate the phenotype in ALL in our demographic population and to prognosticate various upfront current protocols employed in our hospital. Settings and Design: The study spanned over a period of 4 years with retrospective and prospective data of January 2008 through December 2011. Materials and Methods: 159 patients of all age groups were enrolled for the study, of which flow cytometry was done in 144 patients. Statistical Analysis Used: Analysis was done using the variables on SPSS (statistical package for social sciences software on computer. Survival curves were estimated by method of Kaplan-Meir. Results: Majority of the patients were of B-cell (68.1% and 30.6% patients were of T-cell lineage. Of these, 80.6% patients were having cALLa positivity. Complete remission (CR was achieved in 59.1%, 16.4% relapsed, and 20.1% patients died. Conclusions: Phenotyping has become an important and integral part of diagnosis, classification, management and prognosticating in ALL. B-cell has been found to have a better survival over T-cell lymphoblastic leukemia. cALLa antigen positivity has good impact in achieving CR in only B-cell lineage, myeloid coexpression has no significant effect on the outcome. BFM (Berlin-Frankfurt-Münster based protocols though showed a higher CR and survival vis-a-vis UKALL-XII. However, patients enrolled in former group being of low risk category and lesser in numbers cannot be compared statistically with a fair degree of confidence.

  6. Communication: Proper treatment of classically forbidden electronic transitions significantly improves detailed balance in surface hopping.

    Science.gov (United States)

    Sifain, Andrew E; Wang, Linjun; Prezhdo, Oleg V

    2016-06-01

    Surface hopping is the most popular method for nonadiabatic molecular dynamics. Many have reported that it does not rigorously attain detailed balance at thermal equilibrium, but does so approximately. We show that convergence to the Boltzmann populations is significantly improved when the nuclear velocity is reversed after a classically forbidden hop. The proposed prescription significantly reduces the total number of classically forbidden hops encountered along a trajectory, suggesting that some randomization in nuclear velocity is needed when classically forbidden hops constitute a large fraction of attempted hops. Our results are verified computationally using two- and three-level quantum subsystems, coupled to a classical bath undergoing Langevin dynamics.

  7. Utilization of UV Curing Technology to Significantly Reduce the Manufacturing Cost of LIB Electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Voelker, Gary [Miltec UV International, LLC, Stevensville, MD (United States); Arnold, John [Miltec UV International, LLC, Stevensville, MD (United States)

    2015-11-30

    Previously identified novel binders and associated UV curing technology have been shown to reduce the time required to apply and finish electrode coatings from tens of minutes to less than one second. This revolutionary approach can result in dramatic increases in process speeds, significantly reduced capital (a factor of 10 to 20) and operating costs, reduced energy requirements, and reduced environmental concerns and costs due to the virtual elimination of harmful volatile organic solvents and associated solvent dryers and recovery systems. The accumulated advantages of higher speed, lower capital and operating costs, reduced footprint, lack of VOC recovery, and reduced energy cost is a reduction of 90% in the manufacturing cost of cathodes. When commercialized, the resulting cost reduction in Lithium batteries will allow storage device manufacturers to expand their sales in the market and thereby accrue the energy savings of broader utilization of HEVs, PHEVs and EVs in the U.S., and a broad technology export market is also envisioned.

  8. Surface nanocrystallization of stainless steel for reduced biofilm adherence

    Energy Technology Data Exchange (ETDEWEB)

    Yu Bin; Li, D Y [Department of Biomedical Engineering, University of Alberta, Edmonton, AB (Canada); Davis, Elisabeth M; Irvin, Randall T [Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, T6G 2H7 (Canada); Hodges, Robert S [Department of Biochemistry and Molecular Genetics, University of Colorado Health Sciences Center at Fitzsimons, RC1 South Tower, Room 9121, PO Box 6511 MS 8101, Aurora, CO 80045 (United States)], E-mail: dongyang@ualberta.ca

    2008-08-20

    Stainless steel is one of the most common metallic biomedical materials. For medical applications, its resistance to the adherence of biofilms is of importance to the elimination or minimization of bacterial infections. In this study, we demonstrate the effectiveness of a process combining surface nanocrystallization and thermal oxidation (or a recovery heat treatment in air) for reducing the biofilm's adherence to stainless steel. During this treatment, a target surface was sandblasted and the resultant dislocation cells in the surface layer were turned into nanosized grains by a subsequent recovery treatment in air. This process generated a more protective oxide film that blocked the electron exchange or reduced the surface activity more effectively. As a result, the biofilm's adherence to the treated surface was markedly minimized. A synthetic peptide was utilized as a substitute of biofilms to evaluate the adhesion between a treated steel surface and biofilms using an atomic force microscope (AFM) through measuring the adhesive force between the target surface and a peptide-coated AFM tip. It was shown that the adhesive force decreased with a decrease in the grain size of the steel. The corresponding surface electron work function (EWF) of the steel was also measured, which showed a trend of variation in EWF with the grain size, consistent with corresponding changes in the adhesive force.

  9. Pegasus project. DLC coating and low viscosity oil reduce energy losses significantly

    Energy Technology Data Exchange (ETDEWEB)

    Doerwald, Dave; Jacobs, Ruud [Hauzer Techno Coating (Netherlands). Tribological Coatings

    2012-03-15

    Pegasus, the flying horse from Greek mythology, is a suitable name for the research project initiated by a German automotive OEM with participation of Hauzer Techno Coating and several automotive suppliers. It will enable future automotive vehicles to reduce fuel consumption without losing power. The project described in this article focuses on the rear differential, because reducing friction here can contribute considerably to efficiency improvement of the whole vehicle. Surfaces, coating and oil viscosity have been investigated and interesting conclusions have been reached. (orig.)

  10. A pilot weight reduction program over one year significantly reduced DNA strand breaks in obese subjects

    Directory of Open Access Journals (Sweden)

    Karl-Heinz Wagner

    2015-05-01

    Conclusion: A sustainable lifestyle change under supervision including physical activity and diet quality over a period of one year was not only responsible to reduce body weight and BMI but also led to significant reduction in all parameters of the comet assay. These results underline the importance of body weight reduction and highlight the positive changes in DNA stability.

  11. Reducing measurement scale mismatch to improve surface energy flux estimation

    Science.gov (United States)

    Iwema, Joost; Rosolem, Rafael; Rahman, Mostaquimur; Blyth, Eleanor; Wagener, Thorsten

    2016-04-01

    Soil moisture importantly controls land surface processes such as energy and water partitioning. A good understanding of these controls is needed especially when recognizing the challenges in providing accurate hyper-resolution hydrometeorological simulations at sub-kilometre scales. Soil moisture controlling factors can, however, differ at distinct scales. In addition, some parameters in land surface models are still often prescribed based on observations obtained at another scale not necessarily employed by such models (e.g., soil properties obtained from lab samples used in regional simulations). To minimize such effects, parameters can be constrained with local data from Eddy-Covariance (EC) towers (i.e., latent and sensible heat fluxes) and Point Scale (PS) soil moisture observations (e.g., TDR). However, measurement scales represented by EC and PS still differ substantially. Here we use the fact that Cosmic-Ray Neutron Sensors (CRNS) estimate soil moisture at horizontal footprint similar to that of EC fluxes to help answer the following question: Does reduced observation scale mismatch yield better soil moisture - surface fluxes representation in land surface models? To answer this question we analysed soil moisture and surface fluxes measurements from twelve COSMOS-Ameriflux sites in the USA characterized by distinct climate, soils and vegetation types. We calibrated model parameters of the Joint UK Land Environment Simulator (JULES) against PS and CRNS soil moisture data, respectively. We analysed the improvement in soil moisture estimation compared to uncalibrated model simulations and then evaluated the degree of improvement in surface fluxes before and after calibration experiments. Preliminary results suggest that a more accurate representation of soil moisture dynamics is achieved when calibrating against observed soil moisture and further improvement obtained with CRNS relative to PS. However, our results also suggest that a more accurate

  12. Reduced content of chloroatranol and atranol in oak moss absolute significantly reduces the elicitation potential of this fragrance material

    DEFF Research Database (Denmark)

    Andersen, Flemming; Andersen, Kirsten H; Bernois, Armand;

    2015-01-01

    BACKGROUND: Oak moss absolute, an extract from the lichen Evernia prunastri, is a valued perfume ingredient but contains extreme allergens. OBJECTIVES: To compare the elicitation properties of two preparations of oak moss absolute: 'classic oak moss', the historically used preparation, and 'new oak...... moss', with reduced contents of the major allergens atranol and chloroatranol. PATIENTS/MATERIALS/METHODS: The two preparations were compared in randomized double-blinded repeated open application tests and serial dilution patch tests in 30 oak moss-sensitive volunteers and 30 non-allergic control...... subjects. RESULTS: In both test models, new oak moss elicited significantly less allergic contact dermatitis in oak moss-sensitive subjects than classic oak moss. The control subjects did not react to either of the preparations. CONCLUSIONS: New oak moss is still a fragrance allergen, but elicits less...

  13. Lactobacillus plantarum TN627 significantly reduces complications of alloxan-induced diabetes in rats.

    Science.gov (United States)

    Bejar, Wacim; Hamden, Khaled; Ben Salah, Riadh; Chouayekh, Hichem

    2013-12-01

    This study aimed to assess the potential of the probiotic strain Lactobacillus plantarum TN627 for preventing alloxan-induced diabetes in rats. The oral administration of this probiotic was noted to significantly improve the immunological parameters, protect the pancreatic tissues, and reduce the pancreatic and plasmatic α-amylase activities and level of plasma glucose in the treated as compared to the control group of rats. Furthermore, this probiotic treatment was observed to markedly reduce pancreatic and plasmatic lipase activities and serum triglyceride and LDL-cholesterol rates and to increase the level of HDL-Cholesterol. It also exerted efficient protective effects on the liver and kidney functions evidenced by significant decreases in serum aspartate transaminase, alanine transaminase, lactate dehydrogenase, and gamma-glutamyl transpeptidase activities, as well as creatinine and urea contents. Taken together, the findings indicate that L. plantarum TN627 exhibits attractive in vivo antidiabetic effects that may be helpful in preventing diabetic complications in adult rats.

  14. Reduced Expression of PTEN Protein and Its Prognostic Significance in the Gastrointestinal Stromal Tumor

    Institute of Scientific and Technical Information of China (English)

    张永红; 于冬冬; 李小兰; 胡俊波; 龚建平

    2010-01-01

    Little is reported about the role of PTEN gene in the progression and prognosis of GISTs.This study examined the clinical implications of the tumor suppressor gene PTEN as a prognostic factor in the GISTs.Immunohistological staining and immunoblotting were employed to examine the PTEN protein expression,and its association with clinical measures.Clinicopathological features were reviewed by a retrospective examination of medical records.Reduced PTEN expression was significantly associated with tumor diamete...

  15. Thrombolysis significantly reduces transient myocardial ischaemia following first acute myocardial infarction

    DEFF Research Database (Denmark)

    Mickley, H; Pless, P; Nielsen, J R

    1992-01-01

    In order to investigate whether thrombolysis affects residual myocardial ischaemia, we prospectively performed a predischarge maximal exercise test and early out-of-hospital ambulatory ST segment monitoring in 123 consecutive men surviving a first acute myocardial infarction (AMI). Seventy...... less than 0.02). Thrombolysis resulted in a non-significant reduction in exercise-induced ST segment depression: prevalence 43% vs 62% in controls. However, during ambulatory monitoring the duration of transient myocardial ischaemia was significantly reduced in thrombolysed patients: 322 min vs 1144...... myocardial ischaemia. This may explain the improvement in myocardial function during physical activities, which was also observed in this study....

  16. Aerodynamic Improvements of an Empty Timber Truck can Have the Potential of Significantly Reducing Fuel Consumption

    Science.gov (United States)

    Andersson, Magnus; Marashi, Seyedeh Sepideh; Karlsson, Matts

    2012-11-01

    In the present study, aerodynamic drag (AD) has been estimated for an empty and a fully loaded conceptual timber truck (TT) using Computational Fluid Dynamics (CFD). The increasing fuel prices have challenged heavy duty vehicle (HDV) manufactures to strive for better fuel economy, by e.g. utilizing drag reducing external devices. Despite this knowledge, the TT fleets seem to be left in the dark. Like HDV aerodynamics, similarities can be observed as a large low pressure wake is formed behind the tractor (unloaded) and downstream of the trailer (full load) thus generating AD. As TTs travel half the time without any cargo, focus on drag reduction is important. The full scaled TTs where simulated using the realizable k-epsilon model with grid adaption techniques for mesh independence. Our results indicate that a loaded TT reduces the AD significantly as both wake size and turbulence kinetic energy are lowered. In contrast to HDV the unloaded TTs have a much larger design space available for possible drag reducing devices, e.g. plastic wrapping and/or flaps. This conceptual CFD study has given an indication of the large AD difference between the unloaded and fully loaded TT, showing the potential for significant AD improvements.

  17. A chimpanzee recognizes synthetic speech with significantly reduced acoustic cues to phonetic content.

    Science.gov (United States)

    Heimbauer, Lisa A; Beran, Michael J; Owren, Michael J

    2011-07-26

    A long-standing debate concerns whether humans are specialized for speech perception, which some researchers argue is demonstrated by the ability to understand synthetic speech with significantly reduced acoustic cues to phonetic content. We tested a chimpanzee (Pan troglodytes) that recognizes 128 spoken words, asking whether she could understand such speech. Three experiments presented 48 individual words, with the animal selecting a corresponding visuographic symbol from among four alternatives. Experiment 1 tested spectrally reduced, noise-vocoded (NV) synthesis, originally developed to simulate input received by human cochlear-implant users. Experiment 2 tested "impossibly unspeechlike" sine-wave (SW) synthesis, which reduces speech to just three moving tones. Although receiving only intermittent and noncontingent reward, the chimpanzee performed well above chance level, including when hearing synthetic versions for the first time. Recognition of SW words was least accurate but improved in experiment 3 when natural words in the same session were rewarded. The chimpanzee was more accurate with NV than SW versions, as were 32 human participants hearing these items. The chimpanzee's ability to spontaneously recognize acoustically reduced synthetic words suggests that experience rather than specialization is critical for speech-perception capabilities that some have suggested are uniquely human. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Reduced content of chloroatranol and atranol in oak moss absolute significantly reduces the elicitation potential of this fragrance material.

    Science.gov (United States)

    Andersen, Flemming; Andersen, Kirsten H; Bernois, Armand; Brault, Christophe; Bruze, Magnus; Eudes, Hervé; Gadras, Catherine; Signoret, Anne-Cécile J; Mose, Kristian F; Müller, Boris P; Toulemonde, Bernard; Andersen, Klaus Ejner

    2015-02-01

    Oak moss absolute, an extract from the lichen Evernia prunastri, is a valued perfume ingredient but contains extreme allergens. To compare the elicitation properties of two preparations of oak moss absolute: 'classic oak moss', the historically used preparation, and 'new oak moss', with reduced contents of the major allergens atranol and chloroatranol. The two preparations were compared in randomized double-blinded repeated open application tests and serial dilution patch tests in 30 oak moss-sensitive volunteers and 30 non-allergic control subjects. In both test models, new oak moss elicited significantly less allergic contact dermatitis in oak moss-sensitive subjects than classic oak moss. The control subjects did not react to either of the preparations. New oak moss is still a fragrance allergen, but elicits less allergic contact dermatitis in previously oak moss-sensitized individuals, suggesting that new oak moss is less allergenic to non-sensitized individuals. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Reduced fouling of ultrafiltration membranes via surface fluorination

    Energy Technology Data Exchange (ETDEWEB)

    Sedath, R.H.; Yates, S.F.; Li, N.N.

    1993-03-01

    Surface fluorination can affect significantly the performance of an ultrafiltration membrane used to concentrate a food-related stream. Membranes fluorinated and tested as flat sheets exhibit higher initial fluxes, and do not foul as rapidly as untreated membranes. This improvement is linked to increased surface hydrophilicity, as shown in decreased contact angle with water. This increased hydrophilicity, in turn, is linked to the addition of fluorine and oxygen to the surface. The pilot plant study did-not show the difference in membrane flux and fouling observed in the flat sheet study. Instead, fluorinated and unfluorinated modules behaved similarly. Fouling by potato waste feed was severe and resulted in formation of an extensive gel layer within the module on the membrane surface. XPS, SEM and FTIR indicate that buildup of organic material occurred on both fluorinated and unfluorinated membranes, but SEM indicates that a fibrous mat of material was observed only on the nonfluorinated membrane. We conclude that in the pilot study, membrane fouling and gel formation were so extensive that the surface interaction effect was overwhelmed.

  20. Towards Reducing the Data Exfiltration Surface for the Insider Threat

    Energy Technology Data Exchange (ETDEWEB)

    Schlicher, Bob G [ORNL; MacIntyre, Lawrence Paul [ORNL; Abercrombie, Robert K [ORNL

    2016-01-01

    Unauthorized data exfiltrations from both insiders and outsiders are costly and damaging. Network communication resources can be used for transporting data illicitly out of the enterprise or cloud. Combined with built-in malware copying utilities, we define this as comprising the Data Exfiltration Surface (DXS). For securing valuable data, it is desirable to reduce the DXS and maintain controls on the egress points. Our approach is to host the data in a protected enclave that includes novel software Data Diode (SDD) installed on a secured, border gateway. The SDD allows copying data into the enclave systems but denies data from being copied out. Simultaneously, it permits remote access with remote desktop and console applications. Our tests demonstrate that we are able to effectively reduce the DXS and we are able to protect data from being exfiltrated through the use of the SDD.

  1. Aluminum sulfate significantly reduces the skin test response to common allergens in sensitized patients

    Directory of Open Access Journals (Sweden)

    Grier Thomas J

    2006-02-01

    Full Text Available Abstract Background Avoidance of allergens is still recommended as the first and best way to prevent allergic illnesses and their comorbid diseases. Despite a variety of attempts there has been very limited success in the area of environmental control of allergic disease. Our objective was to identify a non-invasive, non-pharmacological method to reduce indoor allergen loads in atopic persons' homes and public environments. We employed a novel in vivo approach to examine the possibility of using aluminum sulfate to control environmental allergens. Methods Fifty skin test reactive patients were simultaneously skin tested with conventional test materials and the actions of the protein/glycoprotein modifier, aluminum sulfate. Common allergens, dog, cat, dust mite, Alternaria, and cockroach were used in the study. Results Skin test reactivity was significantly reduced by the modifier aluminum sulfate. Our studies demonstrate that the effects of histamine were not affected by the presence of aluminum sulfate. In fact, skin test reactivity was reduced independent of whether aluminum sulfate was present in the allergen test material or removed prior to testing, indicating that the allergens had in some way been inactivated. Conclusion Aluminum sulfate was found to reduce the in vivo allergic reaction cascade induced by skin testing with common allergens. The exact mechanism is not clear but appears to involve the alteration of IgE-binding epitopes on the allergen. Our results indicate that it may be possible to diminish the allergenicity of an environment by application of the active agent aluminum sulfate, thus producing environmental control without complete removal of the allergen.

  2. Significantly enhanced lung metastasis and reduced organ NK cell functions in diet-induced obese rats.

    Science.gov (United States)

    Spielmann, J; Hanke, J; Knauf, D; Ben-Eliyahu, S; Jacobs, R; Stangl, G I; Bähr, I; Kielstein, H

    2017-01-01

    Obesity was identified as a major risk factor for malignant diseases, but underlying mechanisms remain unclear. Natural killer (NK) cells, a pivotal aspect of innate immunity, are capable of identifying and killing virally infected and tumor cells. Previous studies have shown altered NK cell functions in obesity, and the current study aimed to investigate the relationship between altered NK cell functions and increased cancer risk in obesity. To induce obesity male F344-rats received a high-fat diet (34% fat) or a control diet (4% fat). Thereafter, syngeneic mammary adenocarcinoma cells (MADB106) or a vehicle were intravenously (i.v.) injected. 15 min after injection, half of each group of rats were killed, lungs removed and immunohistochemically stained. Numbers of NK cells, MADB106 cells and NK cell-tumor cell interactions were quantified. Twenty-one days after tumor-cell injection the other half group of rats was killed and lung metastases were counted and relative mRNA concentrations of different NK cell receptors were determined. After short-term MADB106-challenge, DIO fed animals showed significantly decreased NK cell numbers in the blood and NK cell-tumor cell interactions in the lung as compared to their control littermates. Twenty-one days after MADB106 injection, the lungs of the DIO fed rats showed significantly more lung metastases compared to control animals, accompanied by reduced relative mRNA concentrations of the activating NK cell receptor NKG2D. We conclude that induction of obesity in F344-rats leads to reduced lung NK cell function against tumor cells and results in significantly enhanced lung metastasis as compared to lean animals. It can be hypothesized that obesity-induced altered NK cell functions play an important role in cancer growth and metastasis.

  3. Use of preoperative gabapentin significantly reduces postoperative opioid consumption: a meta-analysis

    Science.gov (United States)

    Arumugam, Sudha; Lau, Christine SM; Chamberlain, Ronald S

    2016-01-01

    Objectives Effective postoperative pain management is crucial in the care of surgical patients. Opioids, which are commonly used in managing postoperative pain, have a potential for tolerance and addiction, along with sedating side effects. Gabapentin’s use as a multimodal analgesic regimen to treat neuropathic pain has been documented as having favorable side effects. This meta-analysis examined the use of preoperative gabapentin and its impact on postoperative opioid consumption. Materials and methods A comprehensive literature search was conducted to identify randomized control trials that evaluated preoperative gabapentin on postoperative opioid consumption. The outcomes of interest were cumulative opioid consumption following the surgery and the incidence of vomiting, somnolence, and nausea. Results A total of 1,793 patients involved in 17 randomized control trials formed the final analysis for this study. Postoperative opioid consumption was reduced when using gabapentin within the initial 24 hours following surgery (standard mean difference −1.35, 95% confidence interval [CI]: −1.96 to −0.73; Pfentanyl, and tramadol consumption (P<0.05). While a significant increase in postoperative somnolence incidence was observed (relative risk 1.30, 95% CI: 1.10–1.54, P<0.05), there were no significant effects on postoperative vomiting and nausea. Conclusion The administration of preoperative gabapentin reduced the consumption of opioids during the initial 24 hours following surgery. The reduction in postoperative opioids with preoperative gabapentin increased postoperative somnolence, but no significant differences were observed in nausea and vomiting incidences. The results from this study demonstrate that gabapentin is more beneficial in mastectomy and spinal, abdominal, and thyroid surgeries. Gabapentin is an effective analgesic adjunct, and clinicians should consider its use in multimodal treatment plans among patients undergoing elective surgery. PMID

  4. Improved chemical and electrochemical stability of perovskite oxides with less reducible cations at the surface

    Science.gov (United States)

    Tsvetkov, Nikolai; Lu, Qiyang; Sun, Lixin; Crumlin, Ethan J.; Yildiz, Bilge

    2016-09-01

    Segregation and phase separation of aliovalent dopants on perovskite oxide (ABO3) surfaces are detrimental to the performance of energy conversion systems such as solid oxide fuel/electrolysis cells and catalysts for thermochemical H2O and CO2 splitting. One key reason behind the instability of perovskite oxide surfaces is the electrostatic attraction of the negatively charged A-site dopants (for example, ) by the positively charged oxygen vacancies () enriched at the surface. Here we show that reducing the surface concentration improves the oxygen surface exchange kinetics and stability significantly, albeit contrary to the well-established understanding that surface oxygen vacancies facilitate reactions with O2 molecules. We take La0.8Sr0.2CoO3 (LSC) as a model perovskite oxide, and modify its surface with additive cations that are more and less reducible than Co on the B-site of LSC. By using ambient-pressure X-ray absorption and photoelectron spectroscopy, we proved that the dominant role of the less reducible cations is to suppress the enrichment and phase separation of Sr while reducing the concentration of and making the LSC more oxidized at its surface. Consequently, we found that these less reducible cations significantly improve stability, with up to 30 times faster oxygen exchange kinetics after 54 h in air at 530 °C achieved by Hf addition onto LSC. Finally, the results revealed a `volcano' relation between the oxygen exchange kinetics and the oxygen vacancy formation enthalpy of the binary oxides of the additive cations. This volcano relation highlights the existence of an optimum surface oxygen vacancy concentration that balances the gain in oxygen exchange kinetics and the chemical stability loss.

  5. Long-term stable polymer solar cells with significantly reduced burn-in loss.

    Science.gov (United States)

    Kong, Jaemin; Song, Suhee; Yoo, Minji; Lee, Ga Young; Kwon, Obum; Park, Jin Kuen; Back, Hyungcheol; Kim, Geunjin; Lee, Seoung Ho; Suh, Hongsuk; Lee, Kwanghee

    2014-12-08

    The inferior long-term stability of polymer-based solar cells needs to be overcome for their commercialization to be viable. In particular, an abrupt decrease in performance during initial device operation, the so-called 'burn-in' loss, has been a major contributor to the short lifetime of polymer solar cells, fundamentally impeding polymer-based photovoltaic technology. In this study, we demonstrate polymer solar cells with significantly improved lifetime, in which an initial burn-in loss is substantially reduced. By isolating trap-embedded components from pristine photoactive polymers based on the unimodality of molecular weight distributions, we are able to selectively extract a trap-free, high-molecular-weight component. The resulting polymer component exhibits enhanced power conversion efficiency and long-term stability without abrupt initial burn-in degradation. Our discovery suggests a promising possibility for commercial viability of polymer-based photovoltaics towards real solar cell applications.

  6. Nano-CL-20/HMX Cocrystal Explosive for Significantly Reduced Mechanical Sensitivity

    Directory of Open Access Journals (Sweden)

    Chongwei An

    2017-01-01

    Full Text Available Spray drying method was used to prepare cocrystals of hexanitrohexaazaisowurtzitane (CL-20 and cyclotetramethylene tetranitramine (HMX. Raw materials and cocrystals were characterized using scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, Raman spectroscopy, and Fourier transform infrared spectroscopy. Impact and friction sensitivity of cocrystals were tested and analyzed. Results show that, after preparation by spray drying method, microparticles were spherical in shape and 0.5–5 µm in size. Particles formed aggregates of numerous tiny plate-like cocrystals, whereas CL-20/HMX cocrystals had thicknesses of below 100 nm. Cocrystals were formed by C–H⋯O bonding between –NO2 (CL-20 and –CH2– (HMX. Nanococrystal explosives exhibited drop height of 47.3 cm, and friction demonstrated explosion probability of 64%. Compared with raw HMX, cocrystals displayed significantly reduced mechanical sensitivity.

  7. Density functional theory study of water adsorption at reduced and stoichiometric ceria (111) surfaces.

    Science.gov (United States)

    Kumar, Santosh; Schelling, Patrick K

    2006-11-28

    We study the structure and energetics of water molecules adsorbed at ceria (111) surfaces for 0.5 and 1.0 ML coverages using density functional theory. The results of this study provide a theoretical framework for interpreting recent experimental results on the redox properties of water at ceria (111) surfaces. In particular, we have computed the structure and energetics of various absorption geometries at the stoichiometric ceria (111) surface. We find that single hydrogen bonds between the water and the oxide surface are favored in all cases. At stoichiometric surfaces, the water adsorption energy depends rather weakly on coverage. We predict that the observed coverage dependence of the water adsorption energy at stoichiometric surfaces is likely the result of dipole-dipole interactions between adsorbed water molecules. When oxygen vacancies are introduced in various surface layers, water molecules are attracted more strongly to the surface. We find that it is very slightly energetically favorable for adsorbed water to oxidized the reduced (111) surface with the evolution of H(2). In the event that water does not oxidize the surface, we predict that the effective attractive water-vacancy interaction will result in a significant enhancement of the vacancy concentration at the surface in agreement with experimental observations. Finally, we present our results in the context of recent experimental and theoretical studies of vacancy clustering at the (111) ceria surface.

  8. Cleanroom Maintenance Significantly Reduces Abundance but Not Diversity of Indoor Microbiomes

    Science.gov (United States)

    Mahnert, Alexander; Vaishampayan, Parag; Probst, Alexander J.; Auerbach, Anna; Moissl-Eichinger, Christine; Venkateswaran, Kasthuri; Berg, Gabriele

    2015-01-01

    Cleanrooms have been considered microbially-reduced environments and are used to protect human health and industrial product assembly. However, recent analyses have deciphered a rather broad diversity of microbes in cleanrooms, whose origin as well as physiological status has not been fully understood. Here, we examined the input of intact microbial cells from a surrounding built environment into a spacecraft assembly cleanroom by applying a molecular viability assay based on propidium monoazide (PMA). The controlled cleanroom (CCR) was characterized by ~6.2*103 16S rRNA gene copies of intact bacterial cells per m2 floor surface, which only represented 1% of the total community that could be captured via molecular assays without viability marker. This was in contrast to the uncontrolled adjoining facility (UAF) that had 12 times more living bacteria. Regarding diversity measures retrieved from 16S rRNA Illumina-tag analyzes, we observed, however, only a minor drop in the cleanroom facility allowing the conclusion that the number but not the diversity of microbes is strongly affected by cleaning procedures. Network analyses allowed tracking a substantial input of living microbes to the cleanroom and a potential enrichment of survival specialists like bacterial spore formers and archaeal halophiles and mesophiles. Moreover, the cleanroom harbored a unique community including 11 exclusive genera, e.g., Haloferax and Sporosarcina, which are herein suggested as indicators of cleanroom environments. In sum, our findings provide evidence that archaea are alive in cleanrooms and that cleaning efforts and cleanroom maintenance substantially decrease the number but not the diversity of indoor microbiomes. PMID:26273838

  9. Cleanroom Maintenance Significantly Reduces Abundance but Not Diversity of Indoor Microbiomes.

    Science.gov (United States)

    Mahnert, Alexander; Vaishampayan, Parag; Probst, Alexander J; Auerbach, Anna; Moissl-Eichinger, Christine; Venkateswaran, Kasthuri; Berg, Gabriele

    2015-01-01

    Cleanrooms have been considered microbially-reduced environments and are used to protect human health and industrial product assembly. However, recent analyses have deciphered a rather broad diversity of microbes in cleanrooms, whose origin as well as physiological status has not been fully understood. Here, we examined the input of intact microbial cells from a surrounding built environment into a spacecraft assembly cleanroom by applying a molecular viability assay based on propidium monoazide (PMA). The controlled cleanroom (CCR) was characterized by ~6.2*103 16S rRNA gene copies of intact bacterial cells per m2 floor surface, which only represented 1% of the total community that could be captured via molecular assays without viability marker. This was in contrast to the uncontrolled adjoining facility (UAF) that had 12 times more living bacteria. Regarding diversity measures retrieved from 16S rRNA Illumina-tag analyzes, we observed, however, only a minor drop in the cleanroom facility allowing the conclusion that the number but not the diversity of microbes is strongly affected by cleaning procedures. Network analyses allowed tracking a substantial input of living microbes to the cleanroom and a potential enrichment of survival specialists like bacterial spore formers and archaeal halophiles and mesophiles. Moreover, the cleanroom harbored a unique community including 11 exclusive genera, e.g., Haloferax and Sporosarcina, which are herein suggested as indicators of cleanroom environments. In sum, our findings provide evidence that archaea are alive in cleanrooms and that cleaning efforts and cleanroom maintenance substantially decrease the number but not the diversity of indoor microbiomes.

  10. Cleanroom Maintenance Significantly Reduces Abundance but Not Diversity of Indoor Microbiomes.

    Directory of Open Access Journals (Sweden)

    Alexander Mahnert

    Full Text Available Cleanrooms have been considered microbially-reduced environments and are used to protect human health and industrial product assembly. However, recent analyses have deciphered a rather broad diversity of microbes in cleanrooms, whose origin as well as physiological status has not been fully understood. Here, we examined the input of intact microbial cells from a surrounding built environment into a spacecraft assembly cleanroom by applying a molecular viability assay based on propidium monoazide (PMA. The controlled cleanroom (CCR was characterized by ~6.2*103 16S rRNA gene copies of intact bacterial cells per m2 floor surface, which only represented 1% of the total community that could be captured via molecular assays without viability marker. This was in contrast to the uncontrolled adjoining facility (UAF that had 12 times more living bacteria. Regarding diversity measures retrieved from 16S rRNA Illumina-tag analyzes, we observed, however, only a minor drop in the cleanroom facility allowing the conclusion that the number but not the diversity of microbes is strongly affected by cleaning procedures. Network analyses allowed tracking a substantial input of living microbes to the cleanroom and a potential enrichment of survival specialists like bacterial spore formers and archaeal halophiles and mesophiles. Moreover, the cleanroom harbored a unique community including 11 exclusive genera, e.g., Haloferax and Sporosarcina, which are herein suggested as indicators of cleanroom environments. In sum, our findings provide evidence that archaea are alive in cleanrooms and that cleaning efforts and cleanroom maintenance substantially decrease the number but not the diversity of indoor microbiomes.

  11. Pharmacological kynurenine 3-monooxygenase enzyme inhibition significantly reduces neuropathic pain in a rat model.

    Science.gov (United States)

    Rojewska, Ewelina; Piotrowska, Anna; Makuch, Wioletta; Przewlocka, Barbara; Mika, Joanna

    2016-03-01

    Recent studies have highlighted the involvement of the kynurenine pathway in the pathology of neurodegenerative diseases, but the role of this system in neuropathic pain requires further extensive research. Therefore, the aim of our study was to examine the role of kynurenine 3-monooxygenase (Kmo), an enzyme that is important in this pathway, in a rat model of neuropathy after chronic constriction injury (CCI) to the sciatic nerve. For the first time, we demonstrated that the injury-induced increase in the Kmo mRNA levels in the spinal cord and the dorsal root ganglia (DRG) was reduced by chronic administration of the microglial inhibitor minocycline and that this effect paralleled a decrease in the intensity of neuropathy. Further, minocycline administration alleviated the lipopolysaccharide (LPS)-induced upregulation of Kmo mRNA expression in microglial cell cultures. Moreover, we demonstrated that not only indirect inhibition of Kmo using minocycline but also direct inhibition using Kmo inhibitors (Ro61-6048 and JM6) decreased neuropathic pain intensity on the third and the seventh days after CCI. Chronic Ro61-6048 administration diminished the protein levels of IBA-1, IL-6, IL-1beta and NOS2 in the spinal cord and/or the DRG. Both Kmo inhibitors potentiated the analgesic properties of morphine. In summary, our data suggest that in neuropathic pain model, inhibiting Kmo function significantly reduces pain symptoms and enhances the effectiveness of morphine. The results of our studies show that the kynurenine pathway is an important mediator of neuropathic pain pathology and indicate that Kmo represents a novel pharmacological target for the treatment of neuropathy.

  12. On the Use of Surface Porosity to Reduce Unsteady Lift

    Science.gov (United States)

    Tinetti, Ana F.; Kelly, Jeffrey J.; Bauer, Steven X. S.; Thomas, Russell H.

    2001-01-01

    An innovative application of existing technology is proposed for attenuating the effects of transient phenomena, such as rotor-stator and rotor-strut interactions, linked to noise and fatigue failure in turbomachinery environments. A computational study was designed to assess the potential of passive porosity technology as a mechanism for alleviating interaction effects by reducing the unsteady lift developed on a stator airfoil subject to wake impingement. The study involved a typical high bypass fan Stator airfoil (solid baseline and several porous configurations), immersed in a free field and exposed to the effects of a transversely moving wake. It was found that, for the airfoil under consideration, the magnitude of the unsteady lift could be reduced more than 18% without incurring significant performance losses.

  13. Observing seasonal variations of sea surface wind speed and significant wave height using TOPEX altimetry

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    One year of ocean topography experiment (TOPEX) altimeter data are used to study the seasonal variations of global sea surface wind speed and significant wave height. The major wind and wave zones of the world oceans are precisely identified, their seasonal variability and characteristics are quantitatively analyzed, and the diversity of global wind speed seasonality and the variability of significant wave height in response to sea surface wind speed are also revealed.

  14. Significantly reduced hypoxemic events in morbidly obese patients undergoing gastrointestinal endoscopy: Predictors and practice effect

    Directory of Open Access Journals (Sweden)

    Basavana Gouda Goudra

    2014-01-01

    Full Text Available Background: Providing anesthesia for gastrointestinal (GI endoscopy procedures in morbidly obese patients is a challenge for a variety of reasons. The negative impact of obesity on the respiratory system combined with a need to share the upper airway and necessity to preserve the spontaneous ventilation, together add to difficulties. Materials and Methods: This retrospective cohort study included patients with a body mass index (BMI >40 kg/m 2 that underwent out-patient GI endoscopy between September 2010 and February 2011. Patient data was analyzed for procedure, airway management technique as well as hypoxemic and cardiovascular events. Results: A total of 119 patients met the inclusion criteria. Our innovative airway management technique resulted in a lower rate of intraoperative hypoxemic events compared with any published data available. Frequency of desaturation episodes showed statistically significant relation to previous history of obstructive sleep apnea (OSA. These desaturation episodes were found to be statistically independent of increasing BMI of patients. Conclusion: Pre-operative history of OSA irrespective of associated BMI values can be potentially used as a predictor of intra-procedural desaturation. With suitable modification of anesthesia technique, it is possible to reduce the incidence of adverse respiratory events in morbidly obese patients undergoing GI endoscopy procedures, thereby avoiding the need for endotracheal intubation.

  15. Significantly reduced hypoxemic events in morbidly obese patients undergoing gastrointestinal endoscopy: Predictors and practice effect.

    Science.gov (United States)

    Goudra, Basavana Gouda; Singh, Preet Mohinder; Penugonda, Lakshmi C; Speck, Rebecca M; Sinha, Ashish C

    2014-01-01

    Providing anesthesia for gastrointestinal (GI) endoscopy procedures in morbidly obese patients is a challenge for a variety of reasons. The negative impact of obesity on the respiratory system combined with a need to share the upper airway and necessity to preserve the spontaneous ventilation, together add to difficulties. This retrospective cohort study included patients with a body mass index (BMI) >40 kg/m(2) that underwent out-patient GI endoscopy between September 2010 and February 2011. Patient data was analyzed for procedure, airway management technique as well as hypoxemic and cardiovascular events. A total of 119 patients met the inclusion criteria. Our innovative airway management technique resulted in a lower rate of intraoperative hypoxemic events compared with any published data available. Frequency of desaturation episodes showed statistically significant relation to previous history of obstructive sleep apnea (OSA). These desaturation episodes were found to be statistically independent of increasing BMI of patients. Pre-operative history of OSA irrespective of associated BMI values can be potentially used as a predictor of intra-procedural desaturation. With suitable modification of anesthesia technique, it is possible to reduce the incidence of adverse respiratory events in morbidly obese patients undergoing GI endoscopy procedures, thereby avoiding the need for endotracheal intubation.

  16. Significance of nano- and microtopography for cell-surface interactions in orthopaedic implants.

    Science.gov (United States)

    Jäger, M; Zilkens, C; Zanger, K; Krauspe, R

    2007-01-01

    Cell-surface interactions play a crucial role for biomaterial application in orthopaedics. It is evident that not only the chemical composition of solid substances influence cellular adherence, migration, proliferation and differentiation but also the surface topography of a biomaterial. The progressive application of nanostructured surfaces in medicine has gained increasing interest to improve the cytocompatibility and osteointegration of orthopaedic implants. Therefore, the understanding of cell-surface interactions is of major interest for these substances. In this review, we elucidate the principle mechanisms of nano- and microscale cell-surface interactions in vitro for different cell types onto typical orthopaedic biomaterials such as titanium (Ti), cobalt-chrome-molybdenum (CoCrMo) alloys, stainless steel (SS), as well as synthetic polymers (UHMWPE, XLPE, PEEK, PLLA). In addition, effects of nano- and microscaled particles and their significance in orthopaedics were reviewed. The significance for the cytocompatibility of nanobiomaterials is discussed critically.

  17. Largely Reduced Grid Densities in a Vibrational Self-Consistent Field Treatment Do Not Significantly Impact the ResultingWavenumbers

    Directory of Open Access Journals (Sweden)

    Oliver M. D. Lutz

    2014-12-01

    Full Text Available Especially for larger molecules relevant to life sciences, vibrational self-consistent field (VSCF calculations can become unmanageably demanding even when only first and second order potential coupling terms are considered. This paper investigates to what extent the grid density of the VSCF’s underlying potential energy surface can be reduced without sacrificing accuracy of the resulting wavenumbers. Including single-mode and pair contributions, a reduction to eight points per mode did not introduce a significant deviation but improved the computational efficiency by a factor of four. A mean unsigned deviation of 1.3% from the experiment could be maintained for the fifteen molecules under investigation and the approach was found to be applicable to rigid, semi-rigid and soft vibrational problems likewise. Deprotonated phosphoserine, stabilized by two intramolecular hydrogen bonds, was investigated as an exemplary application.

  18. Using a respiratory navigator significantly reduces variability when quantifying left ventricular torsion with cardiovascular magnetic resonance.

    Science.gov (United States)

    Hamlet, Sean M; Haggerty, Christopher M; Suever, Jonathan D; Wehner, Gregory J; Andres, Kristin N; Powell, David K; Charnigo, Richard J; Fornwalt, Brandon K

    2017-03-01

    respiratory variability from consecutive breath-holds translated to a variability in torsion of 0.24 ± 0.10°/cm, which was significantly higher than the variability from navigator-gated scans (0.18 ± 0.06°/cm, p = 0.02). By using a respiratory navigator with DENSE, theoretical sample sizes were reduced from 66 to 16 and 26 to 15 as calculated from the two experiments. A substantial portion (22-57%) of the inter-test variability of LV torsion can be reduced by using a respiratory navigator to ensure a consistent breath-hold position between image acquisitions.

  19. Weight Loss Through Lifestyle Modification Significantly Reduces Features of Nonalcoholic Steatohepatitis.

    Science.gov (United States)

    Vilar-Gomez, Eduardo; Martinez-Perez, Yadina; Calzadilla-Bertot, Luis; Torres-Gonzalez, Ana; Gra-Oramas, Bienvenido; Gonzalez-Fabian, Licet; Friedman, Scott L; Diago, Moises; Romero-Gomez, Manuel

    2015-08-01

    It is not clear how weight loss affects histologic features of liver in patients with nonalcoholic steatohepatitis (NASH). We examined the association between the magnitude of weight loss through lifestyle modifications and changes in histologic features of NASH. We conducted a prospective study of 293 patients with histologically proven NASH who were encouraged to adopt recommended lifestyle changes to reduce their weight over 52 weeks, from June 2009 through May 2013, at a tertiary medical center in Havana, Cuba. Liver biopsies were collected when the study began and at week 52 of the diet and were analyzed histologically. Paired liver biopsies were available from 261 patients. Among 293 patients who underwent lifestyle changes for 52 weeks, 72 (25%) achieved resolution of steatohepatitis, 138 (47%) had reductions in nonalcoholic fatty liver disease activity score (NAS), and 56 (19%) had regression of fibrosis. At week fifty-two, 88 subjects (30%) had lost ≥5% of their weight. Degree of weight loss was independently associated with improvements in all NASH-related histologic parameters (odds ratios = 1.1-2.0; P fasting glucose >5.5 mmol/L, and many ballooned cells, NAS scores decreased significantly with weight reductions ≥10%. A greater extent of weight loss, induced by lifestyle changes, is associated with the level of improvement in histologic features of NASH. The highest rates of NAS reduction, NASH resolution, and fibrosis regression occurred in patients with weight losses ≥10%. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.

  20. Soil nitrate reducing processes – drivers, mechanisms for spatial variation, and significance for nitrous oxide production

    Science.gov (United States)

    Giles, Madeline; Morley, Nicholas; Baggs, Elizabeth M.; Daniell, Tim J.

    2012-01-01

    The microbial processes of denitrification and dissimilatory nitrate reduction to ammonium (DNRA) are two important nitrate reducing mechanisms in soil, which are responsible for the loss of nitrate (NO3−) and production of the potent greenhouse gas, nitrous oxide (N2O). A number of factors are known to control these processes, including O2 concentrations and moisture content, N, C, pH, and the size and community structure of nitrate reducing organisms responsible for the processes. There is an increasing understanding associated with many of these controls on flux through the nitrogen cycle in soil systems. However, there remains uncertainty about how the nitrate reducing communities are linked to environmental variables and the flux of products from these processes. The high spatial variability of environmental controls and microbial communities across small sub centimeter areas of soil may prove to be critical in determining why an understanding of the links between biotic and abiotic controls has proved elusive. This spatial effect is often overlooked as a driver of nitrate reducing processes. An increased knowledge of the effects of spatial heterogeneity in soil on nitrate reduction processes will be fundamental in understanding the drivers, location, and potential for N2O production from soils. PMID:23264770

  1. Mindfulness significantly reduces self-reported levels of anxiety and depression

    DEFF Research Database (Denmark)

    Würtzen, Hanne; Dalton, Susanne Oksbjerg; Elsass, Peter

    2013-01-01

    INTRODUCTION: As the incidence of and survival from breast cancer continue to raise, interventions to reduce anxiety and depression before, during and after treatment are needed. Previous studies have reported positive effects of a structured 8-week group mindfulness-based stress reduction program...

  2. Soil nitrate reducing processes – drivers, mechanisms for spatial variation and significance for nitrous oxide production

    Directory of Open Access Journals (Sweden)

    Madeline Eleanore Giles

    2012-12-01

    Full Text Available The microbial processes of denitrification and dissimilatory nitrate reduction to ammonium (DNRA are two important nitrate reducing mechanisms in soil, which are responsible for the loss of nitrate (NO3-¬ and production of the potent greenhouse gas, nitrous oxide (N2O. A number of factors are known to control these processes, including O2 concentrations and moisture content, N, C, pH and the size and community structure of nitrate reducing organisms responsible for the processes. There is an increasing understanding associated with many of these controls on flux through the nitrogen cycle in soil systems. However, there remains uncertainty about how the nitrate reducing communities are linked to environmental variables and the flux of products from these processes. The high spatial variability of environmental controls and microbial communities across small sub cm areas of soil may prove to be critical in determining why an understanding of the links between biotic and abiotic controls has proved elusive. This spatial effect is often overlooked as a driver of nitrate reducing processes. An increased knowledge of the effects of spatial heterogeneity in soil on nitrate reduction processes will be fundamental in understanding the drivers, location and potential for N2O production from soils.

  3. Defibrillator charging before rhythm analysis significantly reduces hands-off time during resuscitation

    DEFF Research Database (Denmark)

    Hansen, L. K.; Folkestad, L.; Brabrand, M.

    2013-01-01

    BACKGROUND: Our objective was to reduce hands-off time during cardiopulmonary resuscitation as increased hands-off time leads to higher mortality. METHODS: The European Resuscitation Council (ERC) 2005 and ERC 2010 guidelines were compared with an alternative sequence (ALT). Pulseless ventricular...

  4. MULTIPLE IMAGING TECHNIQUES DEMONSTRATE THE MANIPULATION OF SURFACES TO REDUCE BACTERIAL CONTAMINATION

    Science.gov (United States)

    Surface imaging techniques were combined to determine appropriate manipulation of technologically important surfaces for commercial applications. Stainless steel surfaces were engineered to reduce bacterial contamination, biofilm formation, and corrosion during product processing...

  5. Reducing dysfunctional beliefs about sleep does not significantly improve insomnia in cognitive behavioral therapy.

    Science.gov (United States)

    Okajima, Isa; Nakajima, Shun; Ochi, Moeko; Inoue, Yuichi

    2014-01-01

    The present study examined to examine whether improvement of insomnia is mediated by a reduction in sleep-related dysfunctional beliefs through cognitive behavioral therapy for insomnia. In total, 64 patients with chronic insomnia received cognitive behavioral therapy for insomnia consisting of 6 biweekly individual treatment sessions of 50 minutes in length. Participants were asked to complete the Athens Insomnia Scale and the Dysfunctional Beliefs and Attitudes about Sleep scale both at the baseline and at the end of treatment. The results showed that although cognitive behavioral therapy for insomnia greatly reduced individuals' scores on both scales, the decrease in dysfunctional beliefs and attitudes about sleep with treatment did not seem to mediate improvement in insomnia. The findings suggest that sleep-related dysfunctional beliefs endorsed by patients with chronic insomnia may be attenuated by cognitive behavioral therapy for insomnia, but changes in such beliefs are not likely to play a crucial role in reducing the severity of insomnia.

  6. Synergy in Sulfur Cycle: The Biogeochemical Significance of Sulfate Reducing Bacteria in Syntrophic Associations

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.

    . In the gutless marine oligochaete Olavius algarvensis, endosymbiotic sulfate-reducing bacteria produce sulphide that can serve as an energy source for sulphide-oxidizing symbionts of the host. Apparently these symbionts do not compete for resources but rather... to tame and harness their potential better- from the coastal realms where they compete successfully with aerobes 33 in the biodegradative processes to the dark abysses of deep ocean beds where they biogeochemically control the rich mineral resources...

  7. Modeling of Reduced Effective Secondary Electron Emission Yield from a Velvet Surface

    CERN Document Server

    Swanson, Charles

    2016-01-01

    Complex structures on a material surface can significantly reduce total secondary electron emission from that surface. A velvet is a surface that consists of an array of vertically standing whiskers. The reduction occurs due to the capture of low-energy, true secondary electrons emitted at the bottom of the structure and on the sides of the velvet whiskers. We performed numerical simulations and developed an approximate analytical model that calculates the net secondary electron emission yield from a velvet surface as a function of the velvet whisker length and packing density, and the angle of incidence of primary electrons. The values of optimal velvet whisker packing density that maximally suppresses secondary electron emission yield are determined as a function of velvet aspect ratio and electron angle of incidence.

  8. The significance of multiple scattering in bubble measurements near the sea surface

    DEFF Research Database (Denmark)

    Jensen, Leif Bjørnø; Bjørnø, Irina K.

    1996-01-01

    The acoustic interactions between gas bubbles in bubble plumes formed near the sea surface may significantly change the propagation and attenuation conditions for acoustical signals in the sea. The scattering properties of the bubble plumes have been studied extensively since Foldy's formulation...

  9. Impact of a Reducing Agent on the Dynamic Surface Properties of Lysozyme Solutions.

    Science.gov (United States)

    Tihonov, Michael M; Kim, Viktoria V; Noskov, Boris A

    2016-05-01

    Disulfide bond shuffling in the presence of the reducing agents dithiothreitol (DTT) or β-mercaptoethanol (BME) strongly affects the surface properties of lysozyme solutions. The addition of 0.32 mM DTT substantially alters the kinetic dependencies of the dynamic surface elasticity and surface tension relative to those of pure protein solutions. The significant increase in the dynamic surface elasticity likely relates to the cross-linking between lysozyme molecules and the formation of a dense layer of protein globules stabilized by intermolecular disulfide bonds at the liquid/gas interface. This effect differs from the previously described influence of chaotropic denaturants, such as guanidine hydrochloride (GuHCl) and urea, on the surface properties of lysozyme solutions. If both chaotropic and reducing agents are added to protein solutions simultaneously, their effects become superimposed. In the case of mixed lysozyme/GuHCl/DTT solutions, the dynamic surface elasticity near equilibrium decreases as the GuHCl concentration increases because of the gradual loosening of the cross-linked layer of protein globules but remains much higher than that of lysozyme/GuHCl solutions.

  10. The Evolution of Polymer Composition during PHA Accumulation: The Significance of Reducing Equivalents

    Directory of Open Access Journals (Sweden)

    Liliana Montano-Herrera

    2017-03-01

    Full Text Available This paper presents a systematic investigation into monomer development during mixed culture Polyhydroxyalkanoates (PHA accumulation involving concurrent active biomass growth and polymer storage. A series of mixed culture PHA accumulation experiments, using several different substrate-feeding strategies, was carried out. The feedstock comprised volatile fatty acids, which were applied as single carbon sources, as mixtures, or in series, using a fed-batch feed-on-demand controlled bioprocess. A dynamic trend in active biomass growth as well as polymer composition was observed. The observations were consistent over replicate accumulations. Metabolic flux analysis (MFA was used to investigate metabolic activity through time. It was concluded that carbon flux, and consequently copolymer composition, could be linked with how reducing equivalents are generated.

  11. Combining contact tracing with targeted indoor residual spraying significantly reduces dengue transmission

    Science.gov (United States)

    Vazquez-Prokopec, Gonzalo M.; Montgomery, Brian L.; Horne, Peter; Clennon, Julie A.; Ritchie, Scott A.

    2017-01-01

    The widespread transmission of dengue viruses (DENV), coupled with the alarming increase of birth defects and neurological disorders associated with Zika virus, has put the world in dire need of more efficacious tools for Aedes aegypti–borne disease mitigation. We quantitatively investigated the epidemiological value of location-based contact tracing (identifying potential out-of-home exposure locations by phone interviews) to infer transmission foci where high-quality insecticide applications can be targeted. Space-time statistical modeling of data from a large epidemic affecting Cairns, Australia, in 2008–2009 revealed a complex pattern of transmission driven primarily by human mobility (Cairns accounted for ~60% of virus transmission to and from residents of satellite towns, and 57% of all potential exposure locations were nonresidential). Targeted indoor residual spraying with insecticides in potential exposure locations reduced the probability of future DENV transmission by 86 to 96%, compared to unsprayed premises. Our findings provide strong evidence for the effectiveness of combining contact tracing with residual spraying within a developed urban center, and should be directly applicable to areas with similar characteristics (for example, southern USA, Europe, or Caribbean countries) that need to control localized Aedes-borne virus transmission or to protect pregnant women’s homes in areas with active Zika transmission. Future theoretical and empirical research should focus on evaluation of the applicability and scalability of this approach to endemic areas with variable population size and force of DENV infection. PMID:28232955

  12. Meteorites at Meridiani Planum provide evidence for significant amounts of surface and near-surface water on early Mars

    Science.gov (United States)

    Fairen, Alberto G.; Dohm, James M.; Baker, Victor R.; Thompson, Shane D.; Mahaney, William C.; Herkenhoff, Kenneth E.; Rodriguez, J. Alexis P.; Davila, Alfonso F.; Schulze-Makuch, Dirk; El Maarry, M. Ramy; Uceda, Esther R.; Amils, Ricardo; Miyamoto, Hirdy; Kim, Kyeong J.; Anderson, Robert C.; McKay, Christopher P.

    2011-01-01

    Six large iron meteorites have been discovered in the Meridiani Planum region of Mars by the Mars Exploration Rover Opportunity in a nearly 25 km-long traverse. Herein, we review and synthesize the available data to propose that the discovery and characteristics of the six meteorites could be explained as the result of their impact into a soft and wet surface, sometime during the Noachian or the Hesperian, subsequently to be exposed at the Martian surface through differential erosion. As recorded by its sediments and chemical deposits, Meridiani has been interpreted to have undergone a watery past, including a shallow sea, a playa, an environment of fluctuating ground water, and/or an icy landscape. Meteorites could have been encased upon impact and/or subsequently buried, and kept underground for a long time, shielded from the atmosphere. The meteorites apparently underwent significant chemical weathering due to aqueous alteration, as indicated by cavernous features that suggest differential acidic corrosion removing less resistant material and softer inclusions. During the Amazonian, the almost complete disappearance of surface water and desiccation of the landscape, followed by induration of the sediments and subsequent differential erosion and degradation of Meridiani sediments, including at least 10–80 m of deflation in the last 3–3.5 Gy, would have exposed the buried meteorites. We conclude that the iron meteorites support the hypothesis that Mars once had a denser atmosphere and considerable amounts of water and/or water ice at and/or near the surface.

  13. Reducing Motional Decoherence in Ion Traps with Surface Science Methods

    Science.gov (United States)

    Haeffner, Hartmut

    2014-03-01

    Many trapped ions experiments ask for low motional heating rates while trapping the ions close to trapping electrodes. However, in practice small ion-electrode distances lead to unexpected high heating rates. While the mechanisms for the heating is still unclear, it is now evident that surface contamination of the metallic electrodes is at least partially responsible for the elevated heating rates. I will discuss heating rate measurements in a microfabricated surface trap complemented with basic surface science studies. We monitor the elemental surface composition of the Cu-Al alloy trap with an Auger spectrometer. After bake-out, we find a strong Carbon and Oxygen contamination and heating rates of 200 quanta/s at 1 MHz trap frequency. After removing most of the Carbon and Oxygen with Ar-Ion sputtering, the heating rates drop to 4 quanta/s. Interestingly, we still measure the decreased heating rate even after the surface oxidized from the background gas throughout a 40-day waiting time in UHV.

  14. Spectroscopic study of surface enhanced Raman scattering of caffeine on borohydride-reduced silver colloids

    Science.gov (United States)

    Chen, Xiaomin; Gu, Huaimin; Shen, Gaoshan; Dong, Xiao; Kang, Jian

    2010-06-01

    The surface enhanced Raman scattering (SERS) of caffeine on borohydride-reduced silver colloids system under different aqueous solution environment has been studied in this paper. The relative intensity of SERS of caffeine significantly varies with different concentrations of sodium chloride and silver particles. However, at too high or too low concentration of sodium chloride and silver particle, the enhancement of SERS spectra is not evident. The SERS spectra of caffeine suggest that the contribution of the charge transfer mechanism to SERS may be dominant. The chloride ions can significantly enhance the efficiency of SERS, while the enhancement is selective, as the efficiency in charge transfer enhancement is higher than in electromagnetic enhancement. Therefore, it can be concluded that the active site of chloride ion locates on the bond between the caffeine and the silver surface. In addition, the SERS spectra of caffeine on borohydride-reduced and citrate-reduced silver colloids are different, which may be due to different states caffeine adsorbed on silver surface under different silver colloids.

  15. Traffic jams reduce hydrolytic efficiency of cellulase on cellulose surface.

    Science.gov (United States)

    Igarashi, Kiyohiko; Uchihashi, Takayuki; Koivula, Anu; Wada, Masahisa; Kimura, Satoshi; Okamoto, Tetsuaki; Penttilä, Merja; Ando, Toshio; Samejima, Masahiro

    2011-09-02

    A deeper mechanistic understanding of the saccharification of cellulosic biomass could enhance the efficiency of biofuels development. We report here the real-time visualization of crystalline cellulose degradation by individual cellulase enzymes through use of an advanced version of high-speed atomic force microscopy. Trichoderma reesei cellobiohydrolase I (TrCel7A) molecules were observed to slide unidirectionally along the crystalline cellulose surface but at one point exhibited collective halting analogous to a traffic jam. Changing the crystalline polymorphic form of cellulose by means of an ammonia treatment increased the apparent number of accessible lanes on the crystalline surface and consequently the number of moving cellulase molecules. Treatment of this bulky crystalline cellulose simultaneously or separately with T. reesei cellobiohydrolase II (TrCel6A) resulted in a remarkable increase in the proportion of mobile enzyme molecules on the surface. Cellulose was completely degraded by the synergistic action between the two enzymes.

  16. Reducing the health impact of infectious agents: the significance of preventive strategies.

    Science.gov (United States)

    Sattar, Syed A

    2007-09-13

    Each year almost 15 million people die of infectious diseases and in all probability this figure is much higher, because in many cases infection is not at all recognized as being the cause of death or its contributory role is not known. There is an increase in the risks posed by infections; the belief in the omnipotence of drugs has not stood the test of time; rather, by adopting a counterstance we risk losing all that we accomplished during the last decades. After all, over the past 40 years we witnessed progress in the development of reliable and affordable anti-infectives and vaccines. As a result of this, today parents have their children vaccinated less often since they are no longer aware of the risks posed by lack of vaccination. This will give rise to the sudden reemergence of certain infectious diseases. And we overlook the fact that by observing basic rules of hygiene (hand hygiene; water decontamination; etc), we could save many lives on this earth. It is becoming increasingly more difficult to treat with antibiotics patients harboring resistant bacterial strains on their skin. Hospitals need surface disinfection to prevent microbes such as Clostridiium difficile or norovirus. The institutional use of alcohol-based hand disinfectants has by now become an accepted practice in North America. But some of these substances have dangerous side effects where humans and the environment are concerned. Our test methods are not always able to evaluate the actual extent of the risks posed.Prevention is accorded greater importance in view of the declining number of therapeutic measures available. But combating pathogenic microorganisms could, in turn, give rise to problems whose nature we cannot at all predict today. We need far greater knowledge of the pathogens and should be less naïve when embracing new technologies, which only seem to solve problems. What will be the long-term implications if the increasing selective pressure exerted on these bacteria induces

  17. Surface Modifying Substances that Reduce Apparent Yeast Cell Hydrophobicity

    Directory of Open Access Journals (Sweden)

    Lisa Colling

    2005-01-01

    Full Text Available Conclusions. Several commercially available compounds were able to block binding of styrene microspheres to yeast. Some of the binding activity appeared to be attributable to mannose-containing surface components. These findings have implications for formulating therapeutic products that might block yeast binding to tissues.

  18. Riparian shrub buffers reduce surface water pollutant loads

    Science.gov (United States)

    W. A. Geyer; C. Barden; K. Mankin; D. Devlin

    2003-01-01

    Surface water resources in Kansas often contain concentrations of pesticides, nutrients, and sediments that are of concern to local citizens. The United States Geological Survey reported in 1999 that 97 percent of streams and 82 percent of lakes in Kansas would not fully support all uses as designated by state statutes (U.S. Geological Survey 1999). Bacteria and...

  19. Social networking strategies that aim to reduce obesity have achieved significant although modest results.

    Science.gov (United States)

    Ashrafian, Hutan; Toma, Tania; Harling, Leanne; Kerr, Karen; Athanasiou, Thanos; Darzi, Ara

    2014-09-01

    The global epidemic of obesity continues to escalate. Obesity accounts for an increasing proportion of the international socioeconomic burden of noncommunicable disease. Online social networking services provide an effective medium through which information may be exchanged between obese and overweight patients and their health care providers, potentially contributing to superior weight-loss outcomes. We performed a systematic review and meta-analysis to assess the role of these services in modifying body mass index (BMI). Our analysis of twelve studies found that interventions using social networking services produced a modest but significant 0.64 percent reduction in BMI from baseline for the 941 people who participated in the studies' interventions. We recommend that social networking services that target obesity should be the subject of further clinical trials. Additionally, we recommend that policy makers adopt reforms that promote the use of anti-obesity social networking services, facilitate multistakeholder partnerships in such services, and create a supportive environment to confront obesity and its associated noncommunicable diseases.

  20. Significant Beneficial Association of High Dietary Selenium Intake with Reduced Body Fat in the CODING Study.

    Science.gov (United States)

    Wang, Yongbo; Gao, Xiang; Pedram, Pardis; Shahidi, Mariam; Du, Jianling; Yi, Yanqing; Gulliver, Wayne; Zhang, Hongwei; Sun, Guang

    2016-01-04

    Selenium (Se) is a trace element which plays an important role in adipocyte hypertrophy and adipogenesis. Some studies suggest that variations in serum Se may be associated with obesity. However, there are few studies examining the relationship between dietary Se and obesity, and findings are inconsistent. We aimed to investigate the association between dietary Se intake and a panel of obesity measurements with systematic control of major confounding factors. A total of 3214 subjects participated in the study. Dietary Se intake was determined from the Willett food frequency questionnaire. Body composition was measured using dual-energy X-ray absorptiometry. Obese men and women had the lowest dietary Se intake, being 24% to 31% lower than corresponding normal weight men and women, classified by both BMI and body fat percentage. Moreover, subjects with the highest dietary Se intake had the lowest BMI, waist circumference, and trunk, android, gynoid and total body fat percentages, with a clear dose-dependent inverse relationship observed in both gender groups. Furthermore, significant negative associations discovered between dietary Se intake and obesity measurements were independent of age, total dietary calorie intake, physical activity, smoking, alcohol, medication, and menopausal status. Dietary Se intake alone may account for 9%-27% of the observed variations in body fat percentage. The findings from this study strongly suggest that high dietary Se intake is associated with a beneficial body composition profile.

  1. Understanding the Role of Wind in Reducing the Surface Mass Balance Estimates over East Antarctica

    Science.gov (United States)

    Das, I.; Scambos, T. A.; Koenig, L.; Creyts, T. T.; Bell, R. E.; van den Broeke, M. R.; Lenaerts, J.; Paden, J. D.

    2014-12-01

    Accurate quantification of surface snow-accumulation over Antarctica is important for mass balance estimates and climate studies based on ice core records. An improved estimate of surface mass balance must include the significant role near-surface wind plays in the sublimation and redistribution of snow across Antarctica. We have developed an empirical model based on airborne radar and lidar observations, and modeled surface mass balance and wind fields to produce a continent-wide prediction of wind-scour zones over Antarctica. These zones have zero to negative surface mass balance, are located over locally steep ice sheet areas (>0.002) and controlled by bedrock topography. The near-surface winds accelerate over these zones, eroding and sublimating the surface snow. This scouring results in numerous localized regions (≤ 200 km2) with reduced surface accumulation. Each year, tens of gigatons of snow on the Antarctic ice sheet are ablated by persistent near-surface katabatic winds over these wind-scour zones. Large uncertainties remain in the surface mass balance estimates over East Antarctica as climate models do not adequately represent the small-scale physical processes that lead to mass loss through sublimation or redistribution over the wind-scour zones. In this study, we integrate Operation IceBridge's snow radar over the Recovery Ice Stream with a series of ice core dielectric and depth-density profiles for improved surface mass balance estimates that reflect the mass loss over the wind-scour zones. Accurate surface mass balance estimates from snow radars require spatially variable depth-density profiles. Using an ensemble of firn cores, MODIS-derived surface snow grain size, modeled accumulation rates and surface temperatures from RACMO2, we assemble spatially variable depth-density profiles and use our mapping of snow density variations to estimate layer mass and net accumulation rates from snow radar layer data. Our study improves the quantification of

  2. Reducing The Light Reflected by Silicon Surface Using ZnO/TS Antireflection Coating

    Science.gov (United States)

    Suhandi, Andi; Tayubi, Yuyu R.; Wibowo, Firmanul C.; Arifin, Pepen; Supriyatman

    2017-07-01

    Zinc Oxide (ZnO) thin films was coated on a texturized silicon (TS) surface using a spincoating technique. The TS layer was prepared by a wet etching method using 20 % KOH solution at temperature of 80°C for 5 minutes. To prepared precursor solution for ZnO layer, zinc acetate dehydrate, 2-methoxyethanol and monoethanolamine are used as a starting material, solvent and stabilizer, respectively. The XRD and SEM measurements confirmed that the thin films grown by spincoating technique have a single oriented crystal plane and homogenous surfaces. From photoluminescence measurement found that the optical band gap of grown films to be 3.44 eV. The optical reflectance of the grown films is characterized by UV-VIS spectrometry show that the presence of anti-reflection coating ZnO/TS is proven to reduce the reflection of solar radiation by silicon surface significantly.

  3. Reducing phosphorus loading of surface water using iron-coated sand

    NARCIS (Netherlands)

    Groenenberg, J.E.; Chardon, W.J.; Koopmans, G.F.

    2013-01-01

    Phosphorus losses from agricultural soils is an important source of P in surface waters leading to surface water quality impairment. In addition to reducing P inputs, mitigation measures are needed to reduce P enrichment of surface waters. Because drainage of agricultural land by pipe drainage is an

  4. Thyroid function appears to be significantly reduced in Space-borne MDS mice

    Science.gov (United States)

    Saverio Ambesi-Impiombato, Francesco; Curcio, Francesco; Fontanini, Elisabetta; Perrella, Giuseppina; Spelat, Renza; Zambito, Anna Maria; Damaskopoulou, Eleni; Peverini, Manola; Albi, Elisabetta

    It is known that prolonged space flights induced changes in human cardiovascular, muscu-loskeletal and nervous systems whose function is regulated by the thyroid gland but, until now, no data were reported about thyroid damage during space missions. We have demonstrated in vitro that, during space missions (Italian Soyuz Mission "ENEIDE" in 2005, Shuttle STS-120 "ESPERIA" in 2007), thyroid in vitro cultured cells did not respond to thyroid stimulating hor-mone (TSH) treatment; they appeared healthy and alive, despite their being in a pro-apopotic state characterised by a variation of sphingomyelin metabolism and consequent increase in ce-ramide content. The insensitivity to TSH was largely due to a rearrangement of specific cell membrane microdomains, acting as platforms for TSH-receptor (TEXUS-44 mission in 2008). To study if these effects were present also in vivo, as part of the Mouse Drawer System (MDS) Tissue Sharing Program, we performed experiments in mice maintained onboard the Interna-tional Space Station during the long-duration (90 days) exploration mission STS-129. After return to earth, the thyroids isolated from the 3 animals were in part immediately frozen to study the morphological modification in space and in part immediately used to study the effect of TSH treatment. For this purpose small fragments of tissue were treated with 10-7 or 10-8 M TSH for 1 hour by using untreated fragments as controls. Then the fragments were fixed with absolute ethanol for 10 min at room temperature and centrifuged for 20 min. at 3000 x g. The supernatants were used for cAMP analysis whereas the pellet were used for protein amount determination and for immunoblotting analysis of TSH-receptor, sphingomyelinase and sphingomyelin-synthase. The results showed a modification of the thyroid structure and also the values of cAMP production after treatment with 10-7 M TSH for 1 hour were significantly lower than those obtained in Earth's gravity. The treatment with TSH

  5. Polyelectrolytes Ability in Reducing Atrazine Concentration in Water: Surface Effects

    NARCIS (Netherlands)

    Mohd Amin, M.F.; Heijman, S.G.J.; Lopes, S.I.C.; Rietveld, L.C.

    2014-01-01

    This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water. The adsorption study was set up using multiple glass vessels with different polymer dosing levels followed by ultrafiltration with

  6. Polyelectrolytes Ability in Reducing Atrazine Concentration in Water: Surface Effects

    NARCIS (Netherlands)

    Mohd Amin, M.F.; Heijman, S.G.J.; Lopes, S.I.C.; Rietveld, L.C.

    2014-01-01

    This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water. The adsorption study was set up using multiple glass vessels with different polymer dosing levels followed by ultrafiltration with

  7. Femtosecond laser surface texturing of titanium as a method to reduce the adhesion of Staphylococcus aureus and biofilm formation

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Alexandre [Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal); Bordeaux University, Institute of Chemistry & Biology of Membranes & Nanoobjects (CBMN UMR 5248, CNRS), European Institute of Chemistry and Biology, 2 Rue Robert Escarpit, 33607 Pessac (France); Elie, Anne-Marie [Bordeaux University, CBMN UMR 5248, CNRS, Bordeaux Science Agro, 1 Rue du G. de Gaulle, 33170 Gradignan (France); Plawinski, Laurent [Bordeaux University, Institute of Chemistry & Biology of Membranes & Nanoobjects (CBMN UMR 5248, CNRS), European Institute of Chemistry and Biology, 2 Rue Robert Escarpit, 33607 Pessac (France); Serro, Ana Paula [Instituto Superior Técnico, Universidade de Lisboa, CQE-Centro de Química Estrutural, Av. Rovisco Pais 1, 1049-001 Lisbon (Portugal); Botelho do Rego, Ana Maria [Instituto Superior Técnico, Universidade de Lisboa, CQFM-Centro de Química-Física Molecular and Institute of Nanoscience and Nanotechnology - IN, Av. Rovisco Pais 1, 1049-001 Lisbon (Portugal); Almeida, Amélia [Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal); Urdaci, Maria C. [Bordeaux University, CBMN UMR 5248, CNRS, Bordeaux Science Agro, 1 Rue du G. de Gaulle, 33170 Gradignan (France); Durrieu, Marie-Christine [Bordeaux University, Institute of Chemistry & Biology of Membranes & Nanoobjects (CBMN UMR 5248, CNRS), European Institute of Chemistry and Biology, 2 Rue Robert Escarpit, 33607 Pessac (France); Vilar, Rui, E-mail: rui.vilar@tecnico.ulisboa.pt [Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal)

    2016-01-01

    Graphical abstract: - Highlights: • The short-term adhesion of Staphylococcus aureus onto femtosecond laser textured surfaces of titanium was investigated. • The laser textured surfaces consist of laser-induced periodic surface structures (LIPSS) and nanopillars. • The laser treatment enhances the hydrophilicity and the surface free energy of the material. • The laser treatment reduces significantly the adhesion of S. aureus and biofilm formation. • Femtosecond laser surface texturing of titanium is a simple and promising method for endowing dental and orthopedic implants with antibacterial properties. - Abstract: The aim of the present work was to investigate the possibility of using femtosecond laser surface texturing as a method to reduce the colonization of Grade 2 Titanium alloy surfaces by Staphylococcus aureus and the subsequent formation of biofilm. The laser treatments were carried out with a Yb:KYW chirped-pulse-regenerative amplification laser system with a central wavelength of 1030 nm and a pulse duration of 500 fs. Two types of surface textures, consisting of laser-induced periodic surface structures (LIPSS) and nanopillars, were produced. The topography, chemical composition and phase constitution of these surfaces were investigated by atomic force microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, micro-Raman spectroscopy, and X-ray diffraction. Surface wettability was assessed by the sessile drop method using water and diiodomethane as testing liquids. The response of S. aureus put into contact with the laser treated surfaces in controlled conditions was investigated by epifluorescence microscopy and scanning electron microscopy 48 h after cell seeding. The results achieved show that the laser treatment reduces significantly the bacterial adhesion to the surface as well as biofilm formation as compared to a reference polished surfaces and suggest that femtosecond laser texturing is a simple and promising method

  8. Reducing interior temperature resulting from solar energy using three-dimensional surface patterns

    Directory of Open Access Journals (Sweden)

    Shiang-Jiun Lin

    2015-05-01

    Full Text Available Excessive solar energy can significantly increase interior temperatures and yield great energy demands for air conditioning. Whereas reducing energy consumptions is very crucial today, this article employs patterned glass technology which incorporates linear patterns throughout the exterior surface of glass to attenuate the solar effect on the interior thermal field based on theoretical and experimental studies. By periodically imposing linearly three-dimensional patterns over the outer surface of window glass, the analytical results indicate that the interior solar heat is able to be reduced, as the surface patterns increase the incident angle and/or decrease the solar energy loading on the patterned glass material. Moreover, the interior solar heat can be strongly affected by the pattern design. According to thermally measured results, the trapezoidal patterned glass having 3-mm-top-edged patterned members yields lower temperature on the interior surface of glass comparing with that for the trapezoidal patterns having 6-mm-top edges. Therefore, making the least non-sloped feature or flat plane appearing on the patterned glass helps decrease the interior temperature resulting from solar energy.

  9. Ab initio modeling of the bonding of benzotriazole corrosion inhibitor to reduced and oxidized copper surfaces.

    Science.gov (United States)

    Kokalj, Anton

    2015-01-01

    The bonding of benzotriazole-an outstanding corrosion inhibitor for copper-on reduced and oxidized copper surfaces is discussed on the basis of density functional theory (DFT) calculations. Calculations reveal that benzotriazole is able to bond with oxide-free and oxidized copper surfaces and on both of them it bonds significantly stronger to coordinatively unsaturated Cu sites. This suggests that benzotriazole is able to passivate the reactive under-coordinated surface sites that are plausible microscopic sites for corrosion attack. Benzotriazole can adsorb in a variety of different forms, yet it forms a strong molecule-surface bond only in deprotonated form. The bonding is even stronger when the deprotonated form is incorporated into organometallic adcomplexes. This is consistent with existing experimental evidence that benzotriazole inhibits corrosion by forming protective organometallic complexes. It is further shown that adsorption of benzotriazole considerably reduces the metal work function, which is a consequence of a large permanent molecular dipole and a properly oriented adsorption structure. It is argued that such a pronounced effect on the work function might be relevant for corrosion inhibition, because it should diminish the anodic corrosion reaction, which is consistent with existing experimental evidence that benzotriazole, although a mixed type inhibitor, predominantly affects the anodic reaction.

  10. Optimization of Fat-Reduced Puff Pastry Using Response Surface Methodology.

    Science.gov (United States)

    Silow, Christoph; Zannini, Emanuele; Axel, Claudia; Belz, Markus C E; Arendt, Elke K

    2017-02-22

    Puff pastry is a high-fat bakery product with fat playing a key role, both during the production process and in the final pastry. In this study, response surface methodology (RSM) was successfully used to evaluate puff pastry quality for the development of a fat-reduced version. The technological parameters modified included the level of roll-in fat, the number of fat layers (50-200) and the final thickness (1.0-3.5 mm) of the laminated dough. Quality characteristics of puff pastry were measured using the Texture Analyzer with an attached Extended Craft Knife (ECK) and Multiple Puncture Probe (MPP), the VolScan and the C-Cell imaging system. The number of fat layers and final dough thickness, in combination with the amount of roll-in fat, had a significant impact on the internal and external structural quality parameters. With technological changes alone, a fat-reduced (≥30%) puff pastry was developed. The qualities of fat-reduced puff pastries were comparable to conventional full-fat (33 wt %) products. A sensory acceptance test revealed no significant differences in taste of fatness or 'liking of mouthfeel'. Additionally, the fat-reduced puff pastry resulted in a significant (p < 0.05) positive correlation to 'liking of flavor' and overall acceptance by the assessors.

  11. Optimization of Fat-Reduced Puff Pastry Using Response Surface Methodology

    Science.gov (United States)

    Silow, Christoph; Zannini, Emanuele; Axel, Claudia; Belz, Markus C. E.; Arendt, Elke K.

    2017-01-01

    Puff pastry is a high-fat bakery product with fat playing a key role, both during the production process and in the final pastry. In this study, response surface methodology (RSM) was successfully used to evaluate puff pastry quality for the development of a fat-reduced version. The technological parameters modified included the level of roll-in fat, the number of fat layers (50–200) and the final thickness (1.0–3.5 mm) of the laminated dough. Quality characteristics of puff pastry were measured using the Texture Analyzer with an attached Extended Craft Knife (ECK) and Multiple Puncture Probe (MPP), the VolScan and the C-Cell imaging system. The number of fat layers and final dough thickness, in combination with the amount of roll-in fat, had a significant impact on the internal and external structural quality parameters. With technological changes alone, a fat-reduced (≥30%) puff pastry was developed. The qualities of fat-reduced puff pastries were comparable to conventional full-fat (33 wt %) products. A sensory acceptance test revealed no significant differences in taste of fatness or ‘liking of mouthfeel’. Additionally, the fat-reduced puff pastry resulted in a significant (p < 0.05) positive correlation to ‘liking of flavor’ and overall acceptance by the assessors. PMID:28231095

  12. Scaling of surface-plasma reactors with a significantly increased energy density for NO conversion.

    Science.gov (United States)

    Malik, Muhammad Arif; Xiao, Shu; Schoenbach, Karl H

    2012-03-30

    Comparative studies revealed that surface plasmas developing along a solid-gas interface are significantly more effective and energy efficient for remediation of toxic pollutants in air than conventional plasmas propagating in air. Scaling of the surface plasma reactors to large volumes by operating them in parallel suffers from a serious problem of adverse effects of the space charges generated at the dielectric surfaces of the neighboring discharge chambers. This study revealed that a conductive foil on the cathode potential placed between the dielectric plates as a shield not only decoupled the discharges, but also increased the electrical power deposited in the reactor by a factor of about forty over the electrical power level obtained without shielding and without loss of efficiency for NO removal. The shield had no negative effect on efficiency, which is verified by the fact that the energy costs for 50% NO removal were about 60 eV/molecule and the energy constant, k(E), was about 0.02 L/J in both the shielded and unshielded cases.

  13. Significantly improving trace thallium removal from surface waters during coagulation enhanced by nanosized manganese dioxide.

    Science.gov (United States)

    Huangfu, Xiaoliu; Ma, Chengxue; Ma, Jun; He, Qiang; Yang, Chun; Jiang, Jin; Wang, Yaan; Wu, Zhengsong

    2017-02-01

    Thallium (Tl) is an element of high toxicity and significant accumulation in human body. There is an urgent need for the development of appropriate strategies for trace Tl removal in drinking water treatment plants. In this study, the efficiency and mechanism of trace Tl (0.5 μg/L) removal by conventional coagulation enhanced by nanosized manganese dioxide (nMnO2) were explored in simulated water and two representative surface waters (a river water and a reservoir water obtained from Northeast China). Experimental results showed that nMnO2 significantly improve Tl(I) removal from selected waters. The removal efficiency was dramatically higher in the simulated water, demonstrating by less than 0.1 μg/L Tl residual. The enhancement of trace Tl removal in the surface waters decreased to a certain extent. Both adjusting water pH to alkaline condition and preoxidation of Tl(I) to Tl(III) benefit trace Tl removal from surface waters. Data also indicated that competitive cation of Ca(2+) decreased the efficiency of trace Tl removal, resulting from the reduction of Tl adsorption on nMnO2. Humic acid could largely low Tl removal efficiency during nMnO2 enhanced coagulation processes. Trace elemental Tl firstly adsorbed on nMnO2 and then removed accompanying with nMnO2 settling. The information obtained in the present study may provide a potential strategy for drinking water treatment plants threatened by trace Tl.

  14. 26 CFR 54.4980F-1 - Notice requirements for certain pension plan amendments significantly reducing the rate of future...

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 17 2010-04-01 2010-04-01 false Notice requirements for certain pension plan... (CONTINUED) PENSION EXCISE TAXES § 54.4980F-1 Notice requirements for certain pension plan amendments... a plan amendment of an applicable pension plan that significantly reduces the rate of future benefit...

  15. Reducing dissolved inorganic nitrogen in surface runoff water from sugarcane production systems.

    Science.gov (United States)

    Webster, A J; Bartley, R; Armour, J D; Brodie, J E; Thorburn, P J

    2012-01-01

    Nitrogen (N) lost from farms, especially as the highly bioavailable dissolved inorganic form, may be damaging Australia's Great Barrier Reef (GBR). As sugarcane is the dominant cropping system in GBR catchments, its N management practises are coming under increasing scrutiny. This study measured dissolved inorganic N lost in surface runoff water and sugarcane productivity over 3 years. The experiment compared the conventional fertiliser N application rate to sugarcane (average 180kg N/ha/year) and a rate based on replacing N exported in the previous crop (average 94kg N/ha/year). Dissolved inorganic N losses in surface water were 72%, 48% and 66% lower in the three monitored years in the reduced N fertiliser treatment. There was no significant difference in sugarcane yield between the two fertiliser N treatments, nor any treatment difference in soil mineral N - both of these results are indicators of the sustainability of the lower fertiliser N applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Wear-reducing Surface Functionalization of Implant Materials Using Ultrashort Laser Pulses

    Science.gov (United States)

    Oldorf, P.; Peters, R.; Reichel, S.; Schulz, A.-P.; Wendlandt, R.

    The aim of the project called "EndoLas" is the development of a reproducible and reliable method for a functionalization of articulating surfaces on hip joint endoprostheses due to a reduction of abrasion and wear by the generation of micro structures using ultrashort laser pulses. On the one hand, the microstructures shall ensure the capture of abraded particles, which cause third-body wear and thereby increase aseptic loosening. On the other hand, the structures shall improve or maintain the tribologically important lubricating film. Thereby, the cavities serve as a reservoir for the body's own synovial fluid. The dry friction, which promotes abrasion and is a part of the mixed friction in the joint, shall therefore be reduced. In experimental setups it was shown, that the abrasive wear can be reduced significantly due to micro-structuring the articulating implant surfaces. To shape the fine and deterministic cavities on the surfaces, an ultra-short pulsed laser, which is integrated in a high-precision, 5-axes micro-machining system, was used. The laser system, based on an Yb:YAG thin-disk regenerative amplifier, has an average output power of 50 W at the fundamental wavelength of 1030 nm, a maximum repetition rate of 400 kHz and a pulse duration of 6 ps. Due to this, a maximum pulse energy of 125 μJ is achievable. Furthermore external second and third harmonic generation enables the usage of wavelengths in the green and violet spectral range.

  17. Biochar-amended filter socks reduce herbicide losses via tile line surface inlets

    Science.gov (United States)

    Standing water in depressions and behind terraces in fields with subsurface drainage systems can result in reduced crop yields. This concern can be partially alleviated by installing surface inlets that reduce the duration of ponding. Unfortunately, these inlets provide an open conduit for surface w...

  18. Dryland, calcareous soils store (and lose) significant quantities of near-surface organic carbon

    Science.gov (United States)

    Cunliffe, Andrew M.; Puttock, Alan K.; Turnbull, Laura; Wainwright, John; Brazier, Richard E.

    2016-04-01

    Semiarid ecosystems are susceptible to changes in dominant vegetation which may have significant implications for terrestrial carbon dynamics. The present study examines the distribution of organic carbon (OC) between particle size fractions in near-surface (0-0.05 m) soil and the water erosion-induced redistribution of particle-associated OC over a grass-shrub ecotone, in a semiarid landscape, subject to land degradation. Coarse (>2 mm) particles have comparable average OC concentrations to the fine (events was monitored over four annual monsoon seasons. Eroded sediment was significantly enriched in OC; enrichment increased significantly across the grass-shrub ecotone and appears to be an enduring phenomenon probably sustained through the dynamic replacement of preferentially removed organic matter. The average erosion-induced OC event yield increased sixfold across the ecotone from grass-dominated to shrub-dominated ecosystems, due to both greater erosion and greater OC enrichment. This erosional pathway is rarely considered when comparing the carbon budgets of grasslands and shrublands, yet this accelerated efflux of OC may be important for long-term carbon storage potentials of dryland ecosystems.

  19. Surface water drainage system. Environmental assessment and finding of no significant impact

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-01

    This Environmental Assessment (EA) is written pursuant to the National Environmental Policy Act (NEPA). The document identifies and evaluates the action proposed to correct deficiencies in, and then to maintain, the surface water drainage system serving the Department of Energy`s Rocky Flats Environmental Technology Site (Site), located north of Golden, Colorado. Many of the activities proposed would not normally be subject to this level of NEPA documentation. However, in many cases, maintenance of the system has been deferred to the point that wetlands vegetation has become established in some ditches and culverts, creating wetlands. The proposed activities would damage or remove some of these wetlands in order to return the drainage system to the point that it would be able to fully serve its intended function - stormwater control. The Department of Energy (DOE) regulations require that activities affecting environmentally sensitive areas like wetlands be the subject of an EA. Most portions of the surface water drainage system are presently inadequate to convey the runoff from a 100-year storm event. As a result, such an event would cause flooding across much of the Site and possibly threaten the integrity of the dams at the terminal ponds. Severe flooding would not only cause damage to facilities and equipment, but could also facilitate the transport of contaminants from individual hazardous substance sites (IHSSs). Uncontrolled flow through the A- and B-series ponds could cause contaminated sediments to become suspended and carried downstream. Additionally, high velocity flood flows significantly increase erosion losses.

  20. Kernel density surface modelling as a means to identify significant concentrations of vulnerable marine ecosystem indicators.

    Directory of Open Access Journals (Sweden)

    Ellen Kenchington

    Full Text Available The United Nations General Assembly Resolution 61/105, concerning sustainable fisheries in the marine ecosystem, calls for the protection of vulnerable marine ecosystems (VME from destructive fishing practices. Subsequently, the Food and Agriculture Organization (FAO produced guidelines for identification of VME indicator species/taxa to assist in the implementation of the resolution, but recommended the development of case-specific operational definitions for their application. We applied kernel density estimation (KDE to research vessel trawl survey data from inside the fishing footprint of the Northwest Atlantic Fisheries Organization (NAFO Regulatory Area in the high seas of the northwest Atlantic to create biomass density surfaces for four VME indicator taxa: large-sized sponges, sea pens, small and large gorgonian corals. These VME indicator taxa were identified previously by NAFO using the fragility, life history characteristics and structural complexity criteria presented by FAO, along with an evaluation of their recovery trajectories. KDE, a non-parametric neighbour-based smoothing function, has been used previously in ecology to identify hotspots, that is, areas of relatively high biomass/abundance. We present a novel approach of examining relative changes in area under polygons created from encircling successive biomass categories on the KDE surface to identify "significant concentrations" of biomass, which we equate to VMEs. This allows identification of the VMEs from the broader distribution of the species in the study area. We provide independent assessments of the VMEs so identified using underwater images, benthic sampling with other gear types (dredges, cores, and/or published species distribution models of probability of occurrence, as available. For each VME indicator taxon we provide a brief review of their ecological function which will be important in future assessments of significant adverse impact on these habitats here

  1. A Recombinant Multi-Stage Vaccine against Paratuberculosis Significantly Reduces Bacterial Level in Tissues without Interference in Diagnostics

    DEFF Research Database (Denmark)

    Jungersen, Gregers; Thakur, Aneesh; Aagaard, C.;

    PCR and revealed significantly reduced levels of Map and reduced histopathology. Diagnostic tests for antibody responses and cell-mediated immune responses, used as surrogates of infection, corroborated the observed vaccine efficacy: Five of seven non‐vaccinated calves seroconverted in ID Screen......-γ assay responses from 40 to 52 weeks compared to non-vaccinated calves. These results indicate the FET11 vaccine can be used to accelerate eradication of paratuberculosis while surveillance or test-and-manage control programs for tuberculosis and Johne’s disease remain in place. Funded by EMIDA ERA...

  2. Femtosecond laser surface texturing of titanium as a method to reduce the adhesion of Staphylococcus aureus and biofilm formation

    Science.gov (United States)

    Cunha, Alexandre; Elie, Anne-Marie; Plawinski, Laurent; Serro, Ana Paula; Botelho do Rego, Ana Maria; Almeida, Amélia; Urdaci, Maria C.; Durrieu, Marie-Christine; Vilar, Rui

    2016-01-01

    The aim of the present work was to investigate the possibility of using femtosecond laser surface texturing as a method to reduce the colonization of Grade 2 Titanium alloy surfaces by Staphylococcus aureus and the subsequent formation of biofilm. The laser treatments were carried out with a Yb:KYW chirped-pulse-regenerative amplification laser system with a central wavelength of 1030 nm and a pulse duration of 500 fs. Two types of surface textures, consisting of laser-induced periodic surface structures (LIPSS) and nanopillars, were produced. The topography, chemical composition and phase constitution of these surfaces were investigated by atomic force microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, micro-Raman spectroscopy, and X-ray diffraction. Surface wettability was assessed by the sessile drop method using water and diiodomethane as testing liquids. The response of S. aureus put into contact with the laser treated surfaces in controlled conditions was investigated by epifluorescence microscopy and scanning electron microscopy 48 h after cell seeding. The results achieved show that the laser treatment reduces significantly the bacterial adhesion to the surface as well as biofilm formation as compared to a reference polished surfaces and suggest that femtosecond laser texturing is a simple and promising method for endowing dental and orthopedic titanium implants with antibacterial properties, reducing the risk of implant-associated infections without requiring immobilized antibacterial substances, nanoparticles or coatings.

  3. Interaction between FOXO1A-209 Genotype and Tea Drinking is Significantly Associated with Reduced Mortality at Advanced Ages

    DEFF Research Database (Denmark)

    Zeng, Yi; Chen, Huashuai; Ni, Ting

    2016-01-01

    at advanced ages. Such significant association is replicated in two independent Han Chinese CLHLS cohorts (p =0.028-0.048 in the discovery and replication cohorts, and p =0.003-0.016 in the combined dataset). We found the associations between tea drinking and reduced mortality are much stronger among carriers...... of the FOXO1A-209 genotype compared to non-carriers, and drinking tea is associated with a reversal of the negative effects of carrying FOXO1A-209 minor alleles, that is, from a substantially increased mortality risk to substantially reduced mortality risk at advanced ages. The impacts are considerably...... gene expression and its biological functions, which reduces the negative impacts of FOXO1A-209 gene on longevity (as reported in the literature) and offers protection against mortality risk at oldest-old ages. Our empirical findings imply that the health outcomes of particular nutritional interventions...

  4. Quantitative radiolarian assemblages in surface sediments from the central Indian Basin and their paleomonsoonal significance

    Digital Repository Service at National Institute of Oceanography (India)

    Gupta, S.M.

    The percentage data of 47 radiolarian coarser taxonomic groups in the surface sediments from the central Indian Basin was subjected to cluster and factor analyses. The R-mode cluster analysis resulted in 3 dominant clusters which represent surface...

  5. Surface Polysaccharide Mutants Reveal that Absence of O Antigen Reduces Biofilm Formation of Actinobacillus pleuropneumoniae.

    Science.gov (United States)

    Hathroubi, S; Hancock, M A; Bossé, J T; Langford, P R; Tremblay, Y D N; Labrie, J; Jacques, M

    2015-10-19

    Actinobacillus pleuropneumoniae is a Gram-negative bacterium belonging to the Pasteurellaceae family and the causative agent of porcine pleuropneumonia, a highly contagious lung disease causing important economic losses. Surface polysaccharides, including lipopolysaccharides (LPS) and capsular polysaccharides (CPS), are implicated in the adhesion and virulence of A. pleuropneumoniae, but their role in biofilm formation is still unclear. In this study, we investigated the requirement for these surface polysaccharides in biofilm formation by A. pleuropneumoniae serotype 1. Well-characterized mutants were used: an O-antigen LPS mutant, a truncated core LPS mutant with an intact O antigen, a capsule mutant, and a poly-N-acetylglucosamine (PGA) mutant. We compared the amount of biofilm produced by the parental strain and the isogenic mutants using static and dynamic systems. Compared to the findings for the biofilm of the parental or other strains, the biofilm of the O antigen and the PGA mutants was dramatically reduced, and it had less cell-associated PGA. Real-time PCR analyses revealed a significant reduction in the level of pgaA, cpxR, and cpxA mRNA in the biofilm cells of the O-antigen mutant compared to that in the biofilm cells of the parental strain. Specific binding between PGA and LPS was consistently detected by surface plasmon resonance, but the lack of O antigen did not abolish these interactions. In conclusion, the absence of the O antigen reduces the ability of A. pleuropneumoniae to form a biofilm, and this is associated with the reduced expression and production of PGA. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  6. Friction-reducing micro/nanoprotrusions on electrodeposited Ni–Co alloy coating surface fabricated by laser direct writing

    Indian Academy of Sciences (India)

    Haifeng Yang; Tianchi Chen; Jiguo Qian; Jing Han; Haidong He; Longpeng Zhou; Enlan Zhao; Wei Tang; Hua Zhu

    2015-02-01

    Ni–Co coating or texturing surface has been studied extensively to improve the anti-friction ability of the surface. In this paper, we combine the advantages of Ni–Co coating and textured surface, and then use a simple, novel and easily controlled method to fabricate a series of micro/nanoprotrusions on the Ni–Co coating surface. The nanotribology properties were characterized by AFM. The result shows that the micro/nanotextured surface significantly reduced the friction forces compared with the original Ni–Co coating surface. The half-ellipsoid patterns have better tribology properties than half-hemispherical patterns. Both laser power and laser scanning speed were found to influence the friction performances.

  7. Effective Medium Theory for Drag Reducing Micro-patterned Surfaces in Turbulent Flows

    CERN Document Server

    Battiato, Ilenia

    2013-01-01

    Inspired by the lotus effect, many studies in the last decade have focused on micro- and nano-patterned surfaces. They revealed that patterns at the micro-scale combined with high contact angles can significantly reduce skin drag. However, the mechanisms and parameters that control drag reduction, e.g. Reynolds number and pattern geometry, are still unclear. We propose an effective medium representation of the micro-features, that treats the latter as a porous medium, and provides a framework to model flow over patterned surfaces in both Cassie and Wenzel states. Our key result is a closed-form expression for the skin friction coefficient in terms of frictional Reynolds (or K\\'arm\\'an) number in turbulent regime, the viscosity ratio between the fluid in and above the features, and their geometrical properties. We apply the proposed model to turbulent flows over superhydrophobic ridged surfaces. The model predictions agree with laboratory experiments for Reynolds numbers ranging from 3000 to 10000.

  8. The potential for Bayesian compressive sensing to significantly reduce electron dose in high-resolution STEM images.

    Science.gov (United States)

    Stevens, Andrew; Yang, Hao; Carin, Lawrence; Arslan, Ilke; Browning, Nigel D

    2014-02-01

    The use of high-resolution imaging methods in scanning transmission electron microscopy (STEM) is limited in many cases by the sensitivity of the sample to the beam and the onset of electron beam damage (for example, in the study of organic systems, in tomography and during in situ experiments). To demonstrate that alternative strategies for image acquisition can help alleviate this beam damage issue, here we apply compressive sensing via Bayesian dictionary learning to high-resolution STEM images. These computational algorithms have been applied to a set of images with a reduced number of sampled pixels in the image. For a reduction in the number of pixels down to 5% of the original image, the algorithms can recover the original image from the reduced data set. We show that this approach is valid for both atomic-resolution images and nanometer-resolution studies, such as those that might be used in tomography datasets, by applying the method to images of strontium titanate and zeolites. As STEM images are acquired pixel by pixel while the beam is scanned over the surface of the sample, these postacquisition manipulations of the images can, in principle, be directly implemented as a low-dose acquisition method with no change in the electron optics or the alignment of the microscope itself.

  9. Reduced brain levels of DHEAS in hepatic coma patients: significance for increased GABAergic tone in hepatic encephalopathy.

    Science.gov (United States)

    Ahboucha, Samir; Talani, Giuseppe; Fanutza, Tomas; Sanna, Enrico; Biggio, Giovanni; Gamrani, Halima; Butterworth, Roger F

    2012-07-01

    Increased neurosteroids with allosteric modulatory activity on GABA(A) receptors such as 3α-5α tertrahydroprogesterone; allopregnanolone (ALLO), are candidates to explain the phenomenon of "increased GABAergic tone" in hepatic encephalopathy (HE). However, it is not known how changes of other GABA(A) receptor modulators such as dehydroepiandrosterone sulfate (DHEAS) contribute to altered GABAergic tone in HE. Concentrations of DHEAS were measured by radioimmunoassay in frontal cortex samples obtained at autopsy from 11 cirrhotic patients who died in hepatic coma and from an equal number of controls matched for age, gender, and autopsy delay intervals free from hepatic or neurological diseases. To assess whether reduced brain DHEAS contributes to increased GABAergic tone, in vitro patch clamp recordings in rat prefrontal cortex neurons were performed. A significant reduction of DHEAS (5.81±0.88 ng/g tissue) compared to control values (9.70±0.79 ng/g, puremic coma (12.56 ng/g tissue) were within the control range. Increasing ALLO enhances GABAergic tonic currents concentration-dependently, but increasing DHEAS reduces these currents. High concentrations of DHEAS (50 μM) reduce GABAergic tonic currents in the presence of ALLO, whereas reduced concentrations of DHEAS (1 μM) further stimulate these currents. These findings demonstrate that decreased concentrations of DHEAS together with increased brain concentrations of ALLO increase GABAergic tonic currents synergistically; suggesting that reduced brain DHEAS could further increase GABAergic tone in human HE. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. The significance of a differential distribution of phosphomonoesterases on bone surfaces after prolonged demineralization

    DEFF Research Database (Denmark)

    Vilmann, H; Kirkeby, S

    1979-01-01

    with the patterns of apposition and resorption on the periosteal surfaces of this bone, revealed by in vivo staining with alizarin red S. Presence of reaction to acid phosphatase is, as shown before, an indication of resorptive surfaces, while the presence of reaction to alkaline phosphatase is an indication...

  11. Hairy suckers: the surface microstructure and its possible functional significance in the Octopus vulgaris sucker

    Directory of Open Access Journals (Sweden)

    Francesca Tramacere

    2014-05-01

    Full Text Available Octopus suckers are able to attach to any smooth surface and many rough surfaces. Here, we have discovered that the sucker surface, which has been hypothesised to be responsible for sealing the orifice during adhesion, is not smooth as previously assumed, but is completely covered by a dense network of hair-like micro-outgrowths. This finding is particularly important because it provides another demonstration of the role of hair-structures in a sealing mechanism in water, similar to that previously described for clingfish and abalones. Moreover, the discovered hairs may provide an additional adhesive mechanism that works in concert with suction. The discovered surface structures might be potentially interesting for biomimetics of novel technical suction cups with improved adhesion capabilities on non-smooth surfaces.

  12. Bio-replicated forming of the biomimetic drag-reducing surfaces in large area based on shark skin

    Institute of Scientific and Technical Information of China (English)

    HAN Xin; ZHANG DeYuan; LI Xiang; LI YuanYue

    2008-01-01

    On the investigation of biomimetic drag-reducing surface, direct replication of the firm scarfskins on low-resistance creatures to form biomimetic drag-reducing surfaces with relatively vivid morphology relative to the living prototype is a new attempt of the bio-replicated forming technology. Taking shark skin as the bio-replication template, the hot embossing method was applied to the micro-replication of its outward morphology. Furthermore, the skins were jointed together to form the drag-reducing sur-face in large area. The results of the resistance measurements in a water tunnel according to the flat-plate sample pieces have shown that the biomimetic shark-skin coating fabricated by the bio-replicated forming method has significant drag reduction effect, and that the drag reduction effi-ciency reached 8.25% in the test conditions.

  13. Lime and Phosphate Amendment Can Significantly Reduce Uptake of Cd and Pb by Field-Grown Rice

    Directory of Open Access Journals (Sweden)

    Rongbo Xiao

    2017-03-01

    Full Text Available Agricultural soils are suffering from increasing heavy metal pollution, among which, paddy soil polluted by heavy metals is frequently reported and has elicited great public concern. In this study, we carried out field experiments on paddy soil around a Pb-Zn mine to study amelioration effects of four soil amendments on uptake of Cd and Pb by rice, and to make recommendations for paddy soil heavy metal remediation, particularly for combined pollution of Cd and Pb. The results showed that all the four treatments can significantly reduce the Cd and Pb content in the late rice grain compared with the early rice, among which, the combination amendment of lime and phosphate had the best remediation effects where rice grain Cd content was reduced by 85% and 61%, respectively, for the late rice and the early rice, and by 30% in the late rice grain for Pb. The high reduction effects under the Ca + P treatment might be attributed to increase of soil pH from 5.5 to 6.7. We also found that influence of the Ca + P treatment on rice production was insignificant, while the available Cd and Pb content in soil was reduced by 16.5% and 11.7%, respectively.

  14. Lipid Replacement Therapy Drink Containing a Glycophospholipid Formulation Rapidly and Significantly Reduces Fatigue While Improving Energy and Mental Clarity

    Directory of Open Access Journals (Sweden)

    Robert Settineri

    2011-08-01

    Full Text Available Background: Fatigue is the most common complaint of patients seeking general medical care and is often treated with stimulants. It is also important in various physical activities of relatively healthy men and women, such as sports performance. Recent clinical trials using patients with chronic fatigue have shown the benefit of Lipid Replacement Therapy in restoring mitochondrial electron transport function and reducing moderate to severe chronic fatigue. Methods: Lipid Replacement Therapy was administered for the first time as an all-natural functional food drink (60 ml containing polyunsaturated glycophospholipids but devoid of stimulants or herbs to reduce fatigue. This preliminary study used the Piper Fatigue Survey instrument as well as a supplemental questionnaire to assess the effects of the glycophospholipid drink on fatigue and the acceptability of the test drink in adult men and women. A volunteer group of 29 subjects of mean age 56.2±4.5 years with various fatigue levels were randomly recruited in a clinical health fair setting to participate in an afternoon open label trial on the effects of the test drink. Results: Using the Piper Fatigue instrument overall fatigue among participants was reduced within the 3-hour seminar by a mean of 39.6% (p<0.0001. All of the subcategories of fatigue showed significant reductions. Some subjects responded within 15 minutes, and the majority responded within one hour with increased energy and activity and perceived improvements in cognitive function, mental clarity and focus. The test drink was determined to be quite acceptable in terms of taste and appearance. There were no adverse events from the energy drink during the study.Functional Foods in Health and Disease 2011; 8:245-254Conclusions: The Lipid Replacement Therapy functional food drink appeared to be a safe, acceptable and potentially useful new method to reduce fatigue, sustain energy and improve perceptions of mental function.

  15. The Significance of High, Isolated, Low-relief Surfaces in Glaciated Mountain Ranges

    Science.gov (United States)

    Brocklehurst, S. H.

    2015-12-01

    The highest regions of glaciated mountain ranges are characterised by cirques, arêtes and steep hillslopes. In addition, though, many ranges exhibit high, isolated, low-relief surfaces, which may provide an important record of landscape evolution. Broad, low-curvature surfaces, for example in the Laramide Ranges of the western United States, reflect periglacial regolith production and transport (e.g., Anderson, 2002). Here, the focus is on smaller surfaces that appear to be out of equilibrium with current/recent surface processes, and are interpreted as former glacial valley floors isolated from the current valley network. The low-relief surfaces at the crest of the Sierra Nevada, California, are diamict covered. The top of Sardine Canyon is a beheaded cirque, while the cirque on the western side of Baxter Pass is in the process of being beheaded. Meanwhile, the isolated patch of diamict on the northeastern ridge of University Peak is surrounded on all sides by steep cliffs, and presumably represents a more evolved surface. It is inferred that the glaciated eastern Sierra Nevada is subject to a cycle of drainage capture and relief inversion, driven by headward erosion by cirque glaciers. The central Himalaya contains a number of low-relief, ice-covered surfaces far above the rest of the glacial valley network (e.g., the Sakyetang Glacier, >6,600m, above the Kazhen Glacier, 6,000m is frozen to the bedrock, so sub-glacial erosion will be outpaced by rock uplift. The extreme relief and active tectonics of the central Himalaya mean that drainage capture is not necessarily required in the generation of high, isolated, low-relief surfaces; glacial steps can become exaggerated to form reconstituted glaciers. High, isolated, low-relief surfaces are found across the Southern Alps, New Zealand, from Miserable Ridge and Kelly Saddle close to the western range front, through Urquhart Peak and Lake Browning near the Main Divide, to Kaimakamaka Peaks east of the Main Divide. As

  16. Covalent Attachment of Poly(ethylene glycol) to Surfaces, Critical for Reducing Bacterial Adhesion

    DEFF Research Database (Denmark)

    Kingshott, Peter; Wei, Jiang; Bagge, Dorthe

    2003-01-01

    on both substrates, as judged by X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Also, ToF-SIMS imaging showed that both substrates were chemically uniform after each surface modification step. Thus, the two surfaces differ only in the mode of attachment...... of PEI to the substrate. In bacterial adhesion experiments, the optimal SS-PEG surface was not capable of reducing the number of adherent Pseudomonas sp. when compared to the controls. However, the PET-PEG surface reduced the level of adhesion by between 2 and 4 orders of magnitude for up to 5 h. ToF-SIMS...... analysis showed that both PEG surfaces adsorbed low but comparable levels of proteinaceous growth medium components (tryptic soy broth), as indicated by the addition of unique amino acid fragment ions in the spectra, most likely small peptides. Thus, bacterial adhesion was strongly dependent on the PEG...

  17. Microbial methanogenesis in the sulfate-reducing zone of surface sediments traversing the Peruvian margin

    Science.gov (United States)

    Maltby, J.; Sommer, S.; Dale, A. W.; Treude, T.

    2016-01-01

    We studied the concurrence of methanogenesis and sulfate reduction in surface sediments (0-25 cm below sea floor) at six stations (70, 145, 253, 407, 990 and 1024 m) along the Peruvian margin (12° S). This oceanographic region is characterized by high carbon export to the seafloor creating an extensive oxygen minimum zone (OMZ) on the shelf, both factors that could favor surface methanogenesis. Sediments sampled along the depth transect traversed areas of anoxic and oxic conditions in the bottom-near water. Net methane production (batch incubations) and sulfate reduction (35S-sulfate radiotracer incubation) were determined in the upper 0-25 cm b.s.f. of multiple cores from all stations, while deep hydrogenotrophic methanogenesis (> 30 cm b.s.f., 14C-bicarbonate radiotracer incubation) was determined in two gravity cores at selected sites (78 and 407 m). Furthermore, stimulation (methanol addition) and inhibition (molybdate addition) experiments were carried out to investigate the relationship between sulfate reduction and methanogenesis.Highest rates of methanogenesis and sulfate reduction in the surface sediments, integrated over 0-25 cm b.s.f., were observed on the shelf (70-253 m, 0.06-0.1 and 0.5-4.7 mmol m-2 d-1, respectively), while lowest rates were discovered at the deepest site (1024 m, 0.03 and 0.2 mmol m-2 d-1, respectively). The addition of methanol resulted in significantly higher surface methanogenesis activity, suggesting that the process was mostly based on non-competitive substrates - i.e., substrates not used by sulfate reducers. In the deeper sediment horizons, where competition was probably relieved due to the decrease of sulfate, the usage of competitive substrates was confirmed by the detection of hydrogenotrophic activity in the sulfate-depleted zone at the shallow shelf station (70 m).Surface methanogenesis appeared to be correlated to the availability of labile organic matter (C / N ratio) and organic carbon degradation (DIC production

  18. Tuning microstructure and surface chemistry of reduced graphene oxide by mild reduction

    Institute of Scientific and Technical Information of China (English)

    冷娴; 刘如铁; 邹俭鹏; 熊翔; 何捍卫

    2016-01-01

    Reduced graphene oxide (RGO) sheets with varied contents and types of oxygenated groups were synthesized by Hummers treatment of natural graphite powders followed by different nontoxic and mild reduction methods, which include thermal and chemical reduction with ethylene glycol, KOH and Fe powder. The changes in microstructure and surface chemistry of RGOs were extensively characterized by SEM, TEM, AFM, XRD, XPS and Raman spectrum. The results show that significant exfoliation occurs during oxidation and is retained in reduction processes, along with the formation of curled wavy morphology. Compared with larged spacing (0.852 nm) of graphene oxide (GO), the (002) plane distance decreases to 0.358−0.384 nm of RGOs, indicating efficient tuning of surface functionalities through mild reduction methods. TheID/IG ratio of RGOs is about 1.0−1.15, indicating that reconstructed sp2 domains have smaller sizes and larger quantity. The content of sp2 bonded C in GO (36.93%, molar fraction) increases to 45.48%−72.92% (molar fraction) in RGOs, along with a drastic decrease in hydroxyl and epoxy and minor changes in carbonyl and carboxyl. Thermal reduction or chemical reduction produces RGOs with residual functionalities, which may render different chemical activity and is desirable in various applications.

  19. Evaluation of the Significance of Starch Surface Binding Sites on Human Pancreatic α-Amylase.

    Science.gov (United States)

    Zhang, Xiaohua; Caner, Sami; Kwan, Emily; Li, Chunmin; Brayer, Gary D; Withers, Stephen G

    2016-11-01

    Starch provides the major source of caloric intake in many diets. Cleavage of starch into malto-oligosaccharides in the gut is catalyzed by pancreatic α-amylase. These oligosaccharides are then further cleaved by gut wall α-glucosidases to release glucose, which is absorbed into the bloodstream. Potential surface binding sites for starch on the pancreatic amylase, distinct from the active site of the amylase, have been identified through X-ray crystallographic analyses. The role of these sites in the degradation of both starch granules and soluble starch was probed by the generation of a series of surface variants modified at each site to disrupt binding. Kinetic analysis of the binding and/or cleavage of substrates ranging from simple maltotriosides to soluble starch and insoluble starch granules has allowed evaluation of the potential role of each such surface site. In this way, two key surface binding sites, on the same face as the active site, are identified. One site, containing a pair of aromatic residues, is responsible for attachment to starch granules, while a second site featuring a tryptophan residue around which a malto-oligosaccharide wraps is shown to heavily influence soluble starch binding and hydrolysis. These studies provide insights into the mechanisms by which enzymes tackle the degradation of largely insoluble polymers and also present some new approaches to the interrogation of the binding sites involved.

  20. Multi-resistive reduced graphene oxide diode with reversible surface electrochemical reaction induced carrier control.

    Science.gov (United States)

    Seo, Hyungtak; Ahn, Seungbae; Kim, Jinseo; Lee, Young-Ahn; Chung, Koo-Hyun; Jeon, Ki-Joon

    2014-07-10

    The extended application of graphene-based electronic devices requires a bandgap opening in order to realize the targeted device functionality. Since the bandgap tuning of pristine graphene is limited to 360 meV, the chemical modification of graphene is considered essential to achieve a large bandgap opening at the expense of electrical properties degradation. Reduced graphene oxide (RGO) has attracted significant interest for fabricating graphene-based semiconductors since it has several advantages over other forms of chemically modified graphene; such as tunable bandgap opening, decent electrical properties, and easy synthesis. Because of the reduced bonding nature of RGO, the role of metastable oxygen in the RGO matrix is recently highlighted and it may offer emerging ionic devices. In this study, we show that multi-resistivity RGO/n-Si diodes can be obtained by controlling the RGO thickness at a nanometer scale. This is made possible by (1) a metastable lattice-oxygen drift within bulk RGO and (2) electrochemical ambient hydroxyl (OH) formation at the RGO surface. The effect demonstrated in a p-RGO/n-Si heterojunction diode is equivalent to electrochemically driven reversible electronic manipulation and therefore provides an important basis for the application of O bistability in RGO for chemical sensors and electrocatalysis.

  1. Campylobacter jejuni cocultured with epithelial cells reduces surface capsular polysaccharide expression.

    LENUS (Irish Health Repository)

    Corcionivoschi, N

    2012-02-01

    The host cell environment can alter bacterial pathogenicity. We employed a combination of cellular and molecular techniques to study the expression of Campylobacter jejuni polysaccharides cocultured with HCT-8 epithelial cells. After two passages, the amount of membrane-bound high-molecular-weight polysaccharide was considerably reduced. Microarray profiling confirmed significant downregulation of capsular polysaccharide (CPS) locus genes. Experiments using conditioned media showed that sugar depletion occurred only when the bacterial and epithelial cells were cocultured. CPS depletion occurred when C. jejuni organisms were exposed to conditioned media from a different C. jejuni strain but not when exposed to conditioned media from other bacterial species. Proteinase K or heat treatment of conditioned media under coculture conditions abrogated the effect on the sugars, as did formaldehyde fixation and cycloheximide treatment of host cells or chloramphenicol treatment of the bacteria. However, sugar depletion was not affected in flagellar export (fliQ) and quorum-sensing (luxS) gene mutants. Passaged C. jejuni showed reduced invasiveness and increased serum sensitivity in vitro. C. jejuni alters its surface polysaccharides when cocultured with epithelial cells, suggesting the existence of a cross talk mechanism that modulates CPS expression during infection.

  2. Influence of hydrophobic and superhydrophobic surfaces on reducing aerodynamic insect residues

    Science.gov (United States)

    Krishnan, K. Ghokulla; Milionis, Athanasios; Loth, Eric; Farrell, Thomas E.; Crouch, Jeffrey D.; Berry, Douglas H.

    2017-01-01

    Insect fouling during takeoff, climb and landing can result in increased drag and fuel consumption for aircrafts with laminar-flow surfaces. This study investigates the effectiveness of various hydrophobic and superhydrophobic surfaces in reducing residue of insects on an aerodynamic surface at relatively high impact speeds (about 45 m/s). An experimental setup consisting of a wind tunnel and a method to inject live flightless fruit flies was used to test the effectiveness of various surfaces against insect fouling. Insect fouling was analyzed based on residue area and height from multiple impacts. In general most of the residue area was due to the hemolymph spreading while most of the residue height was due to adhesion of exoskeleton parts. Hydrophobic and especially superhydrophobic surfaces performed better than a hydrophilic aluminum surface in terms of minimizing the residue area of various insect components (exoskeleton, hemolymph, and red fluid). Surfaces with reduced wettability and short lateral length scales tended to have the smallest residue area. Residue height was not as strongly influenced by surface wettability since even a single exoskeleton adhered to the surface upon impact was enough to produce a residue height of the order of one mm. In general, the results indicate that hemolymph spread needs to be avoided (e.g. by having reduced wettability and short lateral correlation lengths) in order to minimize the residue area, while exoskeleton adherence needs to be avoided (e.g. by having oleophobic properties and micro/nano roughness) in order to minimize the residue height. In particular, two of the superhydrophobic coatings produced substantial reduction in residue height and area, relative to the baseline surface of aluminum. However, the surfaces also showed poor mechanical durability on the high-speed insect impact location. This suggests that although low wettability materials show great insect anti-fouling behavior, their durability needs to

  3. ZnO nanowire/reduced graphene oxide nanocomposites for significantly enhanced photocatalytic degradation of Rhodamine 6G

    Science.gov (United States)

    Zhang, Chao; Zhang, Jing; Su, Yanjie; Xu, Minghan; Yang, Zhi; Zhang, Yafei

    2014-02-01

    We have demonstrated a facile and low-cost approach to synthesize ZnO nanowire (NW)/reduced graphene oxide (RGO) nanocomposites, in which ZnO NWs and graphene oxide (GO) were produced in large scale separately and then hybridized into ZnO NW/RGO nanocomposites by mechanical mixing and low-temperature thermal reduction. Rhodamine 6G (Rh6G) was used as a model dye to evaluate the photocatalytic properties of ZnO NW/RGO nanocomposites. The obtained nanocomposites show significantly enhanced photocatalytic performance, which took only 10 min to decompose over 98% Rh6G. Finally the mechanism of the great enhancement about photocatalytic activity of ZnO NW/RGO nanocomposites is studied. It is mainly attributed to that RGO nanosheets can transfer the electrons of ZnO NWs excited by ultraviolet (UV) irradiation, increase electron migration efficiency, and then longer the lifetime of the holes in ZnO NWs. The high charge separation efficiency of photo-generated electron-hole pairs directly leads to the lower recombination rate of ZnO NW/RGO nanocomposites, makes more effective electrons and holes to participate the radical reactions with Rh6G, thus significantly improving the photocatalytic properties. The high degradation efficiency makes the ZnO NW/RGO nanocomposites promising candidates in the application of environmental pollutant and wastewater treatment.

  4. Walking with a four wheeled walker (rollator) significantly reduces EMG lower-limb muscle activity in healthy subjects.

    Science.gov (United States)

    Suica, Zorica; Romkes, Jacqueline; Tal, Amir; Maguire, Clare

    2016-01-01

    To investigate the immediate effect of four-wheeled- walker(rollator)walking on lower-limb muscle activity and trunk-sway in healthy subjects. In this cross-sectional design electromyographic (EMG) data was collected in six lower-limb muscle groups and trunk-sway was measured as peak-to-peak angular displacement of the centre-of-mass (level L2/3) in the sagittal and frontal-planes using the SwayStar balance system. 19 subjects walked at self-selected speed firstly without a rollator then in randomised order 1. with rollator 2. with rollator with increased weight-bearing. Rollator-walking caused statistically significant reductions in EMG activity in lower-limb muscle groups and effect-sizes were medium to large. Increased weight-bearing increased the effect. Trunk-sway in the sagittal and frontal-planes showed no statistically significant difference between conditions. Rollator-walking reduces lower-limb muscle activity but trunk-sway remains unchanged as stability is likely gained through forces generated by the upper-limbs. Short-term stability is gained but the long-term effect is unclear and requires investigation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Phonon transport in silicon nanowires: The reduced group velocity and surface-roughness scattering

    Science.gov (United States)

    Zhu, Liyan; Li, Baowen; Li, Wu

    2016-09-01

    Using a linear-scaling Kubo simulation approach, we have quantitatively investigated the effects of confinement and surface roughness on phonon transport in silicon nanowires (SiNWs) as thick as 55 nm in diameter R . The confinement effect leads to significant reduction of phonon group velocity v in SiNWs compared to bulk silicon except at extremely low phonon frequencies f , which very likely persists in SiNWs several hundreds of nanometers thick, suggesting the inapplicability of bulk properties, including anharmonic phonon scattering, to SiNWs. For instance, the velocity can be reduced by more than 30% for phonons with f >4.5 THz in 55-nm-thick nanowires. In rough SiNWs Casimir's limit, which is valid in confined macroscopic systems, can underestimate the surface scattering by more than one order of magnitude. For a roughness profile with Lorentzian correlation characterized by root-mean-square roughness σ and correlation length Lr, the frequency-dependent phonon diffusivity D follows power-law dependences D ∝Rασ-βLrγ , where α ˜2 and β ˜1 . On average, γ increases from 0 to 0.5 as R /σ increases. The mean free path and the phonon lifetime essentially follow the same power-law dependences. These dependences are in striking contrast to Casimir's limit, i.e., D ˜v R /3 , and manifest the dominant role of the change in the number of atoms due to roughness. The thermal conductivity κ can vary by one order of magnitude with varying σ and Lr in SiNWs, and increasing σ and shortening Lr can efficiently lower κ below Casimir's limit by one order of magnitude. Our work provides different insights to understand the ultralow thermal conductivity of SiNWs reported experimentally and guidance to manipulate κ via surface roughness engineering.

  6. Modest hypoxia significantly reduces triglyceride content and lipid droplet size in 3T3-L1 adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Takeshi, E-mail: thashimo@fc.ritsumei.ac.jp [Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577 (Japan); Yokokawa, Takumi; Endo, Yuriko [Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577 (Japan); Iwanaka, Nobumasa [Ritsumeikan Global Innovation Research Organization, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577 (Japan); Higashida, Kazuhiko [Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577 (Japan); Faculty of Sport Science, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama 359-1192 (Japan); Taguchi, Sadayoshi [Faculty of Sport and Health Science, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu, Shiga 525-8577 (Japan)

    2013-10-11

    Highlights: •Long-term hypoxia decreased the size of LDs and lipid storage in 3T3-L1 adipocytes. •Long-term hypoxia increased basal lipolysis in 3T3-L1 adipocytes. •Hypoxia decreased lipid-associated proteins in 3T3-L1 adipocytes. •Hypoxia decreased basal glucose uptake and lipogenic proteins in 3T3-L1 adipocytes. •Hypoxia-mediated lipogenesis may be an attractive therapeutic target against obesity. -- Abstract: Background: A previous study has demonstrated that endurance training under hypoxia results in a greater reduction in body fat mass compared to exercise under normoxia. However, the cellular and molecular mechanisms that underlie this hypoxia-mediated reduction in fat mass remain uncertain. Here, we examine the effects of modest hypoxia on adipocyte function. Methods: Differentiated 3T3-L1 adipocytes were incubated at 5% O{sub 2} for 1 week (long-term hypoxia, HL) or one day (short-term hypoxia, HS) and compared with a normoxia control (NC). Results: HL, but not HS, resulted in a significant reduction in lipid droplet size and triglyceride content (by 50%) compared to NC (p < 0.01). As estimated by glycerol release, isoproterenol-induced lipolysis was significantly lowered by hypoxia, whereas the release of free fatty acids under the basal condition was prominently enhanced with HL compared to NC or HS (p < 0.01). Lipolysis-associated proteins, such as perilipin 1 and hormone-sensitive lipase, were unchanged, whereas adipose triglyceride lipase and its activator protein CGI-58 were decreased with HL in comparison to NC. Interestingly, such lipogenic proteins as fatty acid synthase, lipin-1, and peroxisome proliferator-activated receptor gamma were decreased. Furthermore, the uptake of glucose, the major precursor of 3-glycerol phosphate for triglyceride synthesis, was significantly reduced in HL compared to NC or HS (p < 0.01). Conclusion: We conclude that hypoxia has a direct impact on reducing the triglyceride content and lipid droplet size via

  7. Carbon isotopic record of foraminifers in surface sediments from the South China Sea and its significance

    Institute of Scientific and Technical Information of China (English)

    CHENG Xinrong; WANG Pinxian; HUANG Baoqi; LIU Chuanlian; JIAN Zhimin; ZHAO Quanhong; LI Jianru; TIAN Jun; XU Jian

    2005-01-01

    The study is based on stable carbon isotopic measurements of 112 foraminiferal samples from surface sediments at 40 sites in the South China Sea (SCS).δ13C of foraminifers and △δ13C between planktonic and benthic foraminiferal species exhibit a low value area at the northeastern and southern ends of the SCS. It is correlated with the nutrient distributional pattern in the SCS and circumjacent area, the influence of the northeastern and southwestern monsoons on water flow and water chemistry in the SCS. The monsoons have not only brought nutrients to the upper part of the sea but also disturbed water and decreased difference between the surface and bottom water. Its influence is most obvious at both ends, which resulted in the low value areas in δ13C and △δ13C at the ends. The distributional pattern of the stable carbon isotope in the SCS is a reflection of the East Asian monsoons.

  8. Mineral magnetic properties of surface sediments at Bei'anhe, Beijing, and its environmental significance

    Institute of Scientific and Technical Information of China (English)

    WANG HongQiang; ZHANG ShiHong; LI HaiYan

    2008-01-01

    A multiparameter investigation of surface sediments from the Bei'anhe section (Beljing) has been con-ducted using environmental magnetic approaches.The studied sedimentary sequence consists of pluvial and lacustrine silts and clay of the Holocene age.Magnetite,hematite and pyrrhotite were iden-tified as the dominant magnetic minerals.The mineral magnetic characteristics are considered to re-flect the Holocene paleoenvironmental processes of the studied area,which are different from the mineral magnetic properties of typical polluted sections reported in the Beijing area.The low-field magnetic susceptibility and saturated isothermal remanence magnetization of the section decrease gradually with increasing depth.This indicates that the concentration of magnetic minerals in the strata decreases down the section.Values of interparametric ratios,such as ARMISlRM,XARM/X and SIRM/X,gradually increase with increasing depth,which indicates a down-section decreasing trend in the magnetic grain size of the sediments.Pyrrhotite occurs below the depth of 22 cm,suggesting the ex-istence of redox interface.The magnetic variations of the Bei'anhe surface sediments might be con-trolled by two geological processes:reductive diagenesis and pedogenesis.Our findings may have provided a reference point for magnetic investigation of polluted surface sediments in the Beijing area.

  9. Tectonic significance of paleobotanically estimated climate and altitude of the late Eocene erosion surface, Colorado

    Science.gov (United States)

    Gregory, Kathryn M.; Chase, Clement G.

    1992-07-01

    Erosion beveled the Laramide Front Range uplift in Colorado to a surface of low relief by the end of the Eocene. This study uses J. A. Wolfe's new multivariate climate analysis techniques to determine the paleoelevation of this regional surface by examining the overlying 35 Ma Florissant flora. A multiple regression model explaining 93.3% of the variance in mean annual temperature was developed using Wolfe's dataset of 31 leaf physiognomic character states for 86 modern vegetation sites. These character states were scored on 29 species collected from one facies of the Florissant Lake Beds. The paleotemperature estimate of mean annual temperature (10.7 ±1.5 °C) derived from these data, when combined with sea-level temperature and terrestrial lapse rate, implies a late Eocene paleoelevation of 2.4-2.7 km. Pliocene uplift is thus not required to explain the present elevation of 2.5 km. It is unclear when and why the southern Rocky Mountains achieved this elevation. Magmatic crustal thickening can explain the late Eocene high elevation of the southern Rockies, but neither this mechanism nor compressive thickening explains why the Great Plains, which are tied to the Florissant elevation by the Wall Mountain Tuff, were also high. This paleoelevation estimate indicates that regional surfaces of planation could be formed at high elevation in the Eocene, probably because of peculiarities of the Eocene climate.

  10. Filtrate of Phellinus linteus Broth Culture Reduces Infarct Size Significantly in a Rat Model of Permanent Focal Cerebral Ischemia.

    Science.gov (United States)

    Suzuki, Sakiko; Kawamata, Takakazu; Okada, Yoshikazu; Kobayashi, Tomonori; Nakamura, Tomoyuki; Hori, Tomokatsu

    2011-01-01

    Phellinus linteus, a natural growing mushroom, has been known to exhibit anti-tumor, anti-inflammatory, anti-allergic and anti-oxidant effects. Aiming to exploit the neuroprotective effects of P. linteus, we evaluated its effects on infarct volume reduction in a rat model of focal cerebral ischemia. Male Sprague-Dawley rats were subjected to right middle cerebral artery occlusion. Filtrate of P. linteus broth culture (various doses), fractionated filtrate (based on molecular weight) or control medium was administered intraperitoneally to rats before or after ischemia induction. Rats were killed at 24 h after the stroke surgery. Cortical and caudoputaminal infarct volumes were determined separately using an image analysis program following staining with 2,3,5-triphenyltetrazolium chloride. Significant cortical infarct volume reductions were found in the pre-treatment groups (30 and 60 minutes before onset of cerebral ischemia) compared with the control group, showing dose dependence. Posttreatment (30 minutes after ischemic onset) also significantly reduced cortical infarct volume. Furthermore, the higher molecular weight (≥12 000) fraction of the culture filtrate was more effective compared with the lower molecular weight fraction. The present findings suggest that P. linteus may be a new promising approach for the treatment of focal cerebral ischemia, with the additional benefit of a wide therapeutic time window since significant infarct volume reduction is obtained by administration even after the ischemic event. Our finding that the higher molecular weight fraction of the P. linteus culture filtrate demonstrated more prominent effect may provide a clue to identify the neuroprotective substances and mechanisms.

  11. Filtrate of Phellinus linteus Broth Culture Reduces Infarct Size Significantly in a Rat Model of Permanent Focal Cerebral Ischemia

    Directory of Open Access Journals (Sweden)

    Sakiko Suzuki

    2011-01-01

    Full Text Available Phellinus linteus, a natural growing mushroom, has been known to exhibit anti-tumor, anti-inflammatory, anti-allergic and anti-oxidant effects. Aiming to exploit the neuroprotective effects of P. linteus, we evaluated its effects on infarct volume reduction in a rat model of focal cerebral ischemia. Male Sprague-Dawley rats were subjected to right middle cerebral artery occlusion. Filtrate of P. linteus broth culture (various doses, fractionated filtrate (based on molecular weight or control medium was administered intraperitoneally to rats before or after ischemia induction. Rats were killed at 24 h after the stroke surgery. Cortical and caudoputaminal infarct volumes were determined separately using an image analysis program following staining with 2,3,5-triphenyltetrazolium chloride. Significant cortical infarct volume reductions were found in the pre-treatment groups (30 and 60 minutes before onset of cerebral ischemia compared with the control group, showing dose dependence. Posttreatment (30 minutes after ischemic onset also significantly reduced cortical infarct volume. Furthermore, the higher molecular weight (≥12 000 fraction of the culture filtrate was more effective compared with the lower molecular weight fraction. The present findings suggest that P. linteus may be a new promising approach for the treatment of focal cerebral ischemia, with the additional benefit of a wide therapeutic time window since significant infarct volume reduction is obtained by administration even after the ischemic event. Our finding that the higher molecular weight fraction of the P. linteus culture filtrate demonstrated more prominent effect may provide a clue to identify the neuroprotective substances and mechanisms.

  12. The effect of reduced sodium chloride content on the microbiological and biochemical properties of a soft surface-ripened cheese.

    Science.gov (United States)

    Dugat-Bony, E; Sarthou, A-S; Perello, M-C; de Revel, G; Bonnarme, P; Helinck, S

    2016-04-01

    Many health authorities have targeted salt reduction in food products as a means to reduce dietary sodium intake due to the harmful effects associated with its excessive consumption. In the present work, we evaluated the effect of reducing sodium chloride (NaCl) content on the microbiological and biochemical characteristics of an experimental surface-ripened cheese. A control cheese (1.8% NaCl) and a cheese with a reduced NaCl content (1.3% NaCl) were sampled weekly over a period of 27d. Reducing NaCl content induced microbial perturbations such as the lesser development of the yeast Debaryomyces hansenii and the greater development of the gram-negative bacterium Hafnia alvei. This was accompanied by changes in proteolytic kinetics and in profiles of volatile aroma compounds and biogenic amine production. Finally, the development of the spoilage microorganism Pseudomonas fragi was significantly higher in the cheese with a reduced salt content.

  13. The Structure of the Stoichiometric and Reduced $SnO_{2}$ (110) Surface

    CERN Document Server

    Manassidis, I; Kantorovich, L V; Gillan, M J

    1995-01-01

    First-principles calculations based on density functional theory (DFT) and the pseudopotential method have been used to study the stoichiometric and reduced SnO2 (110) surface. The ionic relaxations are found to be moderate for both the stoichiometric and reduced surfaces, and are very similar to those found in recent DFT-pseudopotential work on TiO2. Removal of neutral oxygen leaves two electrons per oxygen on the surface, which are distributed in channels passing through bridging oxygen sites. The associated electron density can be attributed to reduction of tin from Sn4+ to Sn2+, but only if the charge distribution on Sn2+ is recognized to be highly asymmetric. Reduction of the surface gives rise to a broad distribution of gap states, in qualitative agreement with spectroscopic measurements.

  14. Distributions of surface sediments surrounding the Antarctic Peninsula and its environmental significance

    Institute of Scientific and Technical Information of China (English)

    WANG Chunjuan; CHEN Zhihua; LI Chunshun; DU Dewen; YAN Shijuan; ZHU Zhiwei

    2014-01-01

    We analyzed grain size composition to provide information on the types and distributions as well as depositional varieties of marine surface sediments from the area surrounding the Antarctic Peninsula. The samples retrieved from the study area contain gravel, sand, silt and clay. As suggested by bathymetry and morphology, the study area is characterized by neritic, hemipelagic and pelagic deposits. The glacial-marine sediments can be divided into two types, residual paratill and compound paratill, which are primarily transported by glaciers and as ice-rafted debris. Ocean current effects on deposition are more obvious, and the deposit types are distributed consistently with terrain variations.

  15. Probing environmentally significant surface radicals: Crystallographic and temperature dependent adsorption of phenol on ZnO

    Science.gov (United States)

    Thibodeaux, Chad A.; Poliakoff, E.D.; Kizilkaya, Orhan; Patterson, Matthew C.; DiTusa, Mark F.; Kurtz, Richard L.

    2015-01-01

    Environmentally persistent free radicals (EPFRs) are toxic organic/metal oxide composite particles that have been discovered to form from substituted benzenes chemisorbed to metal oxides. Here, we perform photoelectron spectroscopy, electron energy loss spectroscopy, and low energy electron diffraction of phenol chemisorbed to ZnO(1 0 1̱ 0) and (0 0 0 1̱)-Zn to observe electronic structure changes and charge transfer as a function adsorption temperature. We show direct evidence of charge transfer from the ZnO surfaces to the phenol. This evidence can help gain a better understanding of EPFRs and be used to develop possible future remediation strategies. PMID:26388650

  16. Surface grafting of carboxylic groups onto thermoplastic polyurethanes to reduce cell adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Alves, P., E-mail: palves@eq.uc.pt [CIEPQPF, Departamento de Engenharia Química, Universidade de Coimbra, Polo II, Pinhal de Marrocos, 3030-790 Coimbra (Portugal); Ferreira, P. [CIEPQPF, Departamento de Engenharia Química, Universidade de Coimbra, Polo II, Pinhal de Marrocos, 3030-790 Coimbra (Portugal); Kaiser, Jean-Pierre [EMPA, St. Gallen, Lerchenfeldstrasse 5, CH-9014 St. Gallen (Switzerland); Salk, Natalie [Mikrofertigung – Micro Engineering, Fraunhofer IFAM, Wiener Strasse 12, D-288359 Bremen (Germany); Bruinink, Arie [EMPA, St. Gallen, Lerchenfeldstrasse 5, CH-9014 St. Gallen (Switzerland); Sousa, Hermínio C. de; Gil, M.H. [CIEPQPF, Departamento de Engenharia Química, Universidade de Coimbra, Polo II, Pinhal de Marrocos, 3030-790 Coimbra (Portugal)

    2013-10-15

    The interaction of polymers with other materials is an important issue, being their surface properties clearly crucial. For some important polymer applications, their surfaces have to be modified. Surface modification aims to tailor the surface characteristics of a material for a specific application without affecting its bulk properties. Materials can be surface modified by using biological, chemical or physical methods. The aim of this work was to improve the reactivity of the thermoplastic polyurethane (TPU) material (Elastollan{sup ®}) surface and to make its surface cell repellent by grafting carboxylic groups onto its surface. Two TPU materials were studied: a polyether-based TPU and a polyester-based TPU. The grafting efficiency was evaluated by contact angle measurements and by analytical determination of the COOH groups. Scanning electron microscopy (SEM) of the membranes surface was performed as well as cell adhesion tests. It was proved that the surfaces of the TPUs membranes were successfully modified and that cell adhesion was remarkably reduced.

  17. New Variance-Reducing Methods for the PSD Analysis of Large Optical Surfaces

    Science.gov (United States)

    Sidick, Erkin

    2010-01-01

    Edge data of a measured surface map of a circular optic result in large variance or "spectral leakage" behavior in the corresponding Power Spectral Density (PSD) data. In this paper we present two new, alternative methods for reducing such variance in the PSD data by replacing the zeros outside the circular area of a surface map by non-zero values either obtained from a PSD fit (method 1) or taken from the inside of the circular area (method 2).

  18. Concentration and environmental significance of lead in surface snow of Antarctic ice sheet (III)

    Institute of Scientific and Technical Information of China (English)

    秦大河; 任贾文; 孙俊英; 陈瓞延; 文克玲; 李良权

    1995-01-01

    Lead as an ultra-trace heavy metal becomes one of popular topics in glaciochemistry of the Antarctic ice sheet, because of its very low concertration (pg·g-1) and background and its sensitivity to the quality of the environment. The lead concentration of surface snow of the Antarctic ice sheet (corresponding to modern precipitation) applying LEAF technique by Chinese scholars has systematically been studied for the first time in the world. The distribution principle of lead concentration of surface snow of the Antarctic ice sheet is "low in the west and high in the east" along the route of 1990 International Trans-Antarctic Expedition (ITAE). The concentration of lead in East Antarctica is 2 - 3 fold higher than that in Larsen ice shelf and Antarctic Peninsula, which majorly results from the activity of pre-Soviet Antarctic Expedition The concentration of lead in Larsen ice shelf and Antarctic Peninsula can be regarded as the background value of modern precipitation of the Antarctic ice sheet in the en

  19. Taurolidine-citrate lock solution (TauroLock significantly reduces CVAD-associated grampositive infections in pediatric cancer patients

    Directory of Open Access Journals (Sweden)

    Fleischhack Gudrun

    2008-07-01

    Full Text Available Abstract Background Taurolidin/Citrate (TauroLock™, a lock solution with broad spectrum antimicrobial activity, may prevent bloodstream infection (BSI due to coagulase-negative staphylococci (CoNS or 'MRSE' in case of methicillin-resistant isolates in pediatric cancer patients with a long term central venous access device (CVAD, Port- or/Broviac-/Hickman-catheter type. Methods In a single center prospective 48-months cohort study we compared all patients receiving anticancer chemotherapy from April 2003 to March 2005 (group 1, heparin lock with 200 IU/ml sterile normal saline 0.9%; Canusal® Wockhardt UK Ltd, Wrexham, Wales and all patients from April 2005 to March 2007 (group 2; taurolidine 1.35%/Sodium Citrate 4%; TauroLock™, Tauropharm, Waldbüttelbrunn, Germany. Results In group 1 (heparin, 90 patients had 98 CVAD in use during the surveillance period. 14 of 30 (47% BSI were 'primary Gram positive BSI due to CoNS (n = 4 or MRSE (n = 10' [incidence density (ID; 2.30 per 1000 inpatient CVAD-utilization days]. In group 2 (TauroLock™, 89 patients had 95 CVAD in use during the surveillance period. 3 of 25 (12% BSI were caused by CoNS. (ID, 0.45. The difference in the ID between the two groups was statistically significant (P = 0.004. Conclusion The use of Taurolidin/Citrate (TauroLock™ significantly reduced the number and incidence density of primary catheter-associated BSI due to CoNS and MRSE in pediatric cancer patients.

  20. A process to enhance the specific surface area and capacitance of hydrothermally reduced graphene oxide

    KAUST Repository

    Alazmi, Amira

    2016-08-26

    The impact of post-synthesis processing in reduced graphene oxide materials for supercapacitor electrodes has been analyzed. A comparative study of vacuum, freeze and critical point drying was carried out for hydrothermally reduced graphene oxide demonstrating that the optimization of the specific surface area and preservation of the porous network are critical to maximize its supercapacitance performance. As described below, using a supercritical fluid as the drying medium, unprecedented values of the specific surface area (364 m2 g−1) and supercapacitance (441 F g−1) for this class of materials have been achieved.

  1. Optical trapping of nanoparticles with significantly reduced laser powers by using counter-propagating beams (Presentation Recording)

    Science.gov (United States)

    Zhao, Chenglong; LeBrun, Thomas W.

    2015-08-01

    Gold nanoparticles (GNP) have wide applications ranging from nanoscale heating to cancer therapy and biological sensing. Optical trapping of GNPs as small as 18 nm has been successfully achieved with laser power as high as 855 mW, but such high powers can damage trapped particles (particularly biological systems) as well heat the fluid, thereby destabilizing the trap. In this article, we show that counter propagating beams (CPB) can successfully trap GNP with laser powers reduced by a factor of 50 compared to that with a single beam. The trapping position of a GNP inside a counter-propagating trap can be easily modulated by either changing the relative power or position of the two beams. Furthermore, we find that under our conditions while a single-beam most stably traps a single particle, the counter-propagating beam can more easily trap multiple particles. This (CPB) trap is compatible with the feedback control system we recently demonstrated to increase the trapping lifetimes of nanoparticles by more than an order of magnitude. Thus, we believe that the future development of advanced trapping techniques combining counter-propagating traps together with control systems should significantly extend the capabilities of optical manipulation of nanoparticles for prototyping and testing 3D nanodevices and bio-sensing.

  2. Distribution of surface rupture associated the 2016 Kumamoto earthquake and its significance

    Science.gov (United States)

    Goto, H.; Kumahara, Y.; Tsutsumi, H.; Toda, S.; Ishimura, D.; Okada, S.; Nakata, T.; Kagohara, K.; Kaneda, H.; Suzuki, Y.; Watanabe, M.; Tsumura, S.; Matsuta, N.; Ishiyama, T.; Sugito, N.; Hirouchi, D.; Ishiguro, S.; Yoshida, H.; Tanaka, K.; Takenami, D.; Kashihara, S.; Tanaka, T.; Moriki, H.

    2016-12-01

    A Mj 6.5 earthquake hit Kumamoto prefecture, central Kyushu, southwest Japan at 21:26 JST on April 14th. About 28 hours after, The Mj 7.3 earthquake occurred at 01:25 JST on April 16, and caused severe shaking in and around the epicentral region. An ENE-to-NE-trending surface rupture zone associated with the earthquakes appeared along the previously mapped 100-km-long active fault called the Futagawa-Hinagu fault zone (FHFZ) (Watanabe et al., 1979; Research Group for Active Tectonics in Kyushu, 1989; Research Group for Active Faults of Japan, 1991; Ikeda et al., 2001; Nakata and Imaizumi ed, 2002). According to our field survey for three months, we found the 31-km-length surface rupture close to the traces of the northeastern part of the FHFZ, and another 5-km-length rupture on a part of the Denokuchi fault. The rupture along the FHFZ shows right-lateral strike slip mainly ( 2.1 m in maximum). The rupture on the Denokuchi fault, far from about 2km east of the FHFZ, is the normal component with down to northwest. These coseismic ruptures of the Mj 7.3 earthquake have been represented to be a characteristic movement of the northeastern part of the FHFZ. The deformations such as a series of the open cracks with NW-SE trending were traceable for a distance of 5.4 km from Kengun to Shirakawa River in and around the downtown of Kumamoto city. Those features followed on tectonic landform by the active fault and on the line of the fringe abnormal in InSAR image (Geospatial Information Authority of Japan, 2016) represent small triggered slip. The eyewitness of local resident and our observation revealed that a coseismic small rupture of the Mj 6.5 earthquake had been appeared along the southern end of Mj 7.3 earthquake ruptures. Seismic inversion theory (DPRI, Kyoto Univ, 2016) showed that the coseismic rupture propagated toward NE along the strike of the FHFZ, and an asperity near the surface was recognized from 10 km far from the epicenter toward NE. The area of maximum

  3. Bacteriophages reduce experimental contamination of hard surfaces, tomato, spinach, broccoli, and ground beef by Escherichia coli O157:H7.

    Science.gov (United States)

    Abuladze, Tamar; Li, Manrong; Menetrez, Marc Y; Dean, Timothy; Senecal, Andre; Sulakvelidze, Alexander

    2008-10-01

    A bacteriophage cocktail (designated ECP-100) containing three Myoviridae phages lytic for Escherichia coli O157:H7 was examined for its ability to reduce experimental contamination of hard surfaces (glass coverslips and gypsum boards), tomato, spinach, broccoli, and ground beef by three virulent strains of the bacterium. The hard surfaces and foods contaminated by a mixture of three E. coli O157:H7 strains were treated with ECP-100 (test samples) or sterile phosphate-buffered saline buffer (control samples), and the efficacy of phage treatment was evaluated by comparing the number of viable E. coli organisms recovered from the test and control samples. Treatments (5 min) with the ECP-100 preparation containing three different concentrations of phages (10(10), 10(9), and 10(8) PFU/ml) resulted in statistically significant reductions (P = E. coli O157:H7 organisms recovered from the glass coverslips. Similar treatments resulted in reductions of 100%, 95%, and 85%, respectively, in the number of E. coli O157:H7 organisms recovered from the gypsum board surfaces; the reductions caused by the two most concentrated phage preparations were statistically significant. Treatment with the least concentrated preparation that elicited significantly less contamination of the hard surfaces (i.e., 10(9) PFU/ml) also significantly reduced the number of viable E. coli O157:H7 organisms on the four food samples. The observed reductions ranged from 94% (at 120 +/- 4 h posttreatment of tomato samples) to 100% (at 24 +/- 4 h posttreatment of spinach samples). The data suggest that naturally occurring bacteriophages may be useful for reducing contamination of various hard surfaces, fruits, vegetables, and ground beef by E. coli O157:H7.

  4. Regulation and Functional Significance of Airway Surface Liquid pH

    Directory of Open Access Journals (Sweden)

    Coakley RD

    2001-07-01

    Full Text Available In gastrointestinal tissues, cumulative evidence from both in vivo and in vitro studies suggests a role for the cystic fibrosis transmembrane conductance regulator (CFTR in apical epithelial bicarbonate conductance. Abnormal lumenal acidification is thus hypothesized to play a role in the genesis of cystic fibrosis (CF pancreatic disease. However, consensus regarding CFTR's participation in pH regulation of airway surface liquid (ASL and thus the contribution of ASL pH to the etiology of CF lung disease, is lacking. The absence of data reflects difficulties in both sampling ASL in vivo and modeling ASL biology in vitro. Here we evaluate the evidence in support of a lumenal acidification hypothesis in the CF lung, summarize current knowledge of pH regulation in the normal airway and illustrate how hyper-acidified airway secretions could contribute to the pathogenesis of CF lung disease.

  5. Micro-structuring of polycarbonate-urethane surfaces in order to reduce platelet activation and adhesion.

    Science.gov (United States)

    Clauser, Johanna; Gester, Kathrin; Roggenkamp, Jan; Mager, Ilona; Maas, Judith; Jansen, Sebastian V; Steinseifer, Ulrich

    2014-01-01

    In the development of new hemocompatible biomaterials, surface modification appears to be a suitable method in order to reduce the thrombogenetic potential of such materials. In this study, polycarbonate-urethane (PCU) tubes with different surface microstructures to be used for aortic heart valve models were investigated with regard to the thrombogenicity. The surface structures were produced by using a centrifugal casting process for manufacturing PCU tubes with defined casting mold surfaces which are conferred to the PCU surface during the process. Tubes with different structures defined by altering groove widths were cut into films and investigated under dynamic flow conditions in contact with porcine blood. The analysis was carried out by laser scanning microscopy which allowed for counting various morphological types of platelets with regard to the grade of activation. The comparison between plain and shaped PCU samples showed that the surface topography led to a decline of the activation of the coagulation cascade and thus to the reduction of the fibrin synthesis. Comparing different types of structures revealed that smooth structures with a small groove width (d ~ 3 μm) showed less platelet activation as well as less adhesion in contrast to a distinct wave structure (d ~ 90 μm). These results prove surface modification of polymer biomaterials to be a suitable method for reducing thrombogenicity and hence give reason for further alterations and improvements.

  6. Reducing Ice Adhesion on Nonsmooth Metallic Surfaces: Wettability and Topography Effects.

    Science.gov (United States)

    Ling, Edwin Jee Yang; Uong, Victor; Renault-Crispo, Jean-Sébastien; Kietzig, Anne-Marie; Servio, Phillip

    2016-04-06

    The effects of ice formation and accretion on external surfaces range from being mildly annoying to potentially life-threatening. Ice-shedding materials, which lower the adhesion strength of ice to its surface, have recently received renewed research attention as a means to circumvent the problem of icing. In this work, we investigate how surface wettability and surface topography influence the ice adhesion strength on three different surfaces: (i) superhydrophobic laser-inscribed square pillars on copper, (ii) stainless steel 316 Dutch-weave meshes, and (iii) multiwalled carbon nanotube-covered steel meshes. The finest stainless steel mesh displayed the best performance with a 93% decrease in ice adhesion relative to polished stainless steel, while the superhydrophobic square pillars exhibited an increase in ice adhesion by up to 67% relative to polished copper. Comparisons of dynamic contact angles revealed little correlation between surface wettability and ice adhesion. On the other hand, by considering the ice formation process and the fracture mechanics at the ice-substrate interface, we found that two competing mechanisms governing ice adhesion strength arise on nonplanar surfaces: (i) mechanical interlocking of the ice within the surface features that enhances adhesion, and (ii) formation of microcracks that act as interfacial stress concentrators, which reduce adhesion. Our analysis provides insight toward new approaches for the design of ice-releasing materials through the use of surface topographies that promote interfacial crack propagation.

  7. Mineralogy of smectites in the surface sediments from the East Pacific and its significance

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    XRD, TEM, SEM and EDS are employed to analyze smectites in the clay fraction of the surface sediments from the East Pacific. It is shown from the XRD results that the clay fraction consists of about 20% smectites. Three types of smectites are identified, Fe-rich (TypeⅠ), Fe, Mg-rich (Type Ⅱ) and Na,Ca smectite (Type Ⅲ), and most of them are not well-crystallized. TypeⅠ is widely distributed in sediments, showing honeycomblike in the SEM, and aggregated or dispersive hairlike, or cloudy assemblage with a bit curl near its edge in the TEM. This type is considered to be typomorphic type of authigenic smectite in the East Pacific. TypeⅡ is similar to TypeⅠ in micromorphology in the TEM, showing a transition micronite, while Type Ⅲ is tabletlike in the TEM with an unclear edge. TypeⅠ may be altered from volcanics and some of them even precipitated from the low subthermal water. TypeⅡ could also be form- ed in the ocean floor, while Type Ⅲ comes from dry and distant continental area. This study suggests that the characteristic of chemical composition and morphology of smectite may give a clue to understand sediment source, origin of minerals and sedimentation in the deep sea.

  8. Mineralogy of smectites in the surface sediments from the East Pacific and its significance

    Institute of Scientific and Technical Information of China (English)

    ZHANGHaiping; SHIXuefa; CHENJin; XUEYongfang; HEJinfa; ZHUDesheng; XINChunying; WEIJianwei

    2003-01-01

    XRD, TEM, SEM and EDS are employed to analyze smectites in the clay fraction of the surface sediments from the East Pacific. It is shown from the XRD results that the clay fraction consists of about 20% smectites.Three types of smectites are identified, Fe-rich (Type Ⅰ), Fe,Mg-rich (Type Ⅱ) and Na,Ca smectite (Type Ⅲ), and most of them are not well-crystallized. Type Ⅰ is widely distributed in sediments, showing honeycomblike in the SEM, and aggregated or dispersive hairlike, or cloudy assemblage with a bit curl near its edge in the TEM. This type is considered to be typomorphic type of authigenic smectite in the East Pacific. Type Ⅱ is similar to Type Ⅰ in micromorphology in the TEM, showing a transition micronite, while Type Ⅲ is tabletlike in the TEM with an unclear edge. Type Ⅰ may be altered from voleanics and some of them even precipitated from the low subthermal water. Type Ⅱ could also be formed in the ocean floor, while Type Ⅲ comes from dry and distant continental area. This study suggests that the characteristic of chemical composition and morphology of smectite may give a clue to understand sediment source, origin of minerals and sedimentation in the deep sea.

  9. P-glycoprotein-170 inhibition significantly reduces cortisol and ciclosporin efflux from human intestinal epithelial cells and T lymphocytes.

    Science.gov (United States)

    Farrell, R J; Menconi, M J; Keates, A C; Kelly, C P

    2002-05-01

    To assess the role of P-glycoprotein-170 (P-gp) in transporting cortisol and ciclosporin from human intestinal epithelium and T lymphocytes. The effect of P-gp inhibitors (verapamil, 0-100 microM; PSC 833, 0-20 microM) on the intracellular accumulation of 3H-cortisol and 3H-ciclosporin was studied in confluent layers of human Caco-2 cells (n=6), a P-gp-dependent absorptive intestinal epithelial cell phenotype, and moderately resistant MDRhigh CEM/VBL 100 T cells (n=6). The transport of 3H-vinblastine, a strong multidrug resistance (MDR) substrate, and 3H-progesterone, a poor MDR substrate, was also studied. Caco-2 cells had a 2.4-, 6.6-, 6.7- and 1.03-fold higher net basal to apical transport (efflux) of 3H-cortisol, 3H-ciclosporin, 3H-vinblastine and 3H-progesterone, respectively. PSC 833 (20 microM) reduced cortisol efflux by 69% (0.23 +/- 0.04 to 0.07 +/- 0.01 pmol/cm2/h, P 0.1 microM) and verapamil (> 1 microM) restored the intracellular level of 3H-cortisol and 3H-ciclosporin in MDRhigh CEM/VBL 100 T cells to that of MDRlow CEM cells with little change in accumulation in the MDRlow parental cell line. P-gp inhibitors significantly increase intracellular cortisol and ciclosporin levels in human intestinal epithelium and T lymphocytes in a dose-dependent manner, demonstrating a potential mechanism for overcoming poor response to immunosuppressant therapy in refractory inflammatory bowel disease.

  10. Airfoil-shaped micro-mixers for reducing fouling on membrane surfaces

    Science.gov (United States)

    Ho, Clifford K; Altman, Susan J; Clem, Paul G; Hibbs, Michael; Cook, Adam W

    2012-10-23

    An array of airfoil-shaped micro-mixers that enhances fluid mixing within permeable membrane channels, such as used in reverse-osmosis filtration units, while minimizing additional pressure drop. The enhanced mixing reduces fouling of the membrane surfaces. The airfoil-shaped micro-mixer can also be coated with or comprised of biofouling-resistant (biocidal/germicidal) ingredients.

  11. Reduced bacterial growth and increased osteoblast proliferation on titanium with a nanophase TiO2 surface treatment

    Directory of Open Access Journals (Sweden)

    Bhardwaj G

    2017-01-01

    Full Text Available Garima Bhardwaj, Thomas J Webster Department of Chemical Engineering, Northeastern University, Boston, MA, USA Background: The attachment and initial growth of bacteria on an implant surface dictates the progression of infection. Treatment often requires aggressive antibiotic use, which does not always work. To overcome the difficulties faced in systemic and local antibiotic delivery, scientists have forayed into using alternative techniques, which includes implant surface modifications that prevent initial bacterial adhesion, foreign body formation, and may offer a controlled inflammatory response.Objective: The current study focused on using electrophoretic deposition to treat titanium with a nanophase titanium dioxide surface texture to reduce bacterial adhesion and growth. Two distinct nanotopographies were analyzed, Ti-160, an antimicrobial surface designed to greatly reduce bacterial colonization, and Ti-120, an antimicrobial surface with a topography that upregulates osteoblast activity while reducing bacterial colonization; the number following Ti in the nomenclature represents the atomic force microscopy root-mean-square roughness value in nanometers.Results: There was a 95.6% reduction in Staphylococcus aureus (gram-positive bacteria for the Ti-160-treated surfaces compared to the untreated titanium alloy controls. There was a 90.2% reduction in Pseudomonas aeruginosa (gram-negative bacteria on Ti-160-treated surfaces compared to controls. For ampicillin-resistant Escherichia coli, there was an 81.1% reduction on the Ti-160-treated surfaces compared to controls. Similarly for surfaces treated with Ti-120, there was an 86.8% reduction in S. aureus, an 82.1% reduction in P. aeruginosa, and a 48.6% reduction in ampicillin-resistant E. coli. The Ti-120 also displayed a 120.7% increase at day 3 and a 168.7% increase at day 5 of osteoblast proliferation over standard titanium alloy control surfaces.Conclusion: Compared to untreated surfaces

  12. Reducing Escherichia coli growth on a composite biomaterial by a surface immobilized antimicrobial peptide

    Energy Technology Data Exchange (ETDEWEB)

    Buckholtz, Gavin A.; Reger, Nina A. [Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282 (United States); Anderton, William D.; Schimoler, Patrick J. [Orthopaedic Biomechanics Research Laboratory, Allegheny General Hospital, Pittsburgh, PA 15212 (United States); Roudebush, Shana L.; Meng, Wilson S. [Division of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282 (United States); Miller, Mark C. [Orthopaedic Biomechanics Research Laboratory, Allegheny General Hospital, Pittsburgh, PA 15212 (United States); Gawalt, Ellen S., E-mail: gawalte@duq.edu [Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, PA 15282 (United States); McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15219 (United States)

    2016-08-01

    A new composite bioceramic consisting of calcium aluminum oxide (CaAlO) and hydroxyapatite (HA) was functionalized with the synthetic antimicrobial peptide Inverso-CysHHC10. CaAlO is a bioceramic that can be mold cast easily and quickly at room temperature. Improved functionality was previously achieved through surface reactions. Here, composites containing 0–5% HA (by mass) were prepared and the elastic modulus and modulus of rupture were mechanically similar to non-load bearing bone. The addition of hydroxyapatite resulted in increased osteoblast attachment (> 180%) and proliferation (> 140%) on all composites compared to 100% CaAlO. Antimicrobial peptide (AMP) immobilization was achieved using an interfacial alkene-thiol click reaction. The linked AMP persisted on the composite (> 99.6% after 24 h) and retained its activity against Escherichia coli based on N-phenylnaphthylamine uptake and bacterial turbidity tests. Overall, this simple scaffold system improves osteoblast activity and reduces bacterial activity. - Highlights: • Calcium aluminum oxide and hydroxyapatite were cast into a composite material. • Osteoblast attachment and proliferation were significantly increased on composites. • An active antimicrobial peptide was linked to and remained stable on the composite. • Bacterial turbidity and NPN uptake tests showed modified composites had an effect equal to a 10 μM Inverso-CysHHC10 solution. • Antimicrobial peptide linkage did not affect the increased osteoblast performance.

  13. The role of wastewater treatment in reducing pollution of surface waters with zearalenone.

    Science.gov (United States)

    Gromadzka, Karolina; Waśkiewicz, Agnieszka; Świetlik, Joanna; Bocianowski, Jan; Goliński, Piotr

    2015-06-01

    Zearalenone (ZEA) is a mycotoxin produced by some Fusarium species in food and feed. The toxicity of ZEA and its metabolites is related to the chemical structure of the mycotoxin, which is similar to naturally occurring oestrogens. Currently, there is increasing awareness of the presence of fungi and their toxic metabolites in the aquatic environment. One of the sources of these compounds are the effluents from wastewater treatment plants. The average annual efficiency of zearalenone reduction in the Łęczyca plant in our three-year study was in the range from 51.35 to 69.70 %. The threeway analysis of variance (year, month, and kind of wastewater) shows that the main effects of all factors and all interactions between them were significant for zearalenone and dissolved organic carbon content. Our findings suggest that wastewater is not the main source of surface water pollution with zearalenone. Future research should investigate the means to reduce ZEA and its migration from the fields through prevention strategies such as breeding for crops, plant debris management (crop rotation, tillage), and/or chemical and biological control.

  14. Roughness distribution of multiple hit and long surface diffusion length noise reduced discrete growth models

    Science.gov (United States)

    Disrattakit, P.; Chanphana, R.; Chatraphorn, P.

    2016-11-01

    Conventionally, the universality class of a discrete growth model is identified via the scaling of interface width. This method requires large-scale simulations to minimize finite-size effects on the results. The multiple hit noise reduction techniques (m > 1 NRT) and the long surface diffusion length noise reduction techniques (ℓ > 1 NRT) have been used to promote the asymptotic behaviors of the growth models. Lately, an alternative method involving comparison of roughness distribution in the steady state has been proposed. In this work, the roughness distribution of the (2 +1)-dimensional Das Sarma-Tamborenea (DT), Wolf-Villain (WV), and Larger Curvature (LC) models, with and without NRTs, are calculated in order to investigate effects of the NRTs on the roughness distribution. Additionally, effective growth exponents of the noise reduced (2 +1)-dimensional DT, WV and LC models are also calculated. Our results indicate that the NRTs affect the interface width both in the growth and the saturation regimes. In the steady state, the NRTs do not seem to have any impact on the roughness distribution of the DT model, but it significantly changes the roughness distribution of the WV and LC models to the normal distribution curves.

  15. Overexpression of rice glutaredoxins (OsGrxs) significantly reduces arsenite accumulation by maintaining glutathione pool and modulating aquaporins in yeast.

    Science.gov (United States)

    Verma, Pankaj Kumar; Verma, Shikha; Meher, Alok Kumar; Pande, Veena; Mallick, Shekhar; Bansiwal, Amit Kumar; Tripathi, Rudra Deo; Dhankher, Om Parkash; Chakrabarty, Debasis

    2016-09-01

    Arsenic (As) is an acute poison and class I carcinogen, can cause a serious health risk. Staple crops like rice are the primary source of As contamination in human food. Rice grown on As contaminated areas accumulates higher As in their edible parts. Based on our previous transcriptome data, two rice glutaredoxins (OsGrx_C7 and OsGrx_C2.1) were identified that showed up-regulated expression during As stress. Here, we report OsGrx_C7 and OsGrx_C2.1 from rice involved in the regulation of intracellular arsenite (AsIII). To elucidate the mechanism of OsGrx mediated As tolerance, both OsGrxs were cloned and expressed in Escherichia coli (Δars) and Saccharomyces cerevisiae mutant strains (Δycf1, Δacr3). The expression of OsGrxs increased As tolerance in E. coli (Δars) mutant strain (up to 4 mM AsV and up to 0.6 mM AsIII). During AsIII exposure, S. cerevisiae (Δacr3) harboring OsGrx_C7 and OsGrx_C2.1 have lower intracellular AsIII accumulation (up to 30.43% and 24.90%, respectively), compared to vector control. Arsenic accumulation in As-sensitive S. cerevisiae mutant (Δycf1) also reduced significantly on exposure to inorganic As. The expression of OsGrxs in yeast maintained intracellular GSH pool and increased extracellular GSH concentration. Purified OsGrxs displays in vitro GSH-disulfide oxidoreductase, glutathione reductase and arsenate reductase activities. Also, both OsGrxs are involved in AsIII extrusion by altering the Fps1 transcripts in yeast and protect the cell by maintaining cellular GSH pool. Thus, our results strongly suggest that OsGrxs play a crucial role in the maintenance of the intracellular GSH pool and redox status of the cell during both AsV and AsIII stress and might be involved in regulating intracellular AsIII levels by modulation of aquaporin expression and functions.

  16. Reduced plasma membrane surface expression of GLAST mediates decreased glutamate regulation in the aged striatum.

    Science.gov (United States)

    Nickell, Justin; Salvatore, Michael F; Pomerleau, Francois; Apparsundaram, Subbu; Gerhardt, Greg A

    2007-11-01

    Extracellular L-glutamate poses a severe excitotoxic threat to neurons and glia when unregulated, therefore low synaptic levels of this neurotransmitter must be maintained via a rapid and robust transport system. A recent study from our laboratory showed a reduced glutamate uptake rate in the striatum of the aged Fischer 344 (F344) rat, yet the mechanism underlying this phenomenon is unknown. The current study utilized in vivo electrochemical recordings, immunoblotting and biotinylation in young (6 months), late-middle aged (18 months) and aged (24 months) F344 rats to elucidate the potential role that glutamate transporters (GLT-1, GLAST, and EAAC1) may play in this mechanism. Here we show that the time necessary to clear glutamate from the late-middle aged and aged striatum is significantly prolonged in comparison to the young striatum. In addition, an analysis of various sub-regions of the striatum revealed a marked dorsoventral gradient in terms of glutamate clearance times in the aged striatum, a phenomenon which was not present in the striatum of the animals of the remaining age groups. We also found that the decreased glutamate clearance time observed in the late-middle aged and aged rats is not due to a decrease in the production of total transporter protein among these three transporters. Rather, a significant reduction in the amount of GLAST expressed on the plasma membrane surface in the aged animals (approximately 55% when compared to young rats) may contribute to this phenomenon. These age-related alterations in extracellular l-glutamate regulation may be key contributors to the increased susceptibility of the aged brain to excitotoxic insults such as stroke and hypoxia.

  17. How to reduce resistance to movement of alkane liquid drops across tilted surfaces without relying on surface roughening and perfluorination.

    Science.gov (United States)

    Urata, Chihiro; Masheder, Benjamin; Cheng, Dalton F; Hozumi, Atsushi

    2012-12-21

    Alkylsilane-derived monolayer-covered surfaces generally display a reasonably good level of hydrophobicity but poor oleophobicity. Here, we demonstrate that the physical attributes of alkylsilane-derived surfaces (liquid-like or solid-like) are dependent on the alkyl chain length and density, and these factors subsequently have significant influence upon the dynamic dewetting behavior toward alkanes (C(n)H(2n+2), where n = 7-16). In this study, we prepared and characterized hybrid films through a simple sol-gel process based on the cohydrolysis and co-condensation of a mixture of a range of alkyltriethoxysilanes (C(n)H(2n+1)Si(OEt)(3), where n = 3, 6, 8, 10, 12, 14, 16, and 18) and tetramethoxysilane (TMOS). Surprisingly, when the carbon number (C(n)) of alkyl chain was 10 and below, the produced hybrid films were all smooth, highly transparent, and showed negligible contact angle (CA) hysteresis. On these hybrid surfaces, 5 μL drops of alkanes (n-hexadecane, n-dodecane, and n-decane) could move easily at low tilt angles (oleophobicity. Therefore, the critical C(n) of alkyl chain used for determining final dynamic dewetting behavior against alkane liquids was 12. Furthermore, our hybrid surfaces exhibited excellent antifingerprint properties, particularly demonstrating low adhesion and easy removal from the surface.

  18. Enhanced photothermal effect of surface oxidized silicon nanocrystals anchored to reduced graphene oxide nanosheets

    Science.gov (United States)

    Afshani, Parichehr; Moussa, Sherif; Atkinson, Garrett; Kisurin, Vitaly Y.; Samy El-Shall, M.

    2016-04-01

    We demonstrate the coupling of the photothermal effects of silicon nanocrystals and graphene oxide (GO) dispersed in water. Using laser irradiation (532 nm or 355 nm) of suspended Si nanocrystals in an aqueous solution of GO, the synthesis of surface oxidized Si-reduced GO nanocomposites (SiOx/Si-RGO) is reported. The laser reduction of GO is accompanied by surface oxidation of the Si nanocrystals resulting in the formation of the SiOx/Si-RGO nanocomposites. The SiOx/Si-RGO nanocomposites are proposed as promising materials for photothermal therapy and for the efficient conversion of solar energy into usable heat for a variety of thermal and thermomechanical applications.

  19. Reduced ability to detect surface-related biofilm bacteria after antibiotic exposure under in vitro conditions

    DEFF Research Database (Denmark)

    Ravn, Christen; Furustrand Tafin, Ulrika; Bétrisey, Bertrand

    2016-01-01

    -dependent drugs (i.e. daptomycin and ciprofloxacin) had a strong suppressive effect on bacterial growth and reduced the ability to detect planktonic and biofilm bacteria. Exposure to rifampin rapidly caused emergence of resistance. Our findings indicate that preoperative administration of antibiotics may have......Background and purpose - Antibiotic treatment of patients before specimen collection reduces the ability to detect organisms by culture. We investigated the suppressive effect of antibiotics on the growth of non-adherent, planktonic, and surface-related biofilm bacteria in vitro by using sonication...... heterogeneous effects on the ability to detect biofilm bacteria....

  20. Development of electrically conductive-superoleophobic micropillars for reducing surface adhesion of oil at low temperatures

    Science.gov (United States)

    Pan, Zihe; Wang, Tianchang; Zhou, Yikang; Zhao, Boxin

    2016-12-01

    Electrically conductive and superoleophobic micropillars have been developed through the construction of biomimetic micropillars using Ag-filled epoxy composites and the incorporation of FDTS on the micropillar surface. These micropillars are found to be superoleophobic with an oil contact angle of 140°, demonstrating excellent self-cleaning properties. The conductivity of micropillars allows for the Joule-heating effect to actively reduce the adhesion and even unfreeze the frozen oil droplets by passing electrical current. Electrical resistance of the composite micropillars was modulated by two orders of magnitudes by varying the contents of Ag flakes from 45 wt% to 65 wt%. The effectiveness of conductive micropillars for surface un-freezing was investigated by applying DC current to decrease the adhesion strength of frozen oil droplets on surfaces. The results showed a pronounced reduction of frozen oil adhesion force by 60% when the resistance increased from 7.5 Ω to 877 Ω after applying DC current for 2 min. By continuously applying DC current for 3 min, the frozen oil adhesion decreased to 0.05 N, reaching zero when the surface was heated up to -10 °C after applying DC current for 5 min. In contrast, when the droplet was heated up to -5 °C by hot air, there is still a substantial force of adhesion. The research findings demonstrate the use of constructing conductive-superoleophobic composite micropillars at surface for eliminating the frozen oil from surfaces at low temperatures.

  1. Physical origins of ruled surfaces on the reduced density matrices geometry

    Science.gov (United States)

    Chen, Ji-Yao; Ji, Zhengfeng; Liu, Zheng-Xin; Qi, Xiaofei; Yu, Nengkun; Zeng, Bei; Zhou, Duanlu

    2017-02-01

    The reduced density matrices (RDMs) of many-body quantum states form a convex set. The boundary of low dimensional projections of this convex set may exhibit nontrivial geometry such as ruled surfaces. In this paper, we study the physical origins of these ruled surfaces for bosonic systems. The emergence of ruled surfaces was recently proposed as signatures of symmetry-breaking phase. We show that, apart from being signatures of symmetry-breaking, ruled surfaces can also be the consequence of gapless quantum systems by demonstrating an explicit example in terms of a two-mode Ising model. Our analysis was largely simplified by the quantum de Finetti's theorem—in the limit of large system size, these RDMs are the convex set of all the symmetric separable states. To distinguish ruled surfaces originated from gapless systems from those caused by symmetry-breaking, we propose to use the finite size scaling method for the corresponding geometry. This method is then applied to the two-mode XY model, successfully identifying a ruled surface as the consequence of gapless systems.

  2. Plasma graft of poly(ethylene glycol) methyl ether methacrylate (PEGMA) on RGP lens surface for reducing protein adsorption

    Science.gov (United States)

    Shiheng, Yin; Li, Ren; Yingjun, Wang

    2017-01-01

    Poly(ethylene glycol) methyl ether methacrylate (PEGMA) was grafted on fluorosilicone acrylate rigid gas permissible contact lens surface by means of argon plasma induced polymerization to improve surface hydrophilicity and reduce protein adsorption. The surface properties were characterized by contact angle measurement, x-ray photoelectron spectroscopy (XPS) and atomic force microscopy respectively. The surface protein adsorption was evaluated by lysozyme solution immersion and XPS analysis. The results indicated that a thin layer of PEGMA was successfully grafted. The surface hydrophilicity was bettered and surface free energy increased. The lysozyme adsorption on the lens surface was reduced greatly. The study was supported by National Natural Science Foundation of China (No. 51273072).

  3. Surface modifications of photoanodes in dye sensitized solar cells: enhanced light harvesting and reduced recombination

    Science.gov (United States)

    Saxena, Vibha; Aswal, D. K.

    2015-06-01

    In a quest to harvest solar power, dye-sensitized solar cells (DSSCs) have potential for low-cost eco-friendly photovoltaic devices. The major processes which govern the efficiency of a DSSC are photoelectron generation, injection of photo-generated electrons to the conduction band (CB) of the mesoporous nanocrystalline semiconductor (nc-SC); transport of CB electrons through nc-SC and subsequent collection of CB electrons at the counter electrode (CE) through the external circuit; and dye regeneration by redox couple or hole transport layer (HTL). Most of these processes occur at various interfaces of the photoanode. In addition, recombination losses of photo-generated electrons with either dye or redox molecules take place at the interfaces. Therefore, one of the key requirements for high efficiency is to improve light harvesting of the photoanode and to reduce the recombination losses at various interfaces. In this direction, surface modification of the photoanode is the simplest method among the various other approaches available in the literature. In this review, we present a comprehensive discussion on surface modification of the photoanode, which has been adopted in the literature for not only enhancing light harvesting but also reducing recombination. Various approaches towards surface modification of the photoanode discussed are (i) fluorine-doped tin oxide (FTO)/nc-SC interface modified via a compact layer of semiconductor material which blocks exposed sites of FTO to electrolyte (or HTL), (ii) nc-SC/dye interface modification either through acid treatment resulting in enhanced dye loading due to a positively charged surface or by depositing insulating/semiconducting blocking layer on the nc-SC surface, which acts as a tunneling barrier for recombination, (iii) nc-SC/dye interface modified by employing co-adsorbents which helps in reducing the dye aggregation and thereby recombination, and (iv) dye/electrolyte (or dye/HTL) interface modification using

  4. Reduced Heat Flux Through Preferential Surface Reactions Leading to Vibrationally and Electronically Excited Product States

    Science.gov (United States)

    2016-03-04

    AFRL-AFOSR-VA-TR-2016-0124 Reduced Heat Flux Through Preferential Surface Reactions Leading to Vibrationally and Electronically Excited Product...Reactions Leading to Vibrationally and Electronically Excited Product States 5a. CONTRACT NUMBER FA9550-12-1-0486 5b. GRANT NUMBER 5c. PROGRAM... Leading to Vibrationally and Electronically Excited Product States FINAL TECHNICAL REPORT: Grant #FA9550-12-1-0486 2013 Basic Research Initiative (BRI

  5. Significance of sample thickness and surface segregation on the electrical conductivity of Wesgo AL995 alumina under ITER environments

    Energy Technology Data Exchange (ETDEWEB)

    Howlader, M.M.R.; Kinoshita, Chiken E-mail: c.k.tne@mbox.nc.kyushu-u.ac.jp; Shiiyama, K.; Kutsuwada, M.; Higuchi, T

    2000-12-01

    The electrical conductivity of 158, 295 and 610 {mu}m thick Wesgo AL995 alumina was measured under 1 MeV electron irradiation with an electric field of 300 kV/m at temperatures up to 723 K. A significant increase in the conductivity with increasing the sample thickness is confirmed, but no substantial bulk degradation is found under irradiation up to a dose of 7.0x10{sup 22} e/m{sup 2} (7.97x10{sup -5} dpa) at 723 K. However, surface breakdown is found only in 295 and 610 {mu}m thick specimens. The non-existence of the surface breakdown in 158 {mu}m thick specimen is thought to be due to the sinks effect of point defects at the surface. The X-ray analysis of the virgin and degraded specimens through scanning electron microscopy (SEM) reveals the segregation of impurities along the grain boundaries on the degraded surface. The segregation of impurities assists leaking of surface current along the grain boundaries.

  6. Reducing the Discrepancy Between ASTER and MODIS Land Surface Temperature Products

    Directory of Open Access Journals (Sweden)

    Changqing Ke

    2007-12-01

    Full Text Available Human-induced global warming has significantly increased the importance ofsatellite monitoring of land surface temperature (LST on a global scale. The MODerate-resolution Imaging Spectroradiometer (MODIS provides a 1-km resolution LST productwith almost daily coverage of the Earth, invaluable to both local and global change studies.The Advanced Spaceborne Thermal Emission Reflection Radiometer (ASTER provides aLST product with a high spatial resolution of 90-m and a 16-day recurrent cycle,simultaneously acquired at the same height and nadir view as MODIS. ASTER andMODIS are complementary in resolution, offering a unique opportunity for scale-relatedstudies. ASTER and MODIS LST have been widely used but the errors in LST were mostlydisregarded. Correction of ASTER-to-MODIS LST discrepancies is essential for studiesreliant upon the joint use of these sensors. In this study, we compared three correctionapproaches: the Wan et al.’s approach, the refined Wan et al.’s approach, and thegeneralized split window (GSW algorithm based approach. The Wan et al.’s approachcorrects the MODIS 1-km LST using MODIS 5-km LST. The refined approach modifiesthe Wan et al.’s approach through incorporating ASTER emissivity and MODIS 5-km data.The GSW algorithm approach does not use MODIS 5-km but only ASTER emissivity data. We examined the case over a semi-arid terrain area for the part of the Loess Plateau of China. All the approaches reduced the ASTER-to-MODIS LST discrepancy effectively. With terrain correction, the original ASTER-to-MODIS LST difference reduced from 2.7±1.28 K to -0.1±1.87 K for the Wan et al.’s approach, 0.2±1.57 K for the refined approach, and 0.1±1.33 K for the GSW algorithm based approach. Among all the approaches, the GSW algorithm based approach performed best in terms of mean, standard deviation, root mean square root, and correlation coefficient.

  7. Surface deformation associated with the 2013 Mw7.7 Balochistan earthquake: Geologic slip rates may significantly underestimate strain release

    Science.gov (United States)

    Gold, Ryan; Reitman, Nadine; Briggs, Richard; Barnhart, William; Hayes, Gavin

    2015-04-01

    The 24 September 2013 Mw7.7 Balochistan, Pakistan earthquake ruptured a ~200 km-long stretch of the 60° ± 15° northwest-dipping Hoshab fault in southern Pakistan. The earthquake is notable because it produced the second-largest lateral surface displacement observed for a continental strike-slip earthquake. Surface displacements and geodetic and teleseismic inversions indicate that peak slip occurred within the upper 0-3 km of the crust. To explore along-strike and fault-perpendicular surface deformation patterns, we remotely mapped the surface trace of the rupture and measured its surface deformation using high-resolution (0.5 m) pre- and post-event satellite imagery. Post-event images were collected 7-114 days following the earthquake, so our analysis captures the sum of both the coseismic and post-seismic (e.g., after slip) deformation. We document peak left-lateral offset of ~15 m using 289 near-field (±10 m from fault) laterally offset piercing points, such as streams, terrace risers, and roads. We characterize off-fault deformation by measuring the medium- (±200 m from fault) and far-field (±10 km from fault) displacement using manual (242 measurements) and automated image cross-correlation methods. Off-fault peak lateral displacement values (medium- and far-field) are ~16 m and commonly exceed the on-fault displacement magnitudes. Our observations suggest that coseismic surface displacement typically increases with distance away from the surface trace of the fault; however, the majority of surface displacement is within 100 m of the primary fault trace and is most localized on sections of the rupture exhibiting narrow (<5 m) zones of observable surface deformation. Furthermore, the near-field displacement measurements account for, on average, only 73% of the total coseismic displacement field and the pattern is highly heterogeneous. This analysis highlights the importance of identifying paleoseismic field study sites (e.g. trenches) that span fault

  8. Reduced adhesion of macrophages on anodized titanium with select nanotube surface features.

    Science.gov (United States)

    Rajyalakshmi, Amancherla; Ercan, Batur; Balasubramanian, K; Webster, Thomas J

    2011-01-01

    One of the important prerequisites for a successful orthopedic implant apart from being osteoconductive is the elicitation of a favorable immune response that does not lead to the rejection of the implant by the host tissue. Anodization is one of the simplest surface modification processes used to create nanotextured and nanotubular features on metal oxides which has been shown to improve bone formation. Anodization of titanium (Ti) leads to the formation of TiO(2) nanotubes on the surface, and the presence of these nanotubes mimics the natural nanoscale features of bone, which in turn contributes to improved bone cell attachment, migration, and proliferation. However, inflammatory cell responses on anodized Ti remains to be tested. It is hypothesized that surface roughness and surface feature size on anodized Ti can be carefully manipulated to control immune cell (specifically, macrophages) responses. Here, when Ti samples were anodized at 10 V in the presence of 1% hydrofluoric acid (HF) for 1 minute, nanotextured (nonnanotube) surfaces were created. When anodization of Ti samples was carried out with 1% HF for 10 minutes at 15 V, nanotubes with 40-50 nm diameters were formed, whereas at 20 V with 1% HF for 10 minutes, nanotubes with 60-70 nm diameters were formed. In this study, a reduced density of macrophages was observed after 24 hours of culture on nanotextured and nanotubular Ti samples which were anodized at 10, 15, and 20 V, compared with conventional unmodified Ti samples. This in vitro study thus demonstrated a reduced density of macrophages on anodized Ti, thereby providing further evidence of the greater efficacy of anodized Ti for orthopedic applications.

  9. Reduced adhesion of macrophages on anodized titanium with select nanotube surface features

    Directory of Open Access Journals (Sweden)

    Balasubramanian K

    2011-08-01

    Full Text Available Amancherla Rajyalakshmi1, Batur Ercan2,3, K Balasubramanian1, Thomas J Webster2,31Non-Ferrous Materials Technology Development Centre, Hyderabad, India; 2School of Engineering, 3Department of Orthopedics, Brown University, Providence, RI, USAAbstract: One of the important prerequisites for a successful orthopedic implant apart from being osteoconductive is the elicitation of a favorable immune response that does not lead to the rejection of the implant by the host tissue. Anodization is one of the simplest surface modification processes used to create nanotextured and nanotubular features on metal oxides which has been shown to improve bone formation. Anodization of titanium (Ti leads to the formation of TiO2 nanotubes on the surface, and the presence of these nanotubes mimics the natural nanoscale features of bone, which in turn contributes to improved bone cell attachment, migration, and proliferation. However, inflammatory cell responses on anodized Ti remains to be tested. It is hypothesized that surface roughness and surface feature size on anodized Ti can be carefully manipulated to control immune cell (specifically, macrophages responses. Here, when Ti samples were anodized at 10 V in the presence of 1% hydrofluoric acid (HF for 1 minute, nanotextured (nonnanotube surfaces were created. When anodization of Ti samples was carried out with 1% HF for 10 minutes at 15 V, nanotubes with 40–50 nm diameters were formed, whereas at 20 V with 1% HF for 10 minutes, nanotubes with 60–70 nm diameters were formed. In this study, a reduced density of macrophages was observed after 24 hours of culture on nanotextured and nanotubular Ti samples which were anodized at 10, 15, and 20 V, compared with conventional unmodified Ti samples. This in vitro study thus demonstrated a reduced density of macrophages on anodized Ti, thereby providing further evidence of the greater efficacy of anodized Ti for orthopedic applications.Keywords: anodization, titanium

  10. Implementation and Operational Research: Expedited Results Delivery Systems Using GPRS Technology Significantly Reduce Early Infant Diagnosis Test Turnaround Times.

    Science.gov (United States)

    Deo, Sarang; Crea, Lindy; Quevedo, Jorge; Lehe, Jonathan; Vojnov, Lara; Peter, Trevor; Jani, Ilesh

    2015-09-01

    The objective of this study was to quantify the impact of a new technology to communicate the results of an infant HIV diagnostic test on test turnaround time and to quantify the association between late delivery of test results and patient loss to follow-up. We used data collected during a pilot implementation of Global Package Radio Service (GPRS) printers for communicating results in the early infant diagnosis program in Mozambique from 2008 through 2010. Our dataset comprised 1757 patient records, of which 767 were from before implementation and 990 from after implementation of expedited results delivery system. We used multivariate logistic regression model to determine the association between late result delivery (more than 30 days between sample collection and result delivery to the health facility) and the probability of result collection by the infant's caregiver. We used a sample selection model to determine the association between late result delivery to the facility and further delay in collection of results by the caregiver. The mean test turnaround time reduced from 68.13 to 41.05 days post-expedited results delivery system. Caregivers collected only 665 (37.8%) of the 1757 results. After controlling for confounders, the late delivery of results was associated with a reduction of approximately 18% (0.44 vs. 0.36; P < 0.01) in the probability of results collected by the caregivers (odds ratio = 0.67, P < 0.05). Late delivery of results was also associated with a further average increase in 20.91 days of delay in collection of results (P < 0.01). Early infant diagnosis program managers should further evaluate the cost-effectiveness of operational interventions (eg, GPRS printers) that reduce delays.

  11. Ability of TiO2(110) Surface to Be Fully Hydroxylated and Fully Reduced

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhitao; Garcia, Juan C.; Deskins, N. A.; Lyubinetsky, Igor

    2015-08-06

    Many TiO2 applications (e.g., in heterogeneous catalysis) involve contact with ambient atmosphere and/or water. The resulting hydroxylation can significantly alter its surface properties. While behavior of single, isolated OH species on the model metal oxide surface of rutile TiO2(110) is relatively well understood, much less is known regarding highly-hydroxylated surfaces and/or whether TiO2(110) could be fully-hydroxylated under ultra-high vacuum conditions. Here we report in situ formation of a well-ordered, fully-hydroxylated TiO2(110)-(1 x 1) surface using an enhanced photochemical approach, key parts of which are pre-dosing of water and multi-step dissociative adsorption and subsequent photolysis of the carboxylic (trimethyl acetic) acid. Combining scanning tunneling microscopy, ultra-violet photoelectron spectroscopy and density functional theory results, we show that the attained “super OH” surface is also fully-reduced, as a result of the photochemical trapping of electrons at the OH groups.

  12. In a randomized placebo-controlled add-on study orlistat significantly reduced clozapine-induced constipation.

    Science.gov (United States)

    Chukhin, Evgeny; Takala, Pirjo; Hakko, Helinä; Raidma, Mirjam; Putkonen, Hanna; Räsänen, Pirkko; Terevnikov, Viacheslav; Stenberg, Jan-Henry; Eronen, Markku; Joffe, Grigori

    2013-03-01

    Constipation is a common and potentially fatal side effect of clozapine treatment. Another important side effect of clozapine may also be significant weight gain. Orlistat is a weight-control medication that is known to induce loose stools as a common side effect. This study aimed to explore whether orlistat used to control clozapine-induced weight gain can simultaneously tackle clozapine-related constipation. In this 16-week randomized-controlled study, clozapine-treated patients received add-on orlistat (n=30) or add-on placebo (n=24). Colonic function was measured using the Bristol Stool Form Scale. There was a significant (P=0.039) difference in the prevalence of constipation in favor of orlistat over placebo in completers (n=40) at the endpoint. A decrease in the prevalence of constipation within the orlistat group (P=0.035) was observed (vs. no statistically significant changes in the placebo group). In clozapine-treated patients, orlistat may be beneficial not only for weight control but also as a laxative. As no established treatments for clozapine-induced constipation exist, orlistat can be considered for this population, although more studies are required.

  13. Significant Enhancement of the Adhesion between Metal Films and Polymer Substrates by UV-Ozone Surface Modification in Nanoscale.

    Science.gov (United States)

    Liu, Junshan; He, Licheng; Wang, Liang; Man, Yuncheng; Huang, Luyi; Xu, Zheng; Ge, Dan; Li, Jingmin; Liu, Chong; Wang, Liding

    2016-11-09

    Polymer metallization is extensively used in a variety of micro- and nanosystem technologies. However, the deposited metal film exhibits poor adhesion to polymer substrates, which may cause difficulties in many applications. In this work, ultraviolet (UV)-ozone surface modification is for the first time put forward to enhance the adhesion between metal films and polymer substrates. The adhesion of sputtered Cu films on UV-ozone modified poly(methyl methacrylate) (PMMA) substrates is enhanced by a factor of 6, and that of Au films is improved by a factor of 10. Moreover, metal films on the modified PMMA substrates can withstand a long-time liquid immersion. To understand the mechanism for the adhesion enhancement, the surface modification is studied with contact angle measurements, attenuated total reflection Fourier-transform infrared spectrometry (ATR-FTIR) and atomic force microscopy (AFM). Detailed characterization results indicate that the significant adhesion enhancement is attributed to the increases of both the surface wettability by generating some polar functional groups and the roughness of the surface in nanoscale. To demonstrate this novel polymer metallization method, a 6-in. PMMA chip with arrays of three-electrode electrochemical microsensors is designed and fabricated, and the microsensor exhibits excellent reproducibility, uniformity, and long-term stability.

  14. Mefenamic acid in combination with ribavirin shows significant effects in reducing chikungunya virus infection in vitro and in vivo.

    Science.gov (United States)

    Rothan, Hussin A; Bahrani, Hirbod; Abdulrahman, Ammar Y; Mohamed, Zulqarnain; Teoh, Teow Chong; Othman, Shatrah; Rashid, Nurshamimi Nor; Rahman, Noorsaadah A; Yusof, Rohana

    2016-03-01

    Chikungunya virus (CHIKV) infection is a persistent problem worldwide due to efficient adaptation of the viral vectors, Aedes aegypti and Aedes albopictus mosquitoes. Therefore, the absence of effective anti-CHIKV drugs to combat chikungunya outbreaks often leads to a significant impact on public health care. In this study, we investigated the antiviral activity of drugs that are used to alleviate infection symptoms, namely, the non-steroidal anti-inflammatory drugs (NSAIDs), on the premise that active compounds with potential antiviral and anti-inflammatory activities could be directly subjected for human use to treat CHIKV infections. Amongst the various NSAID compounds, Mefenamic acid (MEFE) and Meclofenamic acid (MECLO) showed considerable antiviral activity against viral replication individually or in combination with the common antiviral drug, Ribavirin (RIBA). The 50% effective concentration (EC50) was estimated to be 13 μM for MEFE, 18 μM for MECLO and 10 μM for RIBA, while MEFE + RIBA (1:1) exhibited an EC50 of 3 μM, and MECLO + RIBA (1:1) was 5 μM. Because MEFE is commercially available and its synthesis is easier compared with MECLO, MEFE was selected for further in vivo antiviral activity analysis. Treatment with MEFE + RIBA resulted in a significant reduction of hypertrophic effects by CHIKV on the mouse liver and spleen. Viral titre quantification in the blood of CHIKV-infected mice through the plaque formation assay revealed that treatment with MEFE + RIBA exhibited a 6.5-fold reduction compared with untreated controls. In conclusion, our study demonstrated that MEFE in combination with RIBA exhibited significant anti-CHIKV activity by impairing viral replication in vitro and in vivo. Indeed, this finding may lead to an even broader application of these combinatorial treatments against other viral infections. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Effects of bionic non-smooth surface on reducing soil resistance to disc ploughing

    Institute of Scientific and Technical Information of China (English)

    CHIRENDE; Benard; SIMALENGA; Timothy; Emmanuel

    2010-01-01

    Past researches have shown that the non-smooth body surfaces of soil burrowing animals help to reduce soil resistance. In this research, this concept of bionic non-smooth surface was applied to disc ploughs and an experiment was conducted in an indoor soil bin to find out the effects of different bionic units on reducing soil resistance to disc ploughing. Horizontal force acting on the disc plough during soil deformation was measured using a 5 kN sensor. Convex and concave bionic units were used and the material used for making convex ones is ultra high molecular weight polyethylene (UHMWPE) which is hydrophobic. From the experiment results, higher or deeper bionic units always resulted in less soil resistance. Convex bionic units gave the highest resistance reduction reaching a maximum of 19% reduction (from 1715.36 N to 1383.65 N) compared to concave bi-onic units. Also, samples with a bionic unit density of 30% gave the highest resistance reduction compared to the other two, which were either plain or had 10% density. In conclusion, the concept of bionic non-smooth units can be applied to disc ploughs in order to reduce soil resistance.

  16. Technical Note: Reducing the spin-up time of integrated surface water–groundwater models

    KAUST Repository

    Ajami, H.

    2014-12-12

    One of the main challenges in the application of coupled or integrated hydrologic models is specifying a catchment\\'s initial conditions in terms of soil moisture and depth-to-water table (DTWT) distributions. One approach to reducing uncertainty in model initialization is to run the model recursively using either a single year or multiple years of forcing data until the system equilibrates with respect to state and diagnostic variables. However, such "spin-up" approaches often require many years of simulations, making them computationally intensive. In this study, a new hybrid approach was developed to reduce the computational burden of the spin-up procedure by using a combination of model simulations and an empirical DTWT function. The methodology is examined across two distinct catchments located in a temperate region of Denmark and a semi-arid region of Australia. Our results illustrate that the hybrid approach reduced the spin-up period required for an integrated groundwater–surface water–land surface model (ParFlow.CLM) by up to 50%. To generalize results to different climate and catchment conditions, we outline a methodology that is applicable to other coupled or integrated modeling frameworks when initialization from an equilibrium state is required.

  17. Technical Note: Reducing the spin-up time of integrated surface water–groundwater models

    KAUST Repository

    Ajami, H.

    2014-06-26

    One of the main challenges in catchment scale application of coupled/integrated hydrologic models is specifying a catchment\\'s initial conditions in terms of soil moisture and depth to water table (DTWT) distributions. One approach to reduce uncertainty in model initialization is to run the model recursively using a single or multiple years of forcing data until the system equilibrates with respect to state and diagnostic variables. However, such "spin-up" approaches often require many years of simulations, making them computationally intensive. In this study, a new hybrid approach was developed to reduce the computational burden of spin-up time for an integrated groundwater-surface water-land surface model (ParFlow.CLM) by using a combination of ParFlow.CLM simulations and an empirical DTWT function. The methodology is examined in two catchments located in the temperate and semi-arid regions of Denmark and Australia respectively. Our results illustrate that the hybrid approach reduced the spin-up time required by ParFlow.CLM by up to 50%, and we outline a methodology that is applicable to other coupled/integrated modelling frameworks when initialization from equilibrium state is required.

  18. Technical Note: Reducing the spin-up time of integrated surface water–groundwater models

    Directory of Open Access Journals (Sweden)

    H. Ajami

    2014-06-01

    Full Text Available One of the main challenges in catchment scale application of coupled/integrated hydrologic models is specifying a catchment's initial conditions in terms of soil moisture and depth to water table (DTWT distributions. One approach to reduce uncertainty in model initialization is to run the model recursively using a single or multiple years of forcing data until the system equilibrates with respect to state and diagnostic variables. However, such "spin-up" approaches often require many years of simulations, making them computationally intensive. In this study, a new hybrid approach was developed to reduce the computational burden of spin-up time for an integrated groundwater-surface water-land surface model (ParFlow.CLM by using a combination of ParFlow.CLM simulations and an empirical DTWT function. The methodology is examined in two catchments located in the temperate and semi-arid regions of Denmark and Australia respectively. Our results illustrate that the hybrid approach reduced the spin-up time required by ParFlow.CLM by up to 50%, and we outline a methodology that is applicable to other coupled/integrated modelling frameworks when initialization from equilibrium state is required.

  19. The cosmological significance of Low Surface Brightness galaxies found in a deep blind neutral-hydrogen survey

    CERN Document Server

    Minchin, R F; Parker, Q A; Boyce, P J; De Blok, W J G; Banks, G D; Ekers, R D; Freeman, K C; García, D A; Gibson, B K; Grossi, M; Haynes, R F; Knezek, P M; Lang, R H; Malin, D F; Price, R M; Putman, M E; Stewart, I M; Wright, A E

    2004-01-01

    We have placed limits on the cosmological significance of gas-rich low surface-brightness (LSB) galaxies as a proportion of the total population of gas-rich galaxies by carrying out a very deep survey (HIDEEP) for neutral hydrogen (HI) with the Parkes multibeam system. Such a survey avoids the surface-brightness selection effects that limit the usefulness of optical surveys for finding LSB galaxies. To complement the HIDEEP survey we have digitally stacked eight 1-hour R-band Tech Pan films from the UK Schmidt Telescope covering 36 square degrees of the survey area to reach a very deep isophotal limit of 26.5 R mag/sq. arcsec. At this level, we find that all of the 129 HI sources within this area have optical counterparts and that 107 of them can be identified with individual galaxies. We have used the properties of the galaxies identified as the optical counterparts of the HI sources to estimate the significance of LSB galaxies (defined to be those at least 1.5 magnitudes dimmer in effective surface-brightne...

  20. Involvement of the PRKCB1 gene in autistic disorder: significant genetic association and reduced neocortical gene expression.

    Science.gov (United States)

    Lintas, C; Sacco, R; Garbett, K; Mirnics, K; Militerni, R; Bravaccio, C; Curatolo, P; Manzi, B; Schneider, C; Melmed, R; Elia, M; Pascucci, T; Puglisi-Allegra, S; Reichelt, K-L; Persico, A M

    2009-07-01

    Protein kinase C enzymes play an important role in signal transduction, regulation of gene expression and control of cell division and differentiation. The fsI and betaII isoenzymes result from the alternative splicing of the PKCbeta gene (PRKCB1), previously found to be associated with autism. We performed a family-based association study in 229 simplex and 5 multiplex families, and a postmortem study of PRKCB1 gene expression in temporocortical gray matter (BA41/42) of 11 autistic patients and controls. PRKCB1 gene haplotypes are significantly associated with autism (Pautism-associated alleles displayed mRNA levels comparable to those of controls. Whole genome expression analysis unveiled a partial disruption in the coordinated expression of PKCbeta-driven genes, including several cytokines. These results confirm the association between autism and PRKCB1 gene variants, point toward PKCbeta roles in altered epithelial permeability, demonstrate a significant downregulation of brain PRKCB1 gene expression in autism and suggest that it could represent a compensatory adjustment aimed at limiting an ongoing dysreactive immune process. Altogether, these data underscore potential PKCbeta roles in autism pathogenesis and spur interest in the identification and functional characterization of PRKCB1 gene variants conferring autism vulnerability.

  1. Reduced expression of the long non-coding RNA AI364715 in gastric cancer and its clinical significance.

    Science.gov (United States)

    Zhu, Shengqian; Mao, Jinqin; Shao, Yongfu; Chen, Fang; Zhu, Xiaoqin; Xu, Dingli; Zhang, Xinjun; Guo, Junming

    2015-09-01

    Long non-coding RNA (lncRNA), which is greater than 200 nucleotides, is a class of RNA molecules without protein coding function. In recent years, studies have shown that lncRNAs are associated with cancers. They are affecting the occurrence and development of cancers. However, the diagnostic significances of lncRNAs in gastric cancer are largely unknown. In this study, we focused on AI364715, one typical lncRNA. A total of 186 samples were collected from two cancer centers. To find the potential association between its level and gastric cancer, we first collected 75 paired gastric cancer tissues and normal tissues, which are 5 cm away from the edge of carcinoma. Besides, 18 human healthy gastric mucosa and 18 gastric precancerous lesions (dysplasia) were also collected. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) was first used to detect the expression level of AI364715 at multiple stages of gastric tumorigenesis. Then, the relationships between AI364715 level and the clinicopathological factors of patients with gastric cancer were analyzed. The results showed that the expression level of AI364715 in gastric cancer tissues was downregulated. Meanwhile, its expression level was closely associated with tumor size and differentiation. More importantly, AI364715 expression level was significantly changed in dysplasia, the typical precancerous lesions. Taken together, AI364715 may be a potential biomarker for the diagnosis of gastric cancer.

  2. Anti-Helicobacter pylori therapy significantly reduces Helicobacter pylori-induced gastric mucosal damage in Mongolian gerbils

    Institute of Scientific and Technical Information of China (English)

    Chun-Chao Chang; Sheng-Hsuan Chen; Gi-Shih Lien; Yuarn-Jang Lee; Horng-Yuan Lou; Ching-Ruey Hsieh; Chia-Lang Fang; Shiann Pan

    2005-01-01

    AIM: To investigate the effectiveness of 4 d' anti-Helicobacter pyloritherapy on the H pylori-infected Mongolian gerbils based on physiological and pathological changes.METHODS: We used 6-wk-old male gerbils orally inoculated with H pylori (ATCC43504, 2x108 CFU/mL).Seven weeks after H pylori inoculation, the animals of study group received 4 d' anti-H pylori triple therapy (H pylorieradicated group). Seven days later, all animals of the H pylori-eradicated and control groups (H pylori-infected& H pylori-uninfected groups) were sacrificed. We examined gastric mucosal lesions macroscopically, studied gastritis microscopically and determined the stomach weight ratio, myeloperoxidase (MPO) activity and prostaglandin (PG) E2 level.RESULTS: The results showed that both macroscopic and histological gastric damages were significantly less in H pylori-eradicated group than H pylori-infected group.Stomach weight ratio, MPO activity and PGE2 levels were significantly higher in H pylori-infected group than those in the other two groups.CONCLUSION: Four days' anti-H pylori therapy was effective in the improvement of H pylori-induced gastric lesions in Mongolian gerbils.

  3. Surface-Based fMRI-Driven Diffusion Tractography in the Presence of Significant Brain Pathology: A Study Linking Structure and Function in Cerebral Palsy

    Science.gov (United States)

    Cunnington, Ross; Boyd, Roslyn N.; Rose, Stephen E.

    2016-01-01

    Diffusion MRI (dMRI) tractography analyses are difficult to perform in the presence of brain pathology. Automated methods that rely on cortical parcellation for structural connectivity studies often fail, while manually defining regions is extremely time consuming and can introduce human error. Both methods also make assumptions about structure-function relationships that may not hold after cortical reorganisation. Seeding tractography with functional-MRI (fMRI) activation is an emerging method that reduces these confounds, but inherent smoothing of fMRI signal may result in the inclusion of irrelevant pathways. This paper describes a novel fMRI-seeded dMRI-analysis pipeline based on surface-meshes that reduces these issues and utilises machine-learning to generate task specific white matter pathways, minimising the requirement for manually-drawn ROIs. We directly compared this new strategy to a standard voxelwise fMRI-dMRI approach, by investigating correlations between clinical scores and dMRI metrics of thalamocortical and corticomotor tracts in 31 children with unilateral cerebral palsy. The surface-based approach successfully processed more participants (87%) than the voxel-based approach (65%), and provided significantly more-coherent tractography. Significant correlations between dMRI metrics and five clinical scores of function were found for the more superior regions of these tracts. These significant correlations were stronger and more frequently found with the surface-based method (15/20 investigated were significant; R2 = 0.43–0.73) than the voxelwise analysis (2 sig. correlations; 0.38 & 0.49). More restricted fMRI signal, better-constrained tractography, and the novel track-classification method all appeared to contribute toward these differences. PMID:27487011

  4. Microstructuring the surface of silicon carbide ceramic by laser action for reducing friction losses in rolling bearings

    Science.gov (United States)

    Murzin, Serguei P.; Balyakin, Valeriy B.

    2017-02-01

    A possibility of microstructuring the surface of silicon carbide ceramic by pulse-periodic laser treatment was determined for reducing the coefficient of friction under actual contact stress conditions that occur in elements of the rolling bearing in operation. Temperature rate conditions for the laser treatment with pulse duration in the millisecond range were found, which lead to a change in the surface microrelief of silicon carbide ceramic obtained by diamond grinding after hot isostatic pressing. The determination of the coefficient of sliding friction was conducted with using the ball-on-disk tribometer at normal loads, which corresponds to the values of contact stresses of (0.5-1)×109 Pa. When the load was increased to the upper limit of measuring range, the friction coefficient decrease after laser treatment was more than 30% compared to the initial structure. Significant reduction of friction in rolling bearings up to this level provides an opportunity to improve efficiency of various machines.

  5. A novel multi-stage subunit vaccine against paratuberculosis induces significant immunity and reduces bacterial burden in tissues (P4304)

    DEFF Research Database (Denmark)

    Thakur, Aneesh; Aagaard, Claus; Riber, Ulla;

    2013-01-01

    Effective control of paratuberculosis is hindered by lack of a vaccine preventing infection, transmission and without diagnostic interference with tuberculosis. We have developed a novel multi-stage recombinant subunit vaccine in which a fusion of four early expressed MAP antigens is combined...... with a MAP protein expressed in latent infection (FET11 vaccine). FET11 vaccine proteins were formulated with CAF01 adjuvant and injected to MAP challenged calves at two different ages. 28 calves divided into two FET11 vaccine groups, a commercial vaccine and a control group were used in the study...... and followed for a year. The FET11 vaccine induced a significant T cell response against constituent vaccine proteins characterized by a high percentage of CD4+ T cells and participation of polyfunctional CD4+ T cells. Of the two different age groups, late FET11 vaccination conferred protective immunity...

  6. Matching for the nonconventional MHC-I MICA gene significantly reduces the incidence of acute and chronic GVHD.

    Science.gov (United States)

    Carapito, Raphael; Jung, Nicolas; Kwemou, Marius; Untrau, Meiggie; Michel, Sandra; Pichot, Angélique; Giacometti, Gaëlle; Macquin, Cécile; Ilias, Wassila; Morlon, Aurore; Kotova, Irina; Apostolova, Petya; Schmitt-Graeff, Annette; Cesbron, Anne; Gagne, Katia; Oudshoorn, Machteld; van der Holt, Bronno; Labalette, Myriam; Spierings, Eric; Picard, Christophe; Loiseau, Pascale; Tamouza, Ryad; Toubert, Antoine; Parissiadis, Anne; Dubois, Valérie; Lafarge, Xavier; Maumy-Bertrand, Myriam; Bertrand, Frédéric; Vago, Luca; Ciceri, Fabio; Paillard, Catherine; Querol, Sergi; Sierra, Jorge; Fleischhauer, Katharina; Nagler, Arnon; Labopin, Myriam; Inoko, Hidetoshi; von dem Borne, Peter A; Kuball, Jürgen; Ota, Masao; Katsuyama, Yoshihiko; Michallet, Mauricette; Lioure, Bruno; Peffault de Latour, Régis; Blaise, Didier; Cornelissen, Jan J; Yakoub-Agha, Ibrahim; Claas, Frans; Moreau, Philippe; Milpied, Noël; Charron, Dominique; Mohty, Mohamad; Zeiser, Robert; Socié, Gérard; Bahram, Seiamak

    2016-10-13

    Graft-versus-host disease (GVHD) is among the most challenging complications in unrelated donor hematopoietic cell transplantation (HCT). The highly polymorphic MHC class I chain-related gene A, MICA, encodes a stress-induced glycoprotein expressed primarily on epithelia. MICA interacts with the invariant activating receptor NKG2D, expressed by cytotoxic lymphocytes, and is located in the MHC, next to HLA-B Hence, MICA has the requisite attributes of a bona fide transplantation antigen. Using high-resolution sequence-based genotyping of MICA, we retrospectively analyzed the clinical effect of MICA mismatches in a multicenter cohort of 922 unrelated donor HLA-A, HLA-B, HLA-C, HLA-DRB1, and HLA-DQB1 10/10 allele-matched HCT pairs. Among the 922 pairs, 113 (12.3%) were mismatched in MICA MICA mismatches were significantly associated with an increased incidence of grade III-IV acute GVHD (hazard ratio [HR], 1.83; 95% confidence interval [CI], 1.50-2.23; P < .001), chronic GVHD (HR, 1.50; 95% CI, 1.45-1.55; P < .001), and nonelapse mortality (HR, 1.35; 95% CI, 1.24-1.46; P < .001). The increased risk for GVHD was mirrored by a lower risk for relapse (HR, 0.50; 95% CI, 0.43-0.59; P < .001), indicating a possible graft-versus-leukemia effect. In conclusion, when possible, selecting a MICA-matched donor significantly influences key clinical outcomes of HCT in which a marked reduction of GVHD is paramount. The tight linkage disequilibrium between MICA and HLA-B renders identifying a MICA-matched donor readily feasible in clinical practice.

  7. Matching for the nonconventional MHC-I MICA gene significantly reduces the incidence of acute and chronic GVHD

    Science.gov (United States)

    Carapito, Raphael; Jung, Nicolas; Kwemou, Marius; Untrau, Meiggie; Michel, Sandra; Pichot, Angélique; Giacometti, Gaëlle; Macquin, Cécile; Ilias, Wassila; Morlon, Aurore; Kotova, Irina; Apostolova, Petya; Schmitt-Graeff, Annette; Cesbron, Anne; Gagne, Katia; Oudshoorn, Machteld; van der Holt, Bronno; Labalette, Myriam; Spierings, Eric; Picard, Christophe; Loiseau, Pascale; Tamouza, Ryad; Toubert, Antoine; Parissiadis, Anne; Dubois, Valérie; Lafarge, Xavier; Maumy-Bertrand, Myriam; Bertrand, Frédéric; Vago, Luca; Ciceri, Fabio; Paillard, Catherine; Querol, Sergi; Sierra, Jorge; Fleischhauer, Katharina; Nagler, Arnon; Labopin, Myriam; Inoko, Hidetoshi; von dem Borne, Peter A.; Kuball, Jürgen; Ota, Masao; Katsuyama, Yoshihiko; Michallet, Mauricette; Lioure, Bruno; Peffault de Latour, Régis; Blaise, Didier; Cornelissen, Jan J.; Yakoub-Agha, Ibrahim; Claas, Frans; Moreau, Philippe; Milpied, Noël; Charron, Dominique; Mohty, Mohamad; Zeiser, Robert; Socié, Gérard

    2016-01-01

    Graft-versus-host disease (GVHD) is among the most challenging complications in unrelated donor hematopoietic cell transplantation (HCT). The highly polymorphic MHC class I chain–related gene A, MICA, encodes a stress-induced glycoprotein expressed primarily on epithelia. MICA interacts with the invariant activating receptor NKG2D, expressed by cytotoxic lymphocytes, and is located in the MHC, next to HLA-B. Hence, MICA has the requisite attributes of a bona fide transplantation antigen. Using high-resolution sequence-based genotyping of MICA, we retrospectively analyzed the clinical effect of MICA mismatches in a multicenter cohort of 922 unrelated donor HLA-A, HLA-B, HLA-C, HLA-DRB1, and HLA-DQB1 10/10 allele-matched HCT pairs. Among the 922 pairs, 113 (12.3%) were mismatched in MICA. MICA mismatches were significantly associated with an increased incidence of grade III-IV acute GVHD (hazard ratio [HR], 1.83; 95% confidence interval [CI], 1.50-2.23; P < .001), chronic GVHD (HR, 1.50; 95% CI, 1.45-1.55; P < .001), and nonelapse mortality (HR, 1.35; 95% CI, 1.24-1.46; P < .001). The increased risk for GVHD was mirrored by a lower risk for relapse (HR, 0.50; 95% CI, 0.43-0.59; P < .001), indicating a possible graft-versus-leukemia effect. In conclusion, when possible, selecting a MICA-matched donor significantly influences key clinical outcomes of HCT in which a marked reduction of GVHD is paramount. The tight linkage disequilibrium between MICA and HLA-B renders identifying a MICA-matched donor readily feasible in clinical practice. PMID:27549307

  8. CONCENTRATION OF HARMFUL SUBSTANCES REDUCING IN SURFACE LAYER OF ATMOSPHERE AT RHEOSTAT LOCOMOTIVE TESTS

    Directory of Open Access Journals (Sweden)

    E. A. Bondar

    2010-06-01

    Full Text Available It is shown that at present an acceptable way of reducing the concentration of harmful substances in the surface layer of the atmosphere at rheostat tests of locomotives is their dispersion in a large volume of air. Channels, installed above an exhaust pipe of diesel locomotive with a break at the gas flow, work as ejectors. We have solved jointly the equation of aerodynamic characteristics of the ejector device and the equation of diffusion of gases; as a result the calculated dependence for determining the necessary height of ejector device has been obtained.

  9. Laser Surface Melting of Stainless Steel Anodes for Reduced Hydrogen Outgassing (Postprint)

    Science.gov (United States)

    2016-12-29

    carried out at atmospheric pressure under con- stant N2 flow into the capped stage (O2 levels ɘ.2%), as shown in Fig. 1. The beam expander telescope...electronic high power terahertz sources, IEEE Trans. Terahertz Sci . Technol. 1 (2011) 54–75. [4] S.D. Korovin, V.V. Rostov, S.D. Polevin, I.V. Pegel, E...9] M. Bernardini, Air bake-out to reduce hydrogen outgassing from stainless steel, J. Vac. Sci . Technol. A Vacuum, Surfaces, Film 16 (1998) 188–193.4

  10. Reduced ability to detect surface-related biofilm bacteria after antibiotic exposure under in vitro conditions

    DEFF Research Database (Denmark)

    Ravn, Christen; Furustrand Tafin, Ulrika; Bétrisey, Bertrand;

    2016-01-01

    Background and purpose - Antibiotic treatment of patients before specimen collection reduces the ability to detect organisms by culture. We investigated the suppressive effect of antibiotics on the growth of non-adherent, planktonic, and surface-related biofilm bacteria in vitro by using sonication......-dependent drugs (i.e. daptomycin and ciprofloxacin) had a strong suppressive effect on bacterial growth and reduced the ability to detect planktonic and biofilm bacteria. Exposure to rifampin rapidly caused emergence of resistance. Our findings indicate that preoperative administration of antibiotics may have...... and microcalorimetry methods. Patients and methods - Biofilms of Staphylococcus aureus, S. epidermidis, Escherichia coli, and Propionibacterium acnes were formed on porous glass beads and exposed for 24 h to antibiotic concentrations from 1 to 1,024 times the minimal inhibitory concentration (MIC) of vancomycin...

  11. Daily disinfection of high-touch surfaces in isolation rooms to reduce contamination of healthcare workers' hands.

    Science.gov (United States)

    Kundrapu, Sirisha; Sunkesula, Venkata; Jury, Lucy A; Sitzlar, Brett M; Donskey, Curtis J

    2012-10-01

    In a randomized nonblinded trial, we demonstrated that daily disinfection of high-touch surfaces in rooms of patients with Clostridium difficile infection and methicillin-resistant Staphylococcus aureus colonization reduced acquisition of the pathogens on hands after contacting high-touch surfaces and reduced contamination of hands of healthcare workers caring for the patients.

  12. Trends in significant wave height and surface wind speed in the China Seas between 1988 and 2011

    Science.gov (United States)

    Zheng, Chongwei; Zhang, Ren; Shi, Weilai; Li, Xin; Chen, Xuan

    2017-10-01

    Wind and waves are key components of the climate system as they drive air-sea interactions and influence weather systems and atmospheric circulation. In marine environments, understanding surface wind and wave fields and their evolution over time is important for conducting safe and efficient human activities, such as navigation and engineering. This study considers long-term trends in the sea surface wind speed (WS) and significant wave height (SWH) in the China Seas over the period 1988-2011 using the Cross-Calibrated Multi-Platform (CCMP) ocean surface wind product and a 24-year hindcast wave dataset obtained from the WAVEWATCH-III (WW3) wave model forced with CCMP winds. The long-term trends in WS and SWH in the China Seas are analyzed over the past 24 years to provide a reference point from which to assess future climate change and offshore wind and wave energy resource development in the region. Results demonstrate that over the period 1988-2011 in the China Seas: 1) WS and SWH showed a significant increasing trend of 3.38 cm s-1 yr-1 and 1.52 cm yr-1, respectively; 2) there were notable regional differences in the long-term trends of WS and SWH; 3) areas with strong increasing trends were located mainly in the middle of the Tsushima Strait, the northern and southern areas of the Taiwan Strait, and in nearshore regions of the northern South China Sea; and 4) the long-term trend in WS was closely associated with El Niño and a significant increase in the occurrence of gale force winds in the region.

  13. Guanine polynucleotides are self-antigens for human natural autoantibodies and are significantly reduced in the human genome.

    Science.gov (United States)

    Fattal, Ittai; Shental, Noam; Ben-Dor, Shifra; Molad, Yair; Gabrielli, Armando; Pokroy-Shapira, Elisheva; Oren, Shirly; Livneh, Avi; Langevitz, Pnina; Zandman-Goddard, Gisele; Sarig, Ofer; Margalit, Raanan; Gafter, Uzi; Domany, Eytan; Cohen, Irun R

    2015-11-01

    In the course of investigating anti-DNA autoantibodies, we examined IgM and IgG antibodies to poly-G and other oligonucleotides in the sera of healthy persons and those diagnosed with systemic lupus erythematosus (SLE), scleroderma (SSc), or pemphigus vulgaris (PV); we used an antigen microarray and informatic analysis. We now report that all of the 135 humans studied, irrespective of health or autoimmune disease, manifested relatively high amounts of IgG antibodies binding to the 20-mer G oligonucleotide (G20); no participants entirely lacked this reactivity. IgG antibodies to homo-nucleotides A20, C20 or T20 were present only in the sera of SLE patients who were positive for antibodies to dsDNA. The prevalence of anti-G20 antibodies led us to survey human, mouse and Drosophila melanogaster (fruit fly) genomes for runs of T20 and G20 or more: runs of T20 appear > 170,000 times compared with only 93 runs of G20 or more in the human genome; of these runs, 40 were close to brain-associated genes. Mouse and fruit fly genomes showed significantly lower T20/G20 ratios than did human genomes. Moreover, sera from both healthy and SLE mice contained relatively little or no anti-G20 antibodies; so natural anti-G20 antibodies appear to be characteristic of humans. These unexpected observations invite investigation of the immune functions of anti-G20 antibodies in human health and disease and of runs of G20 in the human genome.

  14. Inelastic compression legging produces gradient compression and significantly higher skin surface pressures compared with an elastic compression stocking.

    Science.gov (United States)

    Kline, Cassie N; Macias, Brandon R; Kraus, Emily; Neuschwander, Timothy B; Angle, Niren; Bergan, John; Hargens, Alan R

    2008-01-01

    The purposes of this study were to (1) investigate compression levels beneath an inelastic legging equipped with a new pressure-adjustment system, (2) compare the inelastic compression levels with those provided by a well-known elastic stocking, and (3) evaluate each support's gradient compression production. Eighteen subjects without venous reflux and 12 patients with previously documented venous reflux received elastic and inelastic compression supports sized for the individual. Skin surface pressures under the elastic (Sigvaris 500, 30-40 mm Hg range, Sigvaris, Inc., Peachtree City, GA) and inelastic (CircAid C3 with Built-in-Pressure System [BPS], CircAid Medical Products, San Diego, CA) supports were measured using a calibrated Tekscan I-Scan device (Tekscan, Inc., Boston, MA). The elastic stocking produced significantly lower skin surface pressures than the inelastic legging. Mean pressures (+/- standard error) beneath the elastic stocking were 26 +/- 2 and 23 +/- 1 mm Hg at the ankle and below-knee regions, respectively. Mean pressures (+/- standard error) beneath the inelastic legging with the BPS were 50 +/- 3 and 38 +/- 2 mm Hg at the ankle and below-knee regions, respectively. Importantly, our study indicates that only the inelastic legging with the BPS produces significant ankle to knee gradient compression (p = .001).

  15. Alloying Au surface with Pd reduces the intrinsic activity in catalyzing CO oxidation

    KAUST Repository

    Qian, Kun

    2016-03-30

    © 2016. Various Au-Pd/SiO2 catalysts with a fixed Au loading but different Au:Pd molar ratios were prepared via deposition-precipitation method followed by H2 reduction. The structures were characterized and the catalytic activities in CO oxidation were evaluated. The formation of Au-Pd alloy particles was identified. The Au-Pd alloy particles exhibit enhanced dispersions on SiO2 than Au particles. Charge transfer from Pd to Au within Au-Pd alloy particles. Isolated Pd atoms dominate the surface of Au-Pd alloy particles with large Au:Pd molar ratios while contiguous Pd atoms dominate the surface of Au-Pd alloy particles with small Au:Pd molar ratios. Few synergetic effect of Au-Pd alloy occurs on catalyzing CO oxidation under employed reaction conditions. Alloying Au with Pd reduces the intrinsic activity in catalyzing CO oxidation, and contiguous Pd atoms on the Au-Pd alloy particles are capable of catalyzing CO oxidation while isolated Pd atoms are not. These results advance the fundamental understandings of Au-Pd alloy surfaces in catalyzing CO oxidation.

  16. SiO2-nanocomposite film coating of CAD/CAM composite resin blocks improves surface hardness and reduces susceptibility to bacterial adhesion.

    Science.gov (United States)

    Kamonwanon, Pranithida; Hirose, Nanako; Yamaguchi, Satoshi; Sasaki, Jun-Ichi; Kitagawa, Haruaki; Kitagawa, Ranna; Thaweboon, Sroisiri; Srikhirin, Toemsak; Imazato, Satoshi

    2017-01-31

    Composite resin blocks for computer-aided design/computer-aided manufacturing (CAD/CAM) applications have recently become available. However, CAD/CAM composite resins have lower wear resistance and accumulate more plaque than CAD/CAM ceramic materials. We assessed the effects of SiO2-nanocomposite film coating of four types of CAD/CAM composite resin blocks: Cerasmart, Katana Avencia block, Lava Ultimate, and Block HC on surface hardness and bacterial attachment. All composite blocks with coating demonstrated significantly greater Vickers hardness, reduced surface roughness, and greater hydrophobicity than those without coating. Adhesion of Streptococcus mutans to the coated specimens was significantly less than those for the uncoated specimens. These reduced levels of bacterial adherence on the coated surface were still evident after treatment with saliva. Surface modification by SiO2-nanocomposite film coating has potential to improve wear resistance and susceptibility to plaque accumulation of CAD/CAM composite resin restorations.

  17. Multi-resistive Reduced Graphene Oxide Diode with Reversible Surface Electrochemical Reaction induced Carrier Control

    OpenAIRE

    Hyungtak Seo; Seungbae Ahn; Jinseo Kim; Young-Ahn Lee; Koo-Hyun Chung; Ki-Joon Jeon

    2014-01-01

    The extended application of graphene-based electronic devices requires a bandgap opening in order to realize the targeted device functionality. Since the bandgap tuning of pristine graphene is limited to 360 meV, the chemical modification of graphene is considered essential to achieve a large bandgap opening at the expense of electrical properties degradation. Reduced graphene oxide (RGO) has attracted significant interest for fabricating graphene-based semiconductors since it has several adv...

  18. Convection due to surface-tension gradients. [in reduced gravity spacecraft environments

    Science.gov (United States)

    Ostrach, S.

    1978-01-01

    The use of dimensionless parameters to study fluid motions that could occur in a reduced-gravity environment is discussed. The significance of the Marangoni instability is considered, and the use of dimensionless parameters to investigate problems such as thermo and diffusocapillary flows is described. Characteristics of fluid flow in space are described, and the relation and interaction of motions due to capillarity and buoyancy is examined.

  19. Back surface cell structures for reducing recombination in CZ silicon solar cells

    Science.gov (United States)

    King, R. R.; Mitchell, K. W.; Gee, J. M.

    1994-12-01

    Mass-produced terrestrial CZ silicon solar cells are currently entering the domain in which bulk diffusion length is comparable to the cell thickness, so that recombination at the back surface can have a significant effect on device performance. Three manufacturable processes that address the problem of back recombination are examined here: boron diffusion from a deposited doped SiO2, layer; Al-alloyed layers using screen-printed paste; and use of a collecting n* layer on the back interdigitated with the positive electrode. 104 sq cm cells fabricated at Siemens Solar Industries using these back surface structures are characterized by current-voltage, spectral response, photoconductivity decay, and SIMS measurements.

  20. Enhanced Fe2O3 Reducibility via Surface Modification with Pd: Characterizing the Synergy within Pd/Fe Catalysts for Hydrodeoxygenation Reactions

    Energy Technology Data Exchange (ETDEWEB)

    Hensley, Alyssa; Hong, Yongchun; Zhang, Renqin; Zhang, He; Sun, Junming; Wang, Yong; McEwen, Jean-Sabin

    2014-10-03

    The synergistic catalysis in the hydrodeoxygenation of phenolic compounds over a Pd/Fe bimetallic surface has been well established. However, the nature of this synergy is still in part a mystery. In this work, we used a combined experimental and theoretical approach to understand a potential function of the surface Pd in the reduction of Pd/Fe2O3. This function of Pd was investigated via the comparison of the reduction properties as well as other physicochemical properties of samples synthesized by the reduction of Fe2O3 nanoparticles with and without surface Pd. Temperature-programmed reduction studies demonstrated the remarkable facilitation of reduction by addition of Pd, evidenced by a 150 degrees C shift toward lower temperature of the reduction peak of Fe3+. From X-ray photoelectron spectroscopy and theoretical calculation results, the interaction between Pd and the Fe2O3 surface occurs through the exchange of electrons with both the surface Fe and O atoms. This bonding between the Pd and surface oxide elements causes the Pd to partially donate electrons to the oxide surface, making the surface electrons more delocalized. This electron delocalization stabilizes the reduced oxide surfaces, as suggested by the TPR results and theoretical prediction. Therefore, the stabilization of the reduced Fe surface as well as the facilitated water formation by introduction of Pd is expected to significantly contribute to the Pd-Fe synergy in hydrodeoxygenation catalysis.

  1. From meatless Mondays to meatless Sundays: motivations for meat reduction among vegetarians and semi-vegetarians who mildly or significantly reduce their meat intake.

    Science.gov (United States)

    De Backer, Charlotte J S; Hudders, Liselot

    2014-01-01

    This study explores vegetarians' and semi-vegetarians' motives for reducing their meat intake. Participants are categorized as vegetarians (remove all meat from their diet); semi-vegetarians (significantly reduce meat intake: at least three days a week); or light semi-vegetarians (mildly reduce meat intake: once or twice a week). Most differences appear between vegetarians and both groups of semi-vegetarians. Animal-rights and ecological concerns, together with taste preferences, predict vegetarianism, while an increase in health motives increases the odds of being semi-vegetarian. Even within each group, subgroups with different motives appear, and it is recommended that future researchers pay more attention to these differences.

  2. Modeling plant, microorganisms, and mineral surface competition for soil nitrogen and phosphorus: Competition representations and ecological significance

    Science.gov (United States)

    Zhu, Q.; Riley, W. J.; Chambers, J. Q.; Tang, J.

    2014-12-01

    It is widely accepted that terrestrial ecosystem carbon dynamics are strongly coupled and controlled by soil nutrients status. Nutrient availability serves as an indicator of aboveground carbon productivity and ecosystem stability, especially when soils are infertile. In these conditions, plants have to outcompete microorganism and mineral surfaces to acquire nutrients required for photosynthesis, respiration, seed production, defense, etc. It is usually hypothesized that microbes are short-term winners but long-term losers in nutrient competition. Microbes quickly trap available soil nitrogen and phosphorous, thereby preventing nutrient inaccessibility through hydrological leaching and mineral surface adsorption. Over longer temporal scales, nutrients are released into the soil and become available for plant uptake. Despite its ecological significance, nutrient competition is either absent or over-simplified (e.g., assuming all consumers are equally competitive) in terrestrial biogeochemistry models. Here, we aim to test the representation of different competitive strategies and to investigate their ecological consequences with a newly developed biogeochemical model structure. The new model includes three major soil nutrients (ammonia, nitrate, and phosphate) and multiple consumers (plants, microbes, mineral surfaces, nitrifiers, and denitrifiers). We analyze predicted soil carbon, nitrogen, and phosphorus dynamics with three different competitive strategies: (1) plants compete poorly against microorganisms; (2) all consumers are equally competitive; and (3) an explicit Equilibrium Chemical Approximation (ECA; Tang and Riley (2013)) treatment. We find that very different ecosystem states are predicted when assuming different competitive structures, and that the ECA approach provides the best match with a large suite of observational constraints from tropical experimental and transect studies. We conclude that terrestrial biogeochemical models should represent a

  3. The seasonal variations in the significant wave height and sea surface wind speed of the China’s seas

    Institute of Scientific and Technical Information of China (English)

    ZHENG Chongwei; PAN Jing; TAN Yanke; GAO Zhansheng; RUI Zhenfeng; CHEN Chaohui

    2015-01-01

    Long-term variations in a sea surface wind speed (WS) and a significant wave height (SWH) are associated with the global climate change, the prevention and mitigation of natural disasters, and an ocean resource exploitation, and other activities. The seasonal characteristics of the long-term trends in China’s seas WS and SWH are determined based on 24 a (1988–2011) cross-calibrated, multi-platform (CCMP) wind data and 24 a hindcast wave data obtained with the WAVEWATCH-III (WW3) wave model forced by CCMP wind data. The results show the following. (1) For the past 24 a, the China’s WS and SWH exhibit a significant increasing trend as a whole, of 3.38 cm/(s·a) in the WS, 1.3 cm/a in the SWH. (2) As a whole, the increasing trend of the China’s seas WS and SWH is strongest in March-April-May (MAM) and December-January-February (DJF), followed by June-July-August (JJA), and smallest in September-October-November (SON). (3) The areal extent of significant increases in the WS was largest in MAM, while the area decreased in JJA and DJF;the smallest area was apparent in SON. In contrast to the WS, almost all of China’s seas exhibited a significant increase in SWH in MAM and DJF;the range was slightly smaller in JJA and SON. The WS and SWH in the Bohai Sea, the Yellow Sea, East China Sea, the Tsushima Strait, the Taiwan Strait, the northern South China Sea, the Beibu Gulf, and the Gulf of Thailand exhibited a significant increase in all seasons. (4) The variations in China’s seas SWH and WS depended on the season. The areas with a strong increase usually appeared in DJF.

  4. Surface Modification of Fine Particle by Plasma Grafting in a Circulating Fluidized Bed Reactor under Reduced Pressure

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sounghee [Woosuk University, Jinchon (Korea, Republic of)

    2015-10-15

    A plasma surface modification of powders has been carried out in a circulating fluidized bed reactor under reduced pressure. Polystyrene (PS) particles treated by plasma are grafted with polyethylene glycol (PEG) on the surface. The virgin, plasma-treated and grafted powders were characterized by DPPH method, FTIR, SEM and contact angle meter. The plasma-treated PS powders have well formed peroxide on the surface, By PEG grafting polymerization, PEG is well grafted and dispersed on the surface of the plasma-treated PS powders. The PEG-g-PS particle was successfully synthesized using the plasma circulating fluidized bed reactor under reduced pressure.

  5. Reduced glass transition temperatures in thin polymer films: surface effect or artifact?

    Science.gov (United States)

    Bäumchen, O; McGraw, J D; Forrest, J A; Dalnoki-Veress, K

    2012-08-03

    We have examined the direct effect of manipulating the number of free surfaces on the measured glass transition temperature T(g) of thin polystyrene films. Thin films in the range 35 nm thickness and refractive index of freestanding films. By noting the change in slope in each of these quantities, a T(g) value can be assigned in quantitative agreement with previously reported results. For thin freestanding films this value is reduced from that of the bulk. The exact same films are then transferred to a Si substrate and the T(g) of the resulting supported film was determined. The T(g) values of the now supported films are the same as the bulk value and the same as previous reports of similar supported films. These experiments unambiguously show that free interfaces are the dominant cause of the T(g) reductions for the film thicknesses studied.

  6. Differential microstrip lines with reduced crosstalk and common mode effect based on spoof surface plasmon polaritons.

    Science.gov (United States)

    Wu, Jin Jei; Hou, Da Jun; Liu, Kexin; Shen, Linfang; Tsai, Chi An; Wu, Chien Jang; Tsai, Dichi; Yang, Tzong-Jer

    2014-11-03

    We apply the concept of spoof surface plasmon polaritons (SPPs) to the design of differential microstrip lines by introducing periodic subwavelength corrugations on their edges. The dispersion relation and field distribution of those lines are analyzed numerically. And then through designing practical coupling circuits, we found that compared with conventional differential microstrip lines, the electromagnetic field can be strongly confined inside the grooves of the corrugated microstrip lines, so the crosstalk between the differential pair and the adjacent microstrip lines is greatly reduced, and the conversion from the differential signal to the common mode signal can also be effectively suppressed. The propagation length of those lines is also very long in a wide band. Moreover, the experimental results in time domain demonstrate those lines perform very well in high-speed circuit. Therefore, those novel kinds of spoof SPPs based differential microstrip lines can be widely utilized in high-density microwave circuits and guarantee signal integrity in high-speed systems.

  7. Chronic Morphine Reduces Surface Expression of δ-Opioid Receptors in Subregions of Rostral Striatum.

    Science.gov (United States)

    Leah, Paul M; Heath, Emily M L; Balleine, Bernard W; Christie, Macdonald J

    2016-03-01

    The delta opioid receptor (DOPr), whilst not the primary target of clinically used opioids, is involved in development of opioid tolerance and addiction. There is growing evidence that DOPr trafficking is involved in drug addiction, e.g., a range of studies have shown increased plasma membrane DOPr insertion during chronic treatment with opioids. The present study used a transgenic mouse model in which the C-terminal of the DOPr is tagged with enhanced-green fluorescence protein to examine the effects of chronic morphine treatment on surface membrane expression in striatal cholinergic interneurons that are implicated in motivated learning following both chronic morphine and morphine sensitization treatment schedules in male mice. A sex difference was noted throughout the anterior striatum, which was most prominent in the nucleus accumbens core region. Incontrast with previous studies in other neurons, chronic exposure to a high dose of morphine for 6 days had no effect, or slightly decreased (anterior dorsolateral striatum) surface DOPr expression. A morphine sensitization schedule produced similar results with a significant decrease in surface DOPr expression in nucleus accumbens shell. These results suggest that chronic morphine and morphine sensitisation treatment may have effects on instrumental reward-seeking behaviours and learning processes related to drug addiction, via effects on striatal DOPr function.

  8. Significant performance enhancement of InGaN/GaN nanorod LEDs with multi-layer graphene transparent electrodes by alumina surface passivation.

    Science.gov (United States)

    Latzel, M; Büttner, P; Sarau, G; Höflich, K; Heilmann, M; Chen, W; Wen, X; Conibeer, G; Christiansen, S H

    2017-02-03

    Nanotextured surfaces provide an ideal platform for efficiently capturing and emitting light. However, the increased surface area in combination with surface defects induced by nanostructuring e.g. using reactive ion etching (RIE) negatively affects the device's active region and, thus, drastically decreases device performance. In this work, the influence of structural defects and surface states on the optical and electrical performance of InGaN/GaN nanorod (NR) light emitting diodes (LEDs) fabricated by top-down RIE of c-plane GaN with InGaN quantum wells was investigated. After proper surface treatment a significantly improved device performance could be shown. Therefore, wet chemical removal of damaged material in KOH solution followed by atomic layer deposition of only 10 [Formula: see text] alumina as wide bandgap oxide for passivation were successfully applied. Raman spectroscopy revealed that the initially compressively strained InGaN/GaN LED layer stack turned into a virtually completely relaxed GaN and partially relaxed InGaN combination after RIE etching of NRs. Time-correlated single photon counting provides evidence that both treatments-chemical etching and alumina deposition-reduce the number of pathways for non-radiative recombination. Steady-state photoluminescence revealed that the luminescent performance of the NR LEDs is increased by about 50% after KOH and 80% after additional alumina passivation. Finally, complete NR LED devices with a suspended graphene contact were fabricated, for which the effectiveness of the alumina passivation was successfully demonstrated by electroluminescence measurements.

  9. Significant performance enhancement of InGaN/GaN nanorod LEDs with multi-layer graphene transparent electrodes by alumina surface passivation

    Science.gov (United States)

    Latzel, M.; Büttner, P.; Sarau, G.; Höflich, K.; Heilmann, M.; Chen, W.; Wen, X.; Conibeer, G.; Christiansen, S. H.

    2017-02-01

    Nanotextured surfaces provide an ideal platform for efficiently capturing and emitting light. However, the increased surface area in combination with surface defects induced by nanostructuring e.g. using reactive ion etching (RIE) negatively affects the device’s active region and, thus, drastically decreases device performance. In this work, the influence of structural defects and surface states on the optical and electrical performance of InGaN/GaN nanorod (NR) light emitting diodes (LEDs) fabricated by top-down RIE of c-plane GaN with InGaN quantum wells was investigated. After proper surface treatment a significantly improved device performance could be shown. Therefore, wet chemical removal of damaged material in KOH solution followed by atomic layer deposition of only 10 {nm} alumina as wide bandgap oxide for passivation were successfully applied. Raman spectroscopy revealed that the initially compressively strained InGaN/GaN LED layer stack turned into a virtually completely relaxed GaN and partially relaxed InGaN combination after RIE etching of NRs. Time-correlated single photon counting provides evidence that both treatments—chemical etching and alumina deposition—reduce the number of pathways for non-radiative recombination. Steady-state photoluminescence revealed that the luminescent performance of the NR LEDs is increased by about 50% after KOH and 80% after additional alumina passivation. Finally, complete NR LED devices with a suspended graphene contact were fabricated, for which the effectiveness of the alumina passivation was successfully demonstrated by electroluminescence measurements.

  10. High-Surface-Area Nitrogen-Doped Reduced Graphene Oxide for Electric Double-Layer Capacitors.

    Science.gov (United States)

    Youn, Hee-Chang; Bak, Seong-Min; Kim, Myeong-Seong; Jaye, Cherno; Fischer, Daniel A; Lee, Chang-Wook; Yang, Xiao-Qing; Roh, Kwang Chul; Kim, Kwang-Bum

    2015-06-08

    A two-step method consisting of solid-state microwave irradiation and heat treatment under NH3 gas was used to prepare nitrogen-doped reduced graphene oxide (N-RGO) with a high specific surface area (1007 m(2)  g(-1) ), high electrical conductivity (1532 S m(-1) ), and low oxygen content (1.5 wt %) for electrical double-layer capacitor applications. The specific capacitance of N-RGO was 291 F g(-1) at a current density of 1 A g(-1) , and a capacitance of 261 F g(-1) was retained at 50 A g(-1) , which indicated a very good rate capability. N-RGO also showed excellent cycling stability and preserved 96 % of the initial specific capacitance after 100 000 cycles. Near-edge X-ray absorption fine-structure spectroscopy results provided evidenced for the recovery of π conjugation in the carbon networks with the removal of oxygenated groups and revealed chemical bonding of the nitrogen atoms in N-RGO. The good electrochemical performance of N-RGO is attributed to its high surface area, high electrical conductivity, and low oxygen content.

  11. Surface characteristics of coated polyester fabric with reduced graphene oxide and polypyrrole

    Energy Technology Data Exchange (ETDEWEB)

    Berendjchi, Amirhosein [Department of Textile Engineering, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Khajavi, Ramin, E-mail: khajavi@azad.ac.ir [Nano Technology Research Center, South Tehran Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Yousefi, Ali Akbar [Faculty of Polymer Processing, Iran Polymer and Petrochemical Institute, Tehran (Iran, Islamic Republic of); Yazdanshenas, Mohammad Esmail [Department of Textile Engineering, Yazd Branch, Islamic Azad University, Yazd (Iran, Islamic Republic of)

    2016-03-30

    Graphical abstract: - Highlights: • PET in form of film or membrane is hydrophobic and its wetting behavior follows the Wenzel wetting theory. In the form of textile materials it shows hydrophilicity. • rGO coated PET fabric shows hydrophobicity and its wetting behavior places between Wenzel and Cassie–Baxter models. • PET coated fabric by PPy shows superhydrophobicity and its wetting behavior is consistence with Cassie–Baxter model. • Due to oxidation of the rGO during in situ synthesis of PPy the rGO–PPy coated PET shows hydrophilicity. - Abstract: In this study, the influence of coating polyethylene terephthalate (PET) fabric with reduced graphene oxide (rGO) and polypyrrole (PPy), individually or in combination (rGO–PPy), on surface chemistry and roughness (focusing on wetting behavior), were analyzed systematically. Characterization was carried out by observing the topography (atomic force microscopy – AFM) and stating surface analysis (X-ray photoelectron spectroscopy – XPS), contact angles (goniometry), water shedding angles, and surface energy values of the samples. The results showed that the contact angles of pristine (uncoated), GO and rGO–PPy coated samples were 0°, while it was 92°, 123° and 151° for hot pressed (2nd pristine sample), rGO and PPy samples, respectively. A zero contact angle for PET sample was due to its wicking ability. Results were interpreted with Young, Wenzel and Cassie Baxter equations. It was found that PPy coated samples were consistent with Cassie–Baxter equation, while rGO placed between Wenzel and Cassie–Baxter wetting models.

  12. Reduced dimensionality spin-orbit dynamics of CH3 + HCl ⇌ CH4 + Cl on ab initio surfaces.

    Science.gov (United States)

    Remmert, Sarah M; Banks, Simon T; Harvey, Jeremy N; Orr-Ewing, Andrew J; Clary, David C

    2011-05-28

    A reduced dimensionality quantum scattering method is extended to the study of spin-orbit nonadiabatic transitions in the CH(3) + HCl ⇌ CH(4) + Cl((2)P(J)) reaction. Three two-dimensional potential energy surfaces are developed by fitting a 29 parameter double-Morse function to CCSD(T)/IB//MP2/cc-pV(T+d)Z-dk ab initio data; interaction between surfaces is described by geometry-dependent spin-orbit coupling functions fit to MCSCF/cc-pV(T+d)Z-dk ab initio data. Spectator modes are treated adiabatically via inclusion of curvilinear projected frequencies. The total scattering wave function is expanded in a vibronic basis set and close-coupled equations are solved via R-matrix propagation. Ground state thermal rate constants for forward and reverse reactions agree well with experiment. Multi-surface reaction probabilities, integral cross sections, and initial-state selected branching ratios all highlight the importance of vibrational energy in mediating nonadiabatic transition. Electronically excited state dynamics are seen to play a small but significant role as consistent with experimental conclusions.

  13. Optimization of Reducing Sugar Production from Manihot glaziovii Starch Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Abdi Hanra Sebayang

    2017-01-01

    Full Text Available Bioethanol is known as a viable alternative fuel to solve both energy and environmental crises. This study used response surface methodology based on the Box-Behnken experimental design to obtain the optimum conditions for and quality of bioethanol production. Enzymatic hydrolysis optimization was performed with selected hydrolysis parameters, including substrate loading, stroke speed, α-amylase concentration and amyloglucosidase concentration. From the experiment, the resulting optimum conditions are 23.88% (w/v substrate loading, 109.43 U/g α-amylase concentration, 65.44 U/mL amyloglucosidase concentration and 74.87 rpm stroke speed, which yielded 196.23 g/L reducing sugar. The fermentation process was also carried out, with a production value of 0.45 g ethanol/g reducing sugar, which is equivalent to 88.61% of ethanol yield after fermentation by using Saccharomyces cerevisiae (S. cerevisiae. The physical and chemical properties of the produced ethanol are within the specifications of the ASTM D4806 standard. The good quality of ethanol produced from this study indicates that Manihot glaziovii (M. glaziovii has great potential as bioethanol feedstock.

  14. REDUCING SURFACE TEMPERATURES OF NORTH-SOUTH BUSINESS CORRIDORS IN YOGYAKARTA

    Directory of Open Access Journals (Sweden)

    Prasasto SATWIKO

    2015-12-01

    Full Text Available The heat island has made the warm-humid climate city of Yogyakarta thermally more uncomfortable, which induces its people to depend more on energy consuming air conditioners. Business corridors are constructed from building walls and roofs, pedestrian paths, the streets and the vegetation, which convert solar radiation into heat. Infrared mappings of the four north-south axis business corridors of Yogyakarta found that streets and vehicles have their temperatures higher than the air temperature. Exception is at Gejayan St., where the street’s temperature is close to the air temperature. This street has rows of trees on its median, which effectively shades the street. Further study on Gejayan St. using a computer simulation method confirms that columnar and spreading form trees can reduce incident solar radiation on the street surface by, respectively, 13.35% and 22.02%. Putting creeping plants on pergolas reduce incident solar radiation on the west and the east walls by, respectively, 37.05% and 37.45%.

  15. Varying protein source and quantity does not significantly improve weight loss, fat loss, or satiety in reduced energy diets among midlife adults

    Science.gov (United States)

    This pilot study tested whether varying protein source and quantity in a reduced energy diet would result in significant differences in weight, body composition, and renin angiotensin aldosterone system activity in midlife adults. Eighteen subjects enrolled in a 5 month weight reduction study, invol...

  16. Particulate Bioglass reduces the viability of bacterial biofilms formed on its surface in an in vitro model.

    Science.gov (United States)

    Allan, Iain; Newman, Hubert; Wilson, Michael

    2002-02-01

    45S5 Bioglass is a bioactive implant material which, in its particulate form, is used in the repair of periodontal defects. The surface reactions undergone by this material in an aqueous environment may exert an antibacterial effect that would be beneficial to periodontal surgical treatment. Biofilms of Streptococcus sanguis, an early plaque former, and mixed species biofilms from a salivary inoculum grown under conditions similar to those associated with periodontal implants, were grown on particulate Bioglass in a constant depth film fermenter (CDFF). Control biofilms were grown on inert glass particulates. At sample times of 3, 24 and 48 hours the viability of biofilms of S. sanguis grown on Bioglass was significantly lower than for those grown on inert glass. In the experiments with subgingivally-modelled mixed species biofilms, the total anaerobic counts were significantly lower on Bioglass after 24 and 48 hours, but not 96 or 168 hours, compared to inert glass. Thus, particulate Bioglass has the potential to reduce bacterial colonisation of its surface in vivo, a feature relevant to post-surgical periodontal wound healing.

  17. Estimation of Land Surface Energy Balance Using Satellite Data of Spatial Reduced Resolution

    Science.gov (United States)

    Vintila, Ruxandra; Radnea, Cristina; Savin, Elena; Poenaru, Violeta

    2010-12-01

    The paper presents preliminary results concerning the monitoring at national level of several geo-biophysical variables retrieved by remote sensing, in particular those related to drought or aridisation. The study, which is in progress, represents also an exercise for to the implementation of a Land Monitoring Core Service for Romania, according to the Kopernikus Program and in compliance with the INSPIRE Directive. The SEBS model has been used to retrieve land surface energy balance variables, such as turbulent heat fluxes, evaporative fraction and daily evaporation, based on three information types: (1) surface albedo, emissivity, temperature, fraction of vegetation cover (fCover), leaf area index (LAI) and vegetation height; (2) air pressure, temperature, humidity and wind speed at the planetary boundary layer (PBL) height; (3) downward solar radiation and downward longwave radiation. AATSR and MERIS archived reprocessed images have provided several types of information. Thus, surface albedo, emissivity, and land surface temperature have been retrieved from AATSR, while LAI and fCover have been estimated from MERIS. The vegetation height has been derived from CORINE Land Cover and PELCOM Land Use databases, while the meteorological information at the height of PBL have been estimated from the measurements provided by the national weather station network. Other sources of data used during this study have been the GETASSE30 digital elevation model with 30" spatial resolution, used for satellite image orthorectification, and the SIGSTAR-200 geographical information system of soil resources of Romania, used for water deficit characterisation. The study will continue by processing other AATSR and MERIS archived images, complemented by the validation of SEBS results with ground data collected on the most important biomes for Romania at various phenological stages, and the transformation of evaporation / evapotranspiration into a drought index using the soil texture

  18. Age, distribution, and significance within a sediment budget, of in-channel depositional surfaces in the Normanby River, Queensland, Australia

    Science.gov (United States)

    Pietsch, T. J.; Brooks, A. P.; Spencer, J.; Olley, J. M.; Borombovits, D.

    2015-06-01

    We present the results of investigations into alluvial deposition in the catchment of the Normanby River, which flows into Princess Charlotte Bay (PCB) in the northern part of the Great Barrier Reef Lagoon. Our focus is on the fine fraction (expansive flat surface generally referred to as the floodplain. Variously described as benches, bank attached bars or inset or inner floodplains, these more or less flat-lying surfaces within the macro-channel have hitherto received little attention in sediment budgeting models. We use high resolution LiDAR based mapping combined with optical dating of exposures cut into these in-channel deposits to compare their aggradation rates with those found in other depositional zones in the catchment, namely the floodplain and coastal plain. In total 59 single grain OSL dates were produced across 21 stratigraphic profiles at 14 sites distributed though the 24 226 km2 catchment. In-channel storage in these inset features is a significant component of the contemporary fine sediment budget (i.e. recent decades/last century), annually equivalent to more than 50% of the volume entering the channel network from hillslopes and subsoil sources. Therefore, at the very least, in-channel storage of fine material needs to be incorporated into sediment budgeting exercises. Furthermore, deposition within the channel has occurred in multiple locations coincident in time with accelerated sediment production following European settlement. Generally, this has occurred on a subset of the features we have examined here, namely linear bench features low in the channel. This suggests that accelerated aggradation on in-channel depositional surfaces has been in part a response to accelerated erosion within the catchment. The entire contribution of ~ 370 kilotonnes per annum of fine sediment estimated to have been produced by alluvial gully erosion over the last ~ 100 years can be accounted for by that stored as in-channel alluvium. These features therefore can

  19. Inactivation of baculovirus by isoflavonoids on chickpea (Cicer arietinum) leaf surfaces reduces the efficacy of nucleopolyhedrovirus against Helicoverpa armigera.

    Science.gov (United States)

    Stevenson, Philip C; D'Cunha, Reju F; Grzywacz, David

    2010-02-01

    Biological pesticides based on nucleopolyhedroviruses (NPVs) can provide an effective and environmentally benign alternative to synthetic chemicals. On some crops, however, the efficacy and persistence of NPVs is known to be reduced by plant specific factors. The present study investigated the efficacy of Helicoverpa armigera NPV (HearNPV) for control of H. armigera larvae, and showed that chickpea reduced the infectivity of virus occlusion bodies (OBs) exposed to the leaf surface of chickpea for at least 1 h. The degree of inactivation was greater on chickpea than that previously reported on cotton, and the mode of action is different from that of cotton. The effect was observed for larvae that consumed OBs on chickpea leaves, but it also occurred when OBs were removed after exposure to plants and inoculated onto artificial diet, indicating that inhibition was leaf surface-related and permanent. Despite their profuse exudation from trichomes on chickpea leaves and their low pH, organic acids-primarily oxalic and malic acid-caused no inhibition. When HearNPV was incubated with biochanin A and sissotrin, however, two minor constituents of chickpea leaf extracts, OB activity was reduced significantly. These two isoflavonoids increased in concentration by up to 3 times within 1 h of spraying the virus suspension onto the plants and also when spraying only the carrier, indicating induction was in response to spraying and not a specific response to the HearNPV. Although inactivation by the isoflavonoids did not account completely for the level of effect recorded on whole plants, this work constitutes evidence for a novel mechanism of NPV inactivation in legumes. Expanding the use of biological pesticides on legume crops will be dependent upon the development of suitable formulations for OBs to overcome plant secondary chemical effects.

  20. Evaluation of a denitrification wall to reduce surface water nitrogen loads.

    Science.gov (United States)

    Schmidt, Casey A; Clark, Mark W

    2012-01-01

    Denitrification walls have significantly reduced nitrogen concentrations in groundwater for at least 15 yr. This has spurred interest in developing methods to efficiently increase capture volume to reduce N loads in larger watersheds. The objective of this study was to maximize treatment volume by locating a wall where a large groundwatershed was funneled toward seepage slope headwaters. Nitrogen concentration and load were measured before and after wall installation in paired treatment and control streams. Beginning 2 d after installation, nitrogen concentration in the treatment stream declined from 6.7 ± 1.2 to 3.9 ± 0.78 mg L and total N loading rate declined by 65% (391 kg yr) with no corresponding decline in the control watershed. This wall, which only comprised 10 to 11% of the edge of field area that contributed to the treatment watershed, treated approximately 60% of the stream discharge, which confirmed the targeted approach. The total load reduction measured in the stream 155 m downstream from the wall (340 kg yr) was higher than that found in another study that measured load reductions in groundwater wells immediately around the wall (228 kg yr). This indicated the possibility of an extended impact on denitrification from carbon exported beyond the wall. This extended impact was inauspiciously confirmed when oxygen levels at the stream headwaters temporarily declined for 50 d. This research indicates that targeting walls adjacent to streams can effectively reduce N loading in receiving waters, although with a potentially short-term impact on water quality.

  1. Predicting the effects of measures to reduce eutrophication in surface water in rural areas - a case study

    NARCIS (Netherlands)

    Hendriks, R.F.A.; Kolk, van der J.W.H.

    1995-01-01

    The effectiveness of measures to reduce nutrient concentrations in surface water was predicted by a combination of a nutrient leaching model for groundwater and a nutrient simulation model for surface water. Scenarios were formulated based on several measures. Different combinations of drainage

  2. Volcanic ash supply to the surface ocean – remote sensing of biological responses and their wider biogeochemical significance

    Directory of Open Access Journals (Sweden)

    Thomas J. Browning

    2015-03-01

    Full Text Available Transient micronutrient enrichment of the surface ocean can enhance phytoplankton growth rates and alter microbial community structure with an ensuing spectrum of biogeochemical feedbacks. Strong phytoplankton responses to micronutrients supplied by volcanic ash have been reported recently. Here we: (i synthesize findings from these recent studies; (ii report the results of a new remote sensing study of ash fertilization; and (iii calculate theoretical bounds of ash-fertilized carbon export. Our synthesis highlights that phytoplankton responses to ash do not always simply mimic that of iron amendment; the exact mechanisms for this are likely biogeochemically important but are not yet well understood. Inherent optical properties of ash-loaded seawater suggest rhyolitic ash biases routine satellite chlorophyll-a estimation upwards by more than an order of magnitude for waters with 0.5 mg chlorophyll-a m-3. For this reason post-ash-deposition chlorophyll-a changes in oligotrophic waters detected via standard Case 1 (open ocean algorithms should be interpreted with caution. Remote sensing analysis of historic events with a bias less than a factor of 2 provided limited stand-alone evidence for ash-fertilization. Confounding factors were poor coverage, incoherent ash dispersal, and ambiguity ascribing biomass changes to ash supply over other potential drivers. Using current estimates of iron release and carbon export efficiencies, uncertainty bounds of ash-fertilized carbon export for 3 events are presented. Patagonian iron supply to the Southern Ocean from volcanic eruptions is less than that of windblown dust on thousand year timescales but can dominate supply at shorter timescales. Reducing uncertainties in remote sensing of phytoplankton response and nutrient release from ash are avenues for enabling assessment of the oceanic response to large-scale transient nutrient enrichment.

  3. Intra-articular (IA) ropivacaine microparticle suspensions reduce pain, inflammation, cytokine, and substance p levels significantly more than oral or IA celecoxib in a rat model of arthritis.

    Science.gov (United States)

    Rabinow, Barrett; Werling, Jane; Bendele, Alison; Gass, Jerome; Bogseth, Roy; Balla, Kelly; Valaitis, Paul; Hutchcraft, Audrey; Graham, Sabine

    2015-02-01

    Current therapeutic treatment options for osteoarthritis entail significant safety concerns. A novel ropivacaine crystalline microsuspension for bolus intra-articular (IA) delivery was thus developed and studied in a peptidoglycan polysaccharide (PGPS)-induced ankle swelling rat model. Compared with celecoxib controls, both oral and IA, ropivacaine IA treatment resulted in a significant reduction of pain upon successive PGPS reactivation, as demonstrated in two different pain models, gait analysis and incapacitance testing. The reduction in pain was attended by a significant reduction in histological inflammation, which in turn was accompanied by significant reductions in the cytokines IL-18 and IL-1β. This may have been due to inhibition of substance P, which was also significantly reduced. Pharmacokinetic analysis indicated that the analgesic effects outlasted measurable ropivacaine levels in either blood or tissue. The results are discussed in the context of pharmacologic mechanisms both of local anesthetics as well as inflammatory arthritis.

  4. Reduced surface wave transmission function and neural networks for crack evaluation of concrete structures

    Science.gov (United States)

    Shin, Sung Woo; Yun, Chung Bang; Furuta, Hitoshi; Popovics, John S.

    2007-04-01

    Determination of crack depth in field using the self-calibrating surface wave transmission measurement and the cutting frequency in the transmission function (TRF) is very difficult due to variations of the measurement conditions. In this study, it is proposed to use the measured full TRF as a feature for crack depth assessment. A principal component analysis (PCA) is employed to generate a basis of the measured TRFs for various crack cases. The measured TRFs are represented by their projections onto the most significant principal components. Then artificial neural network (ANN) using the PCA-compressed TRFs is applied to assess the crack in concrete. Experimental study is carried out for five different crack cases to investigate the effectiveness of the proposed method. Results reveal that the proposed method can be effectively used for the crack depth assessment of concrete structures.

  5. Nitrogen cycling in the Southern Ocean Kerguelen Plateau area: evidence for significant surface nitrification from nitrate isotopic compositions

    Science.gov (United States)

    Dehairs, F.; Fripiat, F.; Cavagna, A.-J.; Trull, T. W.; Fernandez, C.; Davies, D.; Roukaerts, A.; Fonseca Batista, D.; Planchon, F.; Elskens, M.

    2015-03-01

    This paper presents whole water column data for nitrate N, O isotopic composition for the Kerguelen Plateau area and the basin extending east of Heard Island, aiming at understanding the N-cycling in this naturally iron fertilized area that is characterized by large re-current phytoplankton blooms. The KEOPS 2 expedition (October-November 2011) took place in spring season and complements knowledge gathered during an earlier summer expedition to the same area (KEOPS 1, February-March 2005). As noted by others a remarkable condition of the system is the moderate consumption of nitrate over the season (nitrate remains >20 μM) while silicic acid becomes depleted, suggesting significant recycling of nitrogen. Nitrate isotopic signatures in the upper water column do mimic this condition, with surprising overlap of spring and summer regressions of δ18ONO3 vs. δ15NNO3 isotopic compositions. These regressions obey rather closely the 18ϵ/15ϵ discrimination expected for nitrate uptake (18ϵ/15ϵ = 1), but regression slopes as large as 1.6 were observed for the mixed layer above the Kerguelen Plateau. A preliminarily mass balance calculation for the early bloom period points toward significant nitrification occurring in the mixed layer and which may be equivalent to up to 47% of nitrate uptake above the Kerguelen Plateau. A further finding concerns deep ocean low δ18ONO3 values (Polar Front Zone and which cannot be explained by remineralization and nitrification of the local particulate nitrogen flux, which is too small in magnitude. However, the studied area is characterized by a complex recirculation pattern that would keep deep waters in the area and could impose a seasonally integrated signature of surface water processes on the deep waters.

  6. Nitrogen cycling in the Southern Ocean Kerguelen Plateau area: evidence for significant surface nitrification from nitrate isotopic compositions

    Directory of Open Access Journals (Sweden)

    F. Dehairs

    2014-09-01

    Full Text Available This paper presents whole water column data for nitrate N, O isotopic composition for the Kerguelen Plateau area and the basin extending east of the island, aiming at understanding the N-cycling in this naturally iron fertilized area that is characterized by large re-current phytoplankton blooms. The KEOPS 2 expedition (October–November 2011 took place in spring season and complements knowledge gathered during an earlier summer expedition to the same area (KEOPS 1, February–March 2005. As noted by others a remarkable condition of the system is the moderate consumption of nitrate over the season (nitrate remains > 20 μM while silicic acid becomes depleted, suggesting significant recycling of nitrogen. Nitrate isotopic signatures in the upper water column do mimic this condition, with surprising overlap of spring and summer regressions of δ18ONO3 vs. δ15NNO3 isotopic compositions. These regressions obey rather closely the 18ϵ/15ϵ discrimination expected for nitrate uptake (18ϵ/15ϵ = 1, but regression slopes as large as 1.6 were observed for the mixed layer above the Kerguelen Plateau. A preliminary mass balance calculation for the early bloom period points toward significant nitrification occurring in the mixed layer and which could account for up to 80 % of nitrate uptake above the Kerguelen Plateau. A further finding concerns deep ocean low δ18ONO3 values (< 2‰ underlying high chlorophyll waters at the Polar Front Zone and which cannot be explained by remineralisation and nitrification of the local particulate nitrogen flux, which is too small in magnitude. However, the studied area is characterised by a complex recirculation pattern that would keep deep waters in the area and could impose a seasonally integrated signature of surface water processes on the deep waters.

  7. Expression of transforming growth factor-α and hepatitis B surface antigen in human hepatocellular carcinoma tissues and its significance

    Institute of Scientific and Technical Information of China (English)

    Jing Zhang; Wen-Liang Wang; Qing Li; Qing Qiao

    2004-01-01

    AIM: To evaluate the expression of transforming growth factor-alpha (TGF-α) and hepatitis B surface antigen (HBsAg) in human hepatocellular carcinoma (HCC) tissues and its significance. METHODS: Seventy specimens of HCC tissues were detected by immunohistochemical method. Five specimens of normal human liver tissues were used as control. RESULTS: The TGF-α positive expression rates in HCC and its surrounding tissues were 74.3%(52/70) and 88. t%(52/59), respectively. TGF-α positive granules were mainly in the cytoplasm and fewer existed on the karyotheca. The TGF-α positive expressing rate in well differentiated HCC was significantly higher than that in moderately and poorly differentiated HCC (P<0.05). The TGF-α positive expression also was observed in intrahepatic bile ducts (part of those were hyperplastic ducts). The HBsAg positive expression rates in HCC and its surrounding tissues were 21.4%(15/70) and 79.7%(47/59), respectively. HBsAg positive granules were in the cytoplasm, inclusion and on the karyotheca. There was a prominent positive correlation between TGF-α and HBsAg expression in HCC surrounding tissues (P<0.05, γ=0.34). TGF-α was usually existed with HBsAg in regenerated and/or dysplastic liver cells. In the five normal liver tissues, TGF-α and HBsAg were not detectable in hepatocytes and bile ducts.CONCLUSION: Hepatitis B virus infection is closely related with hepatocarcinogenesis. The overexpression of TGF-α in the liver seems to be associated with the regeneration of hepatocytes injured by HBsAg. The continued expression of TGF-α might lead to dysplasia of liver cells and development of HCC. Furthermore, TGF-α might play a role in morphogenesis and regeneration of intrahepatic bile ducts.

  8. Nano-objects as biomaterials: immense opportunities, significant challenges and the important use of surface analytical methods

    Energy Technology Data Exchange (ETDEWEB)

    Baer, Donald R.; Shutthanandan, Vaithiyalingam

    2017-05-30

    Nano-sized objects are increasingly important as biomaterials and their surfaces play critical roles in determining their beneficial or deleterious behaviors in biological systems. Important characteristics of nanomaterials that impact their application in many areas are described with a strong focus on the importance of particle surfaces and surface characterization. Understanding aspects of the inherent nature of nano-objects and the important role that surfaces play in these applications is a universal need for any research or product development using such materials in biological applications. The role of surface analysis methods in collecting critical information about the nature of particle surfaces and physicochemical properties of nano-objects is described along with the importance of including sample history and analysis results in a record of provenance information regarding specific batches of nano-objects.

  9. Laser surface modification of medical grade alloys for reduced heating in a magnetic resonance imaging environment

    Science.gov (United States)

    Benafan, O.; Chen, S.-Y.; Kar, A.; Vaidyanathan, R.

    2015-12-01

    Nanoscale surface modification of medical grade metallic alloys was conducted using a neodymium-doped yttrium aluminum garnet laser-based dopant diffusion technique. The objective of this approach was to minimize the induction heating by reducing the absorbed radio frequency field. Such an approach is advantageous in that the dopant is diffused into the alloy and is not susceptible to detachment or spallation as would an externally applied coating, and is expected to not deteriorate the mechanical and electrical properties of the base alloy or device. Experiments were conducted using a controlled environment laser system with the ability to control laser properties (i.e., laser power, spot size, and irradiation time) and dopant characteristics (i.e., temperature, concentration, and pressure). The reflective and transmissive properties of both the doped and untreated samples were measured in a radio frequency (63.86 MHz) magnetic field using a system comprising a high power signal generator, a localized magnetic field source and sensor, and a signal analyzer. The results indicate an increase in the reflectivity of the laser-treated samples compared to untreated samples. The effect of reflectivity on the heating of the alloys is investigated through a mathematical model incorporating Maxwell's equations and heat conduction.

  10. Laser surface modification of medical grade alloys for reduced heating in a magnetic resonance imaging environment

    Energy Technology Data Exchange (ETDEWEB)

    Benafan, O., E-mail: othmane.benafan@nasa.gov, E-mail: raj@ucf.edu; Vaidyanathan, R., E-mail: othmane.benafan@nasa.gov, E-mail: raj@ucf.edu [Advanced Materials Processing and Analysis Center (AMPAC), Materials Science and Engineering, Mechanical and Aerospace Engineering, University of Central Florida, Orlando, Florida 32816 (United States); Chen, S.-Y.; Kar, A. [Laser-Advanced Materials Processing Laboratory, Center for Research and Education in Optics and Lasers (CREOL), College of Optics and Photonics, University of Central Florida, Orlando, Florida 32816 (United States)

    2015-12-15

    Nanoscale surface modification of medical grade metallic alloys was conducted using a neodymium-doped yttrium aluminum garnet laser-based dopant diffusion technique. The objective of this approach was to minimize the induction heating by reducing the absorbed radio frequency field. Such an approach is advantageous in that the dopant is diffused into the alloy and is not susceptible to detachment or spallation as would an externally applied coating, and is expected to not deteriorate the mechanical and electrical properties of the base alloy or device. Experiments were conducted using a controlled environment laser system with the ability to control laser properties (i.e., laser power, spot size, and irradiation time) and dopant characteristics (i.e., temperature, concentration, and pressure). The reflective and transmissive properties of both the doped and untreated samples were measured in a radio frequency (63.86 MHz) magnetic field using a system comprising a high power signal generator, a localized magnetic field source and sensor, and a signal analyzer. The results indicate an increase in the reflectivity of the laser-treated samples compared to untreated samples. The effect of reflectivity on the heating of the alloys is investigated through a mathematical model incorporating Maxwell’s equations and heat conduction.

  11. Surface Plasmon Resonance (SPR Phenomenon of the Oxidizing and Reducing Polypyrrole

    Directory of Open Access Journals (Sweden)

    Nurlaila Rajabiah

    2016-12-01

    Full Text Available Surface Plasmon Resonance (SPR phenomenon of the oxidizing and reducing polypyrrole (PPy have been observed using a modified Au/PPy Kretschmann configuration. The observation was carried out through simulation Winspall 3.02 software and compared with some experimental data refractive index (n, absorbance index (, and thickness (τ reported in other literatures with spectroscopy ellipsometry. This simulation assumed that the SPR system use BK-7 halfcylinder prism (n= 1,515 and the laser beam was generated by HeNe (λ= 632,8 nm. The result showed that the optimum layer thickness of polypyrrole with neutral electrolyte solution in the reduction state is of about 20 nm. The polypyrrole with an acid solution in the oxidation state showed that the reflectivity curve is sharper and the width of the curve is smaller than the neutral electrolyte solution in the reduction state with the SPR angle of about 46,810 and the reflectivity value of about 0,217. Polypyrrole in a state of oxidation and reduction, related to the absorption, film thickness, and dielectric constant of materials, affected to the SPR angle shift and dip curve

  12. Waste Tyres as Heat Sink to Reduce the Driveway Surface Temperatures in Malaysia

    Directory of Open Access Journals (Sweden)

    Aniza Abdul Aziz

    2013-12-01

    Full Text Available The development of roads and driveways are on the rise as automobiles are now a necessity to all. This excessive development with its requirements increased the urban heat temperature and the generation of waste tyres. Waste tyre management has therefore been taken seriously by developed countries and since the European directive to ban used tyre products and whole tire disposal from landfill in 2003 and 2006 respectively, many researchers have looked for alternative ways to use the waste tyre. In Malaysia, The Smart and Cool Home Developer attempted to develop an eco-house by utilising waste tyre as the foundation for the driveway and claimed that the buried tyres act as a heat sink for the concrete and reduce the surface temperature of the driveway. Hence investigations were conducted on two sample houses to investigate this phenomenon. Findings from this pilot study show that waste tyres do act as a heat sink to the concrete driveways which affect the ambient temperature and relative humidity of the immediate surroundings.

  13. A process for SOI resonators with surface micromachined covers and reduced electrostatic gaps

    Science.gov (United States)

    Dekker, James R.; Alastalo, Ari; Kattelus, Hannu

    2010-04-01

    This paper describes work to fabricate resonators on silicon-on-insulator (SOI) wafers with sub-micron gaps and wafer level encapsulation. Non-aligned, high-temperature fusion bonding of a cover wafer over unreleased structures etched into a SOI wafer is followed by cover wafer stripping to reveal etched resonators beneath an oxide membrane. Reliable bonding is assured by bonding unreleased structures which can withstand the appropriate pre-bond cleaning operations. The bonded oxide membrane serves as the basis of a surface micromachined membrane which incorporates silicon nitride and a porous polysilicon layer to facilitate release and supercritical drying. The cavity pressure is estimated to be in the range of 1 Torr. Encapsulated resonators were also made using a gap reduction process. The process is based on sidewall oxidation of an etched sleeve to reduce the linewidth of the patterned electrostatic gaps by 200 nm before the deep trench etch. Encapsulated and electrically active devices with gaps down to 500 nm were obtained and etched through a 5 µm thick SOI device layer. SEM images showed that gaps of 300 nm could reach through the same thickness, though functional devices were not obtained. In addition, limitations on the anti-notching process limited its use during the trench etch and resulted in severe notch damage.

  14. MILD CHOLESTEROL DEPLETION REDUCES AMYLOID-β PRODUCTION BY IMPAIRING APP TRAFFICKING TO THE CELL SURFACE

    Science.gov (United States)

    Guardia-Laguarta, Cristina; Coma, Mireia; Pera, Marta; Clarimón, Jordi; Sereno, Lidia; Agulló, José M.; Molina-Porcel, Laura; Gallardo, Eduard; Deng, Amy; Berezovska, Oksana; Hyman, Bradley T.; Blesa, Rafael; Gómez-Isla, Teresa; Lleó, Alberto

    2009-01-01

    It has been suggested that cellular cholesterol levels can modulate the metabolism of the amyloid precursor protein (APP) but the underlying mechanism remains controversial. In the current study, we investigate in detail the relationship between cholesterol reduction, APP processing and γ-secretase function in cell culture studies. We found that mild membrane cholesterol reduction led to a decrease in Aβ40 and Aβ42 in different cell types. We did not detect changes in APP intracellular domain or Notch intracellular domain generation. Western blot analyses showed a cholesterol-dependent decrease in the APP C-terminal fragments and cell surface APP. Finally, we applied a fluorescence resonance energy transfer (FRET)-based technique to study APP-Presenilin 1 (PS1) interactions and lipid rafts in intact cells. Our data indicate that cholesterol depletion reduces association of APP into lipid rafts and disrupts APP-PS1 interaction. Taken together, our results suggest that mild membrane cholesterol reduction impacts the cleavage of APP upstream of γ-secretase and appears to be mediated by changes in APP trafficking and partitioning into lipid rafts. PMID:19457132

  15. Reducing Design Risk Using Robust Design Methods: A Dual Response Surface Approach

    Science.gov (United States)

    Unal, Resit; Yeniay, Ozgur; Lepsch, Roger A. (Technical Monitor)

    2003-01-01

    Space transportation system conceptual design is a multidisciplinary process containing considerable element of risk. Risk here is defined as the variability in the estimated (output) performance characteristic of interest resulting from the uncertainties in the values of several disciplinary design and/or operational parameters. Uncertainties from one discipline (and/or subsystem) may propagate to another, through linking parameters and the final system output may have a significant accumulation of risk. This variability can result in significant deviations from the expected performance. Therefore, an estimate of variability (which is called design risk in this study) together with the expected performance characteristic value (e.g. mean empty weight) is necessary for multidisciplinary optimization for a robust design. Robust design in this study is defined as a solution that minimizes variability subject to a constraint on mean performance characteristics. Even though multidisciplinary design optimization has gained wide attention and applications, the treatment of uncertainties to quantify and analyze design risk has received little attention. This research effort explores the dual response surface approach to quantify variability (risk) in critical performance characteristics (such as weight) during conceptual design.

  16. Surface Charges and Shell Crosslinks Each Play Significant Roles in Mediating Degradation, Biofouling, Cytotoxicity and Immunotoxicity for Polyphosphoester-based Nanoparticles

    Science.gov (United States)

    Elsabahy, Mahmoud; Zhang, Shiyi; Zhang, Fuwu; Deng, Zhou J.; Lim, Young H.; Wang, Hai; Parsamian, Perouza; Hammond, Paula T.; Wooley, Karen L.

    2013-11-01

    The construction of nanostructures from biodegradable precursors and shell/core crosslinking have been pursued as strategies to solve the problems of toxicity and limited stability, respectively. Polyphosphoester (PPE)-based micelles and crosslinked nanoparticles with non-ionic, anionic, cationic, and zwitterionic surface characteristics for potential packaging and delivery of therapeutic and diagnostic agents, were constructed using a quick and efficient synthetic strategy, and importantly, demonstrated remarkable differences in terms of cytotoxicity, immunotoxicity, and biofouling properties, as a function of their surface characteristics and also with dependence on crosslinking throughout the shell layers. For instance, crosslinking of zwitterionic micelles significantly reduced the immunotoxicity, as evidenced from the absence of secretions of any of the 23 measured cytokines from RAW 264.7 mouse macrophages treated with the nanoparticles. The micelles and their crosslinked analogs demonstrated lower cytotoxicity than several commercially-available vehicles, and their degradation products were not cytotoxic to cells at the range of the tested concentrations. PPE-nanoparticles are expected to have broad implications in clinical nanomedicine as alternative vehicles to those involved in several of the currently available medications.

  17. Short communication: Evaluation of a sol-gel-based stainless steel surface modification to reduce fouling and biofilm formation during pasteurization of milk.

    Science.gov (United States)

    Liu, Dylan Zhe; Jindal, Shivali; Amamcharla, Jayendra; Anand, Sanjeev; Metzger, Lloyd

    2017-04-01

    Milk fouling and biofilms are common problems in the dairy industry across many types of processing equipment. One way to reduce milk fouling and biofilms is to modify the characteristics of milk contact surfaces. This study examines the viability of using Thermolon (Porcelain Industries Inc., Dickson, TN), a sol-gel-based surface modification of stainless steel, during thermal processing of milk. We used stainless steel 316L (control) and sol-gel-modified coupons in this study to evaluate fouling behavior and bacterial adhesion. The surface roughness as measured by an optical profiler indicated that the control coupons had a slightly smoother finish. Contact angle measurements showed that the modified surface led to a higher water contact angle, suggesting a more hydrophobic surface. The modified surface also had a lower surface energy (32.4 ± 1.4 mN/m) than the control surface (41.36 ± 2.7 mN/m). We evaluated the susceptibility of control and modified stainless steel coupons to fouling in a benchtop plate heat exchanger. We observed a significant reduction in the amount of fouled layer on modified surfaces. We found an average fouling weight of 19.21 mg/cm(2) and 0.37 mg/cm(2) on the control and modified stainless steel coupons, respectively. We also examined the adhesion of Bacillus and biofilm formation, and observed that the modified stainless steel surface offered greater resistance to biofilm formation. Overall, the Thermolon-modified surface showed potential in the thermal processing of milk, offering significantly lower fouling and bacterial attachment than the control surface.

  18. Simulation and preparation of surface EVA in reduced gravity at the Marseilles Bay subsea analogue sites

    Science.gov (United States)

    Weiss, P.; Gardette, B.; Chirié, B.; Collina-Girard, J.; Delauze, H. G.

    2012-12-01

    Extravehicular activity (EVA) of astronauts during space missions is simulated nowadays underwater in neutral buoyancy facilities. Certain aspects of weightlessness can be reproduced underwater by adding buoyancy to a diver-astronaut, therefore exposing the subject to the difficulties of working without gravity. Such tests were done at the COMEX' test pool in Marseilles in the 1980s to train for a French-Russian mission to the MIR station, for the development of the European HERMES shuttle and the COLUMBUS laboratory. However, space agencies are currently studying missions to other destinations than the International Space Station in orbit, such as the return to the Moon, NEO (near-Earth objects) or Mars. All these objects expose different gravities: Moon has one sixth of Earth's gravity, Mars has a third of Earth's gravity and asteroids have virtually no surface gravity; the astronaut "floats" above the ground. The preparation of such missions calls for a new concept in neutral buoyancy training, not on man-made structures, but on natural terrain, underwater, to simulate EVA operations such as sampling, locomotion or even anchoring in low gravity. Underwater sites can be used not only to simulate the reduced gravity that astronauts will experience during their field trips, also human factors like stress are more realistically reproduced in such environment. The Bay of Marseille hosts several underwater sites that can be used to simulate various geologic morphologies, such as sink-holes which can be used to simulate astronaut descends into craters, caves where explorations of lava tubes can be trained or monolithic rock structures that can be used to test anchoring devices (e.g., near Earth objects). Marseilles with its aerospace and maritime/offshore heritage hosts the necessary logistics and expertise that is needed to perform such simulations underwater in a safe manner (training of astronaut-divers in local test pools, research vessels, subsea robots and

  19. Zinc-ion implanted and deposited titanium surfaces reduce adhesion of Streptococccus mutans

    Energy Technology Data Exchange (ETDEWEB)

    Xu Juan, E-mail: doctorxue@126.com [Implant Center, School of Stomatology Jilin University, Changchun, Jilin (China) and Stomatological Hospital, Urumqi, Xinjiang (China); Ding Gang [Department of Stomatology, Yidu Central Hospital, Weifang, Shandong (China); Capital Medical University School of Stomatology, Beijing (China); Li Jinlu; Yang Shenhui; Fang Bisong [Capital Medical University School of Stomatology, Beijing (China); Sun Hongchen, E-mail: hcsun@jlu.edu.cn [Implant Center, School of Stomatology Jilin University, Changchun, Jilin (China); Zhou Yanmin, E-mail: zhouym62@126.com [Implant Center, School of Stomatology Jilin University, Changchun, Jilin (China)

    2010-10-01

    While titanium (Ti) is a commonly used dental implant material with advantageous biocompatible and mechanical properties, native Ti surfaces do not have the ability to prevent bacterial colonization. The objective of this study was to evaluate the chemical composition and bacterial adhesive properties of zinc (Zn) ion implanted and deposited Ti surfaces (Zn-PIIID-Ti) as potential dental implant materials. Surfaces of pure Ti (cp-Ti) were modified with increasing concentrations of Zn using plasma immersion ion implantation and deposition (PIIID), and elemental surface compositions were characterized by X-ray photoelectron spectrometry (XPS). To evaluate bacterial responses, Streptococcus mutans were seeded onto the modifiedTi surfaces for 48 h and subsequently observed by scanning electron microscopy. Relative numbers of bacteria on each surface were assessed by collecting the adhered bacteria, reculturing and counting colony forming units after 48 h on bacterial grade plates. Ti, oxygen and carbon elements were detected on all surfaces by XPS. Increased Zn signals were detected on Zn-PIIID-Ti surfaces, correlating with an increase of Zn-deposition time. Substantial numbers of S. mutans adhered to cp-Ti samples, whereas bacterial adhesion on Zn-PIIID-Ti surfaces signficantly decreased as the Zn concentration increased (p < 0.01). In conclusion, PIIID can successfully introduce Zn onto a Ti surface, forming a modified surface layer bearing Zn ions that consequently deter adhesion of S. mutans, a common bacterium in the oral environment.

  20. A cold and fresh ocean surface in the Nordic Seas during MIS 11: Significance for the future ocean

    Science.gov (United States)

    Kandiano, Evgenia S.; Meer, Marcel T. J.; Bauch, Henning A.; Helmke, Jan; Damsté, Jaap S. Sinninghe; Schouten, Stefan

    2016-10-01

    Paleoceanographical studies of Marine Isotope Stage (MIS) 11 have revealed higher-than-present sea surface temperatures (SSTs) in the North Atlantic and in parts of the Arctic but lower-than-present SSTs in the Nordic Seas, the main throughflow area of warm water into the Arctic Ocean. We resolve this contradiction by complementing SST data based on planktic foraminiferal abundances with surface salinity changes using hydrogen isotopic compositions of alkenones in a core from the central Nordic Seas. The data indicate the prevalence of a relatively cold, low-salinity, surface water layer in the Nordic Seas during most of MIS 11. In spite of the low-density surface layer, which was kept buoyant by continuous melting of surrounding glaciers, warmer Atlantic water was still propagating northward at the subsurface thus maintaining meridional overturning circulation. This study can help to better constrain the impact of continuous melting of Greenland and Arctic ice on high-latitude ocean circulation and climate.

  1. Surface Drainage and Mulching Drip-Irrigated Tomatoes Reduces Soil Salinity and Improves Fruit Yield

    Science.gov (United States)

    Hou, Maomao; Zhu, Lvdan; Jin, Qiu

    2016-01-01

    A study on the effects of mulched drip irrigation combined with surface drainage on saline soil and tomatoes was conducted in coastal areas of eastern China, where the crops are subjected to excessive salt. The treatments contained three irrigation rates—200, 250 and 300 m3/ha—and three drain ditch depths—10, 20 and 30 cm. The contents of soil salinity, organic matter and available nutrient were observed, and the tomato plant height, stem diameter and leaf area index during different growth periods were recorded. Results showed that the total removal rate of salt from soil at a 0–1 m depth was 8.7–13.2% for the three drainages. Compared with the control, the treatments increased the content of available N (by 12.1–47.1%) and available K (by 5.0–21.9%) in the soils inside the mulch and decreased the content of available N (by 3.4–22.1%) and available K (by 7.5–16.4%) in the soils outside the mulch. For tomatoes, the plant height and the stem diameter was increased significantly by the irrigations but was not significantly affected by the drainages, and the leaf area index was increased by 0.39~1.76, 1.10~2.90 and 2.80~6.86 respectively in corresponding to the seedling, flowering and fruit-set stage. Moreover, yield-increase rates of 7.9–27.6% were found for the treatments compared to the control with a similar amount of applied water. PMID:27153110

  2. Macrophytes may not contribute significantly to removal of nutrients, pharmaceuticals, and antibiotic resistance in model surface constructed wetlands.

    Science.gov (United States)

    Cardinal, Pascal; Anderson, Julie C; Carlson, Jules C; Low, Jennifer E; Challis, Jonathan K; Beattie, Sarah A; Bartel, Caitlin N; Elliott, Ashley D; Montero, Oscar F; Lokesh, Sheetal; Favreau, Alex; Kozlova, Tatiana A; Knapp, Charles W; Hanson, Mark L; Wong, Charles S

    2014-06-01

    Outdoor shallow wetland mesocosms, designed to simulate surface constructed wetlands to improve lagoon wastewater treatment, were used to assess the role of macrophytes in the dissipation of wastewater nutrients, selected pharmaceuticals, and antibiotic resistance genes (ARGs). Specifically, mesocosms were established with or without populations of Typha spp. (cattails), Myriophyllum sibiricum (northern water milfoil), and Utricularia vulgaris (bladderwort). Following macrophyte establishment, mesocosms were seeded with ARG-bearing organisms from a local wastewater lagoon, and treated with a single pulse of artificial municipal wastewater with or without carbamazepine, clofibric acid, fluoxetine, and naproxen (each at 7.6μg/L), as well as sulfamethoxazole and sulfapyridine (each at 150μg/L). Rates of pharmaceutical dissipation over 28d ranged from 0.073 to 3.0d(-1), corresponding to half-lives of 0.23 to 9.4d. Based on calculated rate constants, observed dissipation rates were consistent with photodegradation driving clofibric acid, naproxen, sulfamethoxazole, and sulfapyridine removal, and with sorption also contributing to carbamazepine and fluoxetine loss. Of the seven gene determinants assayed, only two genes for both beta-lactam resistance (blaCTX and blaTEM) and sulfonamide resistance (sulI and sulII) were found in sufficient quantity for monitoring. Genes disappeared relatively rapidly from the water column, with half-lives ranging from 2.1 to 99d. In contrast, detected gene levels did not change in the sediment, with the exception of sulI, which increased after 28d in pharmaceutical-treated systems. These shallow wetland mesocosms were able to dissipate wastewater contaminants rapidly. However, no significant enhancement in removal of nutrients or pharmaceuticals was observed in mesocosms with extensive aquatic plant communities. This was likely due to three factors: first, use of naïve systems with an unchallenged capacity for nutrient assimilation and

  3. [Reducing centers on the surface of Escherichia coli bacteria and their role in copper-induced plasma membrane permeability].

    Science.gov (United States)

    Lebedev, V S; Veselovskiĭ, A V; Deĭnega, E Iu; Fedorov, Iu I

    2000-01-01

    The reducing properties of Escherichia coli and their role in the induction of nonselective cationic permeability of plasma membrane by the action of Cu2+ ions were studied. The ability of cells to reduce exogenous dithiopyridine was shown to be maximal in freshly collected culture and to decrease upon starvation or exhaustion of bacteria by dinitrophenol, in the presence of other oxidants of cell thiols in the medium, and after the disturbance of the barrier properties of membrane by tetrachloracetic acid or butanol. The alkylation of cell thiols accessible for N-ethyl maleimide completely disrupted the reducing activity of bacteria. These data are consistent with the conception that the reduction of dithiopyridine and Cu2+ ions by bacteria occurs on the thiol-containing centers of the cell surface, which are continuously reduced by the transfer of cell reducing equivalents from the inner to the outer surface of plasma membrane. The analysis of data on the effect of external oxidizing and reducing agents on the copper-induced plasmolysis of bacteria showed that the induction of membrane permeability by the action of copper can occur upon interaction with critical targets on the surface of Cu+ ions formed in the periplasmic space in the reaction of Cu2+ ions with reducing centers.

  4. Investigations on reducing microbiologically-influenced corrosion of aluminum by using super-hydrophobic surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Liu Tao, E-mail: liutao@shmtu.edu.c [Institute of Marine Materials Science and Engineering, Shanghai Maritime University, Shanghai 201306 (China); Dong Lihua; Liu Tong; Yin Yansheng [Institute of Marine Materials Science and Engineering, Shanghai Maritime University, Shanghai 201306 (China)

    2010-07-15

    Electrochemical impedance spectroscopy, potentiodynamic polarization and scanning electron microscopy were carried out to determine the effect of super-hydrophobic surfaces on the marine bacterium Vibrio natriegens (V. natriegens) adhesion. Four different samples were prepared in order to investigate the anti-biocorrosion mechanism of super-hydrophobic surfaces. Potentiodynamic polarization suggested that the V. natriegens attached on the surface mainly enhanced the reaction kinetics of the anodic reaction and accelerated the dissolution of aluminum. EIS results were interpreted with different equivalent circuits to model the physicoelectric characteristics of the electrode/biofilm/solution interface. The results showed that neither anodization nor chemical modification could decrease the bacterial adhesion and corrosion rate individually. V. natriegens showed only weak attachment to the super-hydrophobic surface, and the biocorrosion mechanism was closely associated with surface energy and surface topography.

  5. CD28⁻ CD8⁺ T cells are significantly reduced and correlate with disease duration in juveniles with type 1 diabetes.

    Science.gov (United States)

    Yarde, Danielle N; Lorenzo-Arteaga, Kristina; Corley, Kevin P; Cabrera, Monina; Sarvetnick, Nora E

    2014-10-01

    Type 1 diabetes (T1D) is a chronic disease caused by autoimmune destruction of insulin-producing pancreatic β-cells. T1D is typically diagnosed in children, but information regarding immune cell subsets in juveniles with T1D is scarce. Therefore, we studied various lymphocytic populations found in the peripheral blood of juveniles with T1D compared to age-matched controls (ages 2-17). One population of interest is the CD28(-) CD8(+) T cell subset, which are late-differentiated cells also described as suppressors. These cells are altered in a number of disease states and have been shown to be reduced in adults with T1D. We found that the proportion of CD28(-) cells within the CD8(+) T cell population is significantly reduced in juvenile type 1 diabetics. Furthermore, this reduction is not correlated with age in T1D juveniles, although a significant negative correlation between proportion CD28(-) CD8(+) T cells and age was observed in the healthy controls. Finally, correlation analysis revealed a significant and negative correlation between the proportion of CD28(-) CD8(+) T cells and T1D disease duration. These findings show that the CD28(-) CD8(+) T cell population is perturbed following onset of disease and may prove to be a valuable marker for monitoring the progression of T1D.

  6. Boiling heat transfer to LN2 and LH2 - Influence of surface orientation and reduced body forces

    Science.gov (United States)

    Merte, H., Jr.; Oker, E.; Littles, J. W.

    1973-01-01

    The quantitative determination of the influence of heater surface orientation and gravity on nucleate pool boiling of liquid nitrogen and liquid hydrogen is described. A transient calorimeter technique, well suited for obtaining pool boiling data under reduced gravity and used earlier by Clark and Merte (1963), was employed after being adapted to flat a surface whose orientation could be varied. The obtained determination results are reviewed.

  7. Zinc-ion implanted and deposited titanium surfaces reduce adhesion of Streptococccus mutans

    Science.gov (United States)

    Xu, Juan; Ding, Gang; Li, Jinlu; Yang, Shenhui; Fang, Bisong; Sun, Hongchen; Zhou, Yanmin

    2010-10-01

    While titanium (Ti) is a commonly used dental implant material with advantageous biocompatible and mechanical properties, native Ti surfaces do not have the ability to prevent bacterial colonization. The objective of this study was to evaluate the chemical composition and bacterial adhesive properties of zinc (Zn) ion implanted and deposited Ti surfaces (Zn-PIIID-Ti) as potential dental implant materials. Surfaces of pure Ti (cp-Ti) were modified with increasing concentrations of Zn using plasma immersion ion implantation and deposition (PIIID), and elemental surface compositions were characterized by X-ray photoelectron spectrometry (XPS). To evaluate bacterial responses, Streptococcus mutans were seeded onto the modifiedTi surfaces for 48 h and subsequently observed by scanning electron microscopy. Relative numbers of bacteria on each surface were assessed by collecting the adhered bacteria, reculturing and counting colony forming units after 48 h on bacterial grade plates. Ti, oxygen and carbon elements were detected on all surfaces by XPS. Increased Zn signals were detected on Zn-PIIID-Ti surfaces, correlating with an increase of Zn-deposition time. Substantial numbers of S. mutans adhered to cp-Ti samples, whereas bacterial adhesion on Zn-PIIID-Ti surfaces signficantly decreased as the Zn concentration increased ( p S. mutans, a common bacterium in the oral environment.

  8. Improving winter leaf area index estimation in coniferous forests and its significance in estimating the land surface albedo

    Science.gov (United States)

    Wang, Rong; Chen, Jing M.; Pavlic, Goran; Arain, Altaf

    2016-09-01

    Winter leaf area index (LAI) of evergreen coniferous forests exerts strong control on the interception of snow, snowmelt and energy balance. Simulation of winter LAI and associated winter processes in land surface models is challenging. Retrieving winter LAI from remote sensing data is difficult due to cloud contamination, poor illumination, lower solar elevation and higher radiation reflection by snow background. Underestimated winter LAI in evergreen coniferous forests is one of the major issues limiting the application of current remote sensing LAI products. It has not been fully addressed in past studies in the literature. In this study, we used needle lifespan to correct winter LAI in a remote sensing product developed by the University of Toronto. For the validation purpose, the corrected winter LAI was then used to calculate land surface albedo at five FLUXNET coniferous forests in Canada. The RMSE and bias values for estimated albedo were 0.05 and 0.011, respectively, for all sites. The albedo map over coniferous forests across Canada produced with corrected winter LAI showed much better agreement with the GLASS (Global LAnd Surface Satellites) albedo product than the one produced with uncorrected winter LAI. The results revealed that the corrected winter LAI yielded much greater accuracy in simulating land surface albedo, making the new LAI product an improvement over the original one. Our study will help to increase the usability of remote sensing LAI products in land surface energy budget modeling.

  9. Charge transfer and formation of reduced Ce{sup 3+} upon adsorption of metal atoms at the ceria (110) surface

    Energy Technology Data Exchange (ETDEWEB)

    Nolan, Michael [Tyndall National Institute, University College Cork, Lee Maltings, Prospect Row, Cork (Ireland)

    2012-04-07

    The modification of cerium dioxide with nanoscale metal clusters is intensely researched for catalysis applications, with gold, silver, and copper having been particularly well studied. The interaction of the metal cluster with ceria is driven principally by a localised interaction between a small number of metal atoms (as small as one) and the surface and understanding the fundamentals of the interaction of metal atoms with ceria surfaces is therefore of great interest. Much attention has been focused on the interaction of metals with the (111) surface of ceria, since this is the most stable surface and can be grown as films, which are probed experimentally. However, nanostructures exposing other surfaces such as (110) show high activity for reactions including CO oxidation and require further study; these nanostructures could be modified by deposition of metal atoms or small clusters, but there is no information to date on the atomic level details of metal-ceria interactions involving the (110) surface. This paper presents the results of density functional theory (DFT) corrected for on-site Coulomb interactions (DFT+U) calculations of the adsorption of a number of different metal atoms at an extended ceria (110) surface; the metals are Au, Ag, Cu, Al, Ga, In, La, Ce, V, Cr, and Fe. Upon adsorption all metals are oxidised, transferring electron(s) to the surface, resulting in localised surface distortions. The precise details depend on the identity of the metal atom. Au, Ag, Cu each transfer one electron to the surface, reducing one Ce ion to Ce{sup 3+}, while of the trivalent metals, Al and La are fully oxidised, but Ga and In are only partially oxidised. Ce and the transition metals are also partially oxidised, with the number of reduced Ce ions possible in this surface no more than three per adsorbed metal atom. The predicted oxidation states of the adsorbed metal atoms should be testable in experiments on ceria nanostructures modified with metal atoms.

  10. Surface Microtextures of Slipping Zone Soil of Some Landslides in the Three Gorges Reservoir District and Their Significance

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The mineral assemblage and content and surface microtextures of slipping zone soil of several landslides in the Three Gorges Reservoir District have been analyzed using the scanning electron microscope (SEM) and X-ray diffractometer (XRD). All the mineral assemblages are similar in these landslides. The main minerals are montmorillonite, illite, kaolinite, chlorite, quartz and feldspar. There are two kinds of surface microtexture in the slipping zone soil, i.e., linear scratches and arcuate scratches. Based on analyses of the changes of the microtextures, one can obtain information about the number, directions and stages of landslide movements. The authors have also studied the mechanism of landslide formation, evaluated the stability of landslides and revival possibility of ancient landslides and forecasted the activity of similar landslides in different districts. The surface microtexture features of stable landslides and mobile landslides are summarized and it is concluded that the existence of filamentous bacteria may result in or increase movements of landslides.

  11. Obstacles, an Energy-Efficient Method to Reduce Downdraught from Large Glazed Surfaces

    DEFF Research Database (Denmark)

    Topp, Claus; Heiselberg, Per

    Thermal discomfort due to downdraught from glazed surfaces are often met by convectors placed close to the surface, but this may lead to increased energy consumption. The objective of this research is to investigate the effect of a horizontal obstacle on the boundary layer flow at a high cold ver...

  12. Inactivation of baculovirus by isoflavonoids on chickpea (Cicer arietinum) leaf surfaces reduces the efficacy of nucleopolyhedrovirus against Helicoverpa armigera

    OpenAIRE

    Stevenson, Philip C.; D'Cunha, Reju F.; Grzywacz, David

    2010-01-01

    Biological pesticides based on nucleopolyhedroviruses (NPVs) can provide an effective and environmentally benign alternative to synthetic chemicals. On some crops, however, the efficacy and persistence of NPVs is known to be reduced by plant specific factors. The present study investigated the efficacy of Helicoverpa armigera NPV (HearNPV) for control of H. armigera larvae, and showed that chickpea reduced the infectivity of virus occlusion bodies (OBs) exposed to the leaf surface of chickpea...

  13. Gridded 5-day mean sea surface height anomaly and significant wave height from Jason-1 and OSTM/Jason-2 satellites (NODC Accession 0065055)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This accession contains the gridded 5-day mean sea surface height anomaly (SSHA) and Ku Band significant wave height (SWH-KU) observed from Jason-1 and OSTM/Jason-2...

  14. The design of superhydrophobic stainless steel surfaces by controlling nanostructures: A key parameter to reduce the implantation of pathogenic bacteria.

    Science.gov (United States)

    Bruzaud, Jérôme; Tarrade, Jeanne; Celia, Elena; Darmanin, Thierry; Taffin de Givenchy, Elisabeth; Guittard, Frédéric; Herry, Jean-Marie; Guilbaud, Morgan; Bellon-Fontaine, Marie-Noëlle

    2017-04-01

    Reducing bacterial adhesion on substrates is fundamental for various industries. In this work, new superhydrophobic surfaces are created by electrodeposition of hydrophobic polymers (PEDOT-F4 or PEDOT-H8) on stainless steel with controlled topographical features, especially at a nano-scale. Results show that anti-bioadhesive and anti-biofilm properties require the control of the surface topographical features, and should be associated with a low adhesion of water onto the surface (Cassie-Baxter state) with limited crevice features at the scale of bacterial cells (nano-scale structures).

  15. A cold and fresh ocean surface in the Nordic Seas during MIS 11: Significance for the future ocean

    NARCIS (Netherlands)

    Kandiano, E.S.; Van der Meer, M.T.J.; Bauch, H.A.; Helmke, J.; Sinninghe Damsté, J.S.; Schouten, S.

    2016-01-01

    Paleoceanographical studies of Marine Isotope Stage (MIS) 11 have revealed higher-than-presentsea surface temperatures (SSTs) in the North Atlantic and in parts of the Arctic but lower-than-present SSTsin the Nordic Seas, the main throughflow area of warm water into the Arctic Ocean. We resolve this

  16. A cold and fresh ocean surface in the Nordic Seas during MIS 11 : Significance for the future ocean

    NARCIS (Netherlands)

    Kandiano, Evgenia S.; van der Meer, M.T.J.; Bauch, H.A.; Helmke, Jan; Sinninghe Damsté, J.S.; Schouten, S.

    2016-01-01

    Paleoceanographical studies of Marine Isotope Stage (MIS) 11 have revealed higher-than-present sea surface temperatures (SSTs) in the North Atlantic and in parts of the Arctic but lower-than-present SSTs in the Nordic Seas, the main throughflow area of warm water into the Arctic Ocean. We resolve th

  17. Surface functionalization of bioactive glasses with natural molecules of biological significance, part II: Grafting of polyphenols extracted from grape skin

    Science.gov (United States)

    Zhang, Xin; Ferraris, Sara; Prenesti, Enrico; Verné, Enrica

    2013-12-01

    Polyphenols, as one of the most important family of phytochemicals protective substances from grape fruit, possess various biological activities and health-promoting benefits, for example: inhibition of some degenerative diseases, cardiovascular diseases and certain types of cancers, reduction of plasma oxidative stress and slowing aging. The combination of polyphenols and biomaterials may have good potential to reach good bioavailability and controlled release, as well as to give biological signaling properties to the biomaterial surfaces. In this research, conventional solvent extraction was developed for obtaining polyphenols from dry grape skins. The Folin&Ciocalteu method was used to determine the amount of total polyphenols in the extracts. Surface functionalization of two bioactive glasses (SCNA and CEL2) was performed by grafting the extracted polyphenols on their surfaces. The effectiveness of the functionalization was tested by UV spectroscopy, which analyzes the amount of polyphenols in the uptake solution (before and after functionalization) and on solid samples, and XPS, which analyzes the presence of phenols on the material surface.

  18. GIS based 3D visualization of subsurface and surface lineaments / faults and their geological significance, northern tamil nadu, India

    Science.gov (United States)

    Saravanavel, J.; Ramasamy, S. M.

    2014-11-01

    The study area falls in the southern part of the Indian Peninsular comprising hard crystalline rocks of Archaeozoic and Proterozoic Era. In the present study, the GIS based 3D visualizations of gravity, magnetic, resistivity and topographic datasets were made and therefrom the basement lineaments, shallow subsurface lineaments and surface lineaments/faults were interpreted. These lineaments were classified as category-1 i.e. exclusively surface lineaments, category-2 i.e. surface lineaments having connectivity with shallow subsurface lineaments and category-3 i.e. surface lineaments having connectivity with shallow subsurface lineaments and basement lineaments. These three classified lineaments were analyzed in conjunction with known mineral occurrences and historical seismicity of the study area in GIS environment. The study revealed that the category-3 NNE-SSW to NE-SW lineaments have greater control over the mineral occurrences and the N-S, NNE-SSW and NE-SW, faults/lineaments control the seismicities in the study area.

  19. Segmentation process significantly influences the accuracy of 3D surface models derived from cone beam computed tomography

    NARCIS (Netherlands)

    Fourie, Zacharias; Damstra, Janalt; Schepers, Rutger H; Gerrits, Pieter; Ren, Yijin

    2012-01-01

    AIMS: To assess the accuracy of surface models derived from 3D cone beam computed tomography (CBCT) with two different segmentation protocols. MATERIALS AND METHODS: Seven fresh-frozen cadaver heads were used. There was no conflict of interests in this study. CBCT scans were made of the heads and 3D

  20. The Activating NKG2C Receptor Is Significantly Reduced in NK Cells after Allogeneic Stem Cell Transplantation in Patients with Severe Graft-versus-Host Disease

    Directory of Open Access Journals (Sweden)

    Lambros Kordelas

    2016-10-01

    Full Text Available Natural killer (NK cells play a central role in the innate immune system. In allogeneic stem cell transplantation (alloSCT, alloreactive NK cells derived by the graft are discussed to mediate the elimination of leukemic cells and dendritic cells in the patient and thereby to reduce the risk for leukemic relapses and graft-versus-host reactions. The alloreactivity of NK cells is determined by various receptors including the activating CD94/NKG2C and the inhibitory CD94/NKG2A receptors, which both recognize the non-classical human leukocyte antigen E (HLA-E. Here we analyze the contribution of these receptors to NK cell alloreactivity in 26 patients over the course of the first year after alloSCT due to acute myeloid leukemia, myelodysplastic syndrome and T cell Non-Hodgkin-Lymphoma. Our results show that NK cells expressing the activating CD94/NKG2C receptor are significantly reduced in patients after alloSCT with severe acute and chronic graft-versus-host disease (GvHD. Moreover, the ratio of CD94/NKG2C to CD94/NKG2A was reduced in patients with severe acute and chronic GvHD after receiving an HLA-mismatched graft. Collectively, these results provide evidence for the first time that CD94/NKG2C is involved in GvHD prevention.

  1. The Activating NKG2C Receptor Is Significantly Reduced in NK Cells after Allogeneic Stem Cell Transplantation in Patients with Severe Graft-versus-Host Disease

    Science.gov (United States)

    Kordelas, Lambros; Steckel, Nina-Kristin; Horn, Peter A.; Beelen, Dietrich W.; Rebmann, Vera

    2016-01-01

    Natural killer (NK) cells play a central role in the innate immune system. In allogeneic stem cell transplantation (alloSCT), alloreactive NK cells derived by the graft are discussed to mediate the elimination of leukemic cells and dendritic cells in the patient and thereby to reduce the risk for leukemic relapses and graft-versus-host reactions. The alloreactivity of NK cells is determined by various receptors including the activating CD94/NKG2C and the inhibitory CD94/NKG2A receptors, which both recognize the non-classical human leukocyte antigen E (HLA-E). Here we analyze the contribution of these receptors to NK cell alloreactivity in 26 patients over the course of the first year after alloSCT due to acute myeloid leukemia, myelodysplastic syndrome and T cell Non-Hodgkin-Lymphoma. Our results show that NK cells expressing the activating CD94/NKG2C receptor are significantly reduced in patients after alloSCT with severe acute and chronic graft-versus-host disease (GvHD). Moreover, the ratio of CD94/NKG2C to CD94/NKG2A was reduced in patients with severe acute and chronic GvHD after receiving an HLA-mismatched graft. Collectively, these results provide evidence for the first time that CD94/NKG2C is involved in GvHD prevention. PMID:27801784

  2. The determination of surface charge on nitrogen-containing reduced graphene oxides and its application to adsorb molybdate

    Energy Technology Data Exchange (ETDEWEB)

    Li, Mingjie, E-mail: limingjie19870210@163.com [Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190 (China); School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Beijing 100190 (China); Research Centre for Process Pollution Control, Beijing 100190 (China); National Engineering Research Center of Distillation Technology, Tianjin University, Tianjin 300072 (China); Liu, Chenming, E-mail: chmliu@ipe.ac.cn [Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190 (China); National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Beijing 100190 (China); Research Centre for Process Pollution Control, Beijing 100190 (China); Cao, Hongbin, E-mail: hbcao@ipe.ac.cn [Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190 (China); National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Beijing 100190 (China); Research Centre for Process Pollution Control, Beijing 100190 (China); Pan, Jiachuan, E-mail: jpan0618@gmail.com [Syracuse University, Syracuse, NY 13244 (United States); Zhao, He, E-mail: hzhao@ipe.ac.cn [Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190 (China); National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Beijing 100190 (China); Research Centre for Process Pollution Control, Beijing 100190 (China); and others

    2015-02-15

    To speculate the performance of chemically reduced graphene oxide from different reductants, detailed investigation of chemical structures needs diverse characterizations. Surface charge, mainly resulting from surface functional groups, may provide a facile method to comprehensively predict performance on certain levels. Surface charge of hydrazine-reduced graphene oxide (HrGO) and p-phenylenediamine (p-PDA)-reduced graphene oxide (ArGO) was investigated by cyclic voltammetry. The charge generation mechanism was further analysed by X-ray photoelectron spectroscopy. Electrical impedance spectroscopy was applied to investigate the effect of surface charge on the adsorptive properties. Furthermore, the experiments on MoO{sub 4}{sup 2−} adsorbed by ArGO were carried out at different pH values. Results indicate that the surface charge on ArGO was more positive than that on HrGO, which is mainly due to protonation of amino group. MoO{sub 4}{sup 2−} adsorption experiments indicate that relative positive charge made ArGO more efficient than HrGO to adsorb MoO{sub 4}{sup 2−}. - Highlights: • The p-PDA reduced graphene oxide (ArGO) has positive charge on its surface. • Positive surface charge on ArGO is mainly from the protonation of amine groups. • Positive charge enhances the diffusion and adsorption of negative ions onto ArGO. • The maximum MoO{sub 4}{sup 2−} adsorption capacity of ArGO can reach to 61 mg g{sup −1}.

  3. Numerical simulation of power consumption under the effect of reduced surface area of the DS furnace

    Science.gov (United States)

    Kesavan, V.; Srinivasan, M.; Ramasamy, P.

    2017-05-01

    Numerical simulation is used as an effective tool in development and optimization of the multi-crystalline silicon growth by the directional solidification. A transient global heat transfer model was used to investigate the effect of reduced hot zone on the power consumption, thermal field and melt-crystal interface during the solidification process. The results show that reduced hot zone design is more effective with suitable thermal gradient, interface shape and reduced power consumption.

  4. Systemically administered interleukin-10 reduces tumor necrosis factor-alpha production and significantly improves functional recovery following traumatic spinal cord injury in rats.

    Science.gov (United States)

    Bethea, J R; Nagashima, H; Acosta, M C; Briceno, C; Gomez, F; Marcillo, A E; Loor, K; Green, J; Dietrich, W D

    1999-10-01

    In these studies, we examined the neuroprotective effects of the potent antiinflammatory cytokine interleukin-10 (IL-10) following spinal cord injury (SCI). Neuroprotection was assessed by using behavioral and morphological end points. We hypothesized that injury-induced inflammation contributes to the resulting neuropathology and subsequent loss of function. Therefore, by attenuating injury-induced inflammation, we should promote functional recovery. The New York University device was used to induce moderate SCI and study the resulting inflammatory response and functional consequences of inhibiting this response in rats. We determined that SCI induces the expression of tumor necrosis factor-alpha (TNF-alpha) in the spinal cord and by SCI-activated monocytes isolated from the peripheral circulation. IL-10 (5.0 microg) administered 30 minutes after-injury significantly reduced the expression of TNF-alpha protein in the spinal cord and in vitro by SCI-activated monocytes. Next, we investigated whether IL-10 would improve functional recovery after SCI. Randomized, double-blinded studies demonstrated that a single injection of IL-10 significantly improves hind limb motor function 2 months after injury, as determined by the Basso, Beattie and Bresnahan (BBB) open-field behavioral test. IL-10-treated animals had a mean BBB score of 18.0+/-0.5 (SEM, n = 9) compared with a score of 12.9+/-0.6 (SEM, n = 9) for the saline-treated controls. Morphological analysis demonstrated that IL-10 reduces lesion volume by approximately 49% 2 months after injury. These data suggest that acute administration of IL-10 reduces TNF-alpha synthesis in the spinal cord and by activated macrophages, is neuroprotective, and promotes functional recovery following SCI.

  5. Surface photovoltage spectroscopy study of reduced and oxidized nanocrystalline TiO 2 films

    Science.gov (United States)

    Rothschild, A.; Levakov, A.; Shapira, Y.; Ashkenasy, N.; Komem, Y.

    2003-06-01

    Nanocrystalline TiO 2 films used for gas sensors have been studied by means of surface photovoltage spectroscopy and other analytical tools to investigate the oxygen chemisorption effect on the electrical properties of the films. The results show that the surface (and intergranular interface) band bending increases with oxygen exposure due to electron trapping at midgap states induced by chemisorption. The surface electronic structure is revealed by the measurements, allowing determination of the sensing mechanism of these important films. In addition, a photoinduced chemisorption of oxygen at room temperature is observed. This has important implications for low-temperature gas sensors.

  6. Ultrahigh Aspect Ratio Copper-Nanowire-Based Hybrid Transparent Conductive Electrodes with PEDOT:PSS and Reduced Graphene Oxide Exhibiting Reduced Surface Roughness and Improved Stability.

    Science.gov (United States)

    Zhu, Zhaozhao; Mankowski, Trent; Balakrishnan, Kaushik; Shikoh, Ali Sehpar; Touati, Farid; Benammar, Mohieddine A; Mansuripur, Masud; Falco, Charles M

    2015-08-05

    Copper nanowires (CuNWs) with ultrahigh aspect ratio are synthesized with a solution process and spray-coated onto select substrates to fabricate transparent conductive electrodes (TCEs). Different annealing methods are investigated and compared for effectiveness and convenience. The CuNWs are subsequently combined with the conductive polymer poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate) ( PSS) or with reduced graphene oxide (rGO) platelets in order to reduce the surface roughness and improve the durability of the fabricated TCEs. Our best-performing PSS/CuNW films have optical transmittance T550 = 84.2% (at λ = 550 nm) and sheet resistance Rs = 25 Ω/sq, while our best CuNW/rGO films have T550 = 84% and Rs = 21.7 Ω/sq.

  7. The chemical digestion of Ti6Al7Nb scaffolds produced by Selective Laser Melting reduces significantly ability of Pseudomonas aeruginosa to form biofilm.

    Science.gov (United States)

    Junka, Adam F; Szymczyk, Patrycja; Secewicz, Anna; Pawlak, Andrzej; Smutnicka, Danuta; Ziółkowski, Grzegorz; Bartoszewicz, Marzenna; Chlebus, Edward

    2016-01-01

    In our previous work we reported the impact of hydrofluoric and nitric acid used for chemical polishing of Ti-6Al-7Nb scaffolds on decrease of the number of Staphylococcus aureus biofilm forming cells. Herein, we tested impact of the aforementioned substances on biofilm of Gram-negative microorganism, Pseudomonas aeruginosa, dangerous pathogen responsible for plethora of implant-related infections. The Ti-6Al-7Nb scaffolds were manufactured using Selective Laser Melting method. Scaffolds were subjected to chemical polishing using a mixture of nitric acid and fluoride or left intact (control group). Pseudomonal biofilm was allowed to form on scaffolds for 24 hours and was removed by mechanical vortex shaking. The number of pseudomonal cells was estimated by means of quantitative culture and Scanning Electron Microscopy. The presence of nitric acid and fluoride on scaffold surfaces was assessed by means of IR and rentgen spetorscopy. Quantitative data were analysed using the Mann-Whitney test (P ≤ 0.05). Our results indicate that application of chemical polishing correlates with significant drop of biofilm-forming pseudomonal cells on the manufactured Ti-6Al-7Nb scaffolds ( p = 0.0133, Mann-Whitney test) compared to the number of biofilm-forming cells on non-polished scaffolds. As X-ray photoelectron spectroscopy revealed the presence of fluoride and nitrogen on the surface of scaffold, we speculate that drop of biofilm forming cells may be caused by biofilm-supressing activity of these two elements.

  8. Fact Sheets: Final Rules to Reduce Toxic Air Pollutants from Surface Coating of Metal Cans

    Science.gov (United States)

    This page contains the August 2003 final rule fact sheet and the December 2005 final rule fact sheet that contain information on the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Surface Coating of Metal Cans.

  9. Surface analysis, hydrogen adsorption and electrochemical performance of alkali-reduce treated hydrogen storage alloy

    Institute of Scientific and Technical Information of China (English)

    陈卫祥; 徐铸德; 涂江平; 李海洋; 陈石; 袁俊; 鲍世宁

    2002-01-01

    The hydrogen storage alloy powders (MlNi4.0Co0.6Al0.4, Ml=rich-La mischmetal) were treated in a hot 6mol/L KOH+0.02mol/L KBH4 solution, the surface compositions and chemical states of the treated and untreated alloys were analyzed by XPS and EDX, the hydrogen adsorption on the surface of these alloys was evaluated by thermal desorption spectroscopy (TDS), the effects of the surface treatment on the electrochemical performances of the alloy electrodes were investigated. The results show that the hydrogen adsorption is greatly strengthened by the surface modification, and hence leads to marked improvement in the electrocatalytic activity, the treated alloy exhibits higher exchange current density and lower apparent activation energy for the hydrogen electrode reaction than the untreated alloy.

  10. Surface functionalization of bioactive glasses with natural molecules of biological significance, Part I: Gallic acid as model molecule

    Science.gov (United States)

    Zhang, Xin; Ferraris, Sara; Prenesti, Enrico; Verné, Enrica

    2013-12-01

    Gallic acid (3,4,5-trihydroxybenzoic acid, GA) and its derivatives are a group of biomolecules (polyphenols) obtained from plants. They have effects which are potentially beneficial to heath, for example they are antioxidant, anticarcinogenic and antibacterial, as recently investigated in many fields such as medicine, food and plant sciences. The main drawbacks of these molecules are both low stability and bioavailability. In this research work the opportunity to graft GA to bioactive glasses is investigated, in order to deliver the undamaged biological molecule into the body, using the biomaterial surfaces as a localized carrier. GA was considered for functionalization since it is a good model molecule for polyphenols and presents several interesting biological activities, like antibacterial, antioxidant and anticarcinogenic properties. Two different silica based bioactive glasses (SCNA and CEL2), with different reactivity, were employed as substrates. UV photometry combined with the Folin&Ciocalteu reagent was adopted to test the concentration of GA in uptake solution after functionalization. This test verified how much GA consumption occurred with surface modification and it was also used on solid samples to test the presence of GA on functionalized glasses. XPS and SEM-EDS techniques were employed to characterize the modification of material surface properties and functional group composition before and after functionalization.

  11. A functional variant in the cystathionine β-synthase gene promoter significantly reduces congenital heart disease susceptibility in a Han Chinese population

    Institute of Scientific and Technical Information of China (English)

    Jian-Yuan Zhao; Xue-Yan Yang; Kai-Hu Shi; Shu-Na Sun; Jia Hou; Zhi-Zhou Ye; Jue Wang

    2013-01-01

    Homocysteine is an independent risk factor for various cardiovascular diseases.There are two ways to remove homocysteine from embryonic cardiac cells:remethylation to form methionine or transsulfuration to form cysteine.Cystathionine β-synthase (CBS) catalyzes the first step of homocysteine transsulfuration as a rate-limiting enzyme.In this study,we identified a functional variant-4673C>G (rs2850144) in the CBS gene promoter region that significantly reduces the susceptibility to congenital heart disease (CHD) in a Han Chinese population consisting of 2 340 CHD patients and 2 270 controls.Individuals carrying the heterozygous CG and homozygous GG genotypes had a 15% (odds ratio (OR) =0.85,95% confidence interval (CI) =0.75-0.96,P =0.011) and 40% (OR =0.60,95% CI =0.49-0.73,P =1.78 × 10-7) reduced risk to develop CHD than the wild-type CC genotype carriers in the combined samples,respectively.Additional stratified analyses demonstrated that CBS-4673C>G is significantly related to septation defects and conotruncal defects.In vivo detection of CBS mRNA levels in human cardiac tissues and in vitro luciferase assays consistently showed that the minor G allele significantly increased CBS transcription.A functional analysis revealed that both the attenuated transcription suppressor SP1 binding affinity and the CBS promoter hypomethylation specifically linked with the minor G allele contributed to the remarkably upregulated CBS expression.Consequently,the carriers with genetically increased CBS expression would benefit from the protection due to the low homocysteine levels maintained by CBS in certain cells during the critical heart development stages.These results shed light on unexpected role of CBS and highlight the importance of homocysteine removal in cardiac development.

  12. Combined steam and ultrasound treatment of broilers at slaughter: a promising intervention to significantly reduce numbers of naturally occurring campylobacters on carcasses.

    Science.gov (United States)

    Musavian, Hanieh S; Krebs, Niels H; Nonboe, Ulf; Corry, Janet E L; Purnell, Graham

    2014-04-17

    Steam or hot water decontamination treatment of broiler carcasses is hampered by process limitations due to prolonged treatment times and adverse changes to the epidermis. In this study, a combination of steam with ultrasound (SonoSteam®) was investigated on naturally contaminated broilers that were processed at conventional slaughter speeds of 8,500 birds per hour in a Danish broiler plant. Industrial-scale SonoSteam equipment was installed in the evisceration room, before the inside/outside carcass washer. The SonoSteam treatment was evaluated in two separate trials performed on two different dates. Numbers of naturally occurring Campylobacter spp. and TVC were determined from paired samples of skin excised from opposite sides of the breast of the same carcass, before and after treatments. Sampling was performed at two different points on the line: i) before and after the SonoSteam treatment and ii) before the SonoSteam treatment and after 80 min of air chilling. A total of 44 carcasses were examined in the two trials. Results from the first trial showed that the mean initial Campylobacter contamination level of 2.35 log₁₀ CFU was significantly reduced (n=12, psignificant reduction (n=11, psignificant reductions (n=10, pSignificant reductions (n=11, pnumbers analyzed before the SonoSteam treatment (2.02 log₁₀ CFU) and after the air chilling treatment (1.37 log₁₀ CFU). The effect of air chilling without SonoSteam treatment was determined using 12 carcasses pre- and postchill. Results showed insignificant reductions of 0.09 log₁₀ from a mean initial level of 2.19 log₁₀ CFU. Numbers of TVC before treatments ranged between 3.47 and 4.79 log₁₀ CFU. In all cases, TVC was significantly (psignificantly reduce numbers of Campylobacter on naturally contaminated broilers.

  13. Parthenolide reduces empty lacunae and osteoclastic bone surface resorption induced by polyethylene particles in a murine calvarial model of peri-implant osteolysis.

    Science.gov (United States)

    Zawawi, Muhamad S F; Marino, Victor; Perilli, Egon; Cantley, Melissa D; Xu, Jiake; Purdue, P Edward; Dharmapatni, Anak A S S K; Haynes, David R; Crotti, Tania N

    2015-11-01

    The study aimed to determine the effects of parthenolide (PAR) on bone volume (BV) and bone surface resorption as assessed by live-animal microcomputed tomography (μCT) and possible osteocyte death as indicated by empty lacunae histologically in polyethylene (PE) particle-induced calvarial osteolysis in mice. Baseline μCT scans were conducted 7 days preimplantation of 2 × 10(8) PE particles/mL over the calvariae (day 0). PAR at 1 mg/kg/day was subcutaneously injected on days 0, 4, 7, and 10. At day 14, BV and surface resorption was analyzed with μCT. Calvarial tissue was processed for histomorphometric osteocyte evaluation. Serum was analyzed for type-1 carboxy-terminal collagen crosslinks (CTX-1) and osteoclast associated receptor (OSCAR) levels by ELISA. PE significantly decreased BV (p = 0.0368), increased surface bone resorption area (p = 0.0022), and increased the percentage of empty lacunae (p = 0.0043). Interestingly, PAR significantly reduced the resorption surface area (p = 0.0022) and the percentage of empty osteocyte lacunae (p = 0.0087) in the PE-calvariae, but it did not affect BV, serum CTX-1 or OSCAR levels. The ability of PAR to inhibit PE-induced surface bone erosion may better reflect the in vivo situation, where bone resorption occurs on the surface at the bone-implant interface and may also be related to the role of osteocytes in this pathology.

  14. Moderate Weight Reduction in an Outpatient Obesity Intervention Program Significantly Reduces Insulin Resistance and Risk Factors for Cardiovascular Disease in Severely Obese Adolescents

    Directory of Open Access Journals (Sweden)

    J. Grulich-Henn

    2011-01-01

    Full Text Available Background. Metabolic risk factors like insulin resistance and dyslipidemia are frequently observed in severly obese children. We investigated the hypothesis that moderate weight reduction by a low-threshold intervention is already able to reduce insulin resistance and cardiovascular risk factors in severely obese children. Methods. A group of 58 severely obese children and adolescents between 8 and 17 years participating in a six-month-long outpatient program was studied before and after treatment. The program included behavioral treatment, dietary education and specific physical training. Metabolic parameters were measured in the fasting state, insulin resistance was evaluated in an oral glucose tolerance test. Results. Mean standard deviation score of the body mass index (SDS-BMI in the study group dropped significantly from +2.5 ± 0.5 to 2.3 ± 0.6 (P<0.0001 after participation in the program. A significant decrease was observed in HOMA (6.3 ± 4.2 versus 4.9 ± 2.4, P<0.03, and in peak insulin levels (232.7 ± 132.4 versus 179.2 ± 73.3 μU/mL, P<0.006. Significant reductions were also observed in mean levels of hemoglobin A1c, total cholesterol and LDL cholesterol. Conclusions. These data demonstrate that already moderate weight reduction is able to decrease insulin resistance and dyslipidemia in severely obese children and adolescents.

  15. Reduced platelet adhesion on the surface of polyurethane bearing structure of sulfobetaine.

    Science.gov (United States)

    Yuan, J; Zhang, J; Zhu, J; Shen, J; Lin, S C; Zhu, W; Fang, J L

    2003-10-01

    Poly(etherurethane)s are widely used as blood-contacting biomaterials due to their good biocompatibility and mechanical properties. Nevertheless, their blood compatibility is still not adequate for the more demanding applications. Surface modification is an effective way to improve the blood compatibility and retain the bulk properties of biomaterials. The purpose of present study was to design and synthesize a novel nonthrombogenic biomaterial by modifying the surface of poly(etherurethane) with zwitterionic monomer. Films of polyurethane were grafted with sulfobetaine by a three-step procedure. In the first step, the film surfaces were treated with hexamethylene diisocyanate (HDI) in toluene at 50 degrees C in the presence of di-n-butyl tin dilaurate (DBTDL) as a catalyst. The extent of the reaction was measured by ATR-IR spectra; a maximum number of free NCO group was obtained after a reaction time of 90 min. In the second step, the hydroxyl group of 4-dimethylamino-1-butanol (DMAB) was allowed to react in toluene with isocyanate groups bound on the surface. In the third step, sulfobetaine was formed on the surface through the ring-opening reaction between tertiary amine of DMAB and 1,3- propane-sultone (PS). It was characterized by ATR-IR, XPS. The data showed that the grafted surfaces were composed of sulfobetaine. The results of the contact angle measurements showed that they were strongly hydrophilic. The state of platelet adhesion and shape variation for the attached platelets was described. The modified surface shows excellent blood compatibility feature by the low platelet adhesion.

  16. Concave Pit-Containing Scaffold Surfaces Improve Stem Cell-Derived Osteoblast Performance and Lead to Significant Bone Tissue Formation

    Science.gov (United States)

    Cusella-De Angelis, Maria Gabriella; Laino, Gregorio; Piattelli, Adriano; Pacifici, Maurizio; De Rosa, Alfredo; Papaccio, Gianpaolo

    2007-01-01

    Background Scaffold surface features are thought to be important regulators of stem cell performance and endurance in tissue engineering applications, but details about these fundamental aspects of stem cell biology remain largely unclear. Methodology and Findings In the present study, smooth clinical-grade lactide-coglyolic acid 85:15 (PLGA) scaffolds were carved as membranes and treated with NMP (N-metil-pyrrolidone) to create controlled subtractive pits or microcavities. Scanning electron and confocal microscopy revealed that the NMP-treated membranes contained: (i) large microcavities of 80–120 µm in diameter and 40–100 µm in depth, which we termed primary; and (ii) smaller microcavities of 10–20 µm in diameter and 3–10 µm in depth located within the primary cavities, which we termed secondary. We asked whether a microcavity-rich scaffold had distinct bone-forming capabilities compared to a smooth one. To do so, mesenchymal stem cells derived from human dental pulp were seeded onto the two types of scaffold and monitored over time for cytoarchitectural characteristics, differentiation status and production of important factors, including bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF). We found that the microcavity-rich scaffold enhanced cell adhesion: the cells created intimate contact with secondary microcavities and were polarized. These cytological responses were not seen with the smooth-surface scaffold. Moreover, cells on the microcavity-rich scaffold released larger amounts of BMP-2 and VEGF into the culture medium and expressed higher alkaline phosphatase activity. When this type of scaffold was transplanted into rats, superior bone formation was elicited compared to cells seeded on the smooth scaffold. Conclusion In conclusion, surface microcavities appear to support a more vigorous osteogenic response of stem cells and should be used in the design of therapeutic substrates to improve bone repair and

  17. Clay mineral distribution in surface sediments of the South China Sea and its significance for in sediment sources and transport

    Institute of Scientific and Technical Information of China (English)

    刘建国; 陈木宏; 陈忠; 颜文

    2010-01-01

    Clay minerals of surface sediments in the South China Sea (SCS) are analyzed with X-ray diffraction, and their transport is explored with a grain size trend analysis (GSTA) model. Results show that clay mineral types in various sedimentary environments have different sediment sources and transport routes. Sediments in the northern SCS (north of 20°N) between the southwest of Taiwan Island and the outer mouth of the Pearl River have high contents of illite and chlorite, which are derived mainly from sediment...

  18. Hypoxis hemerocallidea Significantly Reduced Hyperglycaemia and Hyperglycaemic-Induced Oxidative Stress in the Liver and Kidney Tissues of Streptozotocin-Induced Diabetic Male Wistar Rats

    Directory of Open Access Journals (Sweden)

    Oluwafemi O. Oguntibeju

    2016-01-01

    Full Text Available Background. Hypoxis hemerocallidea is a native plant that grows in the Southern African regions and is well known for its beneficial medicinal effects in the treatment of diabetes, cancer, and high blood pressure. Aim. This study evaluated the effects of Hypoxis hemerocallidea on oxidative stress biomarkers, hepatic injury, and other selected biomarkers in the liver and kidneys of healthy nondiabetic and streptozotocin- (STZ- induced diabetic male Wistar rats. Materials and Methods. Rats were injected intraperitoneally with 50 mg/kg of STZ to induce diabetes. The plant extract-Hypoxis hemerocallidea (200 mg/kg or 800 mg/kg aqueous solution was administered (daily orally for 6 weeks. Antioxidant activities were analysed using a Multiskan Spectrum plate reader while other serum biomarkers were measured using the RANDOX chemistry analyser. Results. Both dosages (200 mg/kg and 800 mg/kg of Hypoxis hemerocallidea significantly reduced the blood glucose levels in STZ-induced diabetic groups. Activities of liver enzymes were increased in the diabetic control and in the diabetic group treated with 800 mg/kg, whereas the 200 mg/kg dosage ameliorated hepatic injury. In the hepatic tissue, the oxygen radical absorbance capacity (ORAC, ferric reducing antioxidant power (FRAP, catalase, and total glutathione were reduced in the diabetic control group. However treatment with both doses improved the antioxidant status. The FRAP and the catalase activities in the kidney were elevated in the STZ-induced diabetic group treated with 800 mg/kg of the extract possibly due to compensatory responses. Conclusion. Hypoxis hemerocallidea demonstrated antihyperglycemic and antioxidant effects especially in the liver tissue.

  19. Immunization of teenagers with a fifth dose of reduced DTaP-IPV induces high levels of pertussis antibodies with a significant increase in opsonophagocytic activity.

    Science.gov (United States)

    Aase, Audun; Herstad, Tove Karin; Merino, Samuel; Bolstad, Merete; Sandbu, Synne; Bakke, Hilde; Aaberge, Ingeborg S

    2011-08-01

    Waning vaccine-induced immunity against Bordetella pertussis is observed among adolescents and adults. A high incidence of pertussis has been reported in this population, which serves as a reservoir for B. pertussis. A fifth dose of reduced antigen of diphtheria-tetanus-acellular-pertussis and inactivated polio vaccine was given as a booster dose to healthy teenagers. The antibody activity against B. pertussis antigens was measured prior to and 4 to 8 weeks after the booster by different assays: enzyme-linked immunosorbent assays (ELISAs) of IgG and IgA against pertussis toxin (PT) and filamentous hemagglutinin (FHA), IgG against pertactin (PRN), opsonophagocytic activity (OPA), and IgG binding to live B. pertussis. There was a significant increase in the IgG activity against PT, FHA, and PRN following the booster immunization (P antibodies against FHA and PRN contribute the most to the OPA and IgG binding.

  20. Relative significance of microtopography and vegetation as controls on surface water flow on a low-gradient floodplain

    Science.gov (United States)

    Choi, Jungyill; Harvey, Judson W.

    2014-01-01

    Surface water flow controls water velocities, water depths, and residence times, and influences sediment and nutrient transport and other ecological processes in shallow aquatic systems. Flow through wetlands is substantially influenced by drag on vegetation stems but is also affected by microtopography. Our goal was to use microtopography data directly in a widely used wetland model while retaining the advantages of the model’s one-dimensional structure. The base simulation with no explicit treatment of microtopography only performed well for a period of high water when vegetation dominated flow resistance. Extended simulations using microtopography can improve the fit to low-water conditions substantially. The best fit simulation had a flow conductance parameter that decreased in value by 70 % during dry season such that mcrotopographic features blocked 40 % of the cross sectional width for flow. Modeled surface water became ponded and flow ceased when 85 % of the cross sectional width became blocked by microtopographic features. We conclude that vegetation drag dominates wetland flow resistance at higher water levels and microtopography dominates at low water levels with the threshold delineated by the top of microtopographic features. Our results support the practicality of predicting flow on floodplains using relatively easily measured physical and biological variables.

  1. Significance of frost action and surface soil characteristics to wind erosion at Rocky Flats, Colorado. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Caine, N.

    1978-09-01

    This study of the potential links between soil freezing and wind erosion was conducted at Rocky Flats during 4 winters. Most of the study has involved the conditions leading to the growth of segregation ice in the surface soil and the ground heave which that produces. This occurs about 15 times in the average winter at Rocky Flats, always on a diurnal cycle. Such frost action is preferentially distributed in time and space and cannot be estimated from air temperatures alone. November and March are the months of most frequent frost heave, and then only in the days following precipitation or snowmelt. The most marked frost effects are found on exposed interfluve and hillcrest situations, where there are patches of bare soil. Almost no effects are found on the valley floors. Soil disturbance by segregation ice leads to a marked decrease in soil bulk density, and presumably in soil strength though this change has not been quantitatively defined. However, this does not lead to wind erosion of the soil at the study site because that surface is more influenced by the vegetation cover than by the soil characteristics.

  2. Anhydride-functional silane immobilized onto titanium surfaces induces osteoblast cell differentiation and reduces bacterial adhesion and biofilm formation

    Energy Technology Data Exchange (ETDEWEB)

    Godoy-Gallardo, Maria, E-mail: maria.godoy.gallardo@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); Guillem-Marti, Jordi, E-mail: jordi.guillem.marti@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); Sevilla, Pablo, E-mail: psevilla@euss.es [Department of Mechanics, Escola Universitària Salesiana de Sarrià (EUSS), C/ Passeig de Sant Bosco, 42, 08017 Barcelona (Spain); Manero, José M., E-mail: jose.maria.manero@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); Gil, Francisco J., E-mail: francesc.xavier.gil@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); and others

    2016-02-01

    Bacterial infection in dental implants along with osseointegration failure usually leads to loss of the device. Bioactive molecules with antibacterial properties can be attached to titanium surfaces with anchoring molecules such as silanes, preventing biofilm formation and improving osseointegration. Properties of silanes as molecular binders have been thoroughly studied, but research on the biological effects of these coatings is scarce. The aim of the present study was to determine the in vitro cell response and antibacterial effects of triethoxysilypropyl succinic anhydride (TESPSA) silane anchored on titanium surfaces. X-ray photoelectron spectroscopy confirmed a successful silanization. The silanized surfaces showed no cytotoxic effects. Gene expression analyses of Sarcoma Osteogenic (SaOS-2) osteoblast-like cells cultured on TESPSA silanized surfaces reported a remarkable increase of biochemical markers related to induction of osteoblastic cell differentiation. A manifest decrease of bacterial adhesion and biofilm formation at early stages was observed on treated substrates, while favoring cell adhesion and spreading in bacteria–cell co-cultures. Surfaces treated with TESPSA could enhance a biological sealing on implant surfaces against bacteria colonization of underlying tissues. Furthermore, it can be an effective anchoring platform of biomolecules on titanium surfaces with improved osteoblastic differentiation and antibacterial properties. - Highlights: • TESPSA silane induces osteoblast differentiation. • TESPSA reduces bacterial adhesion and biofilm formation. • TESPSA is a promising anchoring platform of biomolecules onto titanium.

  3. SRC Inhibition Reduces NR2B Surface Expression and Synaptic Plasticity in the Amygdala

    Science.gov (United States)

    Sinai, Laleh; Duffy, Steven; Roder, John C.

    2010-01-01

    The Src protein tyrosine kinase plays a central role in the regulation of N-methyl-d-aspartate receptor (NMDAR) activity by regulating NMDAR subunit 2B (NR2B) surface expression. In the amygdala, NMDA-dependent synaptic plasticity resulting from convergent somatosensory and auditory inputs contributes to emotional memory; however, the role of Src…

  4. Cortical surface-based analysis reduces bias and variance in kinetic modeling of brain PET data

    DEFF Research Database (Denmark)

    Greve, Douglas N; Svarer, Claus; Fisher, Patrick M

    2014-01-01

    intersubject variance than when volume smoothing was used. This translates into more than 4 times fewer subjects needed in a group analysis to achieve similarly powered statistical tests. Surface-based smoothing has less bias and variance because it respects cortical geometry by smoothing the PET data only...

  5. Synthesis and characterization of a lubricin mimic (mLub) to reduce friction and adhesion on the articular cartilage surface.

    Science.gov (United States)

    Lawrence, Alexandra; Xu, Xin; Bible, Melissa D; Calve, Sarah; Neu, Corey P; Panitch, Alyssa

    2015-12-01

    The lubricating proteoglycan, lubricin, facilitates the remarkable low friction and wear properties of articular cartilage in the synovial joints of the body. Lubricin lines the joint surfaces and plays a protective role as a boundary lubricant in sliding contact; decreased expression of lubricin is associated with cartilage degradation and the pathogenesis of osteoarthritis. An unmet need for early osteoarthritis treatment is the development of therapeutic molecules that mimic lubricin function and yet are also resistant to enzymatic degradation common in the damaged joint. Here, we engineered a lubricin mimic (mLub) that is less susceptible to enzymatic degradation and binds to the articular surface to reduce friction. mLub was synthesized using a chondroitin sulfate backbone with type II collagen and hyaluronic acid (HA) binding peptides to promote interaction with the articular surface and synovial fluid constituents. In vitro and in vivo characterization confirmed the binding ability of mLub to isolated type II collagen and HA, and to the cartilage surface. Following trypsin treatment to the cartilage surface, application of mLub, in combination with purified or commercially available hyaluronan, reduced the coefficient of friction, and adhesion, to control levels as assessed over macro-to micro-scales by rheometry and atomic force microscopy. In vivo studies demonstrate an mLub residency time of less than 1 week. Enhanced lubrication by mLub reduces surface friction and adhesion, which may suppress the progression of degradation and cartilage loss in the joint. mLub therefore shows potential for treatment in early osteoarthritis following injury.

  6. Application of bacteriophages to reduce biofilms formed by hydrogen sulfide producing bacteria on surfaces in a rendering plant.

    Science.gov (United States)

    Gong, Chao; Jiang, Xiuping

    2015-08-01

    Hydrogen sulfide producing bacteria (SPB) in raw animal by-products are likely to grow and form biofilms in the rendering processing environments, resulting in the release of harmful hydrogen sulfide (H2S) gas. The objective of this study was to reduce SPB biofilms formed on different surfaces typically found in rendering plants by applying a bacteriophage cocktail. Using a 96-well microplate method, we determined that 3 SPB strains of Citrobacter freundii and Hafnia alvei are strong biofilm formers. Application of 9 bacteriophages (10(7) PFU/mL) from families of Siphoviridae and Myoviridae resulted in a 33%-70% reduction of biofilm formation by each SPB strain. On stainless steel and plastic templates, phage treatment (10(8) PFU/mL) reduced the attached cells of a mixed SPB culture (no biofilm) by 2.3 and 2.7 log CFU/cm(2) within 6 h at 30 °C, respectively, as compared with 2 and 1.5 log CFU/cm(2) reductions of SPB biofilms within 6 h at 30 °C. Phage treatment was also applied to indigenous SPB biofilms formed on the environmental surface, stainless steel, high-density polyethylene plastic, and rubber templates in a rendering plant. With phage treatment (10(9) PFU/mL), SPB biofilms were reduced by 0.7-1.4, 0.3-0.6, and 0.2-0.6 log CFU/cm(2) in spring, summer, and fall trials, respectively. Our study demonstrated that bacteriophages could effectively reduce the selected SPB strains either attached to or in formed biofilms on various surfaces and could to some extent reduce the indigenous SPB biofilms on the surfaces in the rendering environment.

  7. Deferasirox reduces iron overload significantly in nontransfusion-dependent thalassemia: 1-year results from a prospective, randomized, double-blind, placebo-controlled study.

    Science.gov (United States)

    Taher, Ali T; Porter, John; Viprakasit, Vip; Kattamis, Antonis; Chuncharunee, Suporn; Sutcharitchan, Pranee; Siritanaratkul, Noppadol; Galanello, Renzo; Karakas, Zeynep; Lawniczek, Tomasz; Ros, Jacqueline; Zhang, Yiyun; Habr, Dany; Cappellini, Maria Domenica

    2012-08-02

    Nontransfusion-dependent thalassemia (NTDT) patients may develop iron overload and its associated complications despite receiving only occasional or no transfusions. The present 1-year, randomized, double-blind, placebo-controlled THALASSA (Assessment of Exjade in Nontransfusion-Dependent Thalassemia) trial assessed the efficacy and safety of deferasirox in iron-overloaded NTDT patients. A total of 166 patients were randomized in a 2:1:2:1 ratio to starting doses of 5 or 10 mg/kg/d of deferasirox or placebo. The means ± SD of the actual deferasirox doses received over the duration of the study in the 5 and 10 mg/kg/d starting dose cohorts were 5.7 ± 1.4 and 11.5 ± 2.9 mg/kg/d, respectively. At 1 year, the liver iron concentration (LIC) decreased significantly compared with placebo (least-squares mean [LSM] ± SEM, -2.33 ± 0.7 mg Fe/g dry weight [dw], P = .001, and -4.18 ± 0.69 mg Fe/g dw, P deferasirox groups, respectively (baseline values [means ± SD], 13.11 ± 7.29 and 14.56 ± 7.92 mg Fe/g dw, respectively). Similarly, serum ferritin decreased significantly compared with placebo by LSM -235 and -337 ng/mL for the deferasirox 5 and 10 mg/kg/d groups, respectively (P deferasirox significantly reduces iron overload in NTDT patients with a frequency of overall adverse events similar to placebo.

  8. Glycophospholipid Formulation with NADH and CoQ10 Significantly Reduces Intractable Fatigue in Western Blot-Positive ‘Chronic Lyme Disease’ Patients: Preliminary Report

    Directory of Open Access Journals (Sweden)

    Garth L. Nicolson

    2012-03-01

    Full Text Available Background: An open label 8-week preliminary study was conducted in a small number of patients to determine if a combination oral supplement containing a mixture of phosphoglycolipids, coenzyme Q10 and microencapsulated NADH and other nutrients could affect fatigue levels in long-term, Western blot-positive, multi-symptom ‘chronic Lyme disease’ patients (also called ‘post-treatment Lyme disease’ or ‘post Lyme syndrome’ with intractable fatigue. Methods: The subjects in this study were 6 males (mean age = 45.1 ± 12.4 years and 10 females (mean age = 54.6 ± 7.4 years with ‘chronic Lyme disease’ (determined by multiple symptoms and positive Western blot analysis that had been symptomatic with chronic fatigue for an average of 12.7 ± 6.6 years. They had been seen by multiple physicians (13.3 ± 7.6 and had used many other remedies, supplements and drugs (14.4 ± 7.4 without fatigue relief. Fatigue was monitored at 0, 7, 30 and 60 days using a validated instrument, the Piper Fatigue Scale.Results: Patients in this preliminary study responded to the combination test supplement, showing a 26% reduction in overall fatigue by the end of the 8-week trial (p< 0.0003. Analysis of subcategories of fatigue indicated that there were significant improvements in the ability to complete tasks and activities as well as significant improvements in mood and cognitive abilities. Regression analysis of the data indicated that reductions in fatigue were consistent and occurred with a high degree of confidence (R2= 0.998. Functional Foods in Health and Disease 2012, 2(3:35-47 Conclusions: The combination supplement was a safe and effective method to significantly reduce intractable fatigue in long-term patients with Western blot-positive ‘chronic Lyme disease.’

  9. Grain surface features and clay mineralogy of the quaternary sediments from Western Deccan Trap Region, India, and their palaeoclimatic significance

    Directory of Open Access Journals (Sweden)

    Veena U. Joshi

    2011-06-01

    Full Text Available Quartz sand grains obtained from a deeply gullied topography along the banks of two tributaries of River Pravara in Maharashtra (India have been examined with a scanning electron microscope (SEM. Quartz grains have been selected after a heavy mineral separation and micro-photographs of each grain were taken at various angles and magnifications. The sediments reveal features resulting from mechanical grinding as well as from chemical alteration. Conchoidal fractures, cleavage planes, grooves, v-shaped indentations etc. are the mechanical features documented on the grains whereas solution pits of varying sizes and intensity, precipitation surfaces, oriented v-pits, solution crevasses and etching are the features of chemical origin. Several evidences indicate that the samples have undergone digenetic changes. Few grains show the features of intense chemical breakdown. The overall assemblages of the grain surface features suggest that the samples have been subjected to subaqueous transport for a considerable period of time. The minor chemical features such as solution pits or semi circular arcuate steps found in abundance on these grains are due to the dissolution of the sediments in a low energy fluviatile environment. For clay mineralogy, fractions between <2 and <0.2 mm were separated out from the sediments. The clay fractions were then subjected to examination by X-ray diffraction (XRD of oriented K/Ca saturated samples using a Philips Diffractometer and Ni-filtered Cu Ka radiation with the scanning speed of 10 2Ө min -1. The main clay minerals for all the samples are identical and show the presence of hydroxy-interlayered smectites with minor quantities of mica, kaolinite, smectites, quartz and feldspar. The first weathering product of the Deccan Basalt (DB is the dioctahedral smectite. Since the present semi aridic climatic condition of the study area can not transform a smectite to HIS and either smectite to kaolin, it is quite likely that

  10. Long-term use of amiodarone before heart transplantation significantly reduces early post-transplant atrial fibrillation and is not associated with increased mortality after heart transplantation

    Directory of Open Access Journals (Sweden)

    Rivinius R

    2016-02-01

    group (P=0.0123. There was no statistically significant difference between patients with and without long-term use of amiodarone prior to HTX in 1-year (P=0.8596, 2-year (P=0.8620, 5-year (P=0.2737, or overall follow-up mortality after HTX (P=0.1049. Moreover, Kaplan–Meier survival analysis showed no statistically significant difference in overall survival (P=0.1786.Conclusion: Long-term use of amiodarone in patients before HTX significantly reduces early post-transplant AF and is not associated with increased mortality after HTX. Keywords: amiodarone, atrial fibrillation, heart failure, heart transplantation, mortality

  11. Taking advantage of reduced droplet-surface interaction to optimize transport of bioanalytes in digital microfluidics.

    Science.gov (United States)

    Freire, Sergio L S; Thorne, Nathaniel; Wutkowski, Michael; Dao, Selina

    2014-11-10

    Digital microfluidics (DMF), a technique for manipulation of droplets, is a promising alternative for the development of "lab-on-a-chip" platforms. Often, droplet motion relies on the wetting of a surface, directly associated with the application of an electric field; surface interactions, however, make motion dependent on droplet contents, limiting the breadth of applications of the technique. Some alternatives have been presented to minimize this dependence. However, they rely on the addition of extra chemical species to the droplet or its surroundings, which could potentially interact with droplet moieties. Addressing this challenge, our group recently developed Field-DW devices to allow the transport of cells and proteins in DMF, without extra additives. Here, the protocol for device fabrication and operation is provided, including the electronic interface for motion control. We also continue the studies with the devices, showing that multicellular, relatively large, model organisms can also be transported, arguably unaffected by the electric fields required for device operation.

  12. Effects of surface morphology on fatigue behavior of reduced activation ferritic/martensitic steel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S.W. [Graduate School of Energy Science, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)]. E-mail: kimsw@iae_kyoto-u.ac.jp; Tanigawa, H. [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai-Mura, Ibaraki-ken 319-1195 (Japan); Hirose, T. [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai-Mura, Ibaraki-ken 319-1195 (Japan); Shiba, K. [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai-Mura, Ibaraki-ken 319-1195 (Japan); Kohyama, A. [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2007-08-01

    Depending on the pulse lengths, the operating conditions, and the thermal conductivity, oscillating temperature gradients will cause elastic and elastic-plastic cyclic deformation giving rise to (creep-)fatigue in the structural first wall and blanket components of fusion systems. In order to perform an accurate fatigue lifetime assessment for the international thermonuclear experimental reactor-test blanket module (ITER-TBM) and advanced systems utilizing the existing data base, mechanical understanding of fatigue fracture is mandatory. In this work, the low cycle fatigue (LCF) properties of F82H IEA heat were examined for three kinds of surface morphology with miniaturized hourglass-type fatigue specimens (SF-1). The assumed fatigue lifetime of cooling channels for ITER-TBM was also compared and assessed by correlating the results of LCF tests performed with SF-1 type specimens. Fracture surfaces and crack initiation sites were investigated by scanning electron microscopy (SEM)

  13. Drag-reducing performance of obliquely aligned superhydrophobic surface in turbulent channel flow

    Science.gov (United States)

    Watanabe, Sho; Mamori, Hiroya; Fukagata, Koji

    2017-04-01

    Friction drag reduction effect by superhydrophobic surfaces in a turbulent channel flow is investigated by means of direct numerical simulation. The simulations are performed under a constant pressure gradient at the friction Reynolds number of 180. A special focus is laid upon the influence of the angle of microridge structure to flow direction, while the gas area fraction on the surface is kept at 50% and the groove width is kept constant at 33.75 wall units. Larger drag reduction effect is observed for a smaller angle: the bulk-mean velocity is increased about 15% when the microridge is parallel to the flow. The drag reduction effect is found to deteriorate rapidly with the microridge angle due to a decrease in the slip velocity. The Reynolds stress budgets show that the modification in each physical effect is qualitatively similar but more pronounced when the microridge is aligned with the stream.

  14. Using squeeze-film effect to reduce surface friction in electrostatic actuators

    DEFF Research Database (Denmark)

    Zsurzsan, Tiberiu-Gabriel; Yamamoto, Akio; Zhang, Zhe;

    2015-01-01

    This paper presents a method of reducing load friction in two degrees-of-freedom (2-DOF) transparent electrostatic induction actuator by using vibration-induced squeeze film effect. An experimental set-up was built to prove the concept. An overall 70% reduction in required driving voltage...

  15. Using squeeze-film effect to reduce surface friction in electrostatic actuators

    DEFF Research Database (Denmark)

    Zsurzsan, Tiberiu-Gabriel; Yamamoto, Akio; Zhang, Zhe

    2015-01-01

    This paper presents a method of reducing load friction in two degrees-of-freedom (2-DOF) transparent electrostatic induction actuator by using vibration-induced squeeze film effect. An experimental set-up was built to prove the concept. An overall 70% reduction in required driving voltage...

  16. Evaluation of an ATP Assay to Quantify Bacterial Attachment to Surfaces in Reduced Gravity

    Science.gov (United States)

    Birmele, Michele N.; Roberson, Luke B.; Roberts, Michael S.

    2010-01-01

    Aim: To develop an assay to quantify the biomass of attached cells and biofilm formed on wetted surfaces in variable-gravity environments. Methods and Results: Liquid cultures of Pseudomonas aeruginosa were exposed to 30-35 brief cycles of hypergravity (ATP luminescent assay accurately reflected cell physiology compared to both cultivation-based and direct-count microscopy analyses. Cells exposed to variable gravity had more than twice as much intracellular ATP as control cells exposed only to normal Earth gravity.

  17. The designer aminoglycoside NB84 significantly reduces glycosaminoglycan accumulation associated with MPS I-H in the Idua-W392X mouse.

    Science.gov (United States)

    Wang, Dan; Belakhov, Valery; Kandasamy, Jeyakumar; Baasov, Timor; Li, Su-Chen; Li, Yu-Teh; Bedwell, David M; Keeling, Kim M

    2012-01-01

    Suppression therapy utilizes compounds that suppress translation termination at in-frame premature termination codons (PTCs) to restore full-length, functional protein. This approach may provide a treatment for diseases caused by nonsense mutations such as mucopolysaccharidosis type I-Hurler (MPS I-H). MPS I-H is a lysosomal storage disease caused by severe α-L-iduronidase deficiency and subsequent lysosomal glycosaminoglycan (GAG) accumulation. MPS I-H represents a good target for suppression therapy because the majority of MPS I-H patients carry nonsense mutations, and restoration of even a small amount of functional α-L-iduronidase may attenuate the MPS I-H phenotype. In this study, we investigated the efficiency of suppression therapy agents to suppress the Idua-W392X nonsense mutation in an MPS I-H mouse model. The drugs tested included the conventional aminoglycosides gentamicin, G418, amikacin, and paromomycin. In addition, the designer aminoglycosides NB54 and NB84, two compounds previously designed to mediate efficient PTC suppression with reduced toxicity, were also examined. Overall, NB84 suppressed the Idua-W392X nonsense mutation much more efficiently than any of the other compounds tested. NB84 treatment restored enough functional α-L-iduronidase activity to partially reverse abnormal GAG accumulation and lysosomal abundance in mouse embryonic fibroblasts derived from the Idua-W392X mouse. Finally, in vivo administration of NB84 to Idua-W392X mice significantly reduced urine GAG excretion and tissue GAG storage. Together, these results suggest that NB84-mediated suppression therapy has the potential to attenuate the MPS I-H disease phenotype. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Studies on Technique of Reducing Methane Emission in a Rice-Duck Ecological System and the Evaluation of Its Economic Significance

    Institute of Scientific and Technical Information of China (English)

    XIANG Pin-gan; HUANG Huang; HUANG Mei; GAN De-xin; ZHOU Yan; FU Zhi-qiang

    2006-01-01

    The rice-duck ecological system is one of the major practices of the traditional Chinese agriculture. A study on the effect of reducing methane emission using this practice provided theoretical and practical basis for further development and utilization of this classical agricultural technique. The effect of reducing methane emission and the economic benefits of rice-duck ecological system were studied by carrying out a field experiment and by using economic methodology. The daily variation of CH4 emission in late rice paddy field was basically consistent with the daily variation of atmospheric temperature. The highest emission occurred at the full tillering stage of late rice with a rate of 24.1 or 32.2 or 40.5 mgm-2 h-1 in no-tillage area with duck and no-tillage area without duck and conventional-tillage area without duck, respectively. The inhibition of methane emission was apparently effective in the rice-duck ecological system during the initial tillering stage and the full tillering stage. Compared to the no-tillage area without duck, methane emission decreased by 2.333 g m-2.Compared to the conventional-tillage area without duck, methane emission decreased by 4.723 g m-2. During the production period of late rice, the amount of methane emission in no-tillage area with duck was 3.373 g m-2 lesser than that of no-tillage area without duck, and 5.59 g m-2 less than that of conventional-tillage without duck area. The economic significance was analyzed. Farmers adopting the rice-duck ecological system obtained 2 166 and 4 207 RMB yuan ha-1 more income than those who adopted a no-tillage without duck technique or conventional-tillage without duck technique, respectively. In addition to the reduction of the environmental pollution by methane emission, the farmers who adopted the rice-duck ecological system achieved economic benefits of 5 000 RMB yuan ha-1, which was 2 206 and 4 274 RMB yuan ha-1 more than those who adopted a no-tillage without duck technique and a

  19. Results of investigations on reducing the lumpiness of gray clay removed from the Kosovo surface mine

    Energy Technology Data Exchange (ETDEWEB)

    Rizvanoli, F.

    1983-04-01

    Tectonic disturbances, fractures, crushing properties and other features of the gray clay overburden reduced the output of bucket wheel excavators and caused frequent breakdowns in mine operation. It was found that clay lumpiness may be reduced by undertaking the following measures: 1) improving bucket wheel design and construction; 2) applying horizontal cutting of clay seams and secondary crushing of excavated clay by installation of a clay crusher on the bucket wheel excavators. The results of 90 days of observation of SRs-470 and SRs-1300 bucket wheel excavators with 6, 16 and 21 buckets are described. On one of the SRs-1300 bucket wheel excavators, a crusher was installed in order to avoid breakdowns in operation of excavator, belt conveyor system and waste stackers. (4 refs.) (In Serbo-Croat)

  20. Ion sulphuration-an effective surface engineering technique for reducing friction and wear of rubbing-pairs

    Institute of Scientific and Technical Information of China (English)

    LIU Jia-jun; WANG Hai-dou; ZHANG Ning; ZHANG Da-ming

    2004-01-01

    The low temperature ion sulphuration-an effective surface engineering technique for reducing friction and wear of rubbing-pairs was introduced. It involves the principle of ion sulphuration process, microstructure of FeS film on 1045 steel, tribological properties of FeS film on steels, microstructions and tribological properties of MoS2 and nano-FeS/MoS2 multi-layered films, as well as their applications.

  1. A Retrospective Study on the Significance of Liver Biopsy and Hepatitis B Surface Antigen in Chronic Hepatitis B Infection.

    Science.gov (United States)

    Zeng, Da-Wu; Zhang, Jie-Min; Liu, Yu-Rui; Dong, Jing; Jiang, Jia-Ji; Zhu, Yue-Yong

    2016-02-01

    To investigate changes in the HBV replication level along with the natural course of chronic HBV infection and to examine the accuracy of the immune tolerant phase defined by the serological profile.A total of 390 chronic HBV-infected patients were retrospectively recruited for this study. They were classified into immune-tolerance (IT), immune-clearance (IC), low-replicative (LR), and HBeAg-negative hepatitis (ENH) phases according to serological profiles (single-standard, SS) or dual-standard (DS) with the inclusion of liver histology. Serum HBV DNA and HBsAg were quantitatively measured, and liver histology was quantitatively analyzed.The accuracy of the SS-defined IT phase was low, and active pathological changes were detected in 56 of 112 SS-defined IT patients. DS-defined IT patients had higher HBsAg levels (P = 0.0002) than the SS-defined patients. The quantitative HBsAg level can help identify SS-defined IT patients with potential liver injury. The area under the received operating characteristic curve for predicting the DS-defined IT phase was 0.831 (HBsAg 4.398 log IU/mL; sensitivity 87.5%; specificity 73.2%). HBV DNA was reduced by 4 logs, whereas HBsAg was only decreased by 2 logs with HBeAg positive to negative phase conversion.Approximately half of IT patients defined by SS may have medium or severe liver injury. Quantitative measurement of the HBsAg level can help identify SS-defined IT patients with potential liver injury.

  2. Mass Administration of Ivermectin for the Elimination of Onchocerciasis Significantly Reduced and Maintained Low the Prevalence of Strongyloides stercoralis in Esmeraldas, Ecuador.

    Directory of Open Access Journals (Sweden)

    Mariella Anselmi

    2015-11-01

    Full Text Available To evaluate the effect of ivermectin mass drug administration on strongyloidiasis and other soil transmitted helminthiases.We conducted a retrospective analysis of data collected in Esmeraldas (Ecuador during surveys conducted in areas where ivermectin was annually administered to the entire population for the control of onchocerciasis. Data from 5 surveys, conducted between 1990 (before the start of the distribution of ivermectin and 2013 (six years after the interruption of the intervention were analyzed. The surveys also comprised areas where ivermectin was not distributed because onchocerciasis was not endemic. Different laboratory techniques were used in the different surveys (direct fecal smear, formol-ether concentration, IFAT and IVD ELISA for Strongyloides stercoralis.In the areas where ivermectin was distributed the strongyloidiasis prevalence fell from 6.8% in 1990 to zero in 1996 and 1999. In 2013 prevalence in children was zero with stool examination and 1.3% with serology, in adult 0.7% and 2.7%. In areas not covered by ivermectin distribution the prevalence was 23.5% and 16.1% in 1996 and 1999, respectively. In 2013 the prevalence was 0.6% with fecal exam and 9.3% with serology in children and 2.3% and 17.9% in adults. Regarding other soil transmitted helminthiases: in areas where ivermectin was distributed the prevalence of T. trichiura was significantly reduced, while A. lumbricoides and hookworms were seemingly unaffected.Periodic mass distribution of ivermectin had a significant impact on the prevalence of strongyloidiasis, less on trichuriasis and apparently no effect on ascariasis and hookworm infections.

  3. Mass Administration of Ivermectin for the Elimination of Onchocerciasis Significantly Reduced and Maintained Low the Prevalence of Strongyloides stercoralis in Esmeraldas, Ecuador

    Science.gov (United States)

    Anselmi, Mariella; Buonfrate, Dora; Guevara Espinoza, Angel; Prandi, Rosanna; Marquez, Monica; Gobbo, Maria; Montresor, Antonio; Albonico, Marco; Racines Orbe, Marcia; Bisoffi, Zeno

    2015-01-01

    Objectives To evaluate the effect of ivermectin mass drug administration on strongyloidiasis and other soil transmitted helminthiases. Methods We conducted a retrospective analysis of data collected in Esmeraldas (Ecuador) during surveys conducted in areas where ivermectin was annually administered to the entire population for the control of onchocerciasis. Data from 5 surveys, conducted between 1990 (before the start of the distribution of ivermectin) and 2013 (six years after the interruption of the intervention) were analyzed. The surveys also comprised areas where ivermectin was not distributed because onchocerciasis was not endemic. Different laboratory techniques were used in the different surveys (direct fecal smear, formol-ether concentration, IFAT and IVD ELISA for Strongyloides stercoralis). Results In the areas where ivermectin was distributed the strongyloidiasis prevalence fell from 6.8% in 1990 to zero in 1996 and 1999. In 2013 prevalence in children was zero with stool examination and 1.3% with serology, in adult 0.7% and 2.7%. In areas not covered by ivermectin distribution the prevalence was 23.5% and 16.1% in 1996 and 1999, respectively. In 2013 the prevalence was 0.6% with fecal exam and 9.3% with serology in children and 2.3% and 17.9% in adults. Regarding other soil transmitted helminthiases: in areas where ivermectin was distributed the prevalence of T. trichiura was significantly reduced, while A. lumbricoides and hookworms were seemingly unaffected. Conclusions Periodic mass distribution of ivermectin had a significant impact on the prevalence of strongyloidiasis, less on trichuriasis and apparently no effect on ascariasis and hookworm infections. PMID:26540412

  4. Reduced gastric acid production in burn shock period and its significance in the prevention and treatment of acute gastric mucosal lesions

    Institute of Scientific and Technical Information of China (English)

    Li Zhu; Zhong Cheng Yang; Ao Li; De Chang Cheng

    2000-01-01

    AIM To investigate the changes of gastric acid production and its mechanism in shock period of severe burn in rats.METHODS A rat model with 30% TBSA fullthickness burn injury was employed and the gastric acid production, together with gastric mucosal blood flow (GMBF) and energy charge ( EC ) were measured serially within 48h postburn.RESULTS The gastric acid production in the acute shock period was markedly inhibited after severe burn injury. At the 3rd h postburn, the gastric juice volume, total acidity and acid output were already significantly decreased (P<0.01), and reached the lowest point,0.63mL/L ± 0.20mL/L, 10.81mmol/L ±2.58mmol/L and 2.23 mmol/h ± 0.73mmol/h respectively, at the 12th h postburn. Although restored to some degree 24 h after thermal injury, the variables above were still statistically lower, compared with those of control animals at the 48th h postburn. The GMBF and EC were also significantly reduced after severe burns, consistent with the trend of gastric acid production changes.CONCLUSION Gastric acid production, as well as GMBF and EC was predominantly decreased in the early postburn stage, suggesting that gastric mucosal ischemia and hypoxia with resultant disturbance in energy metabolism, but not gastric acid proper, might be the decisive factor in the pathogenesis of AGML after thermal injury, and that the preventive use of anti-acid drugs during burn shock period was unreasonable in some respects. Therefore,taking effective measures to improve gastric mucosal blood perfusion as early as possible postburn might be more preferable for the AGML prevention and treatment.

  5. Surface Breakdown of Printed Circuit Board under Magnetic Field with Reduced Pressure

    Institute of Scientific and Technical Information of China (English)

    杜伯学; 朱晓辉; 高宇; 卢欣

    2010-01-01

    Epoxy resin laminate onto which a pair of copper foil was printed was employed as test samples.The samples were placed in an artificial atmospheric chamber, which was vacuumed by a rotary pump from 100 kPa to 5 kPa.The magnetic field was produced by permanent magnets that were assembled to make E×B drift away from, into and parallel to the sample surface, respectively.Magnetic flux density was adjusted at 120 mT, 180 mT and 240 mT respectively.By applying a negative bias voltage between the electrodes, the ...

  6. Thorium Enrichment within the Procellarum KREEP Terrane: The Record in Surface Deposits and Significance for Thermal Evolution

    Science.gov (United States)

    Jolliff, B. L.; Gillis, J. J.; Haskin, L. A.

    1999-01-01

    The nearside-farside structural and compositional asymmetry of the Moon was recognized during the early days of Apollo and the suggestion was made that the migration of mantle melts to the nearside would have been favored by early Earth-Moon orbital dynamics and nonuniform planetesimal bombardment. Recent global geochemical mapping by Lunar Prospector has provided additional data, particularly in the Th distribution, that strongly supports the notion of global, preferential melt migration, which led in part to the development of the Procellarum KREEP Terrane (PKT) [2-5]. The surface distribution of Th was then reshaped by basin-forming impacts into the PKT, especially the Imbrium impact, which was the last and largest to strike in that region. The Imbrium event probably excavated material from a partially molten zone deep in the crust and delivered Th-rich ejecta Moon-wide. A fundamentally important but poorly understood aspect of the global Th distribution is the concentration of Th in the subsurface rocks of the PKT crustal section. For example, depending on what assumptions are made, the PKT crustal section, which is about 12% of the crust and only about 1.2% of the whole Moon, may contain as much as 40% of the Moon's entire Th budget. Such a distribution of Th and related heat-producing elements would have had a profound effect on melting, mixing, and the thermal evolution of the PKT and the underlying mantle. In this abstract, we examine the compositions of terra formations within the PKT and relate them to some of the Th-bearing rock types known from the Apollo samples. It appears that the existence of the PKT may be a unifying concept for a number of petrologic and geochemical observations. From the initial Lunar Prospector gamma-ray spectrometer data(-about 5 deg. resolution) and from the preliminary low-orbit data, there appears to be a number of relatively hotter "spots" within the PKT in terms of Th concentration. Some of the hotter spots correspond to

  7. Silanization of inner surfaces of nanoelectrospray ionization emitters for reduced analyte adsorption.

    Science.gov (United States)

    Choi, Yong Seok; Wood, Troy D

    2008-04-01

    During the course of nanoelectrospray ionization (nanoESI) of substance P, an unusual type of signal reduction was observed with flow rates silanized. Emitters treated with hexamethyldisilazane or 3-aminopropyltriethoxysilane showed higher analyte signals for substance P than untreated emitters, suggesting a reduction of analyte adsorption onto the inner walls of silanized emitters. The efficacy of reduced peptide adsorption was demonstrated for emitters silanized with 3-aminopropyltriethoxysilane using a simple peptide mixture as well as a more complex peptide mixture (a tryptic digest of horse hemoglobin).

  8. Prime focus architectures for large space telescopes: reduce surfaces to save cost

    Science.gov (United States)

    Breckinridge, J. B.; Lillie, C. F.

    2016-07-01

    Conceptual architectures are now being developed to identify future directions for post JWST large space telescope systems to operate in the UV Optical and near IR regions of the spectrum. Here we show that the cost of optical surfaces within large aperture telescope/instrument systems can exceed $100M/reflection when expressed in terms of the aperture increase needed to over come internal absorption loss. We recommend a program in innovative optical design to minimize the number of surfaces by considering multiple functions for mirrors. An example is given using the Rowland circle imaging spectrometer systems for UV space science. With few exceptions, current space telescope architectures are based on systems optimized for ground-based astronomy. Both HST and JWST are classical "Cassegrain" telescopes derived from the ground-based tradition to co-locate the massive primary mirror and the instruments at the same end of the metrology structure. This requirement derives from the dual need to minimize observatory dome size and cost in the presence of the Earth's 1-g gravitational field. Space telescopes, however function in the zero gravity of space and the 1- g constraint is relieved to the advantage of astronomers. Here we suggest that a prime focus large aperture telescope system in space may have potentially have higher transmittance, better pointing, improved thermal and structural control, less internal polarization and broader wavelength coverage than Cassegrain telescopes. An example is given showing how UV astronomy telescopes use single optical elements for multiple functions and therefore have a minimum number of reflections.

  9. Dexamethasone reduces cell surface levels of CD11b on human eosinophils

    Directory of Open Access Journals (Sweden)

    A. M. Das

    1997-01-01

    Full Text Available Overnight incubation of human eosinophils (Eøs with the glucocorticoid hormone dexamethasone (DEX; 0.1 μM resulted in lower expression of the CD11b, but not CD49d, antigen on their plasma membrane, as assessed by flow cytometry. DEX produced a consistent inhibitory effect (ranging from 16% to 20% when tested at a concentration of 0.1 μM. Eø stimulation with 100 ng/ml eotaxin produced an increase in CD11b (+26%, but not CD11c, levels and concomitantly a reduction (–25% on CD62L expression. The inhibition exerted by DEX upon CD11b levels was also evident following eotaxin upregulation, with a degree of inhibition similar to that seen on basal levels. These data highlight a novel mechanism of action by which glucocorticoid hormones may be effective in reducing Eø accumulation during allergic inflammation in man.

  10. Holstein-Friesian calves selected for divergence in residual feed intake during growth exhibited significant but reduced residual feed intake divergence in their first lactation.

    Science.gov (United States)

    Macdonald, K A; Pryce, J E; Spelman, R J; Davis, S R; Wales, W J; Waghorn, G C; Williams, Y J; Marett, L C; Hayes, B J

    2014-03-01

    Residual feed intake (RFI), as a measure of feed conversion during growth, was estimated for around 2,000 growing Holstein-Friesian heifer calves aged 6 to 9 mo in New Zealand and Australia, and individuals from the most and least efficient deciles (low and high RFI phenotypes) were retained. These animals (78 New Zealand cows, 105 Australian cows) were reevaluated during their first lactation to determine if divergence for RFI observed during growth was maintained during lactation. Mean daily body weight (BW) gain during assessment as calves had been 0.86 and 1.15 kg for the respective countries, and the divergence in RFI between most and least efficient deciles for growth was 21% (1.39 and 1.42 kg of dry matter, for New Zealand and Australia, respectively). At the commencement of evaluation during lactation, the cows were aged 26 to 29 mo. All were fed alfalfa and grass cubes; it was the sole diet in New Zealand, whereas 6 kg of crushed wheat/d was also fed in Australia. Measurements of RFI during lactation occurred for 34 to 37 d with measurements of milk production (daily), milk composition (2 to 3 times per week), BW and BW change (1 to 3 times per week), as well as body condition score (BCS). Daily milk production averaged 13.8 kg for New Zealand cows and 20.0 kg in Australia. No statistically significant differences were observed between calf RFI decile groups for dry matter intake, milk production, BW change, or BCS; however a significant difference was noted between groups for lactating RFI. Residual feed intake was about 3% lower for lactating cows identified as most efficient as growing calves, and no negative effects on production were observed. These results support the hypothesis that calves divergent for RFI during growth are also divergent for RFI when lactating. The causes for this reduced divergence need to be investigated to ensure that genetic selection programs based on low RFI (better efficiency) are robust. Copyright © 2014 American Dairy

  11. Effects of continuous casting mould fluxes on reducing longitudinal and star cracks on a slab surface

    Institute of Scientific and Technical Information of China (English)

    WANG Qian; WANG Yu; CHI Jinghao; XIE Bing; HE Yuming; ZHU Bing; CHEN Wenman

    2004-01-01

    In the continuous casting production of medium carbon steel (whose mass fraction of carbon is 0.09 % to 0.16 %)and high strength Iow alloy steel (whose mass fraction of Mn is 0.90 % to 1.40 %), flecks occurring the most often are usually longitudinal and star cracks. In additional to the employment of a galvanized plate mould, two kinds; of fluxes with special properties were studied and used to harmonize the conflicts between the function of heat transfer and lubrication. An industrial application revealed that the crystallizing temperature (To) and crystal ratio (R) of fluxes have a crucible effect on impeding the occurrence of above defects on a slab surface. In the case of slab section (180 to 240) mm×(1000 to 1400) mm and casting speed Vc of (0.7 to 1.2) m/min, the optimized parameters of fluxes are Tc of (1170 to 1190) ℃, R of 80 % to 95 % for medium carbon steel, and Tc of (1100 to 1150) ℃, plus R of 40 % to 60 % for high strength Iow alloy steel.

  12. Smaller shoes : new pipeline trenching and wellsite road building practices reduce Devon's surface impacts

    Energy Technology Data Exchange (ETDEWEB)

    Stastny, R.P.

    2010-03-15

    This article reported on a strategy launched by Devon in collaboration with petroleum producers and landowners to minimize pipeline surface disturbance. Known as the Innovative Pipelining Strategies, it reduces right-of-way impacts by about 50 per cent. The strategy has earned Devon a Stewardship of Excellence Award from the Canadian Association of Petroleum Producers. As farmers are increasingly adopting low-till or no-till agricultural practices, they are less tolerant of sunken trenches for pipelines, and dislike the inefficiency of having to work around freshly laid pipes, the lost productivity associated with pipeline right-of-ways in the first year, and having to deal with other topsoil issues. Although technically any soil excavated from a trench should go back into the same trench, it does not always fit back in once it has been brought to surface. Excess soil must then be spread over the width of the right-of-way where spring melt and rains can often make a mess of it. Devon's solution is to use a wheel packer or other tamping device to ensure that all the dirt fits back in the trench. Compacting the dirt solves the problem of sunken ditches. Right-of-way land can immediately return to production. Compacting also reduces the width of topsoil stripping, and the trench itself can be narrower. Devon has gone from stripping 10 to 15 metres of topsoil down to just 1 metre. A 3 to 5 foot wide excavation has been reduced to under 2 feet. Right-of-ways in forested areas have been reduced from 15 metres in width to 12 metres. Compacting trench dirt has the added advantage of reducing stress on the pipe and water incursion into the ditch through unconsolidated soil, which minimizes soil erosion. Although packing dirt adds initial cost, the full-cycle costs are lower due to minimal spring cleanup requirements, fewer field grading issues and fewer pipeline repair incidents. 4 figs.

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

    Directory of Open Access Journals (Sweden)

    D. O. Topping

    2006-11-01

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

  14. Experiments on bubble generation by a hydrofoil moving beneath the water surface for reducing ship drag

    Science.gov (United States)

    Kumagai, Ichiro; Murai, Yuichi; Takahashi, Yoshiaki; Sakamaki, Haruki; Tsukahara, Takahiro; Ozaki, Tsubasa; Tasaka, Yuji; Oishi, Yoshihiko

    2014-04-01

    We have invented two types of hydrofoil bubble generator for drag reduction of ship that can reduce the energy for air bubble generation on the ship hull. Their fundamental process of air entrainment and subsequent bubble generation by the hydrofoil facility are described by a simple fluid dynamic model. We experimentally determined the critical velocity of the bubble generation and the relationship between air volume flow rate and the hydrofoil velocity. The magnitude of the negative pressure produced above the hydrofoil, which is a driving force of the air entrainment, depends on the shape of the hydrofoil, gap ratio (normalized depth of the hydrofoil), Reynolds number, Froude number, and angle of attack. Recent applications of the drag-reduction technology with air bubbles to a ship save about 10%-15% of the total energy consumption of the ship. The device works as a self-priming pump when the draft of the ship is shallow (hydrofoil depends on the flow condition around the hydrofoil, proper operation of compressors is necessary. We also show experimental results on optimization of hydrofoils to enhance the hydrofoil performance of air entrainment and air bubble generation.

  15. Investigations of surface coatings to reduce memory effect in plastic scintillator detectors used for radioxenon detection

    Science.gov (United States)

    Bläckberg, L.; Fay, A.; Jõgi, I.; Biegalski, S.; Boman, M.; Elmgren, K.; Fritioff, T.; Johansson, A.; Mårtensson, L.; Nielsen, F.; Ringbom, A.; Rooth, M.; Sjöstrand, H.; Klintenberg, M.

    2011-11-01

    In this work Al2O3 and SiO2 coatings are tested as Xe diffusion barriers on plastic scintillator substrates. The motivation is improved beta-gamma coincidence detection systems, used to measure atmospheric radioxenon within the verification regime of the Comprehensive Nuclear-Test-Ban Treaty. One major drawback with the current setup of these systems is that the radioxenon tends to diffuse into the plastic scintillator material responsible for the beta detection, resulting in an unwanted memory effect. Here, coatings with thicknesses between 20 and 900 nm have been deposited onto plastic scintillators, and investigated using two different experimental techniques. The results show that all tested coatings reduce the Xe diffusion into the plastic. The reduction is observed to increase with coating thickness for both coating materials. The 425 nm Al2O3 coating is the most successful one, presenting a diffusion reduction of a factor 100, compared to uncoated plastic. In terms of memory effect reduction this coating is thus a viable solution to the problem in question.

  16. Investigations of surface coatings to reduce memory effect in plastic scintillator detectors used for radioxenon detection

    Energy Technology Data Exchange (ETDEWEB)

    Blaeckberg, L., E-mail: lisa.blackberg@physics.uu.se [Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120 Uppsala (Sweden); Fay, A. [University of Texas at Austin, Nuclear Engineering Teaching Lab, J.J. Pickle Research Campus, R-9000 Austin, TX (United States); Jogi, I. [Department of Materials Chemistry, Uppsala University, Box 538, SE-75121 Uppsala (Sweden); Biegalski, S. [University of Texas at Austin, Nuclear Engineering Teaching Lab, J.J. Pickle Research Campus, R-9000 Austin, TX (United States); Boman, M. [Department of Materials Chemistry, Uppsala University, Box 538, SE-75121 Uppsala (Sweden); Elmgren, K.; Fritioff, T. [Division of Defence and Security Systems, Swedish Defence Research Agency (FOI), SE-17290 Stockholm (Sweden); Johansson, A. [Nanexa AB, Virdings Alle 32B, SE-75450 Uppsala (Sweden); Martensson, L.; Nielsen, F.; Ringbom, A. [Division of Defence and Security Systems, Swedish Defence Research Agency (FOI), SE-17290 Stockholm (Sweden); Rooth, M. [Nanexa AB, Virdings Alle 32B, SE-75450 Uppsala (Sweden); Sjoestrand, H.; Klintenberg, M. [Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120 Uppsala (Sweden)

    2011-11-11

    In this work Al{sub 2}O{sub 3} and SiO{sub 2} coatings are tested as Xe diffusion barriers on plastic scintillator substrates. The motivation is improved beta-gamma coincidence detection systems, used to measure atmospheric radioxenon within the verification regime of the Comprehensive Nuclear-Test-Ban Treaty. One major drawback with the current setup of these systems is that the radioxenon tends to diffuse into the plastic scintillator material responsible for the beta detection, resulting in an unwanted memory effect. Here, coatings with thicknesses between 20 and 900 nm have been deposited onto plastic scintillators, and investigated using two different experimental techniques. The results show that all tested coatings reduce the Xe diffusion into the plastic. The reduction is observed to increase with coating thickness for both coating materials. The 425 nm Al{sub 2}O{sub 3} coating is the most successful one, presenting a diffusion reduction of a factor 100, compared to uncoated plastic. In terms of memory effect reduction this coating is thus a viable solution to the problem in question.

  17. Imprint Molding of a Microfluidic Optical Cell on Thermoplastics with Reduced Surface Roughness for the Detection of Copper Ions.

    Science.gov (United States)

    Wu, Jing; Lee, Nae Yoon

    2016-01-01

    Here, we introduce a simple and facile technique for fabricating microfluidic optical cells by utilizing a micropatterned polymer mold, followed by imprinting on thermoplastic substrates. This process has reduced the surface roughness of the microchannel, making it suitable for microscale optical measurements. The micropatterned polymer mold was fabricated by first micromilling on a poly(methylmethacrylate) (PMMA) substrate, and then transferring the micropattern onto an ultraviolet (UV)-curable optical adhesive. After an anti-adhesion treatment of the polymer mold fabricated using the UV-curable optical adhesive, the polymer mold was used repeatedly for imprinting onto various thermoplastics, such as PMMA, polycarbonate (PC), and poly(ethyleneterephthalate) (PET). The roughness values for the PMMA, PC, and PET microchannels were approximately 11.3, 20.3, and 14.2 nm, respectively, as compared to those obtained by micromilling alone, which were 15.9, 76.8, and 207.5 nm, respectively. Using the imprint-molded thermoplastic optical cell, rhodamine B and copper ions were successfully quantified. The reduced roughness of the microchannel surface resulted in improved sensitivity and reduced noise, paving the way for integration of the detection module so as to realize totally integrated microdevices.

  18. The Friction Reducing Effect of Square-Shaped Surface Textures under Lubricated Line-Contacts—An Experimental Study

    Directory of Open Access Journals (Sweden)

    Ping Lu

    2016-07-01

    Full Text Available Surface texturing has been shown to be an effective modification approach for improving tribological performance. This study examined the friction reduction effect generated by square dimples of different sizes and geometries. Dimples were fabricated on the surface of ASP2023 steel plates using femtosecond laser-assisted surface texturing techniques, and reciprocating sliding line contact tests were carried out on a Plint TE77 tribometer using a smooth 52100 bearing steel roller and textured ASP2023 steel plates. The tribological characterization of the friction properties indicated that the textured samples had significantly lowered the friction coefficient in both boundary (15% improvement and mixed lubrication regimes (13% improvement. Moreover, the high data sampling rate results indicated that the dimples work as lubricant reservoirs in the boundary lubrication regime.

  19. Water in the hydration shell of halide ions has significantly reduced Fermi resonance and moderately enhanced Raman cross section in the OH stretch regions.

    Science.gov (United States)

    Ahmed, Mohammed; Singh, Ajay K; Mondal, Jahur A; Sarkar, Sisir K

    2013-08-22

    Water in the presence of electrolytes plays an important role in biological and industrial processes. The properties of water, such as the intermolecular coupling, Fermi resonance (FR), hydrogen-bonding, and Raman cross section were investigated by measuring the Raman spectra in the OD and OH stretch regions in presence of alkali halides (NaX; X = F, Cl, Br, I). It is observed that the changes in spectral characteristics by the addition of NaX in D2O are similar to those obtained by the addition of H2O in D2O. The spectral width decreases significantly by the addition of NaX in D2O (H2O) than that in the isotopically diluted water. Quantitative estimation, on the basis of integrated Raman intensity, revealed that the relative Raman cross section, σ(H)/σ(b) (σ(H) and σ(b) are the average Raman cross section of water in the first hydration shell of X(-) and in bulk, respectively), in D2O and H2O is higher than those in the respective isotopically diluted water. These results suggest that water in the hydration shell has reduced FR and intermolecular coupling compared to those in bulk. In the isotopically diluted water, the relative Raman cross section increases with increase in size of the halide ions (σ(H)/σ(b) = 0.6, 1.1, 1.5, and 1.9 for F(-), Cl(-), Br(-), and I(-), respectively), which is assignable to the enhancement of Raman cross section by charge transfer from halide ions to the hydrating water. Nevertheless, the experimentally determined σ(H)/σ(b) is lower than the calculated values obtained on the basis of the energy of the charge transfer state of water. The weak enhancement of σ(H)/σ(b) signifies that the charge transfer transition in the hydration shell of halide ions causes little change in the OD (OH) bond lengths of hydrating water.

  20. Rhamnolipids elicit the same cytotoxic sensitivity between cancer cell and normal cell by reducing surface tension of culture medium.

    Science.gov (United States)

    Jiang, Lifang; Shen, Chong; Long, Xuwei; Zhang, Guoliang; Meng, Qin

    2014-12-01

    Biosurfactant rhamnolipids have been claimed to show biological activities of inhibiting the proliferation of cancer cells. In this study, the cytotoxicity of rhamnolipids was examined on four cancer cells (HepG2, Caco-2, Hela, MCF-7 cells) and two normal cells (HK-2 cell, primary hepatocyte). Interestingly, both cancer cells and normal cells exhibited similar sensitivities to the addition of rhamnolipids in culture medium, and the cytotoxicity was largely attenuated by the presence of fetal bovine serum (FBS) in culture medium. In correlation of the mono-/di-rhamnolipid cytotoxicity with the surface tension of culture medium, it was found that rhamnolipids triggered cytotoxicity whenever the surface tension of culture medium decreased below 41 mN/m irrespective of the FBS content in culture medium, cell line, or rhamnolipid congener. Similarly, each chemical surfactant (Tween-80, sodium dodecyl sulfate, and sodium dodecyl benzene sulfonate) could cause cytotoxicity on HepG2 cells whenever its addition made the surface tension under 41 mN/m in culture medium with or without the presence of FBS. It seems that rhamnolipids, like chemical surfactants, exhibited cytotoxicity by reducing the surface tension of culture medium rather than by changing its specific molecular structure, which had no selection on tumor cells. This study could offer helps to correct the misleading biological activity of rhamnolipids and to avoid the possible large wastes of time and expenses on developing the applications in antitumor drugs.

  1. Gold Cluster Diffusion Kinetics on Stoichiometric and Reduced Surfaces of Rutile TiO 2 (110)

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, Nir; Browning, Nigel D.

    2011-06-16

    Gold clusters on rutile TiO2 are known to serve as efficient oxidation catalysts for pollutants and environmental contaminants. However, the mechanism by which highly mobile small clusters migrate and aggregate into larger species relevant to gold’s catalytic activity remains unresolved. We report herein on ab initio simulations of the diffusion of atomic gold clusters up to the trimer on rutile TiO2(110) surfaces. We show that, on the stoichiometric surface, both the dimer and the trimer can exhibit relatively low surface mobility due to high energetic barriers for diffusion out of their energetic minima coupled with low barriers for the reverse motion. On the reduced surface, these clusters can diffuse relatively quickly between energetic minima within the oxygen vacancy site due to the large degree of vibrational entropy in their transition states. Our computed diffusion times provide a point of comparison for future experiments and will aid in development of models of gold cluster island sintering.

  2. Peripheral snap-fit locking mechanisms and smooth surface finish of tibial trays reduce backside wear in fixed-bearing total knee arthroplasty.

    Science.gov (United States)

    Łapaj, Łukasz; Mróz, Adrian; Kokoszka, Paweł; Markuszewski, Jacek; Wendland, Justyna; Helak-Łapaj, Celina; Kruczyński, Jacek

    2017-02-01

    Background and purpose - Severe backside wear, observed in older generations of total knee replacements (TKRs), led to redesign of locking mechanisms to reduce micromotions between tibial tray and inlay. Since little is known about whether this effectively reduces backside wear in modern designs, we examined backside damage in retrievals of various contemporary fixed-bearing TKRs. Patients and methods - A consecutive series of 102 inlays with a peripheral (Stryker Triathlon, Stryker Scorpio, DePuy PFC Sigma, Aesculap Search Evolution) or dovetail locking mechanism (Zimmer NexGen, Smith and Nephew Genesis II) was examined. Articular and backside surface damage was evaluated using the semiquantitative Hood scale. Inlays were examined using scanning electron microscopy (SEM) to determine backside wear mechanisms. Results - Mean Hood scores for articular (A) and backside (B) surfaces were similar in most implants-Triathlon (A: 46, B: 22), Genesis II (A: 55, B: 24), Scorpio (A: 57, B: 24), PFC (A: 52, B: 20); Search (A: 56, B: 24)-except the NexGen knee (A: 57, B: 60), which had statistically significantly higher backside wear scores. SEM studies showed backside damage caused by abrasion related to micromotion in designs with dovetail locking mechanisms, especially in the unpolished NexGen trays. In implants with peripheral liner locking mechanism, there were no signs of micromotion or abrasion. Instead, "tray transfer" of polyethylene and flattening of machining was observed. Interpretation - Although this retrieval study may not represent well-functioning TKRs, we found that a smooth surface finish and a peripheral locking mechanism reduce backside wear in vivo, but further studies are required to determine whether this actually leads to reduced osteolysis and lower failure rates.

  3. Peripheral snap-fit locking mechanisms and smooth surface finish of tibial trays reduce backside wear in fixed-bearing total knee arthroplasty

    Science.gov (United States)

    Łapaj, Łukasz; Mróz, Adrian; Kokoszka, Paweł; Markuszewski, Jacek; Wendland, Justyna; Helak-Łapaj, Celina; Kruczyński, Jacek

    2017-01-01

    Background and purpose — Severe backside wear, observed in older generations of total knee replacements (TKRs), led to redesign of locking mechanisms to reduce micromotions between tibial tray and inlay. Since little is known about whether this effectively reduces backside wear in modern designs, we examined backside damage in retrievals of various contemporary fixed-bearing TKRs. Patients and methods — A consecutive series of 102 inlays with a peripheral (Stryker Triathlon, Stryker Scorpio, DePuy PFC Sigma, Aesculap Search Evolution) or dovetail locking mechanism (Zimmer NexGen, Smith and Nephew Genesis II) was examined. Articular and backside surface damage was evaluated using the semiquantitative Hood scale. Inlays were examined using scanning electron microscopy (SEM) to determine backside wear mechanisms. Results — Mean Hood scores for articular (A) and backside (B) surfaces were similar in most implants—Triathlon (A: 46, B: 22), Genesis II (A: 55, B: 24), Scorpio (A: 57, B: 24), PFC (A: 52, B: 20); Search (A: 56, B: 24)—except the NexGen knee (A: 57, B: 60), which had statistically significantly higher backside wear scores. SEM studies showed backside damage caused by abrasion related to micromotion in designs with dovetail locking mechanisms, especially in the unpolished NexGen trays. In implants with peripheral liner locking mechanism, there were no signs of micromotion or abrasion. Instead, “tray transfer” of polyethylene and flattening of machining was observed. Interpretation — Although this retrieval study may not represent well-functioning TKRs, we found that a smooth surface finish and a peripheral locking mechanism reduce backside wear in vivo, but further studies are required to determine whether this actually leads to reduced osteolysis and lower failure rates. PMID:27781667

  4. Use of New Water Soluble Surface Film—Forming Material to Reduce Ammonia Loss from Water Solution

    Institute of Scientific and Technical Information of China (English)

    YINBIN; SHENRENFANG; 等

    1996-01-01

    A new water soluble surface film-forming material was developed and its effect on reducing ammonia volatilization from an alkaline solution was investigated in laboratory,Results showed that the new film formed by the material was not only more effective in reducing ammonia loss than any other films tested but also much cheaper.The optimum amount of addition of the new film-forming material was about 10times the theoretical amount to form a monomolecular film.Under the experimental conditions,the new film could effectively depress the ammonia volatilization for at least 6 days.The cumulative ammonia loss rates for different films were fitted to a simple logistic equation ,and some important parameters such as the cumulative loss,and the maximum and average volatilization rates were calculated.The effect of different films could be,therefore,compared quantitatively,indicating the new film was most effective in depressing ammonia volatilization.

  5. Surface modification of poly(vinyl chloride) by physisorbed free radical initiation for reduced plasticizer migration and antimicrobial properties

    Science.gov (United States)

    McGinty, Kathryn

    Poly(vinyl chloride), PVC, is a particularly important commodity polymer that accounts for an annual world-wide production of 26 million tons. It is used frequently in the medical field as blood storage bags, endotracheal and dialysis tubing and intravenous catheters. Common plasticizers, namely di(2-ethylhexyl) phthalate (DEHP), are added to PVC to improve the processability and flexibility by lowering the glass transition temperature. However, most phthalate plasticizers are potential carcinogens. There has been extensive research on PVC with surface coatings to improve biocompatibility, surface crosslinking to create a barrier to the plasticizer leaching and surface grafting of hydrophilic polymers for both biocompatibility and reduced plasticizer migration. A novel surface grafting technique is the grafting of hydrophilic monomers by physisorbed free radical initiators. This modification method can be applied to PVC to attach vinyl hydrophilic monomers by the "grafting from" method. This approach, extending on earlier work involving polymer brush formation on poly(dimethylsiloxane), involves a two-step process: physisorption of a hydrophobic free radical initiator onto a polymer surface followed by radical polymerization of hydrophilic monomers in water. The key step is creating a hydrophobic/hydrophilic diffusional barrier that promotes radical reactions at the polymer surface. Polymers that have been successfully grafted from PVC films and tubing include: poly(hydroxyethyl methacrylate) (PHEMA), poly(dimethylacrylamide) (PDMA), poly(hydroxyethyl acrylate) (PHEA), poly(dimethylaminoethyl methacrylate) (PDMAEMA), poly(acrylic acid) (PAA), and poly(4-vinylpyridine) (P4VP). Characterization methods performed include bulk chemical composition by transmission infrared spectroscopy, surface composition using X-ray photoelectron spectroscopy, surface wettability by tensiometry and capillary rise, film thickness determination by infrared, gravimetric analysis and UV

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

    Directory of Open Access Journals (Sweden)

    D. O. Topping

    2007-01-01

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

  7. Silver deposition on titanium surface by electrochemical anodizing process reduces bacterial adhesion of Streptococcus sanguinis and Lactobacillus salivarius.

    Science.gov (United States)

    Godoy-Gallardo, Maria; Rodríguez-Hernández, Ana G; Delgado, Luis M; Manero, José M; Javier Gil, F; Rodríguez, Daniel

    2015-10-01

    The aim of this study was to determine the antibacterial properties of silver-doped titanium surfaces prepared with a novel electrochemical anodizing process. Titanium samples were anodized with a pulsed process in a solution of silver nitrate and sodium thiosulphate at room temperature with stirring. Samples were processed with different electrolyte concentrations and treatment cycles to improve silver deposition. Physicochemical properties were determined by X-ray photoelectron spectroscopy, contact angle measurements, white-light interferometry, and scanning electron microscopy. Cellular cytotoxicity in human fibroblasts was studied with lactate dehydrogenase assays. The in vitro effect of treated surfaces on two oral bacteria strains (Streptococcus sanguinis and Lactobacillus salivarius) was studied with viable bacterial adhesion measurements and growth curve assays. Nonparametric statistical Kruskal-Wallis and Mann-Whitney U-tests were used for multiple and paired comparisons, respectively. Post hoc Spearman's correlation tests were calculated to check the dependence between bacteria adhesion and surface properties. X-ray photoelectron spectroscopy results confirmed the presence of silver on treated samples and showed that treatments with higher silver nitrate concentration and more cycles increased the silver deposition on titanium surface. No negative effects in fibroblast cell viability were detected and a significant reduction on bacterial adhesion in vitro was achieved in silver-treated samples compared with control titanium. Silver deposition on titanium with a novel electrochemical anodizing process produced surfaces with significant antibacterial properties in vitro without negative effects on cell viability. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Leukocyte-depletion of blood components does not significantly reduce the risk of infectious complications. Results of a double-blinded, randomized study

    DEFF Research Database (Denmark)

    Titlestad, I. L.; Ebbesen, L. S.; Ainsworth, A. P.

    2001-01-01

    Allogeneic blood transfusions are claimed to be an independent risk factor for postoperative infections in open colorectal surgery due to immunomodulation. Leukocyte-depletion of erythrocyte suspensions has been shown in some open randomized studies to reduce the rate of postoperative infection...

  9. Controlled lecithin release from a hierarchical architecture on blood-contacting surface to reduce hemolysis of stored red blood cells.

    Science.gov (United States)

    Shi, Qiang; Fan, Qunfu; Ye, Wei; Hou, Jianwen; Wong, Shing-Chung; Xu, Xiaodong; Yin, Jinghua

    2014-06-25

    Hemolysis of red blood cells (RBCs) caused by implant devices in vivo and nonpolyvinyl chloride containers for RBC preservation in vitro has recently gained much attention. To develop blood-contacting biomaterials with long-term antihemolysis capability, we present a facile method to construct a hydrophilic, 3D hierarchical architecture on the surface of styrene-b-(ethylene-co-butylene)-b-styrene elastomer (SEBS) with poly(ethylene oxide) (PEO)/lecithin nano/microfibers. The strategy is based on electrospinning of PEO/lecithin fibers onto the surface of poly [poly(ethylene glycol) methyl ether methacrylate] [P(PEGMEMA)]-modified SEBS, which renders SEBS suitable for RBC storage in vitro. We demonstrate that the constructed 3D architecture is composed of hydrophilic micro- and nanofibers, which transforms to hydrogel networks immediately in blood; the controlled release of lecithin is achieved by gradual dissolution of PEO/lecithin hydrogels, and the interaction of lecithin with RBCs maintains the membrane flexibility and normal RBC shape. Thus, the blood-contacting surface reduces both mechanical and oxidative damage to RBC membranes, resulting in low hemolysis of preserved RBCs. This work not only paves new way to fabricate high hemocompatible biomaterials for RBC storage in vitro, but provides basic principles to design and develop antihemolysis biomaterials for implantation in vivo.

  10. Taurolidine locks significantly reduce the incidence of catheter-related blood stream infections in high-risk patients on home parenteral nutrition.

    Science.gov (United States)

    Saunders, J; Naghibi, M; Leach, Z; Parsons, C; King, A; Smith, T; Stroud, M

    2015-02-01

    Emerging evidence suggests taurolidine reduces the risk of repeated episodes of catheter related blood stream infections (CRBSI) in a subgroup of patients receiving home parenteral nutrition (HPN). We defined 3 indications where taurolidine could be considered and retrospectively analysed data from patients who were treated over a 10 year period to examine the validity of these criteria. Twenty-two patients were identified from a total HPN population of 81, representing 33.2 years of experience. The overall CRBSI rate pre- and post-taurolidine usage was reduced from 5.71 to 0.99 infections per 1000 patient parenteral nutrition days (P-value taurolidine is used as secondary prophylaxis and providing initial data suggesting the benefit of its use as primary prophylaxis.

  11. Effects of reduced terrestrial LiDAR point density on high-resolution grain crop surface models in precision agriculture.

    Science.gov (United States)

    Hämmerle, Martin; Höfle, Bernhard

    2014-12-16

    3D geodata play an increasingly important role in precision agriculture, e.g., for modeling in-field variations of grain crop features such as height or biomass. A common data capturing method is LiDAR, which often requires expensive equipment and produces large datasets. This study contributes to the improvement of 3D geodata capturing efficiency by assessing the effect of reduced scanning resolution on crop surface models (CSMs). The analysis is based on high-end LiDAR point clouds of grain crop fields of different varieties (rye and wheat) and nitrogen fertilization stages (100%, 50%, 10%). Lower scanning resolutions are simulated by keeping every n-th laser beam with increasing step widths n. For each iteration step, high-resolution CSMs (0.01 m2 cells) are derived and assessed regarding their coverage relative to a seamless CSM derived from the original point cloud, standard deviation of elevation and mean elevation. Reducing the resolution to, e.g., 25% still leads to a coverage of >90% and a mean CSM elevation of >96% of measured crop height. CSM types (maximum elevation or 90th-percentile elevation) react differently to reduced scanning resolutions in different crops (variety, density). The results can help to assess the trade-off between CSM quality and minimum requirements regarding equipment and capturing set-up.

  12. Theoretical Analysis of the Relative Significance of Thermodynamic and Kinetic Dispersion in the dc and ac Voltammetry of Surface-Confined Molecules.

    Science.gov (United States)

    Morris, Graham P; Baker, Ruth E; Gillow, Kathryn; Davis, Jason J; Gavaghan, David J; Bond, Alan M

    2015-05-05

    Commonly, significant discrepancies are reported in theoretical and experimental comparisons of dc voltammograms derived from a monolayer or close to monolayer coverage of redox-active surface-confined molecules. For example, broader-than-predicted voltammetric wave shapes are attributed to the thermodynamic or kinetic dispersion derived from distributions in reversible potentials (E(0)) and electrode kinetics (k(0)), respectively. The recent availability of experimentally estimated distributions of E(0) and k(0) values derived from the analysis of data for small numbers of surface-confined modified azurin metalloprotein molecules now allows more realistic modeling to be undertaken, assuming the same distributions apply under conditions of high surface coverage relevant to voltammetric experiments. In this work, modeling based on conventional and stochastic kinetic theory is considered, and the computationally far more efficient conventional model is shown to be equivalent to the stochastic one when large numbers of molecules are present. Perhaps unexpectedly, when experimentally determined distributions of E(0) and k(0) are input into the model, thermodynamic dispersion is found to be unimportant and only kinetic dispersion contributes significantly to the broadening of dc voltammograms. Simulations of ac voltammetric experiments lead to the conclusion that the ac method, particularly when the analysis of kinetically very sensitive higher-order harmonics is undertaken, are far more sensitive to kinetic dispersion than the dc method. ac methods are therefore concluded to provide a potentially superior strategy for addressing the inverse problem of determining the k(0) distribution that could give rise to the apparent anomalies in surface-confined voltammetry.

  13. Theoretical Analysis of the Relative Significance of Thermodynamic and Kinetic Dispersion in the dc and ac Voltammetry of Surface-Confined Molecules

    KAUST Repository

    Morris, Graham P.

    2015-05-05

    © 2015 American Chemical Society. Commonly, significant discrepancies are reported in theoretical and experimental comparisons of dc voltammograms derived from a monolayer or close to monolayer coverage of redox-active surface-confined molecules. For example, broader-than-predicted voltammetric wave shapes are attributed to the thermodynamic or kinetic dispersion derived from distributions in reversible potentials (E0) and electrode kinetics (k0), respectively. The recent availability of experimentally estimated distributions of E0 and k0 values derived from the analysis of data for small numbers of surface-confined modified azurin metalloprotein molecules now allows more realistic modeling to be undertaken, assuming the same distributions apply under conditions of high surface coverage relevant to voltammetric experiments. In this work, modeling based on conventional and stochastic kinetic theory is considered, and the computationally far more efficient conventional model is shown to be equivalent to the stochastic one when large numbers of molecules are present. Perhaps unexpectedly, when experimentally determined distributions of E0 and k0 are input into the model, thermodynamic dispersion is found to be unimportant and only kinetic dispersion contributes significantly to the broadening of dc voltammograms. Simulations of ac voltammetric experiments lead to the conclusion that the ac method, particularly when the analysis of kinetically very sensitive higher-order harmonics is undertaken, are far more sensitive to kinetic dispersion than the dc method. ac methods are therefore concluded to provide a potentially superior strategy for addressing the inverse problem of determining the k0 distribution that could give rise to the apparent anomalies in surface-confined voltammetry.

  14. SURFACES MAGNETRON SPUTTERING REDUCES SCALE FORMATION UNDER FLOW BOILING%在流动沸腾装置中磁控溅射表面的抗垢性能

    Institute of Scientific and Technical Information of China (English)

    任晓光; 刘长厚; 等

    2001-01-01

    In this paper the effect of magnetron sputtering with DLC(diamond-like carbon),DLC-F and AC on CaSO4 scale formation was investigated. Fouling run were carried out under flow boiling conditions. The results showed that surface sputtering with DLC et. reduces CaSO4 scale formation significantly.

  15. Co-deposition of carbon dots and reduced graphene oxide nanosheets on carbon-fiber microelectrode surface for selective detection of dopamine

    Science.gov (United States)

    Fang, Jian; Xie, Zhigang; Wallace, Gordon; Wang, Xungai

    2017-08-01

    In this work, carbon dots (CD) decorated graphene oxide (GO) nanosheets were electrochemically reduced and deposited onto carbon fiber (CF) to fabricate microelectrodes for highly sensitive and selective dopamine (DA) detection, in the presence of ascorbic acid (AA) and uric acid (UA). The results have shown that surface modification considerably increases the electrocatalytic activity of the carbon fiber microelectrode. Due to possible aggregation of the rGO sheets during deposition, modifying the microelectrode surface with rGO sheets alone cannot achieve the selectivity required for simultaneous detection of DA, AA and UA. Through attaching CD onto GO sheets, the rGO + CD/CF microelectrode performance was significantly improved. The existence of CD on GO sheets can effectively avoid inter-layer stacking of the rGO sheets and provide increased surface area for neurotransmitter-electrode interaction enhancement. The CD can also increase the charge storage capacity of GO sheets. This is the first report on applying both CD and rGO for surface modification of carbon fiber microelectrode. The rGO + CD/CF microelectrode has achieved a linear DA detection concentration range of 0.1-100 μM, with a detection limit of 0.02 μM. The sensitivity of the microelectrode towards DA was as high as 6.5 nA/μM, which is significantly higher than previously reported carbon fiber microelectrodes. The highly sensitive all-carbon based microelectrodes should find use in a number of biomedical applications, such as neurotransmitter detection, neural signal recording and cell physiology studies.

  16. Alpha-1 proteinase inhibitor M358R reduces thrombin generation when displayed on the surface of cells expressing tissue factor.

    Science.gov (United States)

    Gierczak, Richard F; Pepler, Laura; Bhagirath, Vinai; Liaw, Patricia C; Sheffield, William P

    2014-11-01

    The M358R variant of alpha-1-proteinase inhibitor (API) is a potent soluble inhibitor of thrombin. Previously we engineered AR-API M358R, a membrane-bound form of this protein and showed that it inhibited exogenous thrombin when expressed on transfected cells lacking tissue factor (TF). To determine the suitability of AR-API M358R for gene transfer to vascular cells to limit thrombogenicity, we tested the ability of AR-API M358R to inhibit endogenous thrombin generated in plasma via co-expression co-expressing it on the surface of cells expressing TF. Transfected AR-API M358R formed inhibitory complexes with thrombin following exposure of recalcified, defibrinated plasma to TF on T24/83 cells, but discontinuously monitored thrombin generation was unaffected. Similarly, AR-API M358R expression did not reduce continuously monitored thrombin generation by T24/83 cell suspensions exposed to recalcified normal plasma in a Thrombogram-Thrombinoscope-type thrombin generation assay (TGA); in contrast, 1 μM hirudin variant 3 or soluble API M358R abolished thrombin generation. Gene transfer of TF to HEK 293 conferred the ability to support TF-dependent thrombin generation on HEK 293 cells. Co-transfection of HEK 293 cells with a 9:1 excess of DNA encoding AR-API M358R to that encoding TF reduced peak thrombin generation approximately 3-fold compared to controls. These in vitro results suggest that surface display of API M358R inhibits thrombin generation when the tethered serpin is expressed in excess of TF, and suggest its potential to limit thrombosis in appropriate vascular beds in animal models.

  17. The immediate effectiveness of barley straw mulch in reducing soil erodibility and surface runoff generation in Mediterranean vineyards.

    Science.gov (United States)

    Prosdocimi, Massimo; Jordán, Antonio; Tarolli, Paolo; Keesstra, Saskia; Novara, Agata; Cerdà, Artemi

    2016-03-15

    Soil and water loss in agriculture is a major problem throughout the world, and especially in Mediterranean areas. Non-conservation agricultural practices have further aggravated the situation, especially in vineyards, which are affected by one of the highest rates of soil loss among cultivated lands. Therefore, it is necessary to find the right soil practices for more sustainable viticulture. In this regard, straw mulching has proven to be effective in other crop and fire affected soils, but, nonetheless, little research has been carried out in vineyards. This research tests the effect of barley straw mulching on soil erosion and surface runoff on vineyards in Eastern Spain where the soil and water losses are non-sustainable. An experiment was setup using rainfall simulation tests at 55 mm h(-1) over 1h on forty paired plots of 0.24 m(2): twenty bare and twenty straw covered. Straw cover varied from 48 to 90% with a median value of 59% as a result of the application of 75 g of straw per m(2). The use of straw mulch resulted in delayed ponding and runoff generation and, as a consequence, the median water loss decreased from 52.59 to 39.27% of the total rainfall. The straw cover reduced the median sediment concentration in runoff from 9.8 to 3.0 g L(-1) and the median total sediment detached from 70.34 to 15.62 g per experiment. The median soil erosion rate decreased from 2.81 to 0.63 Mg ha(-1)h(-1) due to the straw mulch protection. Straw mulch is very effective in reducing soil erodibility and surface runoff, and this benefit was achieved immediately after the application of the straw.

  18. Molecular characterization of sulfate-reducing bacteria community in surface sediments from the adjacent area of Changjiang Estuary

    Science.gov (United States)

    Zhang, Yu; Zhen, Yu; Mi, Tiezhu; He, Hui; Yu, Zhigang

    2016-02-01

    Sulfate-reducing bacteria (SRB), which obtain energy from dissimilatory sulfate reduction, play a vital role in the carbon and sulfur cycles. The dissimilatory sulfite reductase (Dsr), catalyzing the last step in the sulfate reduction pathway, has been found in all known SRB that have been tested so far. In this study, the diversity of SRB was investigated in the surface sediments from the adjacent area of Changjiang Estuary by PCR amplification, cloning and sequencing of the dissimilatory sulfite reductase beta subunit gene ( dsrB). Based on dsrB clone libraries constructed in this study, diversified SRB were found, represented by 173 unique OTUs. Certain cloned sequences were associated with Desulfobacteraceae, Desulfobulbaceae, and a large fraction (60%) of novel sequences that have deeply branched groups in the dsrB tree, indicating that novel SRB inhabit the surface sediments. In addition, correlations of the SRB assemblages with environmental factors were analyzed by the linear model-based redundancy analysis (RDA). The result revealed that temperature, salinity and the content of TOC were most closely correlated with the SRB communities. More information on SRB community was obtained by applying the utility of UniFrac to published dsrB gene sequences from this study and other 9 different kinds of marine environments. The results demonstrated that there were highly similar SRB genotypes in the marine and estuarine sediments, and that geographic positions and environmental factors influenced the SRB community distribution.

  19. An AlGaN/GaN HEMT with a reduced surface electric field and an improved breakdown voltage

    Institute of Scientific and Technical Information of China (English)

    Xie Gang; Edward Xu; Niloufar Hashemi; Zhang Bo; Fred Y. Fu; Wai Tung Ng

    2012-01-01

    A reduced surface electric field in an AlGaN/GaN high electron mobility transistor (HEMT) is investigated by employing a localized Mg-doped layer under the two-dimensional electron gas (2-DEG) channel as an electric field shaping layer.The electric field strength around the gate edge is effectively relieved and the surface electric field is distributed evenly as compared with those of HEMTs with conventional source-connected field plate and double field plate structures with the same device physical dimensions.Compared with the HEMTs with conventional sourceconnected field plates and double field plates,the HEMT with a Mg-doped layer also shows that the breakdown location shifts from the surface of the gate edge to the bulk Mg-doped layer edge.By optimizing both the length of Mg-doped layer,Lm,and the doping concentration,a 5.5 times and 3 times the reduction in the peak electric field near the drain side gate edge is observed as compared with those of the HEMTs with source-connected field plate structure and double field plate structure,respectively.In a device with VGS =-5 V,Lm =1.5 μm,a peak Mg doping concentration of 8×1017 cm-3 and a drift region length of 10 μm,the breakdown voltage is observed to increase from 560 V in a conventional device without field plate structure to over 900 V without any area overhead penalty.

  20. Application of variational reduced-density-matrix theory to the potential energy surfaces of the nitrogen and carbon dimers.

    Science.gov (United States)

    Gidofalvi, Gergely; Mazziotti, David A

    2005-05-15

    The acceleration of the variational two-electron reduced-density-matrix (2-RDM) method, using a new first-order algorithm [D. A. Mazziotti, Phys. Rev. Lett. 93, 213001 (2004)], has shown its usefulness in the accurate description of potential energy surfaces in nontrivial basis sets. Here we apply the first-order 2-RDM method to the potential energy surfaces of the nitrogen and carbon dimers in polarized valence double-zeta basis sets for which benchmark full-configuration-interaction calculations exist. In a wave function formalism accurately stretching the triple bond of the nitrogen dimer requires at least six-particle excitations from the Hartree-Fock reference. Furthermore, cleaving the double bond of C2 should produce a "non-Morse"-like potential curve because the ground state near equilibrium (X 1sigma(g)+) has an avoided crossing with the second excited state (B' 1sigma(g)+) and a level crossing with the first excited state (B 1delta(g)). Because the 2-RDM method variationally optimizes the energy over correlated 2-RDMs on the two-electron space without parametrization of the many-electron wave function, it captures multireference correlations that are difficult to describe with approximate wave functions. The 2-RDM method yields for N2 a potential energy surface with features and spectroscopic constants that are more accurate than those from single-reference methods and similar in accuracy to multireference techniques, and it describes the non-Morse-like behavior of C2 which is not captured by single-reference methods.

  1. Compositional Similarities and Differences between Transparent Exopolymer Particles (TEP) from two Marine Bacteria and two Marine Algae: Significance to Surface Biofouling

    KAUST Repository

    Li, Sheng

    2015-06-12

    Transparent-exopolymer-particles (TEP) have been recently identified as a significant contributor to surface biofouling, such as on reverse osmosis (RO) membranes. TEP research has mainly focused on algal TEP/TEP precursors while limited investigations have been conducted on those released by bacteria. In this study, TEP/TEP precursors derived from both algae and bacteria were isolated and then characterized to investigate their similarities and/or differences using various advanced analytical techniques, thus providing a better understanding of their potential effect on biofouling. Bacterial TEP/TEP precursors were isolated from two species of marine bacteria (Pseudidiomarina homiensis and Pseudoalteromonas atlantica) while algal TEP/TEP precursors were isolated from two marine algae species (Alexandrium tamarense and Chaetoceros affinis). Results indicated that both isolated bacterial and algal TEP/TEP precursors were associated with protein-like materials, and most TEP precursors were high-molecular-weight biopolymers. Furthermore all investigated algal and bacterial TEP/TEP precursors showed a lectin-like property, which can enable them to act as a chemical conditioning layer and to agglutinate bacteria. This property may enhance surface biofouling. However, both proton nuclear magnetic resonance (NMR) spectra and the nitrogen/carbon (N/C) ratios suggested that the algal TEP/TEP precursors contained much less protein content than the bacterial TEP/TEP precursors. This difference may influence their initial deposition and further development of surface biofouling.

  2. Reduced Time CT Perfusion Acquisitions Are Sufficient to Measure the Permeability Surface Area Product with a Deconvolution Method

    Directory of Open Access Journals (Sweden)

    Francesco Giuseppe Mazzei

    2014-01-01

    Full Text Available Objective. To reduce the radiation dose, reduced time CT perfusion (CTp acquisitions are tested to measure permeability surface (PS with a deconvolution method. Methods and Materials. PS was calculated with repeated measurements (n=305 while truncating the time density curve (TDC at different time values in 14 CTp studies using CTp 4D software (GE Healthcare, Milwaukee, WI, US. The median acquisition time of CTp studies was 59.35 sec (range 49–92 seconds. To verify the accuracy of the deconvolution algorithm, a variation of the truncated PS within the error measurements was searched, that is, within 3 standard deviations from the mean nominal error provided by the software. The test was also performed for all the remaining CTp parameters measured. Results. PS maximum variability happened within 25 seconds. The PS became constant after 40 seconds for the majority of the active tumors (10/11, while for necrotic tissues it was consistent within 1% after 50 seconds. A consistent result lasted for all the observed CTp parameters, as expected from their analytical dependance. Conclusion. 40-second acquisition time could be an optimal compromise to obtain an accurate measurement of the PS and a reasonable dose exposure with a deconvolution method.

  3. Acquiring a pet dog significantly reduces stress of primary carers for children with autism spectrum disorder: a prospective case control study

    OpenAIRE

    Wright, H. F.; Hall, S; Hames, A.; Hardiman, J; Mills, R.; ,; Mills, D. S.

    2015-01-01

    This study describes the impact of pet dogs on stress of primary carers of children with Autism Spectrum Disorder (ASD). Stress levels of 38 primary carers acquiring a dog and 24 controls not acquiring a dog were sampled at: Pre-intervention (17 weeks before acquiring a dog), post-intervention (3–10 weeks after acquisition) and follow-up (25–40 weeks after acquisition), using the Parenting Stress Index. Analysis revealed significant improvements in the intervention compared to the control gro...

  4. Putative floral brood-site mimicry, loss of autonomous selfing, and reduced vegetative growth are significantly correlated with increased diversification in Asarum (Aristolochiaceae).

    Science.gov (United States)

    Sinn, Brandon T; Kelly, Lawrence M; Freudenstein, John V

    2015-08-01

    The drivers of angiosperm diversity have long been sought and the flower-arthropod association has often been invoked as the most powerful driver of the angiosperm radiation. We now know that features that influence arthropod interactions cannot only affect the diversification of lineages, but also expedite or constrain their rate of extinction, which can equally influence the observed asymmetric richness of extant angiosperm lineages. The genus Asarum (Aristolochiaceae; ∼100 species) is widely distributed in north temperate forests, with substantial vegetative and floral divergence between its three major clades, Euasarum, Geotaenium, and Heterotropa. We used Binary-State Speciation and Extinction Model (BiSSE) Net Diversification tests of character state distributions on a Maximum Likelihood phylogram and a Coalescent Bayesian species tree, inferred from seven chloroplast markers and nuclear rDNA, to test for signal of asymmetric diversification, character state transition, and extinction rates of floral and vegetative characters. We found that reduction in vegetative growth, loss of autonomous self-pollination, and the presence of putative fungal-mimicking floral structures are significantly correlated with increased diversification in Asarum. No significant difference in model likelihood was identified between symmetric and asymmetric rates of character state transitions or extinction. We conclude that the flowers of the Heterotropa clade may have converged on some aspects of basidiomycete sporocarp morphology and that brood-site mimicry, coupled with a reduction in vegetative growth and the loss of autonomous self-pollination, may have driven diversification within Asarum. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Methodology to predict a maximum follow-up period for breast cancer patients without significantly reducing the chance of detecting a local recurrence

    Science.gov (United States)

    Mould, Richard F.; Asselain, Bernard; DeRycke, Yann

    2004-03-01

    For breast cancer where the prognosis of early stage disease is very good and even when local recurrences do occur they can present several years after treatment, the hospital resources required for annual follow-up examinations of what can be several hundreds of patients are financially significant. If, therefore, there is some method to estimate a maximum length of follow-up Tmax necessary, then cost savings of physicians' time as well as outpatient workload reductions can be achieved. In modern oncology where expenses continue to increase exponentially due to staff salaries and the expense of chemotherapy drugs and of new treatment and imaging technology, the economic situation can no longer be ignored. The methodology of parametric modelling, based on the lognormal distribution is described, showing that useful estimates for Tmax can be made, by making a trade-off between Tmax and the fraction of patients who will experience a delay in detection of their local recurrence. This trade-off depends on the chosen tail of the lognormal. The methodology is described for stage T1 and T2 breast cancer and it is found that Tmax = 4 years which is a significant reduction on the usual maximum of 10 years of follow-up which is employed by many hospitals for breast cancer patients. The methodology is equally applicable for cancers at other sites where the prognosis is good and some local recurrences may not occur until several years post-treatment.

  6. Varying protein source and quantity do not significantly improve weight loss, fat loss, or satiety in reduced energy diets among midlife adults.

    Science.gov (United States)

    Aldrich, Noel D; Reicks, Marla M; Sibley, Shalamar D; Redmon, J Bruce; Thomas, William; Raatz, Susan K

    2011-02-01

    We hypothesized that a whey protein diet would result in greater weight loss and improved body composition compared with standard weight loss diets. Weight change, body composition, and renin-angiotensin aldosterone system activity in midlife adults were compared between diet groups. Eighteen subjects enrolled in a 5-month study of 8-week controlled food intake followed by 12-weeks ad libitum intake. Subjects were randomized to 1 of 3 treatment groups: control diet (CD) (55% carbohydrate/15% protein/30% fat), mixed protein (40% carbohydrate/30% protein/30% fat), or whey protein (WP) (40% carbohydrate/15% mixed protein/15% whey protein/30% fat). Measurements included weight, metabolic measures, body composition by dual-energy x-ray absorptiometry, and resting energy expenditure. No statistically significant differences in total weight loss or total fat loss were observed between treatments; however, a trend toward greater total weight loss (P = .08) and total fat loss (P = .09) was observed in the WP group compared with the CD group. Fat loss in the leg and gynoid regions was greater (P loss or in total fat loss, but significant differences in regional fat loss and in decreased blood pressure were observed in the WP group. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Targeting CXCR1/2 Significantly Reduces Breast Cancer Stem Cell Activity and Increases the Efficacy of Inhibiting HER2 via HER2-dependent and -independent Mechanisms

    Science.gov (United States)

    Singh, Jagdeep K.; Farnie, Gillian; Bundred, Nigel J.; Simões, Bruno M; Shergill, Amrita; Landberg, Göran; Howell, Sacha; Clarke, Robert B.

    2012-01-01

    Purpose Breast cancer stem-like cells (CSCs) are an important therapeutic target as they are predicted to be responsible for tumour initiation, maintenance and metastases. Interleukin-8 (IL-8) is upregulated in breast cancer and associated with poor prognosis. Breast cancer cell line studies indicate that IL-8 via its cognate receptors, CXCR1 and CXCR2, is important in regulating breast CSC activity. We investigated the role of IL-8 in the regulation of CSC activity using patient-derived breast cancers and determined the potential benefit of combining CXCR1/2 inhibition with HER2-targeted therapy. Experimental design CSC activity of metastatic and invasive human breast cancers (n=19) was assessed ex vivo using the mammosphere colony forming assay. Results Metastatic fluid IL-8 level correlated directly with mammosphere formation (r=0.652; P<0.05; n=10). Recombinant IL-8 directly increased mammosphere formation/self-renewal in metastatic and invasive breast cancers (n=17). IL-8 induced activation of EGFR/HER2 and downstream signalling pathways and effects were abrogated by inhibition of SRC, EGFR/HER2, PI3K or MEK. Furthermore, lapatinib inhibited the mammosphere-promoting effect of IL-8 in both HER2-positive and negative patient-derived cancers. CXCR1/2 inhibition also blocked the effect of IL-8 on mammosphere formation and added to the efficacy of lapatinib in HER2-positive cancers. Conclusions These studies establish a role for IL-8 in the regulation of patient-derived breast CSC activity and demonstrate that IL-8/CXCR1/2 signalling is partly mediated via a novel SRC and EGFR/HER2-dependent pathway. Combining CXCR1/2 inhibitors with current HER2-targeted therapies has potential as an effective therapeutic strategy to reduce CSC activity in breast cancer and improve the survival of HER2-positive patients. PMID:23149820

  8. The success of {sup 131}I ablation in thyroid cancer patients is significantly reduced after a diagnostic activity of 40 MBq {sup 131}I

    Energy Technology Data Exchange (ETDEWEB)

    Verburg, F.A. [Dept. of Nuclear Medicine, Univ. Medical Center Utrecht (Netherlands); Dept. of Nuclear Medicine, Univ. Hospital Wuerzburg (Germany); Verkooijen, R.B.T. [Div. of Nuclear Medicine, Dept. of Radiology, Leiden Univ. Medical Center (Netherlands); Dept. of Nuclear Medicine, Maxima Medical Centre (Netherlands); Stokkel, M.P.M. [Div. of Nuclear Medicine, Dept. of Radiology, Leiden Univ. Medical Center (Netherlands); Isselt, J.W. van [Dept. of Nuclear Medicine, Univ. Medical Center Utrecht (Netherlands)

    2009-07-01

    Objective: Dosimetry studies have shown that activities of {sup 131}I as small as 10-20 MBq may cause a stunning effect. A result of this stunning effect may be a lower success rate of the ablative {sup 131}I therapy for differentiated thyroid carcinoma (DTC). The aim of this study was to determine whether pre-therapeutic uptake measurement with 40 MBq {sup 131}I causes a lower success rate of ablation. Design: retrospective chart review study. Patients, methods: In two hospitals the ablation protocols differed in one respect only: in the one hospital no diagnostic {sup 131}I was applied before ablation (group 1, n = 48), whereas in the other hospital a 24-h uptake-measurement with 40 MBq {sup 131}I was performed (group 2, n = 51). Included were all DTC patients without distant metastases who had undergone {sup 131}I ablation between July 2002 and December 2005, and who had returned for {sup 131}I follow-up. Successful ablation was defined as absence of pathological {sup 131}I uptake on diagnostic whole-body scintigraphy and undetectable thyroglobulin-levels under TSH stimulation. Results: Overall, ablation was successful in 31/48 patients (65%) in group 1 and in 17/51 patients (33%) in group 2 (p=0.002). Multivariate analysis showed that pre-therapeutic uptake measurement using 40 MBq {sup 131}I was an independant determinant for success of ablation (p = 0.002). Conclusions: After applying a diagnostic activity of 40 MBq {sup 131}I before ablation, the success rate of ablation is severely reduced. Consequently, the routine application of {sup 131}I for diagnostic scintigraphy or uptake measurement prior to {sup 131}I ablation is best avoided. (orig.)

  9. Human Tubal-Derived Mesenchymal Stromal Cells Associated with Low Level Laser Therapy Significantly Reduces Cigarette Smoke-Induced COPD in C57BL/6 mice.

    Directory of Open Access Journals (Sweden)

    Jean Pierre Schatzmann Peron

    Full Text Available Cigarette smoke-induced chronic obstructive pulmonary disease is a very debilitating disease, with a very high prevalence worldwide, which results in a expressive economic and social burden. Therefore, new therapeutic approaches to treat these patients are of unquestionable relevance. The use of mesenchymal stromal cells (MSCs is an innovative and yet accessible approach for pulmonary acute and chronic diseases, mainly due to its important immunoregulatory, anti-fibrogenic, anti-apoptotic and pro-angiogenic. Besides, the use of adjuvant therapies, whose aim is to boost or synergize with their function should be tested. Low level laser (LLL therapy is a relatively new and promising approach, with very low cost, no invasiveness and no side effects. Here, we aimed to study the effectiveness of human tube derived MSCs (htMSCs cell therapy associated with a 30mW/3J-660 nm LLL irradiation in experimental cigarette smoke-induced chronic obstructive pulmonary disease. Thus, C57BL/6 mice were exposed to cigarette smoke for 75 days (twice a day and all experiments were performed on day 76. Experimental groups receive htMSCS either intraperitoneally or intranasally and/or LLL irradiation either alone or in association. We show that co-therapy greatly reduces lung inflammation, lowering the cellular infiltrate and pro-inflammatory cytokine secretion (IL-1β, IL-6, TNF-α and KC, which were followed by decreased mucus production, collagen accumulation and tissue damage. These findings seemed to be secondary to the reduction of both NF-κB and NF-AT activation in lung tissues with a concomitant increase in IL-10. In summary, our data suggests that the concomitant use of MSCs + LLLT may be a promising therapeutic approach for lung inflammatory diseases as COPD.

  10. Reduced near-surface thermal inversions in 2005-06 in the southeastern Arabian Sea (Lakshadweep Sea)

    Digital Repository Service at National Institute of Oceanography (India)

    Nisha, K.; Rao, S.A.; Gopalakrishna, V.V.; Rao, R.R.; GirishKumar, M.S.; Pankajakshan, T.; Ravichandran, M.; Rajesh, S.; Girish, K.; Johnson, Z.; Anuradha, M.; Gavaskar, S.S.M.; Suneel, V.; Krishna, S.M.

    relatively cooler near-surface thermal regime persisted owing to prolonged upwelling until November 2005. In addition, the observed local surface wind field was relatively stronger, and the net surface heat gain to the ocean was weaker over the Lakshadweep...

  11. A Cationic [60] Fullerene Derivative Reduces Invasion and Migration of HT-29 CRC Cells in Vitro at Dose Free of Significant Effects on Cell Survival

    Institute of Scientific and Technical Information of China (English)

    Marianna Lucafo; Chiara Pelillo; Marco Carini; Tatiana Da Ros; Maurizio Prato; Gianni Sava

    2014-01-01

    Nanomaterials with unique characteristics exhibit favorable therapeutic and diagnostic properties, implying their enormous potential as biomedical candidates. C60 has been used in gene- and drug-delivery, as imaging agents, and as photosensitizers in cancer therapy. In this study, the influences of a cationic function-alized fullerene on cellular behavior of human colorectal cancer cell line (HT-29) were investigated. Results indicated that HT-29 treated with the studied compound showed a lower sensitivity but a significant impair-ment in migration and invasion by interfering with the activities of matrix metalloproteinases (MMP-2 and 9). The presence of fullerene also altered the capacity of adhesion-related proteins to perform their activity, thereby inducing dramatically adverse effects on the cell physiological functions such as cell adhesion. Thus, our study suggests that this compound is a new potential anti-metastatic effector and a therapeutic component for malignant colorectal cancer.

  12. Citric acid modifies surface properties of commercial CeO{sub 2} nanoparticles reducing their toxicity and cerium uptake in radish (Raphanus sativus) seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Trujillo-Reyes, J. [Chemistry Department, The University of Texas at El Paso, 500 West University Av., El Paso, TX 79968 (United States); Vilchis-Nestor, A.R. [Centro Conjunto de Investigación en Química Sustentable UAEM—UNAM, Carretera Toluca—Atlacomulco km 14.5, San Cayetano, CP 50200 Toluca, Estado de México (Mexico); Majumdar, S. [Chemistry Department, The University of Texas at El Paso, 500 West University Av., El Paso, TX 79968 (United States); University of California Center for Environmental Implications of Nanotechnology (UC CEIN), The University of Texas at El Paso, 500 West University Av., El Paso, TX 79968 (United States); Peralta-Videa, J.R. [Chemistry Department, The University of Texas at El Paso, 500 West University Av., El Paso, TX 79968 (United States); Environmental Science and Engineering PhD program, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968 (United States); University of California Center for Environmental Implications of Nanotechnology (UC CEIN), The University of Texas at El Paso, 500 West University Av., El Paso, TX 79968 (United States); Gardea-Torresdey, J.L., E-mail: jgardea@utep.edu [Chemistry Department, The University of Texas at El Paso, 500 West University Av., El Paso, TX 79968 (United States); Environmental Science and Engineering PhD program, The University of Texas at El Paso, 500 West University Ave., El Paso, TX 79968 (United States); University of California Center for Environmental Implications of Nanotechnology (UC CEIN), The University of Texas at El Paso, 500 West University Av., El Paso, TX 79968 (United States)

    2013-12-15

    Highlights: • The citric acid capping significantly reduced the ζ potential values. • As the amount of CA increased, thicker the layer surrounding the CeO{sub 2} NPs. • CeO{sub 2}/CA NPs had better distribution and small particle size than bare CeO{sub 2} NPs. • CeO{sub 2}/CA NPs decrease the Ce uptake by radish seedlings. -- Abstract: Little is known about the mobility, reactivity, and toxicity to plants of coated engineered nanoparticles (ENPs). Surface modification may change the interaction of ENPs with living organisms. This report describes surface changes in commercial CeO{sub 2} NPs coated with citric acid (CA) at molar ratios of 1:2, 1:3, 1:7, and 1:10 CeO{sub 2}:CA, and their effects on radish (Raphanus sativus) seed germination, cerium and nutrients uptake. All CeO{sub 2} NPs and their absorption by radish plants were characterized by TEM, DLS, and ICP-OES. Radish seeds were germinated in pristine and CA coated CeO{sub 2} NPs suspensions at 50 mg/L, 100 mg/L, and 200 mg/L. Deionized water and CA at 100 mg/L were used as controls. Results showed ζ potential values of 21.6 mV and −56 mV for the pristine and CA coated CeO{sub 2} NPs, respectively. TEM images showed denser layers surrounding the CeO{sub 2} NPs at higher CA concentrations, as well as better distribution and smaller particle sizes. None of the treatments affected seed germination. However, at 200 mg/L the CA coated NPs at 1:7 ratio produced significantly (p ≤ 0.05) more root biomass, increased water content and reduced by 94% the Ce uptake, compared to bare NPs. This suggests that CA coating decrease CeO{sub 2} NPs toxicity to plants.

  13. Absorption and distribution characteristics of 5-fluorouracil (5-FU) after an application to the liver surface in rats in order to reduce systemic side effects.

    Science.gov (United States)

    Kodama, Yukinobu; Fumoto, Shintaro; Nishi, Junya; Nakashima, Mikiro; Sasaki, Hitoshi; Nakamura, Junzo; Nishida, Koyo

    2008-05-01

    The present study was undertaken to elucidate the absorption and distribution characteristics of 5-fluorouracil (5-FU) after its application to the liver surface in rats to examine the possibility of reducing the systemic side effects of this agent. 5-FU was applied to the surface of the liver by employing a cylindrical diffusion cell. Approximately 69% of the dose was absorbed in 360 min. The time course of the change in the amount of 5-FU remaining in the diffusion cell obeyed first-order kinetics. Also, a linear relationship was observed between the apparent permeability coefficient, P app, and the reciprocal of the square root of the molecular weight of several compounds including 5-FU. The estimated P app value of 5-FU was in good agreement with the experimental value. The plasma concentration of 5-FU was low (5-FU was rapidly eliminated from the plasma and could not be detected at 120 min. In the analysis of tissue distribution, the liver was divided into three sites; the region under the diffusion cell attachment site (site 1), the treated lobe excluding site 1 (site 2), and untreated lobes (site 3). After being administered i.v., 5-FU mainly distributed in the kidney, and the concentration in the liver was significantly lower than that in kidney, spleen, or heart. After its application to the liver surface, however, 5-FU preferentially distributed at site 1, and was not detected at the other sites or in other tissues. Thus, these results suggested the possibility of a reduction in the systemic side effect of 5-FU on its application to the liver surface.

  14. Surface-Displayed IL-10 by Recombinant Lactobacillus plantarum Reduces Th1 Responses of RAW264.7 Cells Stimulated with Poly(I:C) or LPS.

    Science.gov (United States)

    Cai, Ruopeng; Jiang, Yanlong; Yang, Wei; Yang, Wentao; Shi, Shaohua; Shi, Chunwei; Hu, Jingtao; Gu, Wei; Ye, Liping; Zhou, Fangyu; Gong, Qinglong; Han, Wenyu; Yang, Guilian; Wang, Chunfeng

    2016-02-01

    Recently, poly-γ-glutamic acid synthetase A (pgsA) has been applied to display exogenous proteins on the surface of Lactobacillus casei or Lactococcus lactis, which results in a surfacedisplayed component of bacteria. However, the ability of carrying genes encoded by plasmids and the expression efficiency of recombinant bacteria can be somewhat affected by the longer gene length of pgsA (1,143 bp); therefore, a truncated gene, pgsA, was generated based on the characteristics of pgsA by computational analysis. Using murine IL-10 as an exogenous gene, recombinant Lactobacillus plantarum was constructed and the capacity of the surface-displayed protein and functional differences between exogenous proteins expressed by these strains were evaluated. Surface expression of IL-10 on both recombinant bacteria with anchorins and the higher expression levels in L. plantarum-pgsA'-IL-10 were confirmed by western blot assay. Most importantly, up-regulation of IL-1β, IL-6, TNF-α, IFN-γ, and the nuclear transcription factor NF-κB p65 in RAW264.7 cells after stimulation with Poly(I:C) or LPS was exacerbated after co-culture with L. plantarum-pgsA. By contrast, IL-10 expressed by these recombinant strains could reduce these factors, and the expression of these factors was associated with recombinant strains that expressed anchorin (especially in L. plantarum-pgsA'-IL-10) and was significantly lower compared with the anchorin-free strains. These findings indicated that exogenous proteins could be successfully displayed on the surface of L. plantarum by pgsA or pgsA', and the expression of recombinant bacteria with pgsA' was superior compared with bacteria with pgsA.

  15. Comparison of the carbon isotope composition of total organic carbon and long-chain n-alkanes from surface soils in eastern China and their significance

    Institute of Scientific and Technical Information of China (English)

    RAO ZhiGuo; JIA GuoDong; ZHU ZhaoYu; WU Yi; ZHANG JiaWu

    2008-01-01

    Surface soil samples collected over a high spatial resolution in eastern China were analyzed for carbon isotope composition (δ13C) of total organic carbon (TOC) and higher plant-derived long-chain n-alkanes,with the latter reported as weighted mean values. The two sets of δ13C values are significantly correlated and show similar trends in spatial variation. The spatial distribution of δ13C shows less negative values in the mid-latitudes between 31°N and 40°N and more negative ones at higher and lower latitudes. This is consistent with previously reported carbon isotope data from surface soil phytoliths in the same region and suggests that the mid-latitude area provides relatively favorable growing conditions for C4 plants. Furthermore, δ13C values of both TOC and long-chain n-alkanes from 12 surface soil samples collected from a small grassland in north China displayed similar carbon isotope values and the difference between paired δ13C of a soil samples remains relatively constant. Our data demonstrate that in eastern China, soil δ13C composition of both TOC and long-chain n-alkanes is effective indicators of Ca/C4 ratios of the prevailing vegetation. This work suggests that -22‰ and -32‰ are good estimated end members for the weighted mean δ13C values of long-chain n-alkanes (C27, C29 and C31 n-alkanes) from soils under dominant C4 or C3 vegetation, allowing us to reconstruct paleovegetation trends.

  16. A Yersinia pestis-specific, lytic phage preparation significantly reduces viable Y. pestis on various hard surfaces experimentally contaminated with the bacterium

    OpenAIRE

    Rashid, Mohammed H.; Revazishvili, Tamara; Dean, Timothy; Butani, Amy; Verratti, Kathleen; Bishop-Lilly, Kimberly A.; Sozhamannan, Shanmuga; Sulakvelidze, Alexander; Rajanna, Chythanya

    2012-01-01

    Five Y. pestis bacteriophages obtained from various sources were characterized to determine their biological properties, including their taxonomic classification, host range and genomic diversity. Four of the phages (YpP-G, Y, R and YpsP-G) belong to the Podoviridae family, and the fifth phage (YpsP-PST) belongs to the Myoviridae family, of the order Caudovirales comprising of double-stranded DNA phages. The genomes of the four Podoviridae phages were fully sequenced and found to be almost id...

  17. Development of highly faceted reduced graphene oxide-coated copper oxide and copper nanoparticles on a copper foil surface

    Directory of Open Access Journals (Sweden)

    Rebeca Ortega-Amaya

    2016-07-01

    Full Text Available This work describes the formation of reduced graphene oxide-coated copper oxide and copper nanoparticles (rGO-Cu2ONPs, rGO-CuNPs on the surface of a copper foil supporting graphene oxide (GO at annealing temperatures of 200–1000 °C, under an Ar atmosphere. These hybrid nanostructures were developed from bare copper oxide nanoparticles which grew at an annealing temperature of 80 °C under nitrogen flux. The predominant phase as well as the particle size and shape strongly depend on the process temperature. Characterization with transmission electron microscopy and scanning electron microscopy indicates that Cu or Cu2O nanoparticles take rGO sheets from the rGO network to form core–shell Cu–rGO or Cu2O–rGO nanostructures. It is noted that such ones increase in size from 5 to 800 nm as the annealing temperature increases in the 200–1000 °C range. At 1000 °C, Cu nanoparticles develop a highly faceted morphology, displaying arm-like carbon nanorods that originate from different facets of the copper crystal structure.

  18. Colonization on root surface by a phenanthrene-degrading endophytic bacterium and its application for reducing plant phenanthrene contamination.

    Directory of Open Access Journals (Sweden)

    Juan Liu

    Full Text Available A phenanthrene-degrading endophytic bacterium, Pn2, was isolated from Alopecurus aequalis Sobol grown in soils contaminated with polycyclic aromatic hydrocarbons (PAHs. Based on morphology, physiological characteristics and the 16S rRNA gene sequence, it was identified as Massilia sp. Strain Pn2 could degrade more than 95% of the phenanthrene (150 mg · L(-1 in a minimal salts medium (MSM within 48 hours at an initial pH of 7.0 and a temperature of 30 °C. Pn2 could grow well on the MSM plates with a series of other PAHs, including naphthalene, acenaphthene, anthracene and pyrene, and degrade them to different degrees. Pn2 could also colonize the root surface of ryegrass (Lolium multiflorum Lam, invade its internal root tissues and translocate into the plant shoot. When treated with the endophyte Pn2 under hydroponic growth conditions with 2 mg · L(-1 of phenanthrene in the Hoagland solution, the phenanthrene concentrations in ryegrass roots and shoots were reduced by 54% and 57%, respectively, compared with the endophyte-free treatment. Strain Pn2 could be a novel and useful bacterial resource for eliminating plant PAH contamination in polluted environments by degrading the PAHs inside plants. Furthermore, we provide new perspectives on the control of the plant uptake of PAHs via endophytic bacteria.

  19. Development of highly faceted reduced graphene oxide-coated copper oxide and copper nanoparticles on a copper foil surface

    Science.gov (United States)

    Matsumoto, Yasuhiro; Espinoza-Rivas, Andrés M; Pérez-Guzmán, Manuel A; Ortega-López, Mauricio

    2016-01-01

    Summary This work describes the formation of reduced graphene oxide-coated copper oxide and copper nanoparticles (rGO-Cu2ONPs, rGO-CuNPs) on the surface of a copper foil supporting graphene oxide (GO) at annealing temperatures of 200–1000 °C, under an Ar atmosphere. These hybrid nanostructures were developed from bare copper oxide nanoparticles which grew at an annealing temperature of 80 °C under nitrogen flux. The predominant phase as well as the particle size and shape strongly depend on the process temperature. Characterization with transmission electron microscopy and scanning electron microscopy indicates that Cu or Cu2O nanoparticles take rGO sheets from the rGO network to form core–shell Cu–rGO or Cu2O–rGO nanostructures. It is noted that such ones increase in size from 5 to 800 nm as the annealing temperature increases in the 200–1000 °C range. At 1000 °C, Cu nanoparticles develop a highly faceted morphology, displaying arm-like carbon nanorods that originate from different facets of the copper crystal structure. PMID:27547618

  20. Citric acid modifies surface properties of commercial CeO2 nanoparticles reducing their toxicity and cerium uptake in radish (Raphanus sativus) seedlings.

    Science.gov (United States)

    Trujillo-Reyes, J; Vilchis-Nestor, A R; Majumdar, S; Peralta-Videa, J R; Gardea-Torresdey, J L

    2013-12-15

    Little is known about the mobility, reactivity, and toxicity to plants of coated engineered nanoparticles (ENPs). Surface modification may change the interaction of ENPs with living organisms. This report describes surface changes in commercial CeO2 NPs coated with citric acid (CA) at molar ratios of 1:2, 1:3, 1:7, and 1:10 CeO2:CA, and their effects on radish (Raphanus sativus) seed germination, cerium and nutrients uptake. All CeO2 NPs and their absorption by radish plants were characterized by TEM, DLS, and ICP-OES. Radish seeds were germinated in pristine and CA coated CeO2 NPs suspensions at 50mg/L, 100mg/L, and 200mg/L. Deionized water and CA at 100mg/L were used as controls. Results showed ζ potential values of 21.6 mV and -56 mV for the pristine and CA coated CeO2 NPs, respectively. TEM images showed denser layers surrounding the CeO2 NPs at higher CA concentrations, as well as better distribution and smaller particle sizes. None of the treatments affected seed germination. However, at 200mg/L the CA coated NPs at 1:7 ratio produced significantly (p ≤ 0.05) more root biomass, increased water content and reduced by 94% the Ce uptake, compared to bare NPs. This suggests that CA coating decrease CeO2 NPs toxicity to plants.

  1. A reduced-order modeling approach to represent subgrid-scale hydrological dynamics for land-surface simulations: application in a polygonal tundra landscape

    Science.gov (United States)

    Pau, G. S. H.; Bisht, G.; Riley, W. J.

    2014-09-01

    Existing land surface models (LSMs) describe physical and biological processes that occur over a wide range of spatial and temporal scales. For example, biogeochemical and hydrological processes responsible for carbon (CO2, CH4) exchanges with the atmosphere range from the molecular scale (pore-scale O2 consumption) to tens of kilometers (vegetation distribution, river networks). Additionally, many processes within LSMs are nonlinearly coupled (e.g., methane production and soil moisture dynamics), and therefore simple linear upscaling techniques can result in large prediction error. In this paper we applied a reduced-order modeling (ROM) technique known as "proper orthogonal decomposition mapping method" that reconstructs temporally resolved fine-resolution solutions based on coarse-resolution solutions. We developed four different methods and applied them to four study sites in a polygonal tundra landscape near Barrow, Alaska. Coupled surface-subsurface isothermal simulations were performed for summer months (June-September) at fine (0.25 m) and coarse (8 m) horizontal resolutions. We used simulation results from three summer seasons (1998-2000) to build ROMs of the 4-D soil moisture field for the study sites individually (single-site) and aggregated (multi-site). The results indicate that the ROM produced a significant computational speedup (> 103) with very small relative approximation error (constructed at different scales together hierarchically, this method has the potential to efficiently increase the resolution of land models for coupled climate simulations to spatial scales consistent with mechanistic physical process representation.

  2. Non-inferiority of pulsed xenon UV light versus bleach for reducing environmental Clostridium difficile contamination on high-touch surfaces in Clostridium difficile infection isolation rooms.

    Science.gov (United States)

    Ghantoji, Shashank S; Stibich, Mark; Stachowiak, Julie; Cantu, Sherry; Adachi, Javier A; Raad, Issam I; Chemaly, Roy F

    2015-02-01

    The standard for Clostridium difficile surface decontamination is bleach solution at a concentration of 10 % of sodium hypochlorite. Pulsed xenon UV light (PX-UV) is a means of quickly producing germicidal UV that has been shown to be effective in reducing environmental contamination by C. difficile spores. The purpose of this study was to investigate whether PX-UV was equivalent to bleach for decontamination of surfaces in C. difficile infection isolation rooms. High-touch surfaces in rooms previously occupied by C. difficile infected patients were sampled after discharge but before and after cleaning using either bleach or non-bleach cleaning followed by 15 min of PX-UV treatment. A total of 298 samples were collected by using a moistened wipe specifically designed for the removal of spores. Prior to disinfection, the mean contamination level was 2.39 c.f.u. for bleach rooms and 22.97 for UV rooms. After disinfection, the mean level of contamination for bleach was 0.71 c.f.u. (P = 0.1380), and 1.19 c.f.u. (P = 0.0017) for PX-UV disinfected rooms. The difference in final contamination levels between the two cleaning protocols was not significantly different (P = 0.9838). PX-UV disinfection appears to be at least equivalent to bleach in the ability to decrease environmental contamination with C. difficile spores. Larger studies are needed to validate this conclusion. © 2015 The Authors.

  3. Effect of Hydrogen Peroxide in Combination with Minimal Thermal Treatment for Reducing Bacterial Populations on Cantaloupe Rind Surfaces and Transfer to Fresh-Cut Pieces.

    Science.gov (United States)

    Ukuku, Dike O; Mukhopadhyay, Sudarsan; Geveke, David; Olanya, Modesto; Niemira, Brendan

    2016-08-01

    Surface structure and biochemical characteristics of bacteria and produce play a major role in how and where bacteria attach, complicating decontamination treatments. Whole cantaloupe rind surfaces were inoculated with Salmonella, Escherichia coli O157:H7, and Listeria monocytogenes at 10(7) CFU/ml. Average population size of Salmonella, Escherichia coli O157:H7, and L. monocytogenes recovered after surface inoculation was 4.8 ± 0.12, 5.1 ± 0.14, and 3.6 ± 0.13 log CFU/cm(2), respectively. Inoculated melons were stored at 5 and 22°C for 7 days before washing treatment interventions. Intervention treatments used were (i) water (H2O) at 22°C, (ii) H2O at 80°C, (iii) 3% hydrogen peroxide (H2O2) at 22°C, and (iv) a combination of 3% H2O2 and H2O at 80°C for 300 s. The strength of pathogen attachment (SR value) at days 0, 3, and 7 of storage was determined, and then the efficacy of the intervention treatments to detach, kill, and reduce transfer of bacteria to fresh-cut pieces during fresh-cut preparation was investigated. Populations of E. coli O157:H7 attached to the rind surface at significantly higher levels (P < 0.05) than Salmonella and L. monocytogenes, but Salmonella exhibited the strongest attachment (SR value) at all days tested. Washing with 3% H2O2 alone led to significant reduction (P < 0.05) of bacteria and caused some changes in bacterial cell morphology. A combination treatment with H2O and 3% H2O2 at 8°C led to an average 4-log reduction of bacterial pathogens, and no bacterial pathogens were detected in fresh-cut pieces prepared from this combination treatment, including enriched fresh-cut samples. The results of this study indicate that the microbial safety of fresh-cut pieces from treated cantaloupes was improved at day 6 of storage at 5°C and day 3 of storage at 10°C.

  4. Fabrication of friction-reducing texture surface by selective laser melting of ink-printed (SLM-IP) copper (Cu) nanoparticles(NPs)

    Science.gov (United States)

    Wang, Xinjian; Liu, Junyan; Wang, Yang; Fu, Yanan

    2017-02-01

    This paper reports a process of selective laser melting of ink-printed (SLM-IP) copper (Cu) nanoparticles(NPs) for the fabrication of full dense Cu friction-reducing texture on the metallic surface in ambient condition. This technique synthesizes pure Cu by chemical reduction route using an organic solvent during laser melting in the atmosphere environment, and provides a flexible additive manufacture approach to form complex friction-reduction texture on the metallic surface. Microtextures of ring and disc arrays have been fabricated on the stainless steel surface by SLM-IP Cu NPs. The friction coefficient has been measured under the lubricating condition of the oil. Disc texture surface (DTS) has a relatively low friction coefficient compared with ring texture surface (RTS), Cu film surface (Cu-FS) and the untreated substrate. The study suggests a further research on SLM-IP approach for complex microstructure or texture manufacturing, possibly realizing its advantage of flexibility.

  5. Significant improvement of near-UV electroluminescence from ZnO quantum dot LEDs via coupling with carbon nanodot surface plasmons.

    Science.gov (United States)

    Zhang, Cen; Zhu, Feifei; Xu, Haiyang; Liu, Weizhen; Yang, Liu; Wang, Zhongqiang; Ma, Jiangang; Kang, Zhenhui; Liu, Yichun

    2017-10-05

    Short-wavelength LEDs, a hot research topic in modern optoelectronics, have attracted tremendous attention in recent years because of their great application potential in both civil and military domains. Compared to conventional metallic surface-plasmons (SPs), carbon nanodot (CD) SPs with less optical loss and low cost, broader SP resonant frequency and good biocompatibility are expected to provide more prominent luminescence enhancement for light emitters. Herein, SP-enhanced near-UV emission quantum dot LEDs (Q-LED) were fabricated via introducing CDs into p-GaN/Al2O3/ZnO Q-LEDs by optimizing the molar ratio of ZnO quantum dots to CDs and a significant enhancement (∼20-fold) of the near-UV electroluminescence (EL) intensity from the ZnO-based Q-LEDs was achieved. Time-resolved spectroscopy studies reveal that the observed luminescence enhancement arises due to the resonant coupling between ZnO excitons and CD SPs. The current study not only demonstrates a feasible way to acquire near-UV emission from all-inorganic Q-LEDs, but also provides an effective strategy to enhance the EL intensity of these QD light emitters, which can further be extended to other types of light-emitting devices to improve EL efficiency.

  6. Measures to reduce glyphosate runoff from hard surfaces, 2: effect of time interval between application and first precipitation event

    NARCIS (Netherlands)

    Luijendijk, C.D.; Beltman, W.H.J.; Smidt, R.A.; Pas, van der L.J.T.; Kempenaar, C.

    2005-01-01

    In this research the effect of moisture conditions of hard surfaces on emission of herbicides from hard surfaces was quantified. In addition the dissipation of glyphosate applied on brick-pavement is determined in time. The outdoor experiment was carried out on 3 and 17 June 2003. In previous

  7. Measures to reduce glyphosate runoff from hard surfaces, 2: effect of time interval between application and first precipitation event

    NARCIS (Netherlands)

    Luijendijk, C.D.; Beltman, W.H.J.; Smidt, R.A.; Pas, van der L.J.T.; Kempenaar, C.

    2005-01-01

    In this research the effect of moisture conditions of hard surfaces on emission of herbicides from hard surfaces was quantified. In addition the dissipation of glyphosate applied on brick-pavement is determined in time. The outdoor experiment was carried out on 3 and 17 June 2003. In previous resear

  8. Eddy Covariance Tilt Corrections over a Coastal Mountain Area in South-east China: Significance for Near-Surface Turbulence Characteristics

    Institute of Scientific and Technical Information of China (English)

    LIU Li; WANG Tijian; SUN Zhenhai; WANG Qingeng; ZHUANG Bingliang; HAN Yong; LI Shu

    2012-01-01

    Turbulence characteristics of an atmospheric surface layer over a coastal mountain area were investigated under different coordinate frames.Performances of three methods of coordinate rotation:double rotation (DR),triple rotation (TR),and classic planar-fit rotation (PF) were examined in terms of correction of eddy covariance flux. Using the commonly used DR and TR methods,unreasonable rotation angles are encountered at low wind speeds and cause significant run-to-run errors of some turbulence characteristics.The PF method rotates the coordinate system to an ensemble-averaged plane,and shows large tilt error due to an inaccurate fit plane over variable terrain slopes.In this paper,we propose another coordinate rotation scheme.The observational data were separated into two groups according to wind direction.The PF method was adapted to find an ensemble-averaged streamline plane for each group of hourly runs with wind speed exceeding 1.0 m s-1. Then,the coordinate systems were rotated to their respective bestfit planes for all available hourly observations. We call this the PF10 inethod. The implications of tilt corrections for the turbulence characteristics are discussed with a focus on integral turbulence characteristics,the spectra of wind-velocity components,and sensible heat and momentum fluxes under various atmospheric stabilities. Our results show that the adapted application of PF provides greatly improved estimates of integral turbulence characteristics in complex terrain and maintains data quality.The comparisons of the sensible heat fluxes for four coordinate rotation methods to fluxes before correction indicate that the PF10 scheme is the best to preserve consistency between fluxes.

  9. Polymer-Based Surfaces Designed to Reduce Biofilm Formation: From Antimicrobial Polymers to Strategies for Long-Term Applications.

    Science.gov (United States)

    Riga, Esther K; Vöhringer, Maria; Widyaya, Vania Tanda; Lienkamp, Karen

    2017-08-28

    Contact-active antimicrobial polymer surfaces bear cationic charges and kill or deactivate bacteria by interaction with the negatively charged parts of their cell envelope (lipopolysaccharides, peptidoglycan, and membrane lipids). The exact mechanism of this interaction is still under debate. While cationic antimicrobial polymer surfaces can be very useful for short-term applications, they lose their activity once they are contaminated by a sufficiently thick layer of adhering biomolecules or bacterial cell debris. This layer shields incoming bacteria from the antimicrobially active cationic surface moieties. Besides discussing antimicrobial surfaces, this feature article focuses on recent strategies that were developed to overcome the contamination problem. This includes bifunctional materials with simultaneously presented antimicrobial and protein-repellent moieties; polymer surfaces that can be switched from an antimicrobial, cell-attractive to a cell-repellent state; polymer surfaces that can be regenerated by enzyme action; degradable antimicrobial polymers; and antimicrobial polymer surfaces with removable top layers. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Fact Sheet: Final Rule to Reduce Toxic Air Pollutants from Surface Coating of Miscellaneous Metal Parts and Products

    Science.gov (United States)

    This page contains an August 2003 fact sheet with information regarding the National Emission Standards for Miscellaneous Metal Parts and Products Surface Coating Operations. This document provides a summary of the information for this regulation.

  11. SURFACE FINISHES ON STAINLESS STEEL REDUCE BACTERIAL ATTACHMENT AND EARLY BIOFILM FORMATION: SCANNING ELECTRON AND ATOMIC FORCE MICROSCOPY STUDY

    Science.gov (United States)

    Three common finishing treatments of stainless steel that are used for equipment during poultry processing were tested for resistance to bacterial contamination. Methods were developed to measure attached bacteria and to identify factors that make surface finishes susceptible or ...

  12. Mining soil phosphorus by zero P-application: an effective method to reduce the risk of P loading to surface water

    NARCIS (Netherlands)

    Salm, van der C.; Chardon, W.J.; Koopmans, G.F.

    2007-01-01

    This study aims to find field evidence for the effectiveness of P-mining to reduce the risk of P leaching to surface water. In 2002, a P-mining was conducted on four grassland sites in the Netherlands on sand (two sites), peat and clay soils. The mining plots received no P and an annual N surplus of

  13. Elaboration of highly hydrophobic polymeric surface — a potential strategy to reduce the adhesion of pathogenic bacteria?

    Energy Technology Data Exchange (ETDEWEB)

    Poncin-Epaillard, F., E-mail: fabienne.poncin-epaillard@univ-lemans.fr [Institut des Molécules et Matériaux du Mans (IMMM), département Polymères, Colloïdes et Interfaces, UMR CNRS 6283 Université LUNAM, av. O. Messiaen, 72085 Le Mans (France); Herry, J.M. [INRA-AgroParisTech, UMR 1319 MICALIS, équipe B2HM, 25 avenue de la République, 91300 Massy (France); Marmey, P.; Legeay, G. [CTTM, 20 rue Thalès de Milet 72000 Le Mans (France); Debarnot, D. [Institut des Molécules et Matériaux du Mans (IMMM), département Polymères, Colloïdes et Interfaces, UMR CNRS 6283 Université LUNAM, av. O. Messiaen, 72085 Le Mans (France); Bellon-Fontaine, M.N. [INRA-AgroParisTech, UMR 1319 MICALIS, équipe B2HM, 25 avenue de la République, 91300 Massy (France)

    2013-04-01

    Different polymeric surfaces have been modified in order to reach a high hydrophobic character, indeed the superhydrophobicity property. For this purpose, polypropylene and polystyrene have been treated by RF or μwaves CF{sub 4} plasma with different volumes, the results were compared according to the density of injected power. The effect of pretreatment such as mechanical abrasion or plasma activation was also studied. The modified surfaces were shown as hydrophobic, or even superhydrophobic depending of defects density. They were characterized by measurement of wettability and roughness at different scales, i.e. macroscopic, mesoscopic and atomic. It has been shown that a homogeneous surface at the macroscopic scale could be heterogeneous at lower mesoscopic scale. This was associated with the crystallinity of the material. The bioadhesion tests were performed with Gram positive and negative pathogenic strains: Listeria monocytogenes, Pseudomonas aeruginosa and Hafnia alvei. They have demonstrated an antibacterial efficiency of very hydrophobic and amorphous PS treated for all strains tested and a strain-dependent efficiency with modified PP surface being very heterogeneous at the mesoscopic scale. Thus, these biological results pointed out not only the respective role of the surface chemistry and topography in bacterial adhesion, but also the dependence on the peaks and valley distribution at bacteria dimension scale. Highlights: ► Simple, eco-friendly modification of polymers leading to highly hydrophobic property ► Plasma treatment inducing surface fluorination and roughness ► Study of non-adhesion of different types of bacteria onto such polymeric surfaces ► Dependence of their non-adhesion on surface topography whatever their characteristics.

  14. H2S adsorption and decomposition on the gradually reduced α-Fe2O3(001) surface: A DFT study

    Science.gov (United States)

    Lin, Changfeng; Qin, Wu; Dong, Changqing

    2016-11-01

    Reduction of iron based desulfurizer occurs during hot gas desulfurization process, which will affect the interaction between H2S and the desulfurizer surface. In this work, a detailed adsorption behavior and dissociation mechanism of H2S on the perfect and reduced α-Fe2O3(001) surfaces, as well as the correlation between the interaction characteristic and reduction degree of iron oxide, have been studied by using periodic density functional theory (DFT) calculations. Results demonstrate that H2S firstly chemisorbs on surface at relatively higher oxidation state (reduction degree χ 33%. Reduction of iron oxide benefits the H2S adsorption. Further, dissociation processes of H2S via molecular and dissociative adsorption were investigated. Results show that after reduction of Fe2O3 into the oxidation state around FeO and Fe, the reduced surface exhibits very strong catalytic capacity for H2S decomposition into S species. Meanwhile, the overall dissociation process on all surfaces is exothermic. These results provide a fundamental understanding of reduction effect of iron oxide on the interaction mechanism between H2S and desulfurizer surface, and indicate that rational control of reduction degree of desulfurizer is essential for optimizing the hot gas desulfurization process.

  15. A facile and green method for synthesis of reduced graphene oxide/Ag hybrids as efficient surface enhanced Raman scattering platforms.

    Science.gov (United States)

    Huang, Qingli; Wang, Jiaming; Wei, Wenxian; Yan, Qiuxiang; Wu, Changle; Zhu, Xiashi

    2015-01-01

    Reduced graphene oxide/Ag nanoparticles hybrids (rGO/AgNPs) were fabricated via a green and facile hydrothermal method. The as-synthesized materials were characterized in detail using various spectroscopic and microscopic techniques. Under a suitable dosage of silver ions, well-dispersed AgNPs on the reduced graphene oxide sheets were obtained. The surface plasmon resonance properties of AgNPs on graphene show that there is an interaction between AgNPs and graphene. Trace detection of organic dyes is studied based on rGO/AgNPs hybrids as efficient surface enhanced Raman scattering platforms. It has been found that the suitable experiment parameter is crucial to trace detection of organic dyes molecules. This work is of importance in the practical application in device-design based on the SERS effect of noble metal/reduced oxide graphene (or oxide graphene) hybrids. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. High-risk human papillomavirus E7 expression reduces cell-surface MHC class I molecules and increases susceptibility to natural killer cells

    DEFF Research Database (Denmark)

    Bottley, G; Watherston, O G; Hiew, Y-L

    2007-01-01

    a role for E7 in tumour immune evasion. We show that knockdown of E7 expression in HPV16- and HPV18-transformed cervical carcinoma cells by RNA interference increased expression of major histocompatibility complex (MHC) class I at the cell surface and reduced susceptibility of these cells to natural...... killer (NK) cells. Tetracycline-regulated induction of HPV16 E7 resulted in reduced expression of cell surface MHC class I molecules and increased NK cell killing. Our results suggest that, for HPV-associated malignancies, reduced MHC class I expression is the result of an active immune evasion strategy......High-risk human papillomavirus (HPV) is a major causative agent of cervical cancer and the E6 and E7 genes encode the major HPV oncoproteins. The E7 protein from high-risk HPV types alters cell cycle progression and represses genes encoding components of the antigen-presentation pathway, suggesting...

  17. Anatomical significance of a posterior horn of medial meniscus: the relationship between its radial tear and cartilage degradation of joint surface

    Directory of Open Access Journals (Sweden)

    Kan Akinori

    2010-01-01

    Full Text Available Abstract Background Traumatic injury and surgical meniscectomy of a medial meniscus are known to cause subsequent knee osteoarthritis. However, the difference in the prevalence of osteoarthritis caused by the individual type of the medial meniscal tear has not been elucidated. The aim of this study was to investigate what type of tear is predominantly responsible for the degradation of articular cartilage in the medial compartment of knee joints. Methods Five hundred and forty eight cadaveric knees (290 male and 258 female were registered in this study. The average age of cadavers at death was 78.8 years old (range: 52-103 years. The knees were macroscopically examined and their medial menisci were classified into four groups according to types of tears: "no tear", "radial tear of posterior horn", "other types of tear" and "worn-out meniscus" groups. The severity of cartilage degradation in their medial compartment of knee joints was evaluated using the international cartilage repair society (ICRS grading system. We statistically compared the ICRS grades among the groups using Mann-Whitney U test. Results The knees were assigned into the four groups: 416 "no tear" knees, 51 "radial tear of posterior horn" knees, 71 "other types of tear" knees, and 10 "worn-out meniscus" knees. The knees with substantial meniscal tears showed the severer ICRS grades of cartilage degradation than those without meniscal tears. In addition, the ICRS grades were significantly severer in the "radial tear of posterior horn" group than in the "other types of tear" group, suggesting that the radial tear of posterior horn in the medial meniscus is one of the risk factors for cartilage degradation of joint surface. Conclusions We have clarified the relationship between the radial tear of posterior horn in the medial meniscus and the severer grade of cartilage degradation. This study indicates that the efforts should be made to restore the anatomical role of the posterior

  18. Does a micro-grooved trunnion stem surface finish improve fixation and reduce fretting wear at the taper junction of total hip replacements? A finite element evaluation.

    Science.gov (United States)

    Ashkanfar, Ariyan; Langton, David J; Joyce, Thomas J

    2017-08-10

    The generation of particulate debris at the taper junction of total hip replacements (THRs), can cause failure of the artificial hip. The taper surfaces of femoral heads and trunnions of femoral stems are generally machined to a certain roughness to enhance fixation. However, the effect of the surface roughness of these surfaces on the fixation, wear and consequently clinical outcomes of the design is largely unknown. In this study, we asked whether a micro-grooved trunnion surface finish (1) improves the fixation and (2) reduces the wear rate at the taper junction of THRs. We used 3D finite element (FE) models of THRs to, firstly, investigate the effect of initial fixation of a Cobalt-Chromium femoral head with a smooth taper surface mated with a Titanium (1) micro-grooved and (2) smooth, trunnion surface finishes. Secondly, we used a computational FE wear model to compare the wear evolution between the models, which was then validated against wear measurements of the taper surface of explanted femoral heads. The fixation at the taper junction was found to be better for the smooth couplings. Over a 7 million load cycle analysis in-silico, the linear wear depth and the total material loss was around 3.2 and 1.4 times higher for the femoral heads mated with micro-grooved trunnions. It was therefore concluded that smooth taper and trunnion surfaces will provide better fixation at the taper junction and reduce the volumetric wear rates. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. A novel facility for reduced-gravity testing: a set-up for studying low-velocity collisions into granular surfaces

    CERN Document Server

    Sunday, Cecily; Cherrier, Olivier; Serrano, Sara Morales; Nardi, Claudia Valeria; Janin, Tristan; Martinez, Iris Avila; Gourinat, Yves; Mimoun, David

    2016-01-01

    This work presents an experimental design for studying low-velocity collisions into granular surfaces in low-gravity. In the experiment apparatus, reduced-gravity is simulated by releasing a free-falling projectile into a surface container with a downward acceleration less than that of Earth's gravity. The acceleration of the surface is controlled through the use of an Atwood machine, or a system of pulleys and counterweights. The starting height of the surface container and the initial separation distance between the projectile and surface are variable and chosen to accommodate collision velocities up to 20 cm/s and effective accelerations of ~0.1 - 1.0 m/s^2. Accelerometers, placed on the surface container and inside the projectile, provide acceleration data, while high-speed cameras capture the collision and act as secondary data sources. The experiment is built into an existing 5.5 m drop-tower frame and requires the custom design of all components, including the projectile, surface sample container, rele...

  20. Reducing the V2O3(0001) surface through electron bombardment--a quantitative structure determination with I/V-LEED.

    Science.gov (United States)

    Feiten, Felix E; Kuhlenbeck, Helmut; Freund, Hans-Joachim

    2016-01-28

    The (0001) surface of vanadium sesquioxide, V2O3, is terminated by vanadyl groups under standard ultra high vacuum preparation conditions. Reduction with electrons results in a chemically highly active surface with a well-defined LEED pattern indicating a high degree of order. In this work we report the first quantitative structure determination of a reduced V2O3(0001) surface. We identify two distinct surface phases by STM, one well ordered and one less well ordered. I/V-LEED shows the ordered phase to be terminated by a single vanadium atom per surface unit cell on a quasi-hexagonal oxygen layer with three atoms per two-dimensional unit cell. Furthermore we compare the method of surface reduction via electron bombardment with the deposition of V onto a vanadyl terminated film. The latter procedure was previously proposed to result in a structure with three surface vanadium atoms in the 2D unit cell and we confirm this with simulated STM images.

  1. A bioactive elastin-like recombinamer reduces unspecific protein adsorption and enhances cell response on titanium surfaces.

    Science.gov (United States)

    Salvagni, Emiliano; Berguig, Geoffrey; Engel, Elisabeth; Rodriguez-Cabello, J Carlos; Coullerez, Geraldine; Textor, Marcus; Planell, Josep A; Gil, F Javier; Aparicio, Conrado

    2014-02-01

    We present the immobilization on synthetic substrates of elastin-like recombinamers (ELR) that combine a bioactive motif for cell adhesion with protein antifouling properties. Physical adsorption of the recombinamers and covalent-grafting through organosilane chemistry were investigated. The biochemically-modified surfaces were thoroughly characterized and tested for protein absorption in serum by fluorescence-labelling, XPS, Ellipsometry, and OWLS. The ELR were successfully grafted and stable, even upon mechanical stresses; being the covalent bonding favourable over physical adsorption. The coated metal surfaces exhibited excellent reduction of serum protein adsorption (9 ng/cm(2)) compared to the bare metal surface (310 ng/cm(2)). Non-specific protein adsorption may mask the introduced bioactive motifs; therefore, the bioactivated surfaces should display serum-protein antifouling properties. Finally, improved hMSCs response was assessed on the bioactivated substrates. In summary, the coatings simultaneously displayed anti-fouling and bioactive properties. These studies investigated key factors to enhance tissue material interactions fundamental for the design of bioactive devices and future biomedical applications.

  2. Significant role of adhesion properties of primary osteoblast-like cells in early adhesion events for chondroitin sulfate and dermatan sulfate surface molecules.

    Science.gov (United States)

    Stanford, C M; Solursh, M; Keller, J C

    1999-12-05

    The purpose of this study was to characterize the role of cell surface adhesive macromolecules through enzyme modulation and metabolic recovery prior to and during a kinetic cell adhesion assay. Primary rat calvarial osteoblast-like cells were derived from Sprague-Dawley calvarial plates. Cell adhesion kinetics was evaluated with the definition of first-order adhesion kinetics. Osteoblasts were incubated in an adhesion buffer for 1 h prior to a cell attachment assay using various enzymes to remove cell surface glycosaminoglycans (GAGs). A subtractive adhesion analysis was performed by plating cells at 5 x 10(4)/well for variable periods through 2 h. The medium was collected, the well surface washed and pooled, and the number of cells enumerated with a Coulter Counter. Cell adhesion demonstrated first-order logarithmic adhesion kinetics in the first 60 min. Scatchard analysis demonstrated a linear relationship. Preexposure of cells to various enzyme combinations demonstrated that 50% of the equilibrium adhesion was dependent on chondroitin sulfate or dermatan sulfate surface macromolecules. These results were confirmed with pretreatment with a metabolic inhibitor of GAG synthesis (beta-D-xyloside). These results suggest an important role for cell associated chondroitin sulfate and dermatan sulfate in cell adhesion in addition to Arg-Gly-Asp or integrin mediated adhesion events.

  3. Optimization of fat-reduced ice cream formulation employing inulin as fat replacer via response surface methodology.

    Science.gov (United States)

    Pintor, Aurora; Severiano-Pérez, Patricia; Totosaus, Alfonso

    2014-10-01

    The use of new ingredients like inulin for fat replacement is of wide application in the food industry. The aim of the present work was to reduce the fat content on ice cream formulations. It was possible to reduce up to 25% of butyric and vegetable fats with 3% of inulin, with good textural and sensory characteristics of the final product. The substitution of fat with inulin increased the ice cream mix viscosity, improved air incorporation, and produced ice cream with soft and homogeneous textures. Color characteristics were not affected by the replacement. Hedonic sensory analysis showed that optimized fat-reduced inulin ice cream was not perceived different to commercial vanilla ice cream.

  4. Prediction and rational correlation of thermophoretically reduced particle mass transfer to hot surfaces across laminar or turbulent forced-convection gas boundary layers

    Science.gov (United States)

    Gokoglu, Suleyman A.; Rosner, Daniel E.

    1986-01-01

    A formulation previously developed to predict and correlate the thermophoretically-augmented submicron particle mass transfer rate to cold surfaces is found to account for the thermophoretically reduced particle mass transfer rate to overheated surfaces such that thermophoresis brings about a 10-decade reduction below the convective mass transfer rate expected by pure Brownian diffusion and convection alone. Thermophoretic blowing is shown to produce effects on particle concentration boundary-layer (BL) structure and wall mass transfer rates similar to those produced by real blowing through a porous wall. The applicability of the correlations to developing BL-situations is demonstrated by a numerical example relevant to wet-steam technology.

  5. Surface application of soybean peroxidase and calcium peroxide for reducing odorous VOC emissions from swine manure slurry

    Science.gov (United States)

    A laboratory experiment was conducted to evaluate and compare topical and fully mixed treatments of soybean peroxidase and calcium peroxide (SBP/CaO2) for reducing odorous volatile organic compound (VOC) emissions from swine manure slurry. The five treatments consisted of a control, the fully mixed ...

  6. Newly developed surface modification punches treated with alloying techniques reduce sticking during the manufacture of ibuprofen tablets.

    Science.gov (United States)

    Uchimoto, Takeaki; Iwao, Yasunori; Yamamoto, Tatsuya; Sawaguchi, Kazuo; Moriuchi, Toshiaki; Noguchi, Shuji; Itai, Shigeru

    2013-01-30

    Sticking is a serious problem during the manufacturing process of tablets. In order to prevent this, we used alloying techniques to prepare metal hardening (MH) and electron beam processing infinite product (EIP) punches with rougher asperity of surfaces than a hard chrome plated (HCr) punch. This study evaluated the anti-sticking properties of the MH and EIP punches compared to the HCr punch, using quantitative scraper force measurements and visual observation, for the manufacture of ibuprofen (Ibu) tablets. The anti-sticking property mechanism of the MH and EIP punches was also confirmed. The amount of Ibu adhering to the punch surface was 66% lower for the MH and EIP punches than for the HCr punch, suggesting a superior anti-sticking property of the MH and EIP punches. The scraper force of the HCr punch was 2.60-4.28 N, while that for the MH and EIP punches was 0.54-1.64 N and 0.42-1.33 N, respectively. The result of X-ray photoelectron spectroscopy suggested that the anti-sticking property of the EIP punch was attributed by the rough asperity as well as existence of low friction substance carbon fluoride on the punch surface. In conclusion, this study provides new evidence for the mechanisms behind the superior anti-sticking property of the MH and EIP punches. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Adsorption of a PEO-PPO-PEO triblock copolymer on metal oxide surfaces with a view to reducing protein adsorption and further biofouling.

    Science.gov (United States)

    Yang, Y; Poleunis, C; Románszki, L; Telegdi, J; Dupont-Gillain, C C

    2013-01-01

    Abstract Biomolecule adsorption is the first stage of biofouling. The aim of this work was to reduce the adsorption of proteins on stainless steel (SS) and titanium surfaces by modifying them with a poly(ethylene oxide) (PEO)-poly(propylene oxide) (PPO)-PEO triblock copolymer. Anchoring of the central PPO block of the copolymer is known to be favoured by hydrophobic interaction with the substratum. Therefore, the surfaces of metal oxides were first modified by self-assembly of octadecylphosphonic acid. PEO-PPO-PEO preadsorbed on the hydrophobized surfaces of titanium or SS was shown to prevent the adsorption of bovine serum albumin (BSA), fibrinogen and cytochrome C, as monitored by quartz crystal microbalance (QCM). Moreover, X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry were used to characterize the surfaces of the SS and titanium after competitive adsorption of PEO-PPO-PEO and BSA. The results show that the adsorption of BSA is well prevented on hydrophobized surfaces, in contrast to the surfaces of native metal oxides.

  8. Enhanced performance of dye-sensitized solar cells with dual-function coadsorbent: reducing the surface concentration of dye-iodine complexes concomitant with attenuated charge recombination.

    Science.gov (United States)

    Mazloum-Ardakani, Mohammad; Khoshroo, Alireza

    2015-09-21

    In this paper, we have investigated the effects of oleic acid as a dual-function coadsorbent on recombination and iodine binding in dye-sensitized solar cells. Oleic acid as a dual-function coadsorbent effectively shields the back electron transfer from TiO2 to I3(-) ions and also reduces the surface concentration of dye-I2 complexes via iodine binding to the unsaturated double bond on oleic acid. It was found that interaction between iodine and the double bond of oleic acid keeps the iodine molecules away from the surface and reduces the recombination rate between injected electrons in a semiconductor and iodine molecules and also increases open-circuit voltage. Furthermore, the interaction between iodine molecules and unexcited dyes affects the UV-Vis spectrum of them and prevents an unfavorable blue shift. Overall, the results point to an improved performance for DSC operation and development.

  9. SOD1 Mutations Targeting Surface Hydrogen Bonds Promote Amyotrophic Lateral Sclerosis without Reducing Apo-state Stability*

    OpenAIRE

    Byström, Roberth; Andersen, Peter M.; Gröbner, Gerhard; Oliveberg, Mikael

    2010-01-01

    In good accord with the protein aggregation hypothesis for neurodegenerative diseases, ALS-associated SOD1 mutations are found to reduce structural stability or net repulsive charge. Moreover there are weak indications that the ALS disease progression rate is correlated with the degree of mutational impact on the apoSOD1 structure. A bottleneck for obtaining more conclusive information about these structure-disease relationships, however, is the large intrinsic variability in patient survival...

  10. Emissions of reduced sulphur compounds from the surface of primary and secondary wastewater clarifiers at a Kraft Mill.

    Science.gov (United States)

    Catalan, Lionel; Liang, Victor; Johnson, Andrea; Jia, Charles; O'Connor, Brian; Walton, Chris

    2009-09-01

    Emissions of reduced sulphur compounds (RSCs) from the primary and secondary clarifiers at a Kraft mill were measured for respectively 8 and 22 days using a floating flux chamber. In the primary clarifier, dimethyl disulphide (DMDS) had the highest mean flux (0.83 microg s(-1) m(-2)) among all RSCs, and the mean flux of total reduced sulphur (TRS) was 1.53 microg s(-1) m(-2). At the secondary clarifier, dimethyl sulphide (DMS) had the highest mean flux (0.024 microg s(-1) m(-2)), and the mean flux of total reduced sulphur (TRS) was 0.025 microg s(-1) m(-2). Large variations in fluxes as a function of sampling date were observed in both clarifiers. Emission fluxes of DMS from the secondary clarifier were correlated with temperature in the flux chamber and with the biological and chemical oxygen demands (BOD and COD) of the wastewater. Emission rates of RSCs from the clarifiers were found to be insignificant by comparison with other mill sources.

  11. Combination treatment of human umbilical cord matrix stem cell-based interferon-beta gene therapy and 5-fluorouracil significantly reduces growth of metastatic human breast cancer in SCID mouse lungs.

    Science.gov (United States)

    Rachakatla, Raja Shekar; Pyle, Marla M; Ayuzawa, Rie; Edwards, Sarah M; Marini, Frank C; Weiss, Mark L; Tamura, Masaaki; Troyer, Deryl

    2008-08-01

    Umbilical cord matrix stem (UCMS) cells that were engineered to express interferon-beta (IFN-beta) were transplanted weekly for three weeks into MDA 231 breast cancer xenografts bearing SCID mice in combination with 5-fluorouracil (5-FU). The UCMS cells were found within lung tumors but not in other tissues. Although both treatments significantly reduced MDA 231 tumor area in the SCID mouse lungs, the combined treatment resulted in a greater reduction in tumor area than by either treatment used alone. These results indicate that a combination treatment of UCMS-IFN-beta cells and 5-FU is a potentially effective therapeutic procedure for breast cancer.

  12. Testing road surface treatments to reduce erosion in forest roads in Honduras [Tratamientos de la superficie de rodadura para reducir la erosion en caminos forestales en Honduras

    Science.gov (United States)

    Rivera, Samuel; Kershner, Jeffrey L.; Keller, Gordon R.

    2009-01-01

    Testing road surface treatments to reduce erosion in forest roads in Honduras. Cien. Inv. Agr. 36(3):425-432. Using forest roads produces more erosion and sedimentation than any other forest or agricultural activity. This study evaluated soil losses from a forest road in central Honduras over two consecutive years. We divided a 400-m segment of road into 8 experimental units, each 50 m in length. Four units were treated with Best Management Practices (BMPs) and four were left untreated. The BMP treatments included reshaping the road prism, installing culverts and reshaping of road ditches, compacting 20-cm layers of the road tread, crowning the road surface (3% slope, double drainage), longitudinal sloping (less than 12%), and adding a 10-cm layer of gravel (crush size = 0.63 cm). Soil movement was measured daily during the rainy seasons. The highest soil loss occurred in the control road, around 500 m3 km-1 per year, while the road treated with BMP lost approximately 225 m3km-1 per year. These results show that road surface erosion can be reduced up to 50% with the implementation of surface treatments.

  13. CO2 dissociation activated through electron attachment on reduced rutile TiO2(110)-1x1 surface

    CERN Document Server

    Tan, Shijing; Zhao, Jin; Wang, Zhuo; Ma, Chuanxu; Zhao, Aidi; Wang, Bing; Luo, Yi; Yang, Jinlong; Hou, Jianguo

    2011-01-01

    Converting CO$_2$ to useful compounds through the solar photocatalytic reduction has been one of the most promising strategies for artificial carbon recycling. The highly relevant photocatalytic substrate for CO$_2$ conversion has been the popular TiO$_2$ surfaces. However, the lack of accurate fundamental parameters that determine the CO$_2$ reduction on TiO$_2$ has limited our ability to control these complicated photocatalysis processes. We have systematically studied the reduction of CO2 at specific sites of the rutile TiO$_2$(110)-1x1 surface using scanning tunneling microscopy at 80 K. The dissociation of CO2 molecules is found to be activated by one electron attachment process and its energy threshold, corresponding to the CO$_2^{\\dot-}$/CO$_2$ redox potential, is unambiguously determined to be 2.3 eV higher than the onset of the TiO$_2$ conduction band. The dissociation rate as a function of electron injection energy is also provided. Such information can be used as practical guidelines for the design...

  14. Localized CO2 laser treatment and post-heating process to reduce the growth coefficient of fused silica surface damage

    Institute of Scientific and Technical Information of China (English)

    Shizhen Xu; Xiaotao Zu; Xiaodong Yuan

    2011-01-01

    The lifetime of optical components in high-fluence ultraviolet (UV) laser applications is typically limited by laser-initiated damage and its subsequent growth. Using 10.6-μm CO2 laser pulses, we successfully mitigate 355-nm laser induced damage sites on fused silica surface with dimensions less than 200 μm.The damage threshold increases and the damage growth mitigates. However, the growth coefficients of new damage on the CO2 laser processed area are higher than those of the original sample. The damage grows with crack propagation for residual stress after CO2 laser irradiation. Furthermore, post-heating is beneficial to the release of residual stress and slows down the damage growth.%@@ The lifetime of optical components in high-fluence ultraviolet (UV) laser applications is typically limited by laser-initiated damage and its subsequent growth.Using 10.6-μm CO2 laser pulses, we successfully mitigate 355-nm laser induced damage sites on fused silica surface with dimensions less than 200 μm.The damage threshold increases and the damage growth mitigates.However, the growth coefficients of new damage on the CO2 laser processed area are higher than those of the original sample.The damage grows with crack propagation for residual stress after CO2 laser irradiation.Furthermore, post-heating is beneficial to the release of residual stress and slows down the damage growth.

  15. Variation of Stable Isotopes in Surface Snow along a Traverse from Coast to Plateau’s interior in East Antarctica and Its Climatic Significance

    Institute of Scientific and Technical Information of China (English)

    Jean; Jouzel; Michel; Stievenard

    2009-01-01

    The variations of stable water isotopes of surface snow in east Antarctic Ice Sheet, are discussed by a total of 251 samples, which were taken along a 330 km traverse from Zhongshan Station to the outer edge of the Antarctic plateau and from four snow pits excavated along the route. Analyzing results of the samples showed the expected linear relationship between the parameters ?D and ?18O with slope S1 and intercept d1. When the data set was examined using a sliding window with a width of 5 samples, it was found that there were two areas with different ratios of S1 and d1. The boundary between these two areas occurred at an elevation of about 2,000 m, suggesting two different sources of water vapour. Nearly half (47%) of the fresh-snow samples had negative deuterium excess (d=?D? 8?18O) values, but few of the snow pit samples did, suggesting that variations of ? are quickly smoothed by isotopic diffusion in the near-surface firn. Analysis of the phase relationship between ?D and deuterium excess in the snow pit stratigraphies showed that they were mostly in phase from Jan. 1994 to Sept. 1995, but mostly out of phase from Sept. 1995 to Jan. 1997.

  16. The protease resistant surface (PRS) glycoconjugate from Trypanosoma congolense has an inositol-acylated glycosylphosphatidylinositol anchor, containing a significant proportion of myristate at the sn-2 position.

    Science.gov (United States)

    Greganova, Eva; Bütikofer, Peter; Acosta-Serrano, Alvaro

    2010-05-01

    In the tsetse fly, the surface of Trypanosoma congolense parasites is covered by a dense layer of glycosylphosphatidylinositol (GPI)-anchored molecules. These include EPGENGT procyclin and protease resistant surface molecule (PRS), as well as congolense epimastigote-specific protein, CESP, and glutamic acid- and alanine-rich protein (GARP). The GPI structures of EPGENGT and GARP have been partially elucidated, but very little is known about PRS. We now purified PRS and analyzed its GPI lipid structure and carbohydrate composition using mass spectrometry. We found that unlike EPGENGT and GARP, the GPI anchor of PRS is unusually composed of inositol-acylated diacyl-phosphatidylinositols, including species containing either myristic or oleic acid at the sn-2 position of the glycerol backbone. This is the first identification of a tri-acylated GPI anchor containing myristate in procyclic form trypanosomes. In addition, we found that PRS is highly rich in galactose and sialic acid residues, suggesting that it may represent a major acceptor of the parasite trans-sialidase.

  17. Surface Acoustic Wave Device with Reduced Insertion Loss by Electrospinning P(VDF-TrFE)/ZnO Nanocomposites

    Institute of Scientific and Technical Information of China (English)

    Robin Augustine; Frederic Sarry; Nandakumar Kalarikkal; Sabu Thomas; Laurent Badie; Didier Rouxel

    2016-01-01

    Surface acoustic wave (SAW) devices have been utilized for the sensing of chemical and biological phe-nomena in microscale for the past few decades. In this study, SAW device was fabricated by electrospinning poly(vinylidenefluoride-co-trifluoroethylene) (P(VDF-TrFE)) incorporated with zinc oxide (ZnO) nanoparticles over the delay line area of the SAW device. The morphology, composition, and crystallinity of P(VDF-TrFE)/ZnO nanocom-posites were investigated. After measurement of SAW frequency response, it was found that the insertion loss of the SAW devices incorporated with ZnO nanoparticles was much less than that of the neat polymer-deposited device. The fabricated device was expected to be used in acoustic biosensors to detect and quantify the cell proliferation in cell culture systems.

  18. Calcium insensitivity of FA-6, a cell line derived from a pancreatic cancer associated with humoral hypercalcemia, is mediated by the significantly reduced expression of the Calcium Sensitive Receptor transduction component p38 MAPK

    Directory of Open Access Journals (Sweden)

    Fairfax Benjamin

    2006-11-01

    Full Text Available Abstract The Calcium-Sensing Receptor is a key component of Calcium/Parathyroid hormone homeostatic system that helps maintain appropriate plasma Ca2+ concentrations. It also has a number of non-homeostatic functions, including cell cycle regulation through the p38 MAPK pathway, and recent studies have indicated that it is required for Ca2+ mediated growth arrest in pancreatic carcinoma cells. Some pancreatic cancers produce pathogenic amounts of parathyroid like hormones, however, which significantly increase Ca2+ plasma concentrations and might be expected to block further cell growth. In this study we have investigated the expression and function of the p38 MAPK signaling pathway in Ca2+ sensitive (T3M-4 and insensitive (FA6 pancreatic cancer cell lines. FA-6 cells, which are derived from a pancreatic adenocarcinoma that secretes a parathyroid hormone related peptide, exhibit only very low levels of p38 MAPK expression, relative to T3M-4 cells. Transfecting FA-6 cells with a p38 MAPK expression construct greatly increases their sensitivity to Ca2+. Furthermore, the reduction of p38 MAPK in T3M-4 cells significantly reduces the extent to which high levels of Ca2+ inhibit proliferation. These results suggest that the low levels of p38 MAPK expression in FA-6 cells may serve to reduce their sensitivity to high concentrations of external Ca2+ that would otherwise block proliferation.

  19. Linear and nonlinear properties of reduced two-layer models for non-hydrostatic free-surface flow

    Science.gov (United States)

    Bai, Yefei; Cheung, Kwok Fai

    2016-11-01

    A two-layer model with uniform non-hydrostatic pressure in the bottom produces favorable dispersion properties for coastal wave transformation at the computational requirements of a one-layer model. We derive the nonlinear governing equations and the corresponding dispersion relation, shoaling gradient, and super- and sub-harmonics to understand the theoretical performance of this reduced model. With the layer interface near the bottom, the dispersion relation shows an extended applicable range into deeper water at the expense of a slight overestimation of the celerity in intermediate water depth. The shoaling gradient rapidly converges to the exact solution in the shallow and intermediate depth range. These complementary characteristics allow identification of an optimal interface position for both linear wave properties. The resulting model exhibits good nonlinear performance in shallow and intermediate water depth and produces super- and sub-harmonics comparable to a two-layer model. Numerical tests involving standing waves show the reduced model has smaller discretization errors in the dispersion relation comparing to a one-layer model. Case studies of regular wave transformation over a submerged bar and a uniform slope provide comparison with laboratory data and demonstrate the linear and nonlinear properties derived from the governing equations. The good shoaling and nonlinear properties give rise to accurate waveforms in both cases, while dispersion errors from the governing equations and numerical schemes accumulate over time leading to phase shifts of the modeled waves.

  20. Effects of Gamma-Ray Irradiation on Dielectric Surface Breakdown of Polybutylene Naphthalate and Polybutylene Terephthalate Under Reduced Pressure

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    With the increasing application of electric and electronic devices in space and nuclear power stations, the polymeric insulation materials are inevitably exposed to various kinds of environments. Accordingly, it becomes necessary to investigate the effects of the radiation and air pressure on insulation materials. This paper describes the effects of gamma-ray irradiation and reduced pressure on dielectric breakdown of polybutylene naphthalate (PBN) and polybutylene terephthalate (PBT) by applying a DC pulse voltage. Both PBN and PBT were irradiated in air up to 100 kGy and then up to 1 000 kGy with a dose rate of 10 kGy/h by using a 60Co gamma-source. The effects of total dose and reduced pressure on the time to dielectric breakdown and discharge quantity were discussed. Obtained results show that, while increasing the total dose, the discharge quantity decreased with PBN, but increased with PBT. With decreasing the air pressure, the discharge quantity increased with PBN, but decreased with PBT. With increasing the total dose, the time to dielectric breakdown increased with PBN, but decreased with PBT. With decreasing the air pressure, the time to dielectric breakdown increased with both PBN and PBT. The experimental results suggest that the chemical structure of polybutylene polymers plays a main role in the result of radiation reaction,which is related to cross-linking and degradation reaction.

  1. No significant steady state surface creep along the North Anatolian Fault offshore Istanbul: Results of 6 months of seafloor acoustic ranging

    Science.gov (United States)

    Sakic, P.; Piété, H.; Ballu, V.; Royer, J.-Y.; Kopp, H.; Lange, D.; Petersen, F.; Özeren, M. S.; Ergintav, S.; Geli, L.; Henry, P.; Deschamps, A.

    2016-07-01

    The submarine Istanbul-Silivri fault segment, within 15 km of Istanbul, is the only portion of the North Anatolian Fault that has not ruptured in the last 250 years. We report first results of a seafloor acoustic ranging experiment to quantify current horizontal deformation along this segment and assess whether the segment is creeping aseismically or accumulating stress to be released in a future event. Ten transponders were installed to monitor length variations along 15 baselines. A joint least squares inversion for across-fault baseline changes, accounting for sound speed drift at each transponder, precludes fault displacement rates larger than a few millimeters per year during the 6 month observation period. Forward modeling shows that the data better fit a locked state or a very moderate surface creep—less than 6 mm/yr compared to a far-field slip rate of over 20 mm/yr—suggesting that the fault segment is currently accumulating stress.

  2. Roxarsone desorption from the surface of goethite by competitive anions, phosphate and hydroxide ions: Significance of the presence of metal ions.

    Science.gov (United States)

    Wang, Ling-Yuan; Wang, Shao-Wei; Chen, Wan-Ru

    2016-06-01

    Aromatic organoarsenical roxarsone (ROX) is a common additive for livestock feed. This arsenic containing pollutant could be discharged into the environment through agricultural application of animal manure, and pose potential threats to both humans and the wider environment. In this study, the influence of pH, competing anions and metal ions on the adsorption and desorption of ROX on goethite were investigated in order to understand their mobility in the environment. Both hydroxide ions and phosphate are common substances in the environment, and both are potential competing anions for ROX. Our results showed the addition of phosphate desorbed more ROX than the addition of hydroxide ions. As pH increased, the effect of phosphate did not show much difference to that of hydroxide ion. The results indicate that the presence of phosphate will greatly increase the mobility of ROX at low pH. Six common metal ions, including Zn(2+), Cu(2+), Fe(3+), Mn(2+), Mg(2+), and Ca(2+), were tested and all spiked metal ions enhanced the stability of ROX adsorption on the surface of goethite, and led to less desorption when phosphate was added. The results demonstrate that metal ions may form complex/surface precipitation with ROX to enhance its adsorption. The effect from Fe(3+), Zn(2+) and Cu(2+) was more pronounced than other metal ions, which might result from the fact that these three metal ions tend to associate with hydroxide ions and decrease the pH. The results of this research may shed light on the environmental fate and transportation of aromatic organoarsenicals in soil.

  3. Biofunctionalization of silicone rubber with microgroove-patterned surface and carbon-ion implantation to enhance biocompatibility and reduce capsule formation.

    Science.gov (United States)

    Lei, Ze-Yuan; Liu, Ting; Li, Wei-Juan; Shi, Xiao-Hua; Fan, Dong-Li

    Silicone rubber implants have been widely used to repair soft tissue defects and deformities. However, poor biocompatibility can elicit capsule formation, usually resulting in prosthesis contracture and displacement in long-term usage. To overcome this problem, this study investigated the properties of silicone rubber materials with or without a microgroove-patterned surface and with or without carbon (C)-ion implantation. Atomic force microscopy, X-ray photoelectron spectroscopy, and a water contact angle test were used to characterize surface morphology and physicochemical properties. Cytocompatibility was investigated by a cell adhesion experiment, immunofluorescence staining, a Cell Counting Kit-8 assay, and scanning electron microscopy in vitro. Histocompatibility was evaluated by studying the inflammatory response and fiber capsule formation that developed after subcutaneous implantation in rats for 7 days, 15 days, and 30 days in vivo. Parallel microgrooves were found on the surfaces of patterned silicone rubber (P-SR) and patterned C-ion-implanted silicone rubber (PC-SR). Irregular larger peaks and deeper valleys were present on the surface of silicone rubber implanted with C ions (C-SR). The silicone rubber surfaces with microgroove patterns had stable physical and chemical properties and exhibited moderate hydrophobicity. PC-SR exhibited moderately increased dermal fibroblast cell adhesion and growth, and its surface microstructure promoted orderly cell growth. Histocompatibility experiments on animals showed that both the anti-inflammatory and antifibrosis properties of PC-SR were slightly better than those of the other materials, and there was also a lower capsular contracture rate and less collagen deposition around implants made from PC-SR. Although the surface chemical properties, dermal fibroblast cell growth, and cell adhesion were not changed by microgroove pattern modification, a more orderly cell arrangement was obtained, leading to enhanced

  4. Surface modification and deuterium retention in reduced-activation steels under low-energy deuterium plasma exposure. Part I: undamaged steels

    Science.gov (United States)

    Ogorodnikova, O. V.; Zhou, Z.; Sugiyama, K.; Balden, M.; Gasparyan, Yu.; Efimov, V.

    2017-03-01

    In this paper, reduced-activation ferritic/martensitic (RAFM) steels including Eurofer (9Cr) and oxide dispersion strengthening (ODS) steels by the addition of Y2O3 particles with different amounts of Cr, namely, (9-16)Cr were exposed to low energy deuterium (D) plasma (~20-200 eV per D) up to a fluence of 2.9  ×  1025 D m-2 in the temperature range from 290 K to 700 K. The depth profile of D in steels was measured up to 8 µm depth by nuclear reaction analysis (NRA) and the total retained amount of D in those materials was determined by thermal desorption spectroscopy (TDS). It was found that the D retention in ODS steels is higher compared to Eurofer due to the much higher density of fine dispersoids and finer grain size. This work shows that in addition to the sintering temperature and time, the type, size and concentration of the doping particles have an enormous effect on the increase in the D retention. The D retention in undamaged ODS steels strongly depends on the Cr content: ODS with 12Cr has a minimum and the D retention in the case of ODS with (14-16)Cr is higher compared to (9-12)Cr. The replacing of Ti by Al in ODS-14Cr steels reduces the D retention. The formation of nano-structure surface roughness enriched in W or Ta due to combination of preferential sputtering of light elements and radiation-induced segregation was observed at incident D ion energy of 200 eV for both Eurofer and ODS steels. Both the surface roughness and the eroded layer enhance with increasing the temperature. The surface modifications result in a reduction of the D retention near the surface due to increasing the desorption flux and can reduce the overall D retention.

  5. Endomorphin 1[psi] and endomorphin 2[psi], endomorphins analogues containing a reduced (CH2NH) amide bond between Tyr1 and Pro2, display partial agonist potency but significant antinociception.

    Science.gov (United States)

    Zhao, Qian-Yu; Chen, Qiang; Yang, Ding-Jian; Feng, Yun; Long, Yuan; Wang, Peng; Wang, Rui

    2005-07-22

    Endomorphin 1 (EM1) and endomorphin 2 (EM2) are highly potent and selective mu-opioid receptor agonists and have significant antinociceptive action. In the mu-selective pocket of endomorphins (EMs), Pro2 residue is a spacer and directs the Tyr1 and Trp3/Phe3 side chains into the required orientation. The present work was designed to substitute the peptide bond between Tyr1 and Pro2 of EMs with a reduced (CH2NH) bond and study the agonist potency and antinociception of EM1[psi] (Tyr[psi(CH2NH)]Pro-Trp-Phe-NH2) and EM2[psi] (Tyr[psi(CH2NH)]Pro-Phe-Phe-NH2). Both EM1[psi] and EM2[psi] are partial mu opioid receptor agonists showing significant loss of agonist potency in GPI assay. However, EMs[psi] exhibited potent supraspinal antinociceptive action in vivo. In the mice tail-flick test, EMs[psi] (1, 5, 10 nmol/mouse, i.c.v.) produced potent and short-lasting antinociception in a dose-dependent and naloxone (1 mg/kg) reversed manner. At the highest dose of 10 nmol, the effect of EM2[psi] was prolonged and more significant than that of EM2. In the rat model of formalin injection induced inflammatory pain, EMs[psi] (0.1, 1, 10 nmol/rat, i.c.v.), like EMs, exerted transient but not dose-dependent antinociception. These results suggested that in the mu-selective pocket of EMs, the rigid conformation induced by the peptide bond between Tyr1 and Pro2 is essential to regulate their agonist properties at the mu opioid receptors. However, the increased conformational flexibility induced by the reduced (CH2NH) bond made less influence on their antinociception.

  6. Surface modification with poly(sulfobetaine methacrylate-co-acrylic acid) to reduce fibrinogen adsorption, platelet adhesion, and plasma coagulation.

    Science.gov (United States)

    Kuo, Wei-Hsuan; Wang, Meng-Jiy; Chien, Hsiu-Wen; Wei, Ta-Chin; Lee, Chiapyng; Tsai, Wei-Bor

    2011-12-12

    Zwitterionic sulfobetaine methacrylate (SBMA) polymers were known to possess excellent antifouling properties due to high hydration capacity and neutral charge surface. In this study, copolymers of SBMA and acrylic acid (AA) with a variety of compositions were synthesized and were immobilized onto polymeric substrates with layer-by-layer polyelectrolyte films via electrostatic interaction. The amounts of platelet adhesion and fibrinogen adsorption were determined to evaluate hemocompatibility of poly(SBMA-co-AA)-modified substrates. Among various deposition conditions by modulating SBMA ratio in the copolymers and pH of the deposition solution, poly(SBMA(56)-co-AA(44)) deposited at pH 3.0 possessed the best hemocompatibility. This work demonstrated that poly(SBMA-co-AA) copolymers adsorbed on polyelectrolyte-base films via electrostatic interaction improve hemocompatibility effectively and are applicable for various substrates including TCPS, PU, and PDMS. Furthermore, poly(SBMA-co-AA)-coated substrate possesses great durability under rigorous conditions. The preliminary hemocompatibility tests regarding platelet adhesion, fibrinogen adsorption, and plasma coagulation suggest the potential of this technique for the application to blood-contacting biomedical devices.

  7. Significance of frost action and surface soil characteristics to wind erosion at Rocky Flats, Colorado. Second progress report, October 1, 1975--May 30, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Caine, N.; Morin, P.

    1976-01-01

    This report summarizes information on soil frost effects collected on Rocky Flats during the 1975-1976 winter. On a broad scale, work on soil textures at and just below the ground surface corroborates the conclusion reached earlier that the general frost susceptibility of the Rocky Flats soils is quite well keyed to topography. This is incorporated into a mapping procedure for potential soil frost activity which is applied to the northwestern part of the Rocky Flats area. On a site scale, instrumental records of weather conditions and soil responses have been maintained from October, 1975, to May, 1976, at the Lindsay Ranch study site, northwest of the Rocky Flats Plant. During that period, 33 needle ice events have been observed and recorded and are described in this report. A preliminary examination of wind data for the same period suggests that the soil in areas of natural vegetation on the site are not exposed to wind action. If, however, they were exposed, winds capable of eroding them are common.

  8. Novel impedimetric immunosensor for the detection and quantitation of Adenovirus using reduced antibody fragments immobilized onto a conducting copolymer surface.

    Science.gov (United States)

    Caygill, Rebecca L; Hodges, Christopher S; Holmes, Joanne L; Higson, Séamus P J; Blair, G Eric; Millner, Paul A

    2012-02-15

    The number of Adenovirus (Ad) infections detected in immunocompromised people has increased due to the number of patients receiving transplants, as well as the HIV pandemic. Ads cause life-threatening diseases specific to the infected organs of immunocompromised hosts, with discontinuation of immunosuppressive agents necessary to prevent morbidity. The methodology in this paper has been employed to develop a novel impedimetric based assay platform to detect and quantify human Ads, which is comparable in performance to current methods, such as ELISA and PCR, but is also less expensive and faster. Novel immunosensors have been fabricated using polyclonal antibodies raised against a human Ad (Ad5) capsid protein, which were selectively cleaved into antibody fragments by 2-mercaptoethylamine. The fragments were immobilized onto a functionalized conducting copolymer matrix comprising polyaniline and 2-aminobenzylamine. Fully fabricated sensors were incubated with two immunologically distinct serotypes of Ad, Ad5 and Ad3, with between 10 and 10(12)virus particles/mL prior to sensor interrogation. Electrochemical impedance spectroscopy was used to measure the charge transfer resistance of the sensors over a range of frequencies from 25 kHz to 0.1 Hz. Our data demonstrate that the immunosensors specifically detect, and differentiate between, closely related human Ad serotypes with a limit of detection of 10(3)virus particles/mL. In addition, atomic force microscopy was applied to study the sensor surface nanostructure. Future work looks to test virus containing clinical samples but this could be a viable and valuable alternative for point-of-care virus detection and quantification.

  9. SOD1 mutations targeting surface hydrogen bonds promote amyotrophic lateral sclerosis without reducing apo-state stability.

    Science.gov (United States)

    Byström, Roberth; Andersen, Peter M; Gröbner, Gerhard; Oliveberg, Mikael

    2010-06-18

    In good accord with the protein aggregation hypothesis for neurodegenerative diseases, ALS-associated SOD1 mutations are found to reduce structural stability or net repulsive charge. Moreover there are weak indications that the ALS disease progression rate is correlated with the degree of mutational impact on the apoSOD1 structure. A bottleneck for obtaining more conclusive information about these structure-disease relationships, however, is the large intrinsic variability in patient survival times and insufficient disease statistics for the majority of ALS-provoking mutations. As an alternative test of the structure-disease relationship we focus here on the SOD1 mutations that appear to be outliers in the data set. The results identify several ALS-provoking mutations whose only effect on apoSOD1 is the elimination or introduction of a single charge, i.e. D76V/Y, D101N, and N139D/K. The thermodynamic stability and folding behavior of these mutants are indistinguishable from the wild-type control. Moreover, D101N is an outlier in the plot of stability loss versus patient survival time by having rapid disease progression. Common to the identified mutations is that they truncate conserved salt-links and/or H-bond networks in the functional loops IV or VII. The results show that the local impact of ALS-associated mutations on the SOD1 molecule can sometimes overrun their global effects on apo-state stability and net repulsive charge, and point at the analysis of property outliers as an efficient strategy for mapping out new ALS-provoking features.

  10. Variational reduced-density-matrix theory applied to the potential energy surfaces of carbon monoxide in the presence of electric fields.

    Science.gov (United States)

    Gidofalvi, Gergely; Mazziotti, David A

    2006-04-27

    The variational optimization of the energy with respect to the two-electron reduced-density matrix (2-RDM), constrained by N-representability conditions, can determine the shape of molecular potential energy surfaces with useful accuracy. In this paper, we apply the 2-RDM method with a first-order optimization algorithm [Mazziotti, D. A. Phys. Rev. Lett. 2004, 93, 213001] to investigating the potential energy surfaces of carbon monoxide in the presence and absence of an electric field. Two beneficial characteristics of the 2-RDM method for computing potential energy surfaces include the following: (i) its ability to capture multireference effects without specifying any reference wave function or density matrix and (ii) its guarantee of a global energy minimum in the variational optimization. The 2-RDM method produces electronic ground-state energies with similar accuracy at equilibrium and nonequilibrium geometries in both the presence and the absence of the electric field. Computed dipole moments are similar in accuracy to the values from the computationally expensive configuration interaction with single, double, triple, and quadruple excitations. These surfaces have important applications in quantum molecular control theory.

  11. Binary release of ascorbic acid and lecithin from core-shell nanofibers on blood-contacting surface for reducing long-term hemolysis of erythrocyte.

    Science.gov (United States)

    Shi, Qiang; Fan, Qunfu; Ye, Wei; Hou, Jianwen; Wong, Shing-Chung; Xu, Xiaodong; Yin, Jinghua

    2015-01-01

    There is an urgent need to develop blood-contacting biomaterials with long-term anti-hemolytic capability. To obtain such biomaterials, we coaxially electrospin [ascorbic acid (AA) and lecithin]/poly (ethylene oxide) (PEO) core-shell nanofibers onto the surface of styrene-b-(ethylene-co-butylene)-b-styrene elastomer (SEBS) that has been grafted with poly (ethylene glycol) (PEG) chains. Our strategy is based on that the grafted layers of PEG render the surface hydrophilic to reduce the mechanical injure to red blood cells (RBCs) while the AA and lecithin released from nanofibers on blood-contacting surface can actively interact with RBCs to decrease the oxidative damage to RBCs. We demonstrate that (AA and lecithin)/PEO core-shell structured nanofibers have been fabricated on the PEG grafted surface. The binary release of AA and lecithin in the distilled water is in a controlled manner and lasts for almost 5 days; during RBCs preservation, AA acts as an antioxidant and lecithin as a lipid supplier to the membrane of erythrocytes, resulting in low mechanical fragility and hemolysis of RBCs, as well as high deformability of stored RBCs. Our work thus makes a new approach to fabricate blood-contacting biomaterials with the capability of long-term anti-hemolysis. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Synthesis and voltammetry of [bmim]4[alpha-S2W18O62] and related compounds: rapid precipitation and dissolution of reduced surface films.

    Science.gov (United States)

    Mariotti, Andrew W A; Xie, Jingli; Abrahams, Brendan F; Bond, Alan M; Wedd, Anthony G

    2007-04-02

    1-n-Butyl-3-methylimidazolium (bmim) salts of [alpha-SiM12O40]4- and [alpha-S2M18O62]4- (M = Mo, W) were synthesized and characterized. In sharp contrast to the multiple one-electron diffusion-controlled reduction processes expected in solution at a glassy carbon electrode, reduction of these salts beyond the one-electron level in CH3CN (0.1 M [bmim][PF6]) led to rapid precipitation of arrays of microdroplets or microcrystals onto the surface. Upon oxidation these arrays dissolved on the electrochemical time scale, resulting in voltammograms displaying both diffusion-controlled and surface-confined behavior. These novel observations appear to be related to the ability of the [bmim]+ cations and polyoxometalate anions to form ion clusters in solution and to the lower solubilities of the reduced salts.

  13. Surface coating of siRNA-peptidomimetic nano-self-assemblies with anionic lipid bilayers: Enhanced gene silencing and reduced adversed effects in vitro

    DEFF Research Database (Denmark)

    Zeng, Xianghui; de Groot, A. M.; Sijts, Alice

    2015-01-01

    not display any noticeable cytotoxicity and immunogenicity in vitro. In contrast, the corresponding nanocomplexes mediated a reduced silencing effect with a more narrow safety window. The surface coating with anionic lipid bilayers led to partial decomplexation of the siRNA–peptidomimetic nanocomplex core...... of the liposomes, which facilitated siRNA release. Additionally, the optimal anionic liposomes showed efficient intracellular uptake and endosomal escape. Therefore, these findings suggest that a more efficacious and safe formulation can be achieved by surface coating of the siRNA–peptidomimetic nano...... a series of proteolytically stable palmitoylated α-peptide/β-peptoid peptidomimetics with a systematically varied number of repeating lysine and homoarginine residues was shown to self-assemble with small interfering RNA (siRNA). The resulting well-defined nanocomplexes were coated with anionic lipids...

  14. Significant cooling effect on the surface due to soot particles over Brahmaputra River Valley region, India: An impact on regional climate

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, S., E-mail: smbtiwari@tropmet.res.in [Indian Institute of Tropical Meteorology, New Delhi Branch, New Delhi 110060 (India); Department of Environmental Science and Analytical Chemistry, Stockholm University, Stockholm SE-10691 (Sweden); Kumar, R. [Research Application Laboratory, National Center for Atmospheric Research, Boulder, CO (United States); Tunved, P. [Department of Environmental Science and Analytical Chemistry, Stockholm University, Stockholm SE-10691 (Sweden); Singh, S. [CSIR, Central Institute of Mining & Fuel Research, Dhanbad, Jharkhand 826001 (India); Panicker, A.S. [Indian Institute of Tropical Meteorology, Pune 411008 (India)

    2016-08-15

    Black carbon (BC) is an important atmospheric aerosol constituent that affects the climate by absorbing (directly) the sunlight and modifying cloud characteristics (indirectly). Here, we present first time yearlong measurements of BC and carbon monoxide (CO) from an urban location of Guwahati located in the Brahmaputra River valley (BRV) in the northeast region of India from 1st July 2013 to 30th June 2014. Daily BC concentrations varied within the range of 2.86 to 11.56 μg m{sup −3} with an annual average of 7.17 ± 1.89 μg m{sup −3}{sub ,} while, CO varied from 0.19 to 1.20 ppm with a mean value of 0.51 ± 0.19 ppm during the study period. The concentrations of BC (8.37 μg m{sup −3}) and CO (0.67 ppm) were ~ 39% and ~ 55% higher during the dry months (October to March) than the wet months (April to September) suggesting that seasonal changes in meteorology and emission sources play an important role in controlling these species. The seasonal ΔBC/ΔCO ratios were highest (lowest) in the pre-monsoon (winter) 18.1 ± 1.4 μg m{sup −3} ppmv{sup −1} (12.6 ± 2.2 μg m{sup −3} ppmv{sup −1}) which indicate the combustion of biofuel/biomass as well as direct emissions from fossil fuel during the pre-monsoon season. The annual BC emission was estimated to be 2.72 Gg in and around Guwahati which is about 44% lower than the mega city ‘Delhi’ (4.86 Gg). During the study period, the annual mean radiative forcing (RF) at the top of the atmosphere (TOA) for clear skies of BC was + 9.5 Wm{sup −2}, however, the RF value at the surface (SFC) was − 21.1 Wm{sup −2} which indicates the net warming and cooling effects, respectively. The highest RF at SFC was in the month of April (− 30 Wm{sup −2}) which is coincident with the highest BC mass level. The BC atmospheric radiative forcing (ARF) was + 30.16 (annual mean) Wm{sup −2} varying from + 23.1 to + 43.8 Wm{sup −2}. The annual mean atmospheric heating rate (AHR) due to the BC aerosols was 0.86 K

  15. Occurrence of sulphate reducing bacteria (SRB associated with biocorrosion on metallic surfaces in a hydroelectric power station in Ibirama (SC - Brazil

    Directory of Open Access Journals (Sweden)

    Paulo Roberto Dantas Marangoni

    2013-10-01

    Full Text Available The aim of this study was evaluate, two methods for the detection and identification of sulphate reducing bacteria (SRB: ML medium and PCR with specific primers for SRB groups. SRB were detected through the selective medium only on carbon steel, which showed corrosion. Employing specific PCR primer, SBR were detected from all the metallic components assayed, even those that did not present visible corrosion spots, such stainless steel and copper alloys. Despite the presence or absence of corrosion at the later stages effectively by using the selective medium,, the initial stages of the corrosion could only be detected by the amplification of total DNA with SRB specific primers. The early detection of SRB could be employed for preventing the damages on metal surfaces before the installation of corrosion processes. Strategies for reducing the time spent on SRB isolation and identification could be auxiliary tools for controlling the corrosion of materials.

  16. Significant cooling effect on the surface due to soot particles over Brahmaputra River Valley region, India: An impact on regional climate.

    Science.gov (United States)

    Tiwari, S; Kumar, R; Tunved, P; Singh, S; Panicker, A S

    2016-08-15

    Black carbon (BC) is an important atmospheric aerosol constituent that affects the climate by absorbing (directly) the sunlight and modifying cloud characteristics (indirectly). Here, we present first time yearlong measurements of BC and carbon monoxide (CO) from an urban location of Guwahati located in the Brahmaputra River valley (BRV) in the northeast region of India from 1st July 2013 to 30th June 2014. Daily BC concentrations varied within the range of 2.86 to 11.56μgm(-3) with an annual average of 7.17±1.89μgm(-3), while, CO varied from 0.19 to 1.20ppm with a mean value of 0.51±0.19ppm during the study period. The concentrations of BC (8.37μgm(-3)) and CO (0.67ppm) were ~39% and ~55% higher during the dry months (October to March) than the wet months (April to September) suggesting that seasonal changes in meteorology and emission sources play an important role in controlling these species. The seasonal ΔBC/ΔCO ratios were highest (lowest) in the pre-monsoon (winter) 18.1±1.4μgm(-3)ppmv(-1) (12.6±2.2μgm(-3)ppmv(-1)) which indicate the combustion of biofuel/biomass as well as direct emissions from fossil fuel during the pre-monsoon season. The annual BC emission was estimated to be 2.72Gg in and around Guwahati which is about 44% lower than the mega city 'Delhi' (4.86Gg). During the study period, the annual mean radiative forcing (RF) at the top of the atmosphere (TOA) for clear skies of BC was +9.5Wm(-2), however, the RF value at the surface (SFC) was -21.1Wm(-2) which indicates the net warming and cooling effects, respectively. The highest RF at SFC was in the month of April (-30Wm(-2)) which is coincident with the highest BC mass level. The BC atmospheric radiative forcing (ARF) was +30.16 (annual mean) Wm(-2) varying from +23.1 to +43.8Wm(-2). The annual mean atmospheric heating rate (AHR) due to the BC aerosols was 0.86Kday(-1) indicates the enhancement in radiation effect over the study region. The Weather Research and Forecasting model

  17. 人体平衡机能增长敏感期和衰减明显期的研究%A Study on the Human Balance Function During the Period of Significant Growth and Reduce

    Institute of Scientific and Technical Information of China (English)

    任玉庆; 潘月红

    2012-01-01

    采用Tetrax平衡仪测试受试者双脚自然站立时一般稳定性指数(ST)、姿势摆动的频谱分析、体重分布、同步性指标;研究结果:男女性同性别不同年龄组之间平衡机能测试值无明显差异(P〉0.05);男女性平衡机能指标均呈现先增至某一峰值(15-17岁组),后逐渐减小趋势,增长敏感期和衰减明显期分别出现在15-17岁组之前和51-55岁组之后;5-14岁男性平衡机能指标明显优于女性,而46-60岁男性平衡能力指标差于同龄女性。结论:在5-17岁和46-60岁对机体进行适时合理的运动干预可更为有效地提高或改善人体平衡机能。%The general stability index, postural sway spectrum analyses, weight distribution and synchronizations were measured in standing position with eyes open using Tetrax balance system. Results: There were no significant differences in variables of balance in different age groups in the same sex ( P 〉 O. 05 ) ; The changes of townspeople balance function is increasing to some peak value ( 15 - 17 years old), then gradually reduced , the period of significant growth and reduce respectively appear in before 15 - 17 years old and after 51 -55 years old;The male balance function of 5 -14 years old is significantly higher than the female of the same age stage, but the male balance function after the female of the same age stage in 46 - 60 years old. Conclusion : The sensi- tive periods in 5 - 17 years old and 46 - 60 years old are able to more effectively provide for raising and minimizing the loss of balance.

  18. Significantly Reduced Genoprevalence of Vaccine-Type HPV-16/18 Infections among Vaccinated Compared to Non-Vaccinated Young Women 5.5 Years after a Bivalent HPV-16/18 Vaccine (Cervarix®) Pilot Project in Uganda.

    Science.gov (United States)

    Kumakech, Edward; Berggren, Vanja; Wabinga, Henry; Lillsunde-Larsson, Gabriella; Helenius, Gisela; Kaliff, Malin; Karlsson, Mats; Kirimunda, Samuel; Musubika, Caroline; Andersson, Sören

    2016-01-01

    The objective of this study was to determine the prevalence and some predictors for vaccine and non-vaccine types of HPV infections among bivalent HPV vaccinated and non-vaccinated young women in Uganda. This was a comparative cross sectional study 5.5 years after a bivalent HPV 16/18 vaccination (Cervarix®, GlaxoSmithKline, Belgium) pilot project in western Uganda. Cervical swabs were collected between July 2014-August 2014 and analyzed with a HPV genotyping test, CLART® HPV2 assay (Genomica, Madrid Spain) which is based on PCR followed by microarray for determination of genotype. Blood samples were also tested for HIV and syphilis infections as well as CD4 and CD8 lymphocyte levels. The age range of the participants was 15-24 years and mean age was 18.6(SD 1.4). Vaccine-type HPV-16/18 strains were significantly less prevalent among vaccinated women compared to non-vaccinated women (0.5% vs 5.6%, p 0.006, OR 95% CI 0.08(0.01-0.64). At type-specific level, significant difference was observed for HPV16 only. Other STIs (HIV/syphilis) were important risk factors for HPV infections including both vaccine types and non-vaccine types. In addition, for non-vaccine HPV types, living in an urban area, having a low BMI, low CD4 count and having had a high number of life time sexual partners were also significant risk factors. Our data concurs with the existing literature from other parts of the world regarding the effectiveness of bivalent HPV-16/18 vaccine in reducing the prevalence of HPV infections particularly vaccine HPV- 16/18 strains among vaccinated women. This study reinforces the recommendation to vaccinate young girls before sexual debut and integrate other STI particularly HIV and syphilis interventions into HPV vaccination packages.

  19. Chlorophyllin significantly reduces benzo[a]pyrene-DNA adduct formation and alters cytochrome P450 1A1 and 1B1 expression and EROD activity in normal human mammary epithelial cells.

    Science.gov (United States)

    Keshava, Channa; Divi, Rao L; Einem, Tracey L; Richardson, Diana L; Leonard, Sarah L; Keshava, Nagalakshmi; Poirier, Miriam C; Weston, Ainsley

    2009-03-01

    We hypothesized that chlorophyllin (CHLN) would reduce benzo[a]pyrene-DNA (BP-DNA) adduct levels. Using normal human mammary epithelial cells (NHMECs) exposed to 4 microM BP for 24 hr in the presence or absence of 5 microM CHLN, we measured BP-DNA adducts by chemiluminescence immunoassay (CIA). The protocol included the following experimental groups: BP alone, BP given simultaneously with CHLN (BP+CHLN) for 24 hr, CHLN given for 24 hr followed by BP for 24 hr (preCHLN, postBP), and CHLN given for 48 hr with BP added for the last 24 hr (preCHLN, postBP+CHLN). Incubation with CHLN decreased BPdG levels in all groups, with 87% inhibition in the preCHLN, postBP+CHLN group. To examine metabolic mechanisms, we monitored expression by Affymetrix microarray (U133A), and found BP-induced up-regulation of CYP1A1 and CYP1B1 expression, as well as up-regulation of groups of interferon-inducible, inflammation and signal transduction genes. Incubation of cells with CHLN and BP in any combination decreased expression of many of these genes. Using reverse transcription real time PCR (RT-PCR) the maximal inhibition of BP-induced gene expression, >85% for CYP1A1 and >70% for CYP1B1, was observed in the preCHLN, postBP+CHLN group. To explore the relationship between transcription and enzyme activity, the ethoxyresorufin-O-deethylase (EROD) assay was used to measure the combined CYP1A1 and CYP1B1 activities. BP exposure caused the EROD levels to double, when compared with the unexposed controls. The CHLN-exposed groups all showed EROD levels similar to the unexposed controls. Therefore, the addition of CHLN to BP-exposed cells reduced BPdG formation and CYP1A1 and CYP1B1 expression, but EROD activity was not significantly reduced.

  20. Research of Reducing the Surface's RCS by Using Active Periodical Structure%有源周期性结构缩减表面RCS的研究

    Institute of Scientific and Technical Information of China (English)

    周焱; 苏东林

    2011-01-01

    How to reduce Radar Cross Section(RCS) of aircraft's surface effectively is important and key issue at the field of research of aircraft steal.Structural absorb is proposed in this paper, using the periodical surface's character of band gap and impedance transition of electromagnetic crystal structure such as Photonic band gap and high impedance surface(HIS) and so on, to put single or multilayer periodical structure on the surface of the shell of aircraft, and to put the Varactor Diode onto the approximate HIS to join each cell of metal on top layer to realize the electronic control for periodical structure, will establish the active periodical structure.This structure could realize absorbing the exotic electromagnetic wave and restrain surface wave on it.The result of above process is reducing the RCS of the surface of aircraft effectively.The simulation test prove that this method and technology could reduce RCS 3~14 dB at working frequency band by using single or double layer active periodical structure, and reduce RCS 20 dB with the ideal condition of multilayer structure, and the working frequency band could be changed and controlled by electronic method also.%在飞行器隐身的研究中,如何有效地降低其表面雷达散射截面(RCS)是重点和研究热点.提出结构性吸收概念,利用如光带隙电磁结晶结构、高阻抗结构等周期性结构的带隙特性和阻抗特性,在物体表面设置单层或多层周期性结构,并通过在类似高阻抗表面的周期性金属单元表面铺设有源器件一变容二极管控制周期性结构的性能,从而实现对入射电磁波的吸收和对表面波的抑制,有效降低了机身表面的RCS.仿真实验证明采用单层或双层有源周期性结构表面,在周期性结构带隙频带内,可以将RCS减缩到3~14 dB,并在多层结构理想化优化条件下,达到缩减RCS 20dB以上,并且可以通过电控方法控制减缩RCS的频带范围.

  1. Reducing nitrogen losses through ammonia volatilization and surface runoff to improve apparent nitrogen recovery of double cropping of late rice using controlled release urea.

    Science.gov (United States)

    Li, Pengfei; Lu, Jianwei; Hou, Wenfeng; Pan, Yonghui; Wang, Yang; Khan, Muhammad Rizwan; Ren, Tao; Cong, Rihuan; Li, Xiaokun

    2017-04-01

    Controlled release fertilizer can reduce nitrogen losses to the environment while increasing grain yield and improving apparent nitrogen recovery (ANR) of rice. However, few studies have evaluated the comparative efficacy of different polymer-coated urea products on nitrogen (N) losses, ANR, and N uptake of rice. A 2-year field experiment was conducted to compare the effects of three different types of polymer-coated urea fertilizer on nitrogen losses through NH3 volatilization and surface runoff to the environment, ANR, grain yield, and N uptake as compared to conventional urea of rice. Six treatments including (1) control with 0 kg N ha(-1) (CK), (2) basal application of urea (Ub), (3) split application (Us) of urea (50% at transplanting, 25% at tillering, and 25% at panicle stages), (4) CRU-1 (polyurethane-coated urea), (5) CRU-2 (degradable polymer-coated urea), and (6) CRU-3 (water-based polymer-coated urea) all applied at 165 kg N ha(-1). It was found that CRU-2 resulted in the highest grain yield and panicle numbers among the N fertilization treatments in 2013 and 2014. Applying CRU could help increase N uptake in rice, reduce N losses through NH3 volatilization and surface runoff, and hence improve ANR. Its single dose can meet the nutrient demand of the rice plant. Controlled release urea could be adopted as an effective mitigation alternative to retard N losses through NH3 volatilization and surface runoff while improving ANR of double cropping of late rice.

  2. 血小板系列参数对血小板减少性疾病的临床意义%Clinical Significance of Platelet Parameters to the Diseases on Platelet Reduce

    Institute of Scientific and Technical Information of China (English)

    李瑞珍

    2014-01-01

    目的:探讨血小板系列参数对血小板减少性疾病的临床意义。方法采用SysmexXE-5000血液分析仪分别对200例健康体检者及200例血小板减少性患者的血小板平均体积( MPV)、血小板分布宽度( PDW)、大血小板比率( P-LCR)及血小板比容( PCT)进行测定。结果血小板减少性患者与血小板正常人群比较,其血小板平均体积( MPV)、血小板分布宽度( PDW)、大血小板比率( P-LCR)及血小板比容( PCT)有不同程度的升高、轻度降低或显著降低,差异均有统计学意义。结论血小板系列参数分析可作为某些血小板减少性疾病鉴别诊断的初筛指标,对某些血小板减少性疾病患者的诊断和治疗具有重要参考价值。%Objective To investigate the clinical significance of platelet parameters to the diseases on platelet reduce. Methods SysmexXE-5000 blood analyzer respectively in 200 healthy subjects and 200 patients with thrombocytopenia, platelet mean volume of patients (MPV), platelet distribution width (PDW), platelet large cell ratio (P-LCR) and hematocrit (PCT) were measured. Results The thrombocytopenia compared the normal population it’ platelet ( MPV, average volume, platelet dis-tribution width ( PDW) , platelet large cell ratio ( P-LCR) and hematocrit ( PCT) were slightly decreased or decreased significant-ly, the differences were statistically significant. Conclusion The platelet parameter analysis can be used for some thrombocytope-nia in differential diagnosis of disease screening index, which has important reference value for some thrombocytopenia of diagnosis and treatment.

  3. Giant cane (Arundo donax L.) can substitute traditional energy crops in producing energy by anaerobic digestion, reducing surface area and costs: A full-scale approach.

    Science.gov (United States)

    Corno, Luca; Lonati, Samuele; Riva, Carlo; Pilu, Roberto; Adani, Fabrizio

    2016-10-01

    Arundo donax L. (Giant cane) was used in a full-scale anaerobic digester (AD) plant (power of 380kWhEE) in partial substitution for corn to produce biogas and electricity. Corn substitution was made on a biomethane potential (BMP) basis so that A. donax L. after substitution accounted for 15.6% of the total mix-BMP (BMPmix) and corn for 66.6% BMPmix. Results obtained indicated that Giant cane was able to substitute for corn, reducing both biomass and electricity production costs, because of both higher biomass productivity (Mg total solid Ha(-1)) and lower biomass cost (€Ha(-1)). Total electricity biogas costs were reduced by 5.5%. The total biomass cost, the total surface area needed to produce the energy crop and the total cost of producing electricity can be reduced by 75.5%, 36.6% and 22%, by substituting corn completely with Giant cane in the mix fed to the full-scale plant.

  4. Medium-size droplets of methyl ricinoleate are reduced by cell-surface activity in the γ-decalactone production by Yarrowia lipolytica

    OpenAIRE

    Waché, Y.; Bergmark, K.; Courthaudon, J.-L.; Aguedo, Mario; Nicaud, J.-M.; Belin, J.-M.

    2000-01-01

    Size of methyl ricinoleate droplets during biotransformation into γ-decalactone by Yarrowia lipolytica was measured in both homogenized and non-homogenized media. In non-homogenized but shaken medium, droplets had an average volume surface diameter d 32 of 2.5 μm whereas it was 0.7 μm in homogenized and shaken medium. But as soon as yeast cells were inoculated, both diameters became similar at about 0.7 μm and did not vary significantly until the end of the culture. The growth of Y. lipolytic...

  5. Medium-size droplets of methyl ricinoleate are reduced by cell-surface activity in the gamma-decalactone production by Yarrowia lipolytica.

    Science.gov (United States)

    Waché, Y; Bergmark, K; Courthaudon, J L; Aguedo, M; Nicaud, J M; Belin, J M

    2000-03-01

    Size of methyl ricinoleate droplets during biotransformation into gamma-decalactone by Yarrowia lipolytica was measured in both homogenized and non-homogenized media. In non-homogenized but shaken medium, droplets had an average volume surface diameter d32 of 2.5 microm whereas it was 0.7 microm in homogenized and shaken medium. But as soon as yeast cells were inoculated, both diameters became similar at about 0.7 microm and did not vary significantly until the end of the culture. The growth of Y. lipolytica in both media was very similar except for the lag phase which was lowered in homogenized medium conditions.

  6. Improved photoelectrochemical activity of CaFe2O4/BiVO4 heterojunction photoanode by reduced surface recombination in solar water oxidation.

    Science.gov (United States)

    Kim, Eun Sun; Kang, Hyun Joon; Magesh, Ganesan; Kim, Jae Young; Jang, Ji-Wook; Lee, Jae Sung

    2014-10-22

    A bismuth vanadate photoanode was first fabricated by the metal-organic decomposition method and particles of calcium ferrite were electrophoretically deposited to construct a heterojunction photoanode. The characteristics of the photoanodes were investigated in photoelectrochemical water oxidation under simulated 1 sun (100 mW cm(-2)) irradiation. Relative to the pristine BiVO4 anode, the formation of the heterojunction structure of CaFe2O4/BiVO4 increased the photocurrent density by about 60%. The effect of heterojunction formation on the transfer of charge carriers was investigated using hydrogen peroxide as a hole scavenger. It was demonstrated that the heterojunction formation reduced the charge recombination on the electrode surface with little effect on bulk recombination. The modification with an oxygen evolving catalyst, cobalt phosphate (Co-Pi), was also beneficial for improving the efficiency of CaFe2O4/BiVO4 heterojunction photoanode mainly by increasing the stability.

  7. Phosphorus and Nitrogen Dual Doped and Simultaneously Reduced Graphene Oxide with High Surface Area as Efficient Metal-Free Electrocatalyst for Oxygen Reduction

    Directory of Open Access Journals (Sweden)

    Xiaochang Qiao

    2015-06-01

    Full Text Available A P, N dual doped reduced graphene oxide (PN-rGO catalyst with high surface area (376.20 m2·g−1, relatively high P-doping level (1.02 at. % and a trace amount of N (0.35 at. % was successfully prepared using a one-step method by directly pyrolyzing a homogenous mixture of graphite oxide (GO and diammonium hydrogen phosphate ((NH42HPO4 in an argon atmosphere, during which the thermal expansion, deoxidization of GO and P, N co-doping were realized simultaneously. The catalyst exhibited enhanced catalytic performances for oxygen reduction reaction (ORR via a dominated four-electron reduction pathway, as well as superior long-term stability, better tolerance to methanol crossover than that of commercial Pt/C catalyst in an alkaline solution.

  8. Formation of environmentally persistent free radicals as the mechanism for reduced catechol degradation on hematite-silica surface under UV irradiation.

    Science.gov (United States)

    Li, Hao; Pan, Bo; Liao, Shaohua; Zhang, Di; Xing, Baoshan

    2014-05-01

    Iron is rich in soils, and is recently reported to form stable complexes with organic free radicals, generating environmentally persistent free radicals (EPFRs). The observation may challenge the common viewpoint that iron is an effective catalyst to facilitate the degradation of various organic chemicals. But no study was specifically designed to investigate the possible inhibited degradation of organic chemicals because of the formation of EPFRs in dry environment. We observed that catechol degradation under UV irradiation was decreased over 20% in silica particles coated with 1% hematite in comparison to uncoated silica particles. Stabilized semiquinone or quinine and phenol radicals were involved in HMT-silica system. EPFR formation was thus the reason for the reduced catechol degradation on HMT-silica surface under UV irradiation at ambient temperature. EPFRs should be incorporated in the studies of organic contaminants geochemical behavior, and will be a new input in their environmental fate modeling.

  9. Reduction of mouse egg surface integrin alpha9 subunit (ITGA9) reduces the egg's ability to support sperm-egg binding and fusion.

    Science.gov (United States)

    Vjugina, Ulyana; Zhu, Xiaoling; Oh, Eugene; Bracero, Nabal J; Evans, Janice P

    2009-04-01

    The involvement of egg integrins in mammalian sperm-egg interactions has been controversial, with data from integrin inhibitor studies contrasting with evidence from knockouts showing that specific integrin subunits are not essential for fertility. An alpha(4)/alpha(9) (ITGA4/ITGA9) integrin subfamily member has been implicated in fertilization but not extensively examined, so we tested the following three hypotheses: 1) an ITGA4/ITGA9 integrin participates in sperm-egg interactions, 2) short-term acute knockdown by RNA interference of integrin subunits would result in a fertilization phenotype differing from that of chronic depletion via knockout, and 3) detection of a fertilization phenotype is sensitive to in vitro fertilization (IVF) assay conditions. We show that mouse and human eggs express the alpha(9) integrin subunit (ITGA9). RNA interference-mediated knockdown resulted in reduced levels of Itga9 mRNA and surface protein in mouse eggs. RNA interference attempts to knockdown ITGA9's likely beta partner, beta(1) (ITGB1), resulted in reduced Itgb1 mRNA but no reduction in ITGB1 surface protein. Therefore, studies using a function-blocking anti-ITGB1 antibody tested the hypothesis that ITGB1 participates in gamete interactions. Analyses of sperm-egg interactions with Itga9-knockdown eggs and anti-ITGB1 antibody-treated eggs in IVF assays using specific sperm:egg ratios revealed the following: 1) a reduction, but not complete loss, of sperm-egg binding and fusion was observed and 2) the reduction of sperm-egg binding and fusion was not detected in inseminations with high sperm:egg ratios. These data demonstrate that ITGA9 and ITGB1 participate in sperm-egg interactions but clearly are not the only molecules involved. This also shows that careful design of IVF parameters allows detection of deficiencies in gamete interactions.

  10. Study of the surface-enhanced Raman spectroscopy of residual impurities in hydroxylamine-reduced silver colloid and the effects of anions on the colloid activity.

    Science.gov (United States)

    Dong, Xiao; Gu, Huaimin; Liu, Fangfang

    2012-03-01

    The paper investigated the residual ions in hydroxylamine-reduced silver colloid (HRSC) and the relationship between the condition of HRSC and the enhanced mechanisms of this colloid. We also detected the SERS of MB and studied the effects of anions on the Raman signal. In the case of HRSC, the bands of residual ions diminish while the bands of Ag-anions increase gradually with increasing the concentrations of Cl(-) and NO(3)(-). It means the affinity of residual ions on the silver surface is weaker than that of Cl(-) and NO(3)(-) and the residual ions are replaced gradually by the added Cl(-) or NO(3)(-). The Raman signal of residual ions can be detected by treatment with anions that do not bind strongly to the silver surface, such as SO(4)(2-). The most intense band of Ag-anions bonds can be also observed when adding weakly binding anions to the colloid. However, the anions which make up the Ag-anions bonds are residual Cl(-) and the effect of weakly binding anions is only to aggregate the silver particles. Residual Cl(-) can be replaced by I(-) which has the highest affinity. From the detection of methylene blue (MB), the effects of anions on the enhancement of Raman signal are discussed in detail, and these findings could make the conditions suitable for detecting analytes in high efficiency. This study will have a profound implication to SERS users about their interpretation of SERS spectra when obtaining these anomalous bands.

  11. Increase globe artichoke cropping sustainability using sub-surface drip-irrigation systems in a Mediterranean coastal area for reducing groundwater withdrawal

    Science.gov (United States)

    Mantino, Alberto; Marchina, Chiara; Bonari, Enrico; Fabbrizzi, Alessandro; Rossetto, Rudy

    2017-04-01

    suitability of SDI for globe artichoke cultivation, reducing the water consumption, while maintaining (or even increasing) crop production and (ii) assess the crop water use efficiency respect to surface drip-irrigation. The field test is located in Venturina (Italy) and it covers a surface of 4 ha. The soil is characterized by sandy-loam texture, 1.72% of organic matter at 7.81 pH. Groundwater is the main source of supply for irrigation. By the chemical point of view, a monitoring campaign in spring 2016 showed a neutral pH of 7.2, electrical conductivity of 1363 μS/cm, 373 and 243 mg/l of total sulphate and carbonate, respectively, thus demonstrating the suitability of groundwater for SDI application. The SDI system was implemented at the beginning of September 2016. The sub-surface buried pipelines, were placed at 0.25 m depth, with emitters spaced 0.5 m. The distance between pipelines was 1.5 m, according to globe artichoke layout (1.5 m between rows, 1 m in-row spacing). Surface-buried tubes were placed in an area about 0.75 ha wide for the comparison with SDI. Artichoke var. Terom were transplanted after the SDI operation test. In the next 3 years, both crop productivity and water use will be assessed. Results will be presented and discussed with the whole farmer's community. Acknowledgement This paper is presented within the framework of the project LIFE REWAT, which has received funding from the LIFE Programme of the European Union Grant Agreement LIFE14 ENV/IT/001290.

  12. 风险管理模式降低医院护理不良事件的意义%Significance of Risk Management in Reducing the Hospital Nursing Adverse Events

    Institute of Scientific and Technical Information of China (English)

    张霞

    2016-01-01

    目的:探讨风险管理模式对降低医院护理不良事件的效果,为临床应用提供参考依据。方法随机选取该院12个不同护理单元,根据管理模式的不同分为研究组和对照组。研究组共6个护理单元,实施护理风险管理模式;对照组共6个护理单元,采用常规护理管理体制。比较两组护理不良事件发生率及护理人员安全意识改变情况。结果研究组2217例患者中,共发生10例给药错误、39例管路滑脱、15例坠床及0例走失,其护理不良事件发生率为2.89%;对照组2235例患者中,共发生42例给药错误、61例管路滑脱、38例坠床及3例走失,其护理不良事件发生率为6.44%;组间比较,差异有统计学意义(P attitude and risk management behavior intention were obviously higher than those before implementation, [(21.1±3.9), (21.5± 3.7), (21.9±3.4), (22.7±3.3) vs (15.3±7.4),(16.1±6.9),(15.1±5.9) (16.1±6.1)], and the differences had statistical significance, P<0.01. Conclusion The application of nursing risk management model in the hospital nursing management work can effectively reduce the occurrence of nursing adverse events, cultivate the safety awareness, risk awareness and anti-risk ability of nursing staff and make contributions to drawing near the doctor-nurse relationship and constructing a good hospital image, which is worth clinical promotion and application.

  13. 异化Fe(Ⅲ)还原菌及其还原机制的环境意义%Dissimilatory Fe( Ⅲ)-reducing Bacteria and the Environmental Significance of Its Reduction Mechanism

    Institute of Scientific and Technical Information of China (English)

    曾洪学; 杨玉泉; 屈兴红; 黄灿

    2012-01-01

    Dissimilatory Fe( IE)-reducing bacteria with the powerful metabolism function, the ability to adapt to the harsh environment and strong reduction function have great importance to the biological remediation of environment and play a decisive role in the eco-eycle of earth. They were capable of using Fe( HI) as the terminal electron acceptor coupled with many kinds of inorganic and organic matter transformation to gain energy under anoxic conditions. Microbial dissimilatory iron reduction has several significant environmental impacts. It can greatly influence the biogeochemical cycles of many metals and plays an important role in the flux of phosphate into water supplies. In addition, it has been proven to have a good application perspective in microbiology fuel batteries, odor control and protecting steel from corrosion. However, whether it is the basic study, or application study, research related to micmbial dissimilatory iron reduction is still close to the blank in China. According to the latest research advances both at home and abroad, the environmental significance of microbial dissimilatory iron reduction is reviewed to attract more attention of the researchers and accelerate this field study in our country.%异化Fe(Ⅲ)还原菌具有强大的代谢功能和适应恶劣环境的能力,其所具有的还原功能对于环境的生物修复具有重要的意义,在地球生态循环过程中具有举足轻重的作用.厌氧条件下,它可以Fe(Ⅲ)为末端电子受体,还原许多有毒重金属,降解利用有机和无机污染物,对土壤中痕量金属元素和磷的释放产生重要影响,在微生物燃料电池、环境除臭、防止钢铁腐蚀等方面有较好的应用前景和研究价值.当前无论是基础还是应用研究方面,国内微生物异化Fe(Ⅲ)还原菌的相关工作仍近空白.结合国外的最新研究进展,介绍了微生物异化Fe(Ⅲ)还原菌特性、还原机制及其还原的环境意义,旨在引起国内相

  14. Microbial dissolution of hematite and associated cellular fossilization by reduced iron phases: a study of ancient microbe-mineral surface interactions.

    Science.gov (United States)

    Kolo, Kamal; Konhauser, Kurt; Krumbein, Wolfgang Elisabeth; Ingelgem, Yves Van; Hubin, Annick; Claeys, Philippe

    2009-10-01

    We report here on magnetite- and wustite-encrusted and geometrically oriented microbial-like structures (MLS) attached to the surfaces of hematite (alpha-Fe(2)O(3)) crystals in a banded iron formation. Field emission scanning electron microscope (FE-SEM) and scanning electron microscope (SEM) imaging showed a 3-D network of MLS arranged in 1 microm x approximately 20 microm coccoidal-like chains (CLC) of various geometrical shapes: dichotomous and budding-like protrusions, parallel, intersecting, triangular, or sinusoidal. Individual spheroidal forms ( approximately 1 mum in diameter), some displaying what appears to be division, were also abundant. In addition to their size, morphology, and preferred orientations, a microbial origin of these chains and single spheroidal forms is inferred by the presence of material that resembles extracellular polymeric substances (EPS) extending from the base of the chains along the mineral surface: the attachment sites show circular dissolution pits of about 100 nm diameter. Other thin structures protruding from the CLC are reminiscent of bacterial "nanowires." We were, however, unable to find any extant cells, organic carbon, or even recover DNA from the MLS, which suggests that they, if microbial, are possibly mineralogically replaced casts or mineral encrustations of cells. It is further speculated that, given the nature of the substrate upon which the forms are attached and their preferential orientations, it seems plausible that the "original cells" may have been Fe(III)-reducing bacteria that exploited structural imperfections in the crystal lattice. Importantly, the preservation of the ancient microbial shapes in mineral casts of magnetite, wustite, or both may be an overlooked means by which cellular features in the rock record are retained.

  15. I. Measuring and Reducing Stress and Surface Roughness in IBAD MgO Films and II. Developing Tools to Measure Transfer in Undergraduate Chemistry Students

    Science.gov (United States)

    Antonakos, Cory Dale

    I. MgO may be grown with a biaxial texture onto an amorphous substrate with the use of ion beam assisted deposition (IBAD). This MgO film may then be used as a platform on which to grow epitaxial films on an amorphous membrane for characterization purposes. However, the IBAD MgO film is stressed, causing buckles in the amorphous membrane and problems with further film growth on the IBAD MgO. This dissertation work explores the source of this film stress and develops methods to relax the stress and reduce surface roughness with annealing and increased growth temperature. It is determined that annealing and increased growth temperature coupled with a higher ion-to-atom ratio (IAR) during film growth reduce stress and surface roughness sufficiently to use even thinner IBAD MgO films as an intermediate layer between an amorphous membrane and epitaxial film. II. Much of the existing literature on knowledge transfer concludes that transfer is rare and does not occur spontaneously. However, studies supporting that transfer is rare often use methods that focus on binary success or failure to solve a problem correctly and do not analyze thought process. This dissertation work aims at developing transfer questions that allow open-ended responses, developing a method of analysis for these responses that looks for transfer in the problem-solving process, and assessing the methodology itself and its sensitivity, validity, and utility as a general transfer measurement technique for use across a broad range of expertise levels in chemistry. Detailed analysis of responses to each transfer question show that some transfer questions are more effective at distinguishing between expertise levels while also allowing responders of all levels to show knowledge transfer. Simpler questions that are more accessible to students of introductory chemistry proved the most useful at eliciting a range of responses that correlate with expertise level while still showing some degree of transfer in

  16. A plan to reduce volatile organic compound emissions from consumer products in Canada (excluding windshield washer fluid and surface coatings) : final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-12-01

    This report highlights the recommendations made by the Canadian Council of Ministers of the Environment for the development of a guideline to provide a means by which to reduce (VOC) emissions from consumer products (excluding windshield washer fluid and surface coatings) in Canada. VOCs and nitrogen oxides react photochemically in the presence of sunlight to create ground-level ozone, a primary component of urban smog which has a detrimental effect on human health, agricultural crops and building materials. In recent years, most urban areas of Canada have shown an annual increase in the maximum acceptable air quality levels for ground level ozone. Reducing emissions of volatile organic compounds (VOCs) from consumer products was first suggested in 1990 by the Canadian Council of Ministers of the Environment in phase one of their program entitled the 'Management plan for nitrogen oxides and volatile organic compounds'. Phase 2 of the program was implemented in 1997 to harmonize the emissions reduction program with the United States Environmental Protection Agency regulations. The Canadian Environmental Protection Agency (CEPA) recommended the following control options: (1) a CEPA guideline should be developed which states the maximum VOC and high-volatility organic compound (HVOC) content in Canadian consumer products including hair care products, herbicides, insecticides, air fresheners, deodorants, fungicides, surface cleaners, fragrance products, anti-microbial agents, laundry products and automotive detailing products. These limits should be identical to those found in the 1998 U.S. Final Rule for Consumer Products, (2) the CEPA guideline should require that records specifying VOC content in weight-per cent be maintained for a period of three years, (3) the CEPA guideline should include a declaration procedure for Canadian importers and manufacturers of consumer products to report to Environment Canada regarding the VOC content of their products, and

  17. Controllable embedding of sulfur in high surface area nitrogen doped three dimensional reduced graphene oxide by solution drop impregnation method for high performance lithium-sulfur batteries

    Science.gov (United States)

    Zegeye, Tilahun Awoke; Tsai, Meng-Che; Cheng, Ju-Hsiang; Lin, Ming-Hsien; Chen, Hung-Ming; Rick, John; Su, Wei-Nien; Kuo, Chung-Feng Jeffrey; Hwang, Bing-Joe

    2017-06-01

    High capacity lithium-sulfur batteries with stable cycle performance and sulfur loadings greater than 70 wt% are regarded as promising candidates for energy storage devices. However, it has been challenged to achieving practical application of sulfur cathode because of low loading of active sulfur and poor cycle performance. Herein, we design novel nanocomposite cathode materials consist of sulfur (80 wt%) embedded within nitrogen doped three-dimensional reduced graphene oxide (N-3D-rGO) by controllable sulfur-impregnation method. Nitrogen doping helps increase the surface area by ten times from pristine graphene, and pore volume by seven times. These structural features allow the cathode to hold more sulfur. It also adsorbs polysulfides and prevents their detachment from the host materials; thereby achieving stable cycle performance. The solution drop sulfur-impregnation method provides uniform distribution of nano-sulfur in controlled manner. The material delivers a high initial discharge capacity of 1042 mAhg-1 and 916 mAhg-1 with excellent capacity retention of 94.8% and 81.9% at 0.2 C and 0.5 C respectively after 100 cycles. Thus, the combination of solution drop and nitrogen doping opens a new chapter for resolving capacity fading as well as long cycling problems and creates a new strategy to increase sulfur loading in controlled mechanism.

  18. High-resolution calculation of the solar global convection with the reduced speed of sound technique: II. Near surface shear layer with the rotation

    CERN Document Server

    Hotta, H; Yokoyama, T

    2014-01-01

    We present a high-resolution, highly stratified numerical simulation of rotating thermal convection in a spherical shell. Our aim is to study in detail the processes that can maintain a near surface shear layer (NSSL) as inferred from helioseismology. Using the reduced speed of sound technique we can extend our global convection simulation to $0.99\\,R_{\\odot}$ and include near the top of our domain small-scale convection with short time scales that is only weakly influenced by rotation. We find the formation of a NSSL preferentially in high latitudes in the depth range $r=0.95-0.975R_\\odot$. The maintenance mechanisms are summarized as follows. Convection under weak influence of rotation leads to Reynolds stresses that transport angular momentum radially inward in all latitudes. This leads to the formation of a strong poleward directed meridional flow and a NSSL, which is balanced in the meridional plane by forces resulting from the $\\langle v'_r v'_\\theta\\rangle$ correlation of turbulent velocities. The orig...

  19. High-resolution Calculation of the Solar Global Convection with the Reduced Speed of Sound Technique. II. Near Surface Shear Layer with the Rotation

    Science.gov (United States)

    Hotta, H.; Rempel, M.; Yokoyama, T.

    2015-01-01

    We present a high-resolution, highly stratified numerical simulation of rotating thermal convection in a spherical shell. Our aim is to study in detail the processes that can maintain a near surface shear layer (NSSL) as inferred from helioseismology. Using the reduced speed of sound technique, we can extend our global convection simulation to 0.99 R ⊙ and include, near the top of our domain, small-scale convection with short timescales that is only weakly influenced by rotation. We find the formation of an NSSL preferentially in high latitudes in the depth range of r = 0.95-0.975 R ⊙. The maintenance mechanisms are summarized as follows. Convection under the weak influence of rotation leads to Reynolds stresses that transport angular momentum radially inward in all latitudes. This leads to the formation of a strong poleward-directed meridional flow and an NSSL, which is balanced in the meridional plane by forces resulting from the correlation of turbulent velocities. The origin of the required correlations depends to some degree on latitude. In high latitudes, a positive correlation is induced in the NSSL by the poleward meridional flow whose amplitude increases with the radius, while a negative correlation is generated by the Coriolis force in bulk of the convection zone. In low latitudes, a positive correlation results from rotationally aligned convection cells ("banana cells"). The force caused by these Reynolds stresses is in balance with the Coriolis force in the NSSL.

  20. Local cooling reduces skin ischemia under surface pressure in rats: an assessment by wavelet analysis of laser Doppler blood flow oscillations.

    Science.gov (United States)

    Jan, Yih-Kuen; Lee, Bernard; Liao, Fuyuan; Foreman, Robert D

    2012-10-01

    The objectives of this study were to investigate the effects of local cooling on skin blood flow response to prolonged surface pressure and to identify associated physiological controls mediating these responses using the wavelet analysis of blood flow oscillations in rats. Twelve Sprague-Dawley rats were randomly assigned to three protocols, including pressure with local cooling (Δt = -10 °C), pressure with local heating (Δt = 10 °C) and pressure without temperature changes. Pressure of 700 mmHg was applied to the right trochanter area of rats for 3 h. Skin blood flow was measured using laser Doppler flowmetry. The 3 h loading period was divided into non-overlapping 30 min epochs for the analysis of the changes of skin blood flow oscillations using wavelet spectral analysis. The wavelet amplitudes and powers of three frequencies (metabolic, neurogenic and myogenic) of skin blood flow oscillations were calculated. The results showed that after an initial loading period of 30 min, skin blood flow continually decreased under the conditions of pressure with heating and of pressure without temperature changes, but maintained stable under the condition of pressure with cooling. Wavelet analysis revealed that stable skin blood flow under pressure with cooling was attributed to changes in the metabolic and myogenic frequencies. This study demonstrates that local cooling may be useful for reducing ischemia of weight-bearing soft tissues that prevents pressure ulcers.

  1. Rumble surfaces

    CSIR Research Space (South Africa)

    National Institute for Transport and Road

    1977-01-01

    Full Text Available Rumble surfaces are intermittent short lengths of coarse-textured road surfacings on which vehicle tyres produce a rumbling sound. used in conjunction with appropriate roadsigns and markings, they can reduce accidents on rural roads by alerting...

  2. Electrodeposited reduced graphene oxide incorporating polymerization of l-lysine on electrode surface and its application in simultaneous electrochemical determination of ascorbic acid, dopamine and uric acid.

    Science.gov (United States)

    Zhang, Dongdong; Li, Lingzhi; Ma, Weina; Chen, Xia; Zhang, Yanmin

    2017-01-01

    This paper demonstrates a novel strategy for the construction of a graphene hybrid composites film, which was fabricated by electrodeposited reduced graphene oxide (ERGO) incorporating polymerization of l-lysine (PLL) onto glassy carbon electrode (GCE). Here we show that graphene films can be prepared on electrodes directly from GO dispersions by one-step electrodeposition technique based on electropolymerized PLL as a positively charged polymer interface to adsorb negatively charged GO nanosheets through electrostatic attraction. The thickness of graphene film can be easily controlled by using the electrodeposition technique, a distinct advantage over previously developed methods. The electrochemically reduced process of GO and electropolymerization of l-lysine were investigated by cyclic voltammetry with a wide potential range. The surface morphology of the modified electrode was characterized by scanning electron microscopy. The ERGO/PLL/GCE shows conducive to electron transfer kinetics for Fe(CN)6(3-)/Fe(CN)6(4-) redox probes, compared with bare GCE, PLL/GCE and ERGO/GCE. The electrochemical behaviors of ascorbic acid (AA), dopamine (DA) and uric acid (UA) at ERGO/PLL/GCE were investigated by cyclic voltammetry, and the results suggest that the modified electrode exhibits enhanced electrocatalytic activity toward these important molecules. Under physiological condition and in the co-existence system of AA, DA and UA, the ERGO/PLL/GCE showed linear voltammetric responses in the concentration of 100μM-1200μM for AA, 2.0μM-60μM for DA and 20μM-200μM for UA, and with the detection limits (S/N=3) of 2.0μM, 0.10μM and 0.15μM for AA, DA and UA, respectively. The developed method has been applied to simultaneous determination of AA, DA and UA in human urine with satisfactory recoveries of 104.2%, 95.4% and 99.9%, respectively. This work demonstrates that the attractive features of ERGO/PLL provide promising applications in simultaneous determination of AA, DA

  3. Redox-dependent interactions between reduced/oxidized cytochrome c and cytochrome c oxidase evaluated by in-situ electrochemical surface plasmon resonance.

    Science.gov (United States)

    Hou, Yuting; An, Jianhong; Deng, Chunyan; Chen, Shu; Xiang, Juan

    2016-07-01

    The interactions between the redox couple of cytochrome c (Cyt c) and cytochrome c oxidase (COX) were investigated at a mimic redox-modulated interface by using an electrochemical surface plasmon resonance (EC-SPR) system. Although early studies of the binding between COX and Cyt c have been conducted using several techniques in homogeneous solutions, a problem still inherent is that ferro-cytochrome c (Cyt c red), the reduced form of Cyt c, can be easily oxidized into ferri-cytochrome c (Cyt c ox) and adversely impact the accuracy and reproducibility of the binding measurements. In order to realize reliable redox-dependent binding tests, here the Cyt c red is quantitatively electro-generated from Cyt c ox by in situ cathodic polarization in a flow cell. Then the kinetic and dissociation constants of the bindings between COX and Cyt c red/Cyt c ox can be evaluated accurately. In this study, the values of association/dissociation rate constants (k a, k d) for both COX/Cyt c red and COX/Cyt c ox were obtained. The dissociation constants, K D, were finally calculated as 3.33 × 10(-8) mol · L(-1) for COX/Cyt c red and 4.25 × 10(-5) mol · L(-1) for COX/Cyt c ox, respectively. In-situ EC-SPR is promising for better mimicking the in vivo condition that COX is embedded in the inner mitochondrial membrane and Cyt c acts as an electron shuttle in the mobile phase. It is an effective method for the investigation of redox-dependent biomolecular interactions. Graphical Abstract Schematic representation of the experimental designs using EC-SPR system. (a) the Au-Cys-COX SPR chip with SAM layers. (b) redox-modulated Cyt c and its binding onto pre-immobilized COX.

  4. HIGH-RESOLUTION CALCULATION OF THE SOLAR GLOBAL CONVECTION WITH THE REDUCED SPEED OF SOUND TECHNIQUE. II. NEAR SURFACE SHEAR LAYER WITH THE ROTATION

    Energy Technology Data Exchange (ETDEWEB)

    Hotta, H.; Rempel, M. [High Altitude Observatory, National Center for Atmospheric Research, Boulder, CO (United States); Yokoyama, T., E-mail: hotta@ucar.edu [Department of Earth and Planetary Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2015-01-01

    We present a high-resolution, highly stratified numerical simulation of rotating thermal convection in a spherical shell. Our aim is to study in detail the processes that can maintain a near surface shear layer (NSSL) as inferred from helioseismology. Using the reduced speed of sound technique, we can extend our global convection simulation to 0.99 R {sub ☉} and include, near the top of our domain, small-scale convection with short timescales that is only weakly influenced by rotation. We find the formation of an NSSL preferentially in high latitudes in the depth range of r = 0.95-0.975 R {sub ☉}. The maintenance mechanisms are summarized as follows. Convection under the weak influence of rotation leads to Reynolds stresses that transport angular momentum radially inward in all latitudes. This leads to the formation of a strong poleward-directed meridional flow and an NSSL, which is balanced in the meridional plane by forces resulting from the 〈v{sub r}{sup ′}v{sub θ}{sup ′}〉 correlation of turbulent velocities. The origin of the required correlations depends to some degree on latitude. In high latitudes, a positive correlation 〈v{sub r}{sup ′}v{sub θ}{sup ′}〉 is induced in the NSSL by the poleward meridional flow whose amplitude increases with the radius, while a negative correlation is generated by the Coriolis force in bulk of the convection zone. In low latitudes, a positive correlation 〈v{sub r}{sup ′}v{sub θ}{sup ′}〉 results from rotationally aligned convection cells ({sup b}anana cells{sup )}. The force caused by these Reynolds stresses is in balance with the Coriolis force in the NSSL.

  5. Discussion on Significance and Countermeasures of Reducing Sugar Content in Chinese Medicine%浅论中药制剂含糖比例降低的意义与对策

    Institute of Scientific and Technical Information of China (English)

    许红莉; 彭瑞松

    2014-01-01

    Sugar is extremely widely used in Chinese medicine, mainly as corrigents, excipients and antiseptics. In recent years, the rationality and necessity of using sugar as recipes in medicine (especially Chinese medicine) has come under questions. This article, base on related documents and daily work practice, gives a systematic survey on the pros and cons of sugar applied in Chinese medicine, the signiifcance of reducing sugar content (including the inlfuence of sugar on human health, efifcacy and quality of medicine), and the countermeasures for reducing sugar content, aims to promote scientiifc rational application of sugar in clinical Chinese medicine.%糖在中药制剂中有着极广泛的用途,主要用作矫味剂、赋形剂和防腐剂。近年来,药品中(尤其中药制剂)以大量蔗糖作为辅料的合理性和必要性备受质疑,本文结合相关资料和日常工作实践,就中药剂中糖的利弊、降低含糖量的意义(包括糖对人体健康的影响,糖对药剂疗效的影响,糖对制剂质量的影响)、以及降低含糖比例的对策进行系统概述,旨在促进糖在临床中药制剂中的科学合理应用。

  6. Histomorphometric Assessment of Cancellous and Cortical Bone Material Distribution in the Proximal Humerus of Normal and Osteoporotic Individuals: Significantly Reduced Bone Stock in the Metaphyseal and Subcapital Regions of Osteoporotic Individuals.

    Science.gov (United States)

    Sprecher, Christoph M; Schmidutz, Florian; Helfen, Tobias; Richards, R Geoff; Blauth, Michael; Milz, Stefan

    2015-12-01

    Osteoporosis is a systemic disorder predominantly affecting postmenopausal women but also men at an advanced age. Both genders may suffer from low-energy fractures of, for example, the proximal humerus when reduction of the bone stock or/and quality has occurred.The aim of the current study was to compare the amount of bone in typical fracture zones of the proximal humerus in osteoporotic and non-osteoporotic individuals.The amount of bone in the proximal humerus was determined histomorphometrically in frontal plane sections. The donor bones were allocated to normal and osteoporotic groups using the T-score from distal radius DXA measurements of the same extremities. The T-score evaluation was done according to WHO criteria. Regional thickness of the subchondral plate and the metaphyseal cortical bone were measured using interactive image analysis.At all measured locations the amount of cancellous bone was significantly lower in individuals from the osteoporotic group compared to the non-osteoporotic one. The osteoporotic group showed more significant differences between regions of the same bone than the non-osteoporotic group. In both groups the subchondral cancellous bone and the subchondral plate were least affected by bone loss. In contrast, the medial metaphyseal region in the osteoporotic group exhibited higher bone loss in comparison to the lateral side.This observation may explain prevailing fracture patterns, which frequently involve compression fractures and certainly has an influence on the stability of implants placed in this medial region. It should be considered when planning the anchoring of osteosynthesis materials in osteoporotic patients with fractures of the proximal humerus.

  7. IGOB131, a novel seed extract of the West African plant Irvingia gabonensis, significantly reduces body weight and improves metabolic parameters in overweight humans in a randomized double-blind placebo controlled investigation

    Directory of Open Access Journals (Sweden)

    Mbofung Carl MF

    2009-03-01

    Full Text Available Abstract Background A recent in vitro study indicates that IGOB131, a novel seed extract of the traditional West African food plant Irvingia gabonensis, favorably impacts adipogenesis through a variety of critical metabolic pathways including PPAR gamma, leptin, adiponectin, and glycerol-3 phosphate dehydrogenase. This study was therefore aimed at evaluating the effects of IGOB131, an extract of Irvingia gabonensis, on body weight and associated metabolic parameters in overweight human volunteers. Methods The study participants comprised of 102 healthy, overweight and/or obese volunteers (defined as BMI > 25 kg/m2 randomly divided into two groups. The groups received on a daily basis, either 150 mg of IGOB131 or matching placebo in a double blinded fashion, 30–60 minutes before lunch and dinner. At baseline, 4, 8 and 10 weeks of the study, subjects were evaluated for changes in anthropometrics and metabolic parameters to include fasting lipids, blood glucose, C-reactive protein, adiponectin, and leptin. Results Significant improvements in body weight, body fat, and waist circumference as well as plasma total cholesterol, LDL cholesterol, blood glucose, C-reactive protein, adiponectin and leptin levels were observed in the IGOB131 group compared with the placebo group. Conclusion Irvingia gabonensis administered 150 mg twice daily before meals to overweight and/or obese human volunteers favorably impacts body weight and a variety of parameters characteristic of the metabolic syndrome. This is the first double blind randomized placebo controlled clinical trial regarding the anti-obesity and lipid profile modulating effects of an Irvingia gabonensis extract. The positive clinical results, together with our previously published mechanisms of gene expression modulation related to key metabolic pathways in lipid metabolism, provide impetus for much larger clinical studies. Irvingia gabonensis extract may prove to be a useful tool in dealing with the

  8. Phytolith characteristics and their significance of environment in surface soils from wetlands of Changbai Shan area%长白山区湿地表土植硅体特征及其环境意义

    Institute of Scientific and Technical Information of China (English)

    郭梅娥; 李楠楠; 介冬梅; 葛勇; 王婷; 李荣麟; 王刘奎; 王培明; 刘洪妍; 刘利丹

    2012-01-01

    Wetlands play an important role in the global environmental change, and phytolith analysis in surface soil of wetlands is a basis for reconstructing the palaeoenvironment in the Quaternary. In this paper, surface soil phytoliths were analyzed in six wetlands from Huanan to Hani in Changbai Shan area. The results show that the phytolith assemblages in all wetlands surface soil samples except for Shalan are similar. Elongate, crenate, rondel and point-shaped phytoliths are dominant, which reveals the cold climate. PCA and cluster analysis are used to find the environmental significance of the phytoliths assemblages in different wetlands surface soils. The results indicate that temperature is the chief factor to control the otherness of phytoliths assemblages in wetlands in Changbai Shan area, at the same time, the types and percentages of phytoliths are closely related to the plants, humidity and elevation in the sample sites. Combining difference analysis with the change trend analysis in phytolith dimension, we can find that the width and length of bicrenate, polycrenate and crenate sinuate as well as the length of elongate psilate, the length of ridge and the height in rondel hipped and width of the point-shaped phytoliths exist significant difference and increase with the temperature. In sum, the phytolith morphotypes in all the sites are similar, but differences in the warm index and the size of the phytoliths are obvious. The result reveals that the phytolith assemblages and the size are sensitive to temperature change.%湿地在全球环境变化中扮演着十分重要的角色,湿地表土中的植硅体分析是恢复第四纪古环境的重要途径.文中选取长白山区的桦南到哈尼一线的6处湿地表土,并采用PCA和CA分析植硅体组合的环境指示意义,结果显示:温度因子是造成长白山不同湿地表土植硅体组合差异的第1环境因子,且植硅体的种类和含量与采样点上覆植被、湿度与海拔等环境

  9. Study on significance of application of dexmedetomidine in reducing agitation and throat pain in patients after general anesthesia%右美托咪定预防全麻术后躁动和咽喉疼痛的作用

    Institute of Scientific and Technical Information of China (English)

    钟剑平; 何绍旋

    2014-01-01

    time,extubation time and postoperative sore throat werecomparedbetweenbothgroups.Results Therestorationofspontaneousbreathingtimeandextubationtimehadbeencomparedbetweenthese two groups,the difference was not statistically significant( P ﹥0. 05). In postoperative agitation,53 cases in observation group with grade 0,agi-tation rate was 7. 02%;and 34 patients in control group with grade 0,the agitation rate was 40. 35%. Agitation in observation group was signifi-cantly lower than that of control group( P ﹤0. 05). In postoperative sore throat,46 cases in observation group with grade 0,rate of throat pain was 19. 30%;and 30 cases in control group with grade 0,throat pain rate was 47. 37%. The rate of throat pain in observation group was signifi-cantlylowerthanthatofcontrolgroup(P﹤0.05).Conclusion Dexmedetomidinehasagoodpreventiveeffectonagitationandthroatpainafter general anesthesia,and it also does not increase the risk of respiratory depression,hence it is worthy to be used for clinical application.

  10. Carbon 1s photoemission line analysis of C-based adsorbate on (111)In2O3 surface: The influence of reducing and oxidizing conditions

    Science.gov (United States)

    Brinzari, V.; Cho, B. K.; Korotcenkov, G.

    2016-12-01

    Synchrotron radiation photoemission study of C 1s line of (111) In2O3 surface was carried out under HV (high vacuum) doses of oxygen, carbon monoxide and water. Gas interaction with the surface was activated by heating of In2O3 monocrystalline film at temperatures of 160 or 250 °C. The study of complex structure of C 1 s line and evolution of its fine components allowed to establish their nature and to propose possible surface adsorbed species and reactions, including a direct chemisorption and dissociation of CO molecules. Reduction or oxidation of the surface determines whether the first (chemisorption) or the second (dissociation) process takes place. The latter is responsible for additional formation of ionosorbed oxygen. Both processes have not been previously reported for In2O3 and for conductive metal oxides.

  11. Low-intensity electromagnetic irradiation of 70.6 and 73 GHz frequencies enhances the effects of disulfide bonds reducer on Escherichia coli growth and affects the bacterial surface oxidation-reduction state.

    Science.gov (United States)

    Torgomyan, Heghine; Trchounian, Armen

    2011-10-14

    Low-intensity electromagnetic irradiation (EMI) of 70.6 and 73 GHz frequencies (flux capacity - 0.06 mW cm(-2)) had bactericidal effects on Escherichia coli. This EMI (1h) exposure suppressed the growth of E. coli K-12(λ). The pH value (6.0-8.0) did not significantly affect the growth. The lag-phase duration was prolonged, and the growth specific rate was inhibited, and these effects were more noticeable after 73 GHz irradiation. These effects were enhanced by the addition of DL-dithiothreitol (DTT), a strong reducer of disulfide bonds in surface membrane proteins, which in its turn also has bactericidal effect. Further, the number of accessible SH-groups in membrane vesicles was markedly decreased by EMI that was augmented by N,N'-dicyclohexycarbodiimide and DTT. These results indicate a change in the oxidation-reduction state of bacterial cell membrane proteins that could be the primary membranous mechanism in the bactericidal effects of low-intensity EMI of the 70.6 and 73 GHz frequencies.

  12. Non-inferiority of pulsed xenon UV light versus bleach for reducing environmental Clostridium difficile contamination on high-touch surfaces in Clostridium difficile infection isolation rooms

    National Research Council Canada - National Science Library

    Ghantoji, Shashank S; Stibich, Mark; Stachowiak, Julie; Cantu, Sherry; Adachi, Javier A; Raad, Issam I; Chemaly, Roy F

    2015-01-01

    ... % of sodium hypochlorite. Pulsed xenon UV light (PX-UV) is a means of quickly producing germicidal UV that has been shown to be effective in reducing environmental contamination by C. difficile spores...

  13. Surface modification and deuterium retention in reduced-activation steels under low-energy deuterium plasma exposure. Part II: steels pre-damaged with 20 MeV W ions and high heat flux

    Science.gov (United States)

    Ogorodnikova, O. V.; Zhou, Z.; Sugiyama, K.; Balden, M.; Pintsuk, G.; Gasparyan, Yu.; Efimov, V.

    2017-03-01

    The reduced-activation ferritic/martensitic (RAFM) steels including Eurofer (9Cr) and oxide dispersion strengthened (ODS) steels by the addition of Y2O3 particles investigated in Part I were pre-damaged either with 20 MeV W ions at room temperature at IPP (Garching) or with high heat flux at FZJ (Juelich) and subsequently exposed to low energy (~20-200 eV per D) deuterium (D) plasma up to a fluence of 2.9  ×  1025 D m-2 in the temperature range from 290 K to 700 K. The pre-irradiation with 20 MeV W ions at room temperature up to 1 displacement per atom (dpa) has no noticeable influence on the steel surface morphology before and after the D plasma exposure. The pre-irradiation with W ions leads to the same concentration of deuterium in all kinds of investigated steels, regardless of the presence of nanoparticles and Cr content. It was found that (i) both kinds of irradiation with W ions and high heat flux increase the D retention in steels compared to undamaged steels and (ii) the D retention in both pre-damaged and undamaged steels decreases with a formation of surface roughness under the irradiation of steels with deuterium ions with incident energy which exceeds the threshold of sputtering. The increase in the D retention in RAFM steels pre-damaged either with W ions (damage up to ~3 µm) or high heat flux (damage up to ~10 µm) diminishes with increasing the temperature. It is important to mention that the near surface modifications caused by either implantation of high energy ions or a high heat flux load, significantly affect the total D retention at low temperatures or low fluences but have a negligible impact on the total D retention at elevated temperatures and high fluences because, in these cases, the D retention is mainly determined by bulk diffusion.

  14. HBV replication is significantly reduced by IL-6

    Directory of Open Access Journals (Sweden)

    Jeng King-Song

    2009-04-01

    Full Text Available Abstract Interleukin-6 (IL-6 is a pleiotropic cytokine with pivotal functions in the regulation of the biological responses of several target cells including hepatocytes. The level of serum IL-6 has been reported to be elevated in patients with chronic hepatitis B, cirrhosis and hepatocellular carcinoma and represents the best marker of HBV-related clinical progression as compared with several other cytokines. In this study, we found that IL-6 was able to effectively suppress hepatitis B virus (HBV replication and prevent the accumulation of HBV covalently closed circular DNA (cccDNA in a human hepatoma cell line. We also demonstrated that the suppression of HBV replication by IL-6 requires concurrently a moderate reduction of viral transcripts/core proteins and a marked decrease in viral genome-containing nucleocapsids. Studies on the stability of existing viral capsids suggest that the IL-6 effect on the reduction of genome-containing nucleocapsids is mediated through the prevention of the formation of genome-containing nucleocapsids, which is similar to the effect of interferons. However, IFN-α/β and IFN-γ did not participate in the IL-6-induced suppression of HBV replication. Taken together, our results will provide important information to better understand the role of IL-6 in the course of HBV infection.

  15. RDX-based nanocomposite microparticles for significantly reduced shock sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Qiu Hongwei, E-mail: hqiu@stevens.edu [Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, NJ 07030 (United States); Stepanov, Victor; Di Stasio, Anthony R. [U.S. Army - Armament Research, Development, and Engineering Center, Picatinny, NJ 07806 (United States); Chou, Tsengming; Lee, Woo Y. [Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, NJ 07030 (United States)

    2011-01-15

    Cyclotrimethylenetrinitramine (RDX)-based nanocomposite microparticles were produced by a simple, yet novel spray drying method. The microparticles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and high performance liquid chromatography (HPLC), which shows that they consist of small RDX crystals ({approx}0.1-1 {mu}m) uniformly and discretely dispersed in a binder. The microparticles were subsequently pressed to produce dense energetic materials which exhibited a markedly lower shock sensitivity. The low sensitivity was attributed to small crystal size as well as small void size ({approx}250 nm). The method developed in this work may be suitable for the preparation of a wide range of insensitive explosive compositions.

  16. Significantly reducing registration time in IGRT using graphics processing units

    DEFF Research Database (Denmark)

    Noe, Karsten Østergaard; Denis de Senneville, Baudouin; Tanderup, Kari

    2008-01-01

    Purpose/Objective For online IGRT, rapid image processing is needed. Fast parallel computations using graphics processing units (GPUs) have recently been made more accessible through general purpose programming interfaces. We present a GPU implementation of the Horn and Schunck method...... respiration phases in a free breathing volunteer and 41 anatomical landmark points in each image series. The registration method used is a multi-resolution GPU implementation of the 3D Horn and Schunck algorithm. It is based on the CUDA framework from Nvidia. Results On an Intel Core 2 CPU at 2.4GHz each...... registration took 30 minutes. On an Nvidia Geforce 8800GTX GPU in the same machine this registration took 37 seconds, making the GPU version 48.7 times faster. The nine image series of different respiration phases were registered to the same reference image (full inhale). Accuracy was evaluated on landmark...

  17. Insecticide-treated bed nets reduce plasma antibody levels and limit the repertoire of antibodies to Plasmodium falciparum variant surface antigens

    DEFF Research Database (Denmark)

    Askjaer, N; Maxwell, C; Chambo, W

    2001-01-01

    variant surface antigens (VSA) are important in the development of naturally acquired immunity to Plasmodium falciparum malaria and may thus be good indicators of immune status. We have compared the levels of VSA antibodies in plasma from children who have used ITN for 4 years to levels in plasma from...

  18. Using tree ring data as a proxy for transpiration to reduce predictive uncertainty of a model simulating groundwater–surface water–vegetation interactions

    OpenAIRE

    Schilling, O. S; Doherty, J; KINZELBACH, W.; Wang, H; Yang, P. N; Brunner, Philip

    2017-01-01

    Summary The interactions between surface water, the vadose zone, groundwater, and vegetation are governed by complex feedback mechanisms. Numerical models simulating these interactions are essential in quantifying these processes. However, the notorious lack of field observations results in highly uncertain parameterizations. We suggest a new type of observation data to be included in the calibration data set for hydrological models simulating interactions with vegetation: Tree rings as ...

  19. Design Strategies for CeO2-MoO3 Catalysts for DeNOx and Hg(0) Oxidation in the Presence of HCl: The Significance of the Surface Acid-Base Properties.

    Science.gov (United States)

    Chang, Huazhen; Wu, Qingru; Zhang, Tao; Li, Mingguan; Sun, Xiaoxu; Li, Junhua; Duan, Lei; Hao, Jiming

    2015-10-20

    A series of CeMoOx catalysts with different surface Ce/Mo ratios was synthesized by a coprecipitation method via changing precipitation pH value. The surface basicity on selective catalytic reduction (SCR) catalysts (CeMoOx and VMo/Ti) was characterized and correlated to the durability and activity of catalyst for simultaneous elimination of NOx and Hg(0). The pH value in the preparation process affected the surface concentrations of Ce and Mo, the Brunauer-Emmett-Teller (BET) specific surface area, and the acid-base properties over the CeMoOx catalysts. The O 1s X-ray photoelectron spectroscopy (XPS) spectra and CO2-temperature programmed desorption (TPD) suggested that the surface basicity increased as the pH value increased. The existence of strong basic sites contributed to the deactivation effect of HCl over the VMo/Ti and CeMoOx catalysts prepared at pH = 12. For the CeMoOx catalysts prepared at pH = 9 and 6, the appearance of surface molybdena species replaced the surface -OH, and the existence of appropriate medium-strength basic sites contributed to their resistance to HCl poisoning in the SCR reaction. Moreover, these sites facilitated the adsorption and activation of HCl and enhanced Hg(0) oxidation. On the other hand, the inhibitory effect of NH3 on Hg(0) oxidation was correlated with the competitive adsorption of NH3 and Hg(0) on acidic surface sites. Therefore, acidic surface sites may play an important role in Hg(0) adsorption. The characterization and balance of basicity and acidity of an SCR catalyst is believed to be helpful in preventing deactivation by acid gas in the SCR reaction and simultaneous Hg(0) oxidation.

  20. Local cooling reduces skin ischemia under surface pressure in rats: an assessment by wavelet analysis of laser Doppler blood flow oscillations

    OpenAIRE

    Jan, Yih-Kuen; Lee, Bernard; Liao, Fuyuan; Foreman, Robert D.

    2012-01-01

    The objectives of this study were to investigate the effects of local cooling on skin blood flow response to prolonged surface pressure and to identify associated physiological controls mediating these responses using wavelet analysis of blood flow oscillations in rats. Twelve Sprague Dawley rats were randomly assigned into three protocols, including pressure with local cooling (Δt= −10°C), pressure with local heating (Δt= 10°C), and pressure without temperature changes. Pressure of 700 mmHg ...

  1. Generation of the J/sub c/, H/sub c/, T/sub c/ surface for commercial superconductor using reduced-state parameters

    Energy Technology Data Exchange (ETDEWEB)

    Green, M.A.

    1988-04-01

    This report presents a method for calculating the J/sub C/, H/sub C/, T/sub C/ surface for Type II Superconductors. The method requires that one knows T/sub C/ at zero current and field, H/sub c2/ at zero current and temperature, and J/sub c/ at at least one temperature and field. The theory presented in this report agrees with the measured data quite well over virtually the entire J/sub c/, H/sub c/, T/sub c/ surface given the value of J/sub c/ versus H at one or two temperatures. This report presents calculated and measured values of J/sub c/ versus T and B for niobium titanium, niobium zirconium, niobium tin, niobium titanium tin, niobium tantalum tin, vanadium zirconium hafnium, and vanadium gallium. Good agreement of theory with measured data was obtained for commercial niobium titanium and niobium tin. 76 refs., 26 figs., 6 tabs.

  2. Bacteria can form interconnected microcolonies when a self-excreted product reduces their surface motility: evidence from individual-based model simulations

    DEFF Research Database (Denmark)

    Mabrouk, Nabil; Deffuant, Guillaume; Tolker-Nielsen, Tim

    2010-01-01

    Recent experimental observations of Pseudomonas aeruginosa, a model bacterium in biofilm research, reveal that, under specific growth conditions, bacterial cells form patterns of interconnected microcolonies. In the present work, we use an individual-based model to assess the involvement...... of bacteria motility and self-produced extracellular substance in the formation of these patterns. In our simulations, the pattern of interconnected microcolonies appears only when bacteria motility is reduced by excreted extracellular macromolecules. Immotile bacteria form isolated microcolonies...... and constantly motile bacteria form flat biofilms. Based on experimental data and computer simulations, we suggest a mechanism that could be responsible for these interconnected microcolonies....

  3. Optimization of Land Use Pattern Reduces Surface Runoff and Sediment Loss in a Hilly-Gully Watershed at the Loess Plateau, China

    Directory of Open Access Journals (Sweden)

    Han Yini

    2016-04-01

    Full Text Available Aim of study: The aim is to find a way increasing gain yield and lessen area of farmland, and then increasing vegetation cover, improving environment and alleviating soil erosion.Area of study: The Hilly-Gully region at the loess plateau of China.Material and methods: In this study, an adjusted and optimized land use pattern was developed in Luoyugou watershed in the Yellow River valley based on the gradient distribution of land use types, and its effect on water and sediment transport was simulated using the SWAT model and GIS, with remote sensing images, land use maps and hydrologic data.Main results: The results indicate: average simulated runoff and sediment for the period 1986-2000 under conditions of the three land use pattern (2011, 2008 and optimized land use reduced by 0.002-0.013 m3/s (2.7-17.6% and 0.66 million tons, respectively. The runoff and sediment data obtained were compared with observed data from 2008, which showed that runoff and sediment production would be reduced by 467625 m3 and 22754 tons, respectively.Research highlights: The adjustment of the land use pattern in comprehensive consideration of vegetation and geography have a positive effect on water and sediment transport which will be important for decision making and water resources management, and provides a reference for future environmental management and ecological construction in the loess plateau Hilly-Gully region. 

  4. Brown Recluse spider bite mediated hemolysis: clinical features, a possible role for complement inhibitor therapy, and reduced RBC surface glycophorin A as a potential biomarker of venom exposure.

    Directory of Open Access Journals (Sweden)

    Eric A Gehrie

    Full Text Available BACKGROUND: The venom of Loxosceles reclusa (Brown Recluse spider can cause a severe, life-threatening hemolysis in humans for which no therapy is currently available in the USA beyond supportive measures. Because this hemolysis is uncommon, relatively little is known about its clinical manifestation, diagnosis, or management. Here, we aimed to clarify the clinical details of envenomation, to determine the efficacy of the complement inhibitor eculizumab to prevent the hemolysis in vitro, and to investigate markers of exposure to Brown Recluse venom. STUDY DESIGN AND METHODS: We performed a 10-year chart review of cases of Brown Recluse spider bite-mediated hemolysis at our institution. We also designed an in vitro assay to test the efficacy of eculizumab to inhibit hemolysis of venom exposed red blood cells. Finally, we compared levels of CD55, CD59 and glycophorin A on venom exposed versus venom-naïve cells. RESULTS: Most victims of severe Brown Recluse spider mediated hemolysis at our institution are children and follow an unpredictable clinical course. Brown Recluse spider bite mediated hemolysis is reduced by 79.2% (SD=18.8% by eculizumab in vitro. Erythrocyte glycophorin A, but not CD55 or CD59, is reduced after red blood cells are incubated with venom in vitro. CONCLUSION: Taken together, our laboratory data and clinical observations indicate that L. reclusa venom exposure results in non-specific antibody and complement fixation on red blood cells, resulting in complement mediated hemolysis that is curtailed by the complement inhibitor eculizumab in vitro. Glycophorin A measurement by flow cytometry may help to identify victims of L. reclusa envenomation.

  5. Brown Recluse spider bite mediated hemolysis: clinical features, a possible role for complement inhibitor therapy, and reduced RBC surface glycophorin A as a potential biomarker of venom exposure.

    Science.gov (United States)

    Gehrie, Eric A; Nian, Hui; Young, Pampee P

    2013-01-01

    The venom of Loxosceles reclusa (Brown Recluse spider) can cause a severe, life-threatening hemolysis in humans for which no therapy is currently available in the USA beyond supportive measures. Because this hemolysis is uncommon, relatively little is known about its clinical manifestation, diagnosis, or management. Here, we aimed to clarify the clinical details of envenomation, to determine the efficacy of the complement inhibitor eculizumab to prevent the hemolysis in vitro, and to investigate markers of exposure to Brown Recluse venom. We performed a 10-year chart review of cases of Brown Recluse spider bite-mediated hemolysis at our institution. We also designed an in vitro assay to test the efficacy of eculizumab to inhibit hemolysis of venom exposed red blood cells. Finally, we compared levels of CD55, CD59 and glycophorin A on venom exposed versus venom-naïve cells. Most victims of severe Brown Recluse spider mediated hemolysis at our institution are children and follow an unpredictable clinical course. Brown Recluse spider bite mediated hemolysis is reduced by 79.2% (SD=18.8%) by eculizumab in vitro. Erythrocyte glycophorin A, but not CD55 or CD59, is reduced after red blood cells are incubated with venom in vitro. Taken together, our laboratory data and clinical observations indicate that L. reclusa venom exposure results in non-specific antibody and complement fixation on red blood cells, resulting in complement mediated hemolysis that is curtailed by the complement inhibitor eculizumab in vitro. Glycophorin A measurement by flow cytometry may help to identify victims of L. reclusa envenomation.

  6. Inversion and Geological Significance of Minerals in Dark Matter of Craters of Oceanus Procellarum of Lunar Surface%月球风暴洋火山口暗物质矿物反演及地质意义

    Institute of Scientific and Technical Information of China (English)

    黄爽; 陈圣波; 查逢丽; 周超; 黄唯实

    2015-01-01

    月表主要矿物的空间分布是研究月球起源及演化等科学问题的重要信息之一。以风暴洋地区为例,根据不同矿物光谱在可见光-近红外波段的吸收特征,使用印度 M3(moon mineralogy mapper)数据,应用波谱特征拟合法(SFF)反演了火山口附近暗物质区域的单斜辉石、斜方辉石、橄榄石和尖晶石等铁镁质矿物的分布,反演结果显示:风暴洋地区提取的铁镁质矿物分布较集中,其中辉石含量较多,橄榄石和尖晶石含量相对较少。另外着重分析了橄榄石、尖晶石与周围矿物的关系及其地质意义。将提取结果与 Lucey 用于 Clementine 影像的光学模型填图结果进行对比显示,提取的橄榄石分布集中,但不存在大尺度的分布,这与本文的研究区域面积有关;就位置而言,二者具有较好的一致性。%There are a variety of geological structures in the Oceanus Procellarum,including 43 craters,some famous lunar mares like Mare Imbrium and Mare Frigoris,and so on.Since the Oceanus Procellarum is the candidate landing area of lunar exploration for some countries,it is important to carry out the inversion of the minerals in the dark matter of craters of the area to facilitate research,exploration and utilization of lunar resources in the future.In addition,distribution of minerals on lunar surface is important since it concerns the origin and evolution of the moon.In this paper,the Oceanus Procellarum is taken as study area,the minerals in the dark matter of crater are inversed according to the spectra absorption characteristics in the visi-ble and near-infrared bands of different minerals like clinopyroxene,orthopyroxene,olivine and spinel from M3 (moon mineral-ogy mapper)data by spectral feature fitting.The mafic minerals extracted from the Oceanus Procellarum are relatively concen-trated.The content of pyroxene is more than spinel and olivine.And the geological significance and

  7. The identification of suitable areas for afforestation in order to reduce the potential for surface runoff in the upper and middle sectors of Buzãu catchment

    Directory of Open Access Journals (Sweden)

    ROMULUS COSTACHE

    2015-07-01

    Full Text Available Deforestations, besides the global climate change, are the main cause of the intensification of f loods and flash - floods in the latest years. Since surface runoff is the main phenomenon leading to floods or flash - floods, afforestation is necessary, forest coverage being the element that retains most of the water from precipitation. The study area, repr esented by the upper and middle sectors of Buzau River basin, is one of the most affected regions of Romania by torrential phenomena. Also, the study area was chosen due to its considerable deforestation. This paper proposes a methodology created exclusive ly by GIS techniques in order to identify the areas suitable for afforestation. Thus, land cover and slope relief were taken into account when running the GIS model. Database processing and obtaining the final results were possible by implementing a workfl ow in Model Builder from ArcGIS 10.3, which can be later used as a tool for other study areas. The results of the study highlight Balaneasa, Bâsca Chiojdului and Sărăţel river basins, which record the highest shares of areas suitable for afforestation.

  8. Adsorption calorimetry during metal vapor deposition on single crystal surfaces: Increased flux, reduced optical radiation, and real-time flux and reflectivity measurements

    Science.gov (United States)

    Sellers, Jason R. V.; James, Trevor E.; Hemmingson, Stephanie L.; Farmer, Jason A.; Campbell, Charles T.

    2013-12-01

    Thin films of metals and other materials are often grown by physical vapor deposition. To understand such processes, it is desirable to measure the adsorption energy of the deposited species as the film grows, especially when grown on single crystal substrates where the structure of the adsorbed species, evolving interface, and thin film are more homogeneous and well-defined in structure. Our group previously described in this journal an adsorption calorimeter capable of such measurements on single-crystal surfaces under the clean conditions of ultrahigh vacuum [J. T. Stuckless, N. A. Frei, and C. T. Campbell, Rev. Sci. Instrum. 69, 2427 (1998)]. Here we describe several improvements to that original design that allow for heat measurements with ˜18-fold smaller standard deviation, greater absolute accuracy in energy calibration, and, most importantly, measurements of the adsorption of lower vapor-pressure materials which would have previously been impossible. These improvements are accomplished by: (1) using an electron beam evaporator instead of a Knudsen cell to generate the metal vapor at the source of the pulsed atomic beam, (2) changing the atomic beam design to decrease the relative amount of optical radiation that accompanies evaporation, (3) adding an off-axis quartz crystal microbalance for real-time measurement of the flux of the atomic beam during calorimetry experiments, and (4) adding capabilities for in situ relative diffuse optical reflectivity determinations (necessary for heat signal calibration). These improvements are not limited to adsorption calorimetry during metal deposition, but also could be applied to better study film growth of other elements and even molecular adsorbates.

  9. Escherichia coli growth under modeled reduced gravity

    Science.gov (United States)

    Baker, Paul W.; Meyer, Michelle L.; Leff, Laura G.

    2004-01-01

    Bacteria exhibit varying responses to modeled reduced gravity that can be simulated by clino-rotation. When Escherichia coli was subjected to different rotation speeds during clino-rotation, significant differences between modeled reduced gravity and normal gravity controls were observed only at higher speeds (30-50 rpm). There was no apparent affect of removing samples on the results obtained. When E. coli was grown in minimal medium (at 40 rpm), cell size was not affected by modeled reduced gravity and there were few differences in cell numbers. However, in higher nutrient conditions (i.e., dilute nutrient broth), total cell numbers were higher and cells were smaller under reduced gravity compared to normal gravity controls. Overall, the responses to modeled reduced gravity varied with nutrient conditions; larger surface to volume ratios may help compensate for the zone of nutrient depletion around the cells under modeled reduced gravity.

  10. Significant NRC Enforcement Actions

    Data.gov (United States)

    Nuclear Regulatory Commission — This dataset provides a list of Nuclear Regulartory Commission (NRC) issued significant enforcement actions. These actions, referred to as "escalated", are issued by...

  11. Choosing Outcomes of Significance.

    Science.gov (United States)

    Spady, William G.

    1994-01-01

    Outcomes are high-quality, culminating demonstrations of significant learning in context. The High Success Network uses the "Demonstration Mountain" to differentiate among three major "learning zones" and six different forms of learning demonstrations that increase in complexity, generalizability, and significance, along with…

  12. Dropwise Condensation of Low Surface Tension Fluids on Omniphobic Surfaces

    Science.gov (United States)

    Rykaczewski, Konrad; Paxson, Adam T.; Staymates, Matthew; Walker, Marlon L.; Sun, Xiaoda; Anand, Sushant; Srinivasan, Siddarth; McKinley, Gareth H.; Chinn, Jeff; Scott, John Henry J.; Varanasi, Kripa K.

    2014-03-01

    Compared to the significant body of work devoted to surface engineering for promoting dropwise condensation heat transfer of steam, much less attention has been dedicated to fluids with lower interfacial tension. A vast array of low-surface tension fluids such as hydrocarbons, cryogens, and fluorinated refrigerants are used in a number of industrial applications, and the development of passive means for increasing their condensation heat transfer coefficients has potential for significant efficiency enhancements. Here we investigate condensation behavior of a variety of liquids with surface tensions in the range of 12 to 28 mN/m on three types of omniphobic surfaces: smooth oleophobic, re-entrant superomniphobic, and lubricant-impregnated surfaces. We demonstrate that although smooth oleophobic and lubricant-impregnated surfaces can promote dropwise condensation of the majority of these fluids, re-entrant omniphobic surfaces became flooded and reverted to filmwise condensation. We also demonstrate that on the lubricant-impregnated surfaces, the choice of lubricant and underlying surface texture play a crucial role in stabilizing the lubricant and reducing pinning of the condensate. With properly engineered surfaces to promote dropwise condensation of low-surface tension fluids, we demonstrate a four to eight-fold improvement in the heat transfer coefficient.

  13. Spinodal Theory: A Common Rupturing Mechanism in Spinodal Dewetting and Surface Directed Phase Separation (Some Technological Aspects: Spatial Correlations and the Significance of Dipole-Quadrupole Interaction in Spinodal Dewetting

    Directory of Open Access Journals (Sweden)

    Satya Pal Singh

    2011-01-01

    Full Text Available The emerging structures in spinodal dewetting of thin nano films and spinodal decomposition of binary mixtures are found to be similar with certain differences attributed to the nonlinearities inherent in the wetting forces. This paper deals with the technological aspects of the spinodal processes by giving a brief account of the theory and to correlate the two phenomena termed as spinodal dewetting of thin nanofilms and surface-directed phase separation. The MC simulation micrographs at early stage of spinodal dewetting of a (linear polymer film confined between two hard walls (using FENE potential between the beads on same chain and Morse potential between inter and intra chain beads show similarities with surface-directed phase separation (using metropolis algorithm in creation of holes. The spinodal dewetting is also criticized on the basis of global minimization of free energy emerging from dipole-quadrupole interactions. A novel molecular scale-driving mechanism coming from asymmetric interface formation in spinodal processes is also proposed. It c