Sample records for saline pbs solution

  1. Influence of albumin on the electrochemical behaviour of Zr in phosphate buffered saline solutions.

    PubMed

    Wang, Lu-Ning; Huang, Xian-Qiu; Shinbine, Alyssa; Luo, Jing-Li

    2013-02-01

    The corrosion behaviour of Zr in phosphate buffered saline (PBS) solutions with various concentrations (0-4 g L(-1)) of albumin was studied by electrochemical techniques and surface analysis. Addition of albumin to PBS solutions moved the open circuit potential (OCP) to less nobler direction. OCP, polarization resistance and impedance increased and the corrosion current decreased over immersion duration. At early stages of immersion, the resistance was increased with the concentration of albumin because of the high adsorption kinetics of albumin on metal. After the long term immersion, the resistance in PBS without albumin was higher than PBS with albumin owing to the anodic dissolution effect of albumin on metal. According to the analysis of effective capacitances, a normal distribution of time-constants was proposed to estimate the surface film on Zr. A corrosion mechanism of Zr in PBS with different albumin was proposed based on electrochemical analysis.

  2. All-solution-processed PbS quantum dot solar modules

    NASA Astrophysics Data System (ADS)

    Jang, Jihoon; Shim, Hyung Cheoul; Ju, Yeonkyeong; Song, Jung Hoon; An, Hyejin; Yu, Jong-Su; Kwak, Sun-Woo; Lee, Taik-Min; Kim, Inyoung; Jeong, Sohee

    2015-05-01

    A rapid increase in power conversion efficiencies in colloidal quantum dot (QD) solar cells has been achieved recently with lead sulphide (PbS) QDs by adapting a heterojunction architecture, which consists of small-area devices associated with a vacuum-deposited buffer layer with metal electrodes. The preparation of QD solar modules by low-cost solution processes is required to further increase the power-to-cost ratio. Herein we demonstrate all-solution-processed flexible PbS QD solar modules with a layer-by-layer architecture comprising polyethylene terephthalate (PET) substrate/indium tin oxide (ITO)/titanium oxide (TiO2)/PbS QD/poly(3-hexylthiophene) (P3HT)/poly(3,4-ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT : PSS)/Ag, with an active area of up to 30 cm2, exhibiting a power conversion efficiency (PCE) of 1.3% under AM 1.5 conditions (PCE of 2.2% for a 1 cm2 unit cell). Our approach affords trade-offs between power and the active area of the photovoltaic devices, which results in a low-cost power source, and which is scalable to larger areas.A rapid increase in power conversion efficiencies in colloidal quantum dot (QD) solar cells has been achieved recently with lead sulphide (PbS) QDs by adapting a heterojunction architecture, which consists of small-area devices associated with a vacuum-deposited buffer layer with metal electrodes. The preparation of QD solar modules by low-cost solution processes is required to further increase the power-to-cost ratio. Herein we demonstrate all-solution-processed flexible PbS QD solar modules with a layer-by-layer architecture comprising polyethylene terephthalate (PET) substrate/indium tin oxide (ITO)/titanium oxide (TiO2)/PbS QD/poly(3-hexylthiophene) (P3HT)/poly(3,4-ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT : PSS)/Ag, with an active area of up to 30 cm2, exhibiting a power conversion efficiency (PCE) of 1.3% under AM 1.5 conditions (PCE of 2.2% for a 1 cm2 unit cell). Our approach affords trade

  3. All-solution-processed PbS quantum dot solar modules.

    PubMed

    Jang, Jihoon; Shim, Hyung Cheoul; Ju, Yeonkyeong; Song, Jung Hoon; An, Hyejin; Yu, Jong-Su; Kwak, Sun-Woo; Lee, Taik-Min; Kim, Inyoung; Jeong, Sohee

    2015-05-21

    A rapid increase in power conversion efficiencies in colloidal quantum dot (QD) solar cells has been achieved recently with lead sulphide (PbS) QDs by adapting a heterojunction architecture, which consists of small-area devices associated with a vacuum-deposited buffer layer with metal electrodes. The preparation of QD solar modules by low-cost solution processes is required to further increase the power-to-cost ratio. Herein we demonstrate all-solution-processed flexible PbS QD solar modules with a layer-by-layer architecture comprising polyethylene terephthalate (PET) substrate/indium tin oxide (ITO)/titanium oxide (TiO2)/PbS QD/poly(3-hexylthiophene) (P3HT)/poly(3,4-ethylenedioxythiophene) : poly(styrene sulfonate) (PEDOT : PSS)/Ag, with an active area of up to 30 cm(2), exhibiting a power conversion efficiency (PCE) of 1.3% under AM 1.5 conditions (PCE of 2.2% for a 1 cm(2) unit cell). Our approach affords trade-offs between power and the active area of the photovoltaic devices, which results in a low-cost power source, and which is scalable to larger areas.

  4. Cold physical plasma treated buffered saline solution as effective agent against pancreatic cancer cells.

    PubMed

    Bekeschus, Sander; Kading, Andre; Schroder, Tim; Wende, Kristian; Hackbarth, Christine; Liedtke, Kim Rouven; van der Linde, Julia; von Woedtke, Thomas; Heidecke, Claus-Dieter; Partecke, Lars-Ivo

    2018-05-07

    Cold physical plasma has been suggested as a new anticancer tool recently. However, direct use of plasma is limited to visible tumors and in some clinical situations not feasible. This includes repetitive treatment of peritoneal metastases which commonly occur in advanced gastrointestinal cancer and in pancreatic cancer in particular. In case of diffuse intraperitoneal metastatic spread Hyperthermic Intraperitoneal Intraoperative Chemotherapy (HIPEC) is used as therapeutic approach. Plasma treated solutions may combine their suspected systemic non-toxic characteristics with the anticancer effects of HIPEC. Previous work has provided evidence for an anti-cancer efficacy of plasma treated cell culture medium but the clinical relevance of such an approach is low due to its complex formulation and lack of medical accreditation. Therefore, plasma treated phosphate-buffered saline (PBS) which closely resembles medically certified solutions was investigated for its cytotoxic effect on 2D monolayer murine pancreatic cancer cells in vitro. It significantly decreased cancer cell metabolisms and proliferation whereas plasma treated Dulbecco's Modified Eagle Medium had no effect. Moreover, tumor cell growth attenuation was significantly higher when compared to syngeneic primary murine fibroblasts. Both results were confirmed in a human pancreatic cancer cell line. Finally, plasma treated PBS also decreased tumor sizes of pancreatic tumors in the TUM-CAM model in a three-dimensional manner, and induction of apoptosis was found to be responsible for all anticancer effects identified. Altogether, plasma treated PBS inhibited cell growth in 2D and 3D models of cancer. These results may help facilitating the development of new plasma derived anticancer agent with clinical relevance in the future. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  5. Spontaneous interfacial reaction between metallic copper and PBS to form cupric phosphate nanoflower and its enzyme hybrid with enhanced activity.

    PubMed

    He, Guangli; Hu, Weihua; Li, Chang Ming

    2015-11-01

    We herein report the spontaneous interfacial reaction between copper foil with 0.01 M phosphate buffered saline (PBS) to form free-standing cupric phosphate (Cu3(PO4)2) nanoflowers at ambient temperature. The underlying chemistry was thoroughly investigated and it is found that the formation of nanoflower is synergistically caused by dissolved oxygen, chlorine ions and phosphate ions. Enzyme-Cu3(PO4)2 hybrid nanoflower was further prepared successfully by using an enzyme-dissolving PBS solution and the enzymes in the hybrid exhibit enhanced biological activity. This work provides a facile route for large-scale synthesis of hierarchical inorganic and functional protein-inorganic hybrid architectures via a simple one-step solution-immersion reaction without using either template or surfactant, thus offering great potential for biosensing application among others. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Electrocapillary Phenomena at Edible Oil/Saline Interfaces.

    PubMed

    Nishimura, Satoshi; Ohzono, Takuya; Shoji, Kohei; Yagihara, Shin; Hayashi, Masafumi; Tanaka, Hisao

    2017-03-01

    Interfacial tension between edible oil and saline was measured under applied electric fields to understand the electrocapillary phenomena at the edible oil/saline interfaces. The electric responses of saline droplets in edible oil were also observed microscopically to examine the relationship between the electrocapillary phenomena and interfacial polarization. When sodium oleate (SO) was added to edible oil (SO-oil), the interfacial tension between SO-oil and saline decreased. However, no decrease was observed for additive-free oil or oleic acid (OA)-added oil (OA-oil). Microscopic observations suggested that the magnitude of interfacial polarization increased in the order of additive-free oil < OA-oil < SO-oil. The difference in electrocapillary phenomena between OA- and SO-oils was closely related to the polarization magnitude. In the case of SO-oil, the decrease in interfacial tension was remarkably larger for saline (pH 5.4~5.6) than that for phosphate-buffered saline (PBS, pH 7.2~7.4). However, no difference was observed between the electric responses of PBS and saline droplets in SO-oil. The difference in electrocapillary phenomena for PBS and saline could not be simply explained in terms of polarization magnitude. The ratio of ionized and non-ionized OA at the interfaces changed with the saline pH, possibly leading to the above difference.

  7. Solution-processed nanocrystalline PbS on paper substrate with pencil traced electrodes as visible photodetector

    NASA Astrophysics Data System (ADS)

    Vankhade, Dhaval; Chaudhuri, Tapas K.

    2018-04-01

    Paper-based PbS photodetector sensitive in the visible spectrum is reported. Nanocrystalline PbS-on-paper devices are fabricated by a spin coating method on white paper (300 GSM) from a methanolic precursor solution. Photodetector cells of gap 0.2 cm and length 0.5 cm are prepared by drawing contacts by monolithic cretacolor 8B pencil. X-ray diffractometer confirmed the deposition of nanocrystalline PbS films with 14 nm crystallites. The SEM illustrated the uniform coating of nanocrystalline PbS thin films on cellulose fibres of papers having an average thickness of fibres are 10 µm. The linear J-V characteristics in dark and under illumination of light using graphite trace on nanocrystalline PbS-on-paper shows good ohmic contact. The resistivity of pencil trace is 30 Ω.cm. Spectral response measurements of photodetector reveal the excellent sensitivity from 400 to 700 nm with a peak at 550 nm. The best responsivity anddetectivity are 0.7 A/W and 1.4 × 1012 Jones respectively. These paper-based low-cost photodetectors devices have fast photoresponse and recovery without baseline deviation.

  8. A comparison of the biocompatibility of phosphate-buffered saline and dianeal 3.86% in the rat model of peritoneal dialysis.

    PubMed

    Wieczorowska-Tobis, K; Polubinska, A; Breborowicz, A; Oreopoulos, D G

    2001-01-01

    Phosphate-buffered saline (PBS), an isotonic solution with a physiologic pH can be considered an example of a biocompatible dialysis fluid. This study compared the biocompatibility of PBS with that of Dianeal 3.86% (Baxter Healthcare Corporation, Deerfield, IL, U.S.A.), using a model of peritoneal dialysis in the rat. In an acute experiment, after catheter implantation, rats were infused on day 1 with PBS, on day 5 with standard dialysis solution (Dianeal 3.86%), and on day 7 again with PBS. When rats were injected with Dianeal 3.86%, the inflammatory reaction was suppressed as compared with PBS. The cell count was lower with Dianeal (-85%, p < 0.001), the neutrophil:macrophage ratio in dialysate was 80% lower (p < 0.01), total protein concentration in the Dianeal dialysate was 73% lower (p < 0.01), and the dialysate nitrite level was 45% lower (p < 0.01). In a chronic experiment, after catheter implantation, rats were dialyzed for four weeks with PBS or with Dianeal 3.86%. At the end of the study, a 1-hour peritoneal equilibration test (PET) was performed. As evaluated on a semiquantitative scale, macroscopic changes in the peritoneum were more severe in rats exposed to PBS than in those exposed to Dianeal 3.86% (8.6 +/- 3.2 vs 5.2 +/- 2.6, p < 0.05). The thickness of the visceral peritoneum was comparable in both groups; but, in PBS-treated rats, the peritoneal interstitium contained more inflammatory cells and more new vessels. During the 1-hour PET, peritoneal permeability to water and solutes was comparable in the two groups. Despite a more physiologic composition, PBS is a less biocompatible peritoneal dialysis solutions than is standard, acidic, hypertonic dialysis solution.

  9. Comparison between Saline Solution Containing Heparin versus Saline Solution in the Lock of Totally Implantable Catheters.

    PubMed

    Brito, Antonio Rafael de Oliveira; Nishinari, Kenji; Saad, Paulo Fernandes; Saad, Karen Ruggeri; Pereira, Monica Aparecida Tomé; Emídio, Suellen Cristina Dias; Yazbek, Guilherme; Bomfim, Guilherme Andre Zottele; Cavalcante, Rafael Noronha; Krutman, Mariana; Teivelis, Marcelo Passos; Pignataro, Bruno Soriano; Fonseca, Igor Yoshio Imagawa; Centofanti, Guilherme; Soares, Bruno Leonardo Freitas

    2018-02-01

    There are only 3 studies comparing the efficacy of 2 different types of lock used in totally implantable catheters regarding occlusion or reflux dysfunction. The present study contains the largest published casuistry (862 patients) and is the only one that analyzes 3 parameters: occlusion, reflux dysfunction, and flow dysfunction. This was a retrospective study of patients operated at a large oncology center and followed up in the outpatient clinic between 2007 and 2015. The patients were divided into 2 groups according to the type of lock: the Hep group (heparine), whose lock was composed of saline solution 0.9% with heparin (100 IU/mL) and the SS group (saline solution), whose lock was composed of saline solution 0.9%. The Hep group was composed of 270 patients (31%) and the SS group of 592 patients (69%). Regarding occlusion, there were 8 cases in the Hep group (2.96%) and 8 in the SS group (1.35%; P = 0.11); in relation to reflux dysfunction, there were 8 cases in the Hep group (2.96%) and 8 in the SS group (1.35%; P = 0.11); in relation to flow dysfunction, there was 1 case in the Hep group (0.37%) and 4 cases in the SS group (0.68%; P = 1). There was no statistically significant difference between the groups regarding occlusion, reflux dysfunction, and flow dysfunction. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Variations in peak nasal inspiratory flow among healthy students after using saline solutions.

    PubMed

    Olbrich Neto, Jaime; Olbrich, Sandra Regina Leite Rosa; Mori, Natália Leite Rosa; Oliveira, Ana Elisa de; Corrente, José Eduardo

    2016-01-01

    Nasal hygiene with saline solutions has been shown to relieve congestion, reduce the thickening of the mucus and keep nasal cavity clean and moist. Evaluating whether saline solutions improve nasal inspiratory flow among healthy children. Students between 8 and 11 years of age underwent 6 procedures with saline solutions at different concentrations. The peak nasal inspiratory flow was measured before and 30 min after each procedure. Statistical analysis was performed by means of t test, analysis of variance, and Tukey's test, considering p<0.05. We evaluated 124 children at all stages. There were differences on the way a same concentration was used. There was no difference between 0.9% saline solution and 3% saline solution by using a syringe. The 3% saline solution had higher averages of peak nasal inspiratory flow, but it was not significantly higher than the 0.9% saline solution. It is important to offer various options to patients. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  11. Corrosion behavior of pristine and added MgB2 in Phosphate Buffered Saline Solution

    NASA Astrophysics Data System (ADS)

    Batalu, D.; Bojin, D.; Ghiban, B.; Aldica, G.; Badica, P.

    2012-09-01

    We have obtained by Spark Plasma Sintering (SPS), dense samples of MgB2 added with Ho2O3. Starting composition was (MgB2)0.975(HoO1.5)0.025 and we used addition powders with an average particle size below and above 100 nm. For Mg, pristine and added MgB2 samples we measured potentiodynamic polarization curves in Phosphate Buffered Saline (PBS) solution media at room temperature. MgB2 based composites show corrosion/ degradation effects. This behavior is in principle similar to Mg based alloys in the same media. Our work suggests that the different morphologies and phase compositions of the SPS-ed samples influence the interaction with corrosion medium; hence additions can play an important role in controlling the corrosion rate. Pristine MgB2 show a significant improvement of the corrosion resistance, if compared with Mg. The best corrosion resistance is obtained for pristine MgB2, followed by MgB2 with nano-Ho2O3 and μ-Ho2O3 additions.

  12. Reinforcement effect of poly(butylene succinate) (PBS)-grafted cellulose nanocrystal on toughened PBS/polylactic acid blends.

    PubMed

    Zhang, Xuzhen; Zhang, Yong

    2016-04-20

    Poly(butylene succinate) (PBS)/polylactic acid (PLA) blends modified with dicumyl peroxide (DCP) were reinforced by PBS-g-cellulose nanocrystal (CNC) through melt mixing. PBS-g-CNC was prepared through in situ polymerization and its structure was confirmed by FTIR, (13)C NMR, XPS and GPC analysis after saponification. The morphological analysis of PBS/PLA/PBS-g-CNC composites before and after etched by CH2Cl2 shows that the addition of DCP and PBS-g-CNC could decrease the size of PBS as a dispersed phase in PLA matrix and improve the dispersion of PBS-g-CNC in both PBS and PLA phases, which could affect the crystallization and mechanical properties of composites. The crystallinity of PLA α'-phase crystal in PBS/PLA/PBS-g-CNC composites is increased obviously by the addition of PBS-g-CNC, leading to an increase of the crystallinity of the composites. PBS/PLA blends modified by DCP have high Notched Izod impact strength and moduli, and the values are increased by the addition of PBS-g-CNC. Both storage modulus and glass translation temperature of PBS/PLA blend are increased by DCP and PBS-g-CNC, which is proved by DMA results, showing a weak molecular segment mobility of PBS/PLA matrix. The addition of DCP decreases the crystallization temperature and crystallinity of PBS/PLA composite, but increases the thermal stability of composites, mostly because of the crosslink effect of DCP on PBS/PLA matrix. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Agglomeration of Luminescent Porous Silicon Nanoparticles in Colloidal Solutions

    NASA Astrophysics Data System (ADS)

    Herynková, Kateřina; Šlechta, Miroslav; Šimáková, Petra; Fučíková, Anna; Cibulka, Ondřej

    2016-08-01

    We have prepared colloidal solutions of clusters composed from porous silicon nanoparticles in methanol, water and phosphate-buffered saline (PBS). Even if the size of the nanoclusters is between 60 and 500 nm, due to their highly porous "cauliflower"-like structure, the porous silicon nanoparticles are composed of interconnected nanocrystals having around 2.5 nm in size and showing strong visible luminescence in the orange-red spectral region (centred at 600-700 nm). Hydrophilic behaviour and good solubility of the nanoclusters in water and water-based solutions were obtained by adding hydrogen peroxide into the etching solution during preparation and 16 min long after-bath in hydrogen peroxide. By simple filtration of the solutions with syringe filters, we have extracted smaller nanoclusters with sizes of approx. 60-70 nm; however, these nanoclusters in water and PBS solution (pH neutral) are prone to agglomeration, as was confirmed by zeta potential measurements. When the samples were left at ambient conditions for several weeks, the typical nanocluster size increased to approx. 330-400 nm and then remained stable. However, both freshly filtered and aged samples (with agglomerated porous silicon nanoparticles) of porous silicon in water and PBS solutions can be further used for biological studies or as luminescent markers in living cells.

  14. Study of structural and optical properties of PbS thin films

    NASA Astrophysics Data System (ADS)

    Homraruen, T.; Sudswasd, Y.; Sorod, R.; Kayunkid, N.; Yindeesuk, W.

    2018-03-01

    This research aimed to synthesize lead sulfide (PbS) thin films on glass slides using the successive ion layer absorption and reaction (SILAR) method. We studied the optical properties and structure of PbS thin films by changing the number of dipping cycles and the concentration of precursor solution. The results of this experiment show that different conditions have a considerable influence on the thickness and absorbance of the films. When the number of dipping cycles and the concentration of the solution are increased, film thickness and absorbance tend to become higher. The xrays diffraction pattern showed all the diffraction peaks which confirmed the face center cubic and the structure of PbS had identified. Grain size computation was used to confirm how much these conditions could be affected.

  15. Eolian transport, saline lake basins, and groundwater solutes

    USGS Publications Warehouse

    Wood, Warren W.; Sanford, Ward E.

    1995-01-01

    Eolian processes associated with saline lakes are shown to be important in determining solute concentration in groundwater in arid and semiarid areas. Steady state mass balance analyses of chloride in the groundwater at Double Lakes, a saline lake basin in the southern High Plains of Texas, United States, suggest that approximately 4.5 × 105 kg of chloride is removed from the relatively small (4.7 km2) basin floor each year by deflation. This mass enters the groundwater down the wind gradient from the lake, degrading the water quality. The estimates of mass transport were independently determined by evaluation of solutes in the unsaturated zone and by solute mass balance calculations of groundwater flux. Transport of salts from the lake was confirmed over a short term (2 years) by strategically placed dust collectors. Results consistent with those at Double Lake were obtained from dune surfaces collected upwind and downwind from a sabkha near the city of Abu Dhabi in the United Arab Emirates. The eolian transport process provides an explanation of the degraded groundwater quality associated with the 30–40 saline lake basins on the southern half of the southern High Plains of Texas and New Mexico and in many other arid and semiarid areas.

  16. Graphene and PbS quantum dot hybrid vertical phototransistor

    NASA Astrophysics Data System (ADS)

    Song, Xiaoxian; Zhang, Yating; Zhang, Haiting; Yu, Yu; Cao, Mingxuan; Che, Yongli; Dai, Haitao; Yang, Junbo; Ding, Xin; Yao, Jianquan

    2017-04-01

    A field-effect phototransistor based on a graphene and lead sulfide quantum dot (PbS QD) hybrid in which PbS QDs are embedded in a graphene matrix has been fabricated with a vertical architecture through a solution process. The n-type Si/SiO2 substrate (gate), Au/Ag nanowire transparent source electrode, active layer and Au drain electrode are vertically stacked in the device, which has a downscaled channel length of 250 nm. Photoinduced electrons in the PbS QDs leap into the conduction band and fill in the trap states, while the photoinduced holes left in the valence band transfer to the graphene and form the photocurrent under biases from which the photoconductive gain is evaluated. The graphene/QD-based vertical phototransistor shows a photoresponsivity of 2 × 103 A W-1, and specific detectivity up to 7 × 1012 Jones under 808 nm laser illumination with a light irradiance of 12 mW cm-2. The solution-processed vertical phototransistor provides a new facile method for optoelectronic device applications.

  17. Coefficient of Friction of Human Corneal Tissue.

    PubMed

    Wilson, Tawnya; Aeschlimann, Rudolf; Tosatti, Samuele; Toubouti, Youssef; Kakkassery, Joseph; Osborn Lorenz, Katherine

    2015-09-01

    A novel property evaluation methodology was used to determine the elusive value for the human corneal coefficient of friction (CoF). Using a microtribometer on 28 fresh human donor corneas with intact epithelia, the CoF was determined in 4 test solutions (≥5 corneas/solution): tear-mimicking solution (TMS) in borate-buffered saline (TMS-PS), TMS in phosphate-buffered saline (TMS-PBS), TMS with HEPES-buffered saline (TMS-HEPES), and tear-like fluid in PBS (TLF-PBS). Mean (SD) CoF values ranged from 0.006 to 0.015 and were 0.013 (0.010) in TMS-PS, 0.006 (0.003) in TMS-PBS, 0.014 (0.005) in TMS-HEPES, and 0.015 (0.009) in TLF-PBS. Statistically significant differences were shown for TMS-PBS versus TLF (P = 0.0424) and TMS-PBS versus TMS-HEPES (P = 0.0179), but not for TMS-PBS versus TMS-PS (P = 0.2389). Successful measurement of the fresh human corneal tissue CoF was demonstrated, with values differing in the evaluated buffer solutions, within this limited sample size.

  18. Agglomeration of Luminescent Porous Silicon Nanoparticles in Colloidal Solutions.

    PubMed

    Herynková, Kateřina; Šlechta, Miroslav; Šimáková, Petra; Fučíková, Anna; Cibulka, Ondřej

    2016-12-01

    We have prepared colloidal solutions of clusters composed from porous silicon nanoparticles in methanol, water and phosphate-buffered saline (PBS). Even if the size of the nanoclusters is between 60 and 500 nm, due to their highly porous "cauliflower"-like structure, the porous silicon nanoparticles are composed of interconnected nanocrystals having around 2.5 nm in size and showing strong visible luminescence in the orange-red spectral region (centred at 600-700 nm). Hydrophilic behaviour and good solubility of the nanoclusters in water and water-based solutions were obtained by adding hydrogen peroxide into the etching solution during preparation and 16 min long after-bath in hydrogen peroxide. By simple filtration of the solutions with syringe filters, we have extracted smaller nanoclusters with sizes of approx. 60-70 nm; however, these nanoclusters in water and PBS solution (pH neutral) are prone to agglomeration, as was confirmed by zeta potential measurements. When the samples were left at ambient conditions for several weeks, the typical nanocluster size increased to approx. 330-400 nm and then remained stable. However, both freshly filtered and aged samples (with agglomerated porous silicon nanoparticles) of porous silicon in water and PBS solutions can be further used for biological studies or as luminescent markers in living cells.

  19. Colloid transport in porous media: impact of hyper-saline solutions.

    PubMed

    Magal, Einat; Weisbrod, Noam; Yechieli, Yoseph; Walker, Sharon L; Yakirevich, Alexander

    2011-05-01

    The transport of colloids suspended in natural saline solutions with a wide range of ionic strengths, up to that of Dead Sea brines (10(0.9) M) was explored. Migration of microspheres through saturated sand columns of different sizes was studied in laboratory experiments and simulated with mathematical models. Colloid transport was found to be related to the solution salinity as expected. The relative concentration of colloids at the columns outlet decreased (after 2-3 pore volumes) as the solution ionic strength increased until a critical value was reached (ionic strength > 10(-1.8) M) and then remained constant above this level of salinity. The colloids were found to be mobile even in the extremely saline brines of the Dead Sea. At such high ionic strength no energetic barrier to colloid attachment was presumed to exist and colloid deposition was expected to be a favorable process. However, even at these salinity levels, colloid attachment was not complete and the transport of ∼ 30% of the colloids through the 30-cm long columns was detected. To further explore the deposition of colloids on sand surfaces in Dead Sea brines, transport was studied using 7-cm long columns through which hundreds of pore volumes were introduced. The resulting breakthrough curves exhibited a bimodal shape whereby the relative concentration (C/C(0)) of colloids at the outlet rose to a value of 0.8, and it remained relatively constant (for the ∼ 18 pore volumes during which the colloid suspension was flushed through the column) and then the relative concentration increased to a value of one. The bimodal nature of the breakthrough suggests different rates of colloid attachment. Colloid transport processes were successfully modeled using the limited entrapment model, which assumes that the colloid attachment rate is dependent on the concentration of the attached colloids. Application of this model provided confirmation of the colloid aggregation and their accelerated attachment during

  20. Transient bleaching of small PbS colloids. Influence of surface properties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nenadovic, M.T.; Comor, M.I.; Vasic, V.

    1990-08-09

    Small PbS colloids with a particle diameter of 40 {angstrom} were prepared in aqueous solution, and their absorption spectra exhibit several maxima. Injection of electrons into these particles was achieved by using the pulse radiolysis technique. Excess electrons trapped on the surface lead to a blue shift in the absorption edge of colloids. The appearance of this shift depends critically on the method of colloid preparation. PbS and CdS colloids prepared at pH < 6 have long-lived bleaching, which disappears after several seconds. On the other hand, absorption bleaching does not appear after the addition of hydroxide ions to colloidalmore » solutions (pH > 8). The existence of a hydroxide ion on the particle surface most likely removes surface defects on which electrons are trapped. PbS colloids prepared in the presence of 3-mercapto-1,2-propanediol have an unstructured absorption spectrum, which is due to a wide particle size distribution (10-50 {angstrom}).« less

  1. Effect of synovial fluid, phosphate-buffered saline solution, and water on the dissolution and corrosion properties of CoCrMo alloys as used in orthopedic implants.

    PubMed

    Lewis, A C; Kilburn, M R; Papageorgiou, I; Allen, G C; Case, C P

    2005-06-15

    The corrosion and dissolution of high- and low-carbon CoCrMo alloys, as used in orthopedic joint replacements, were studied by immersing samples in phosphate-buffered saline (PBS), water, and synovial fluid at 37 degrees C for up to 35 days. Bulk properties were analyzed with a fine ion beam microscope. Surface analyses by X-ray photoelectron spectroscopy and Auger electron spectroscopy showed surprisingly that synovial fluid produced a thin oxide/hydroxide layer. Release of ions into solution from the alloy also followed an unexpected pattern where synovial fluid, of all the samples, had the highest Cr concentration but the lowest Co concentration. The presence of carbide inclusions in the alloy did not affect the corrosion or the dissolution mechanisms, although the carbides were a significant feature on the metal surface. Only one mechanism was recognized as controlling the thickness of the oxide/hydroxide interface. The analysis of the dissolved metal showed two mechanisms at work: (1) a protein film caused ligand-induced dissolution, increasing the Cr concentration in synovial fluid, and was explained by the equilibrium constants; (2) corrosion at the interface increased the Co in PBS. The effect of prepassivating the samples (ASTM F-86-01) did not always have the desired effect of reducing dissolution. The release of Cr into PBS increased after prepassivation. The metal-synovial fluid interface did not contain calcium phosphate as a deposit, typically found where samples are exposed to calcium rich bodily fluids. (c) 2005 Wiley Periodicals, Inc.

  2. Influence of D-Penicillamine on the Viscosity of Hyaluronic Acid Solutions

    NASA Astrophysics Data System (ADS)

    Liang, Jing; Krause, Wendy E.; Colby, Ralph H.

    2006-03-01

    Polyelectrolyte hyaluronic acid (HA, hyaluronan) is an important component in synovial fluid. Its presence results in highly viscoelastic solutions with excellent lubricating and shock-absorbing properties. In comparison to healthy synovial fluid, diseased fluid has a reduced viscosity. In osteoarthritis this reduction in viscosity results from a decline in both the molecular weight and concentration of hyaluronic acid HA. Initial results indicate that D-penicillamine affects the rheology of bovine synovial fluid, a model synovial fluid solution, and its components, including HA. In order to understand how D-penicillamine modifies the viscosity of these solutions, the rheological properties of sodium hyaluronate (NaHA) in phosphate-buffered saline (PBS) with D-penicillamine were studied as function of time, D-penicillamine concentration (0 -- 0.01 M), and storage conditions. Penicillamine has a complex, time dependent effect on the viscosity of NaHA solutions---reducing the zero shear rate viscosity of a 3 mg/mL NaHA in PBS by ca. 40% after 44 days.

  3. Discoloration of titanium alloy in acidic saline solutions with peroxide.

    PubMed

    Takemoto, Shinji; Hattori, Masayuki; Yoshinari, Masao; Kawada, Eiji; Oda, Yutaka

    2013-01-01

    The objective of this study was to compare corrosion behavior in several titanium alloys with immersion in acidulated saline solutions containing hydrogen peroxide. Seven types of titanium alloy were immersed in saline solutions with varying levels of pH and hydrogen peroxide content, and resulting differences in color and release of metallic elements determined in each alloy. Some alloys were characterized using Auger electron spectroscopy. Ti-55Ni alloy showed a high level of dissolution and difference in color. With immersion in solution containing hydrogen peroxide at pH 4, the other alloys showed a marked difference in color but a low level of dissolution. The formation of a thick oxide film was observed in commercially pure titanium showing discoloration. The results suggest that discoloration in titanium alloys immersed in hydrogen peroxide-containing acidulated solutions is caused by an increase in the thickness of this oxide film, whereas discoloration of Ti-55Ni is caused by corrosion.

  4. Analytical steady-state solutions for water-limited cropping systems using saline irrigation water

    NASA Astrophysics Data System (ADS)

    Skaggs, T. H.; Anderson, R. G.; Corwin, D. L.; Suarez, D. L.

    2014-12-01

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems modeling framework that accounts for reduced plant water uptake due to root zone salinity. Two explicit, closed-form analytical solutions for the root zone solute concentration profile are obtained, corresponding to two alternative functional forms of the uptake reduction function. The solutions express a general relationship between irrigation water salinity, irrigation rate, crop salt tolerance, crop transpiration, and (using standard approximations) crop yield. Example applications are illustrated, including the calculation of irrigation requirements for obtaining targeted submaximal yields, and the generation of crop-water production functions for varying irrigation waters, irrigation rates, and crops. Model predictions are shown to be mostly consistent with existing models and available experimental data. Yet the new solutions possess advantages over available alternatives, including: (i) the solutions were derived from a complete physical-mathematical description of the system, rather than based on an ad hoc formulation; (ii) the analytical solutions are explicit and can be evaluated without iterative techniques; (iii) the solutions permit consideration of two common functional forms of salinity induced reductions in crop water uptake, rather than being tied to one particular representation; and (iv) the utilized modeling framework is compatible with leading transient-state numerical models.

  5. Capacitive Deionization of High-Salinity Solutions

    DOE PAGES

    Sharma, Ketki; Gabitto, Jorge; Mayes, Richard T.; ...

    2014-12-22

    Desalination of high salinity solutions has been studied using a novel experimental technique and a theoretical model. Neutron imaging has been employed to visualize lithium ions in mesoporous carbon materials, which are used as electrodes in capacitive deionization for water desalination. Experiments were conducted with a flow-through capacitive deionization cell designed for neutron imaging and with lithium chloride ( 6LiCl) as the electrolyte. Sequences of neutron images have been obtained at a relatively high concentration of lithium chloride ( 6LiCl) solution to provide information on the transport of ions within the electrodes. A new model that computes the individual ionicmore » concentration profiles inside mesoporous carbon electrodes has been used to simulate the capacitive deionization process. Modifications have also been introduced into the simulation model to calculate results at high electrolyte concentrations. Experimental data and simulation results provide insight into why capacitive deionization is not effective for desalination of high ionic-strength solutions. The combination of experimental information, obtained through neutron imaging, with the theoretical model will help in the design of capacitive deionization devices, which can improve the process for high ionic-strength solutions.« less

  6. Common toads (Bufo arenarum) learn to anticipate and avoid hypertonic saline solutions.

    PubMed

    Daneri, M Florencia; Papini, Mauricio R; Muzio, Rubén N

    2007-11-01

    Toads (Bufo arenarum) were exposed to pairings between immersion in a neutral saline solution (i.e., one that caused no significant variation in fluid balance), followed by immersion in a highly hypertonic saline solution (i.e., one that caused water loss). In Experiment 1, solutions were presented in a Pavlovian conditioning arrangement. A group receiving a single neutral-highly hypertonic pairing per day exhibited a greater conditioned increase in heart rate than groups receiving either the same solutions in an explicitly unpaired fashion, or just the neutral solution. Paired toads also showed a greater ability to compensate for water loss across trials than that of the explicitly unpaired group. Using the same reinforcers and a similar apparatus, Experiment 2 demonstrated that toads learn a one-way avoidance response motivated by immersion in the highly hypertonic solution. Cardiac and avoidance conditioning are elements of an adaptive system for confronting aversive situations involving loss of water balance. Copyright 2007 APA.

  7. Tandem Solar Cells from Solution-Processed CdTe and PbS Quantum Dots Using a ZnTe-ZnO Tunnel Junction.

    PubMed

    Crisp, Ryan W; Pach, Gregory F; Kurley, J Matthew; France, Ryan M; Reese, Matthew O; Nanayakkara, Sanjini U; MacLeod, Bradley A; Talapin, Dmitri V; Beard, Matthew C; Luther, Joseph M

    2017-02-08

    We developed a monolithic CdTe-PbS tandem solar cell architecture in which both the CdTe and PbS absorber layers are solution-processed from nanocrystal inks. Due to their tunable nature, PbS quantum dots (QDs), with a controllable band gap between 0.4 and ∼1.6 eV, are a promising candidate for a bottom absorber layer in tandem photovoltaics. In the detailed balance limit, the ideal configuration of a CdTe (E g = 1.5 eV)-PbS tandem structure assumes infinite thickness of the absorber layers and requires the PbS band gap to be 0.75 eV to theoretically achieve a power conversion efficiency (PCE) of 45%. However, modeling shows that by allowing the thickness of the CdTe layer to vary, a tandem with efficiency over 40% is achievable using bottom cell band gaps ranging from 0.68 and 1.16 eV. In a first step toward developing this technology, we explore CdTe-PbS tandem devices by developing a ZnTe-ZnO tunnel junction, which appropriately combines the two subcells in series. We examine the basic characteristics of the solar cells as a function of layer thickness and bottom-cell band gap and demonstrate open-circuit voltages in excess of 1.1 V with matched short circuit current density of 10 mA/cm 2 in prototype devices.

  8. Tandem Solar Cells from Solution-Processed CdTe and PbS Quantum Dots Using a ZnTe–ZnO Tunnel Junction

    DOE PAGES

    Crisp, Ryan W.; Pach, Gregory F.; Kurley, J. Matthew; ...

    2017-01-10

    Here, we developed a monolithic CdTe-PbS tandem solar cell architecture in which both the CdTe and PbS absorber layers are solution-processed from nanocrystal inks. Due to their tunable nature, PbS quantum dots (QDs), with a controllable band gap between 0.4 and ~1.6 eV, are a promising candidate for a bottom absorber layer in tandem photovoltaics. In the detailed balance limit, the ideal configuration of a CdTe (E g = 1.5 eV)-PbS tandem structure assumes infinite thickness of the absorber layers and requires the PbS band gap to be 0.75 eV to theoretically achieve a power conversion efficiency (PCE) of 45%.more » But, modeling shows that by allowing the thickness of the CdTe layer to vary, a tandem with efficiency over 40% is achievable using bottom cell band gaps ranging from 0.68 and 1.16 eV. In a first step toward developing this technology, we explore CdTe-PbS tandem devices by developing a ZnTe-ZnO tunnel junction, which appropriately combines the two subcells in series. Furthermore, we examine the basic characteristics of the solar cells as a function of layer thickness and bottom-cell band gap and demonstrate open-circuit voltages in excess of 1.1 V with matched short circuit current density of 10 mA/cm 2 in prototype devices.« less

  9. Ultra high pressure homogenization (UHPH) inactivation of Bacillus amyloliquefaciens spores in phosphate buffered saline (PBS) and milk

    PubMed Central

    Dong, Peng; Georget, Erika S.; Aganovic, Kemal; Heinz, Volker; Mathys, Alexander

    2015-01-01

    Ultra high pressure homogenization (UHPH) opens up new areas for dynamic high pressure assisted thermal sterilization of liquids. Bacillus amyloliquefaciens spores are resistant to high isostatic pressure and temperature and were suggested as potential surrogate for high pressure thermal sterilization validation. B. amyloliquefaciens spores suspended in PBS buffer (0.01 M, pH 7.0), low fat milk (1.5%, pH 6.7), and whole milk (3.5%, pH 6.7) at initial concentration of ~106 CFU/mL were subjected to UHPH treatments at 200, 300, and 350 MPa with an inlet temperature at ~80°C. Thermal inactivation kinetics of B. amyloliquefaciens spores in PBS and milk were assessed with thin wall glass capillaries and modeled using first-order and Weibull models. The residence time during UHPH treatments was estimated to determine the contribution of temperature to spore inactivation by UHPH. No sublethal injury was detected after UHPH treatments using sodium chloride as selective component in the nutrient agar medium. The inactivation profiles of spores in PBS buffer and milk were compared and fat provided no clear protective effect for spores against treatments. Treatment at 200 MPa with valve temperatures lower than 125°C caused no reduction of spores. A reduction of 3.5 log10CFU/mL of B. amyloliquefaciens spores was achieved by treatment at 350 MPa with a valve temperature higher than 150°C. The modeled thermal inactivation and observed inactivation during UHPH treatments suggest that temperature could be the main lethal effect driving inactivation. PMID:26236296

  10. Metal release and speciation of released chromium from a biomedical CoCrMo alloy into simulated physiologically relevant solutions.

    PubMed

    Hedberg, Yolanda; Odnevall Wallinder, Inger

    2014-05-01

    The objective of this study was to investigate the extent of released Co, Cr(III), Cr(VI), and Mo from a biomedical high-carbon CoCrMo alloy exposed in phosphate-buffered saline (PBS), without and with the addition of 10 µM H2 O2 (PBS + H2 O2 ), and 10 g L(-1) bovine serum albumin (PBS + BSA) for time periods up to 28 days. Comparative studies were made on AISI 316L for the longest time period. No Cr(VI) release was observed for any of the alloys in either PBS or PBS + H2 O2 at open-circuit potential (no applied potential). However, at applied potentials (0.7 V vs. Ag/AgCl), Cr was primarily released as Cr(VI). Co was preferentially released from the CoCrMo alloy at no applied potential. As a consequence, Cr was enriched in the utmost surface oxide reducing the extent of metal release over time. This passivation effect was accelerated in PBS + H2 O2 . As previously reported for 316L, BSA may also enhance metal release from CoCrMo. However, this was not possible to verify due to the precipitation of metal-protein complexes with reduced metal concentrations in solution as a consequence. This was particularly important for Co-BSA complexes after sufficient time and resulted in an underestimation of metals in solution. Copyright © 2013 Wiley Periodicals, Inc.

  11. Enhancement of the photovoltaic performance in P3HT: PbS hybrid solar cells using small size PbS quantum dots

    NASA Astrophysics Data System (ADS)

    Firdaus, Yuliar; Vandenplas, Erwin; Justo, Yolanda; Gehlhaar, Robert; Cheyns, David; Hens, Zeger; Van der Auweraer, Mark

    2014-09-01

    Different approaches of surface modification of the quantum dots (QDs), namely, solution-phase (octylamine, octanethiol) and post-deposition (acetic acid, 1,4-benzenedithiol) ligand exchange were used in the fabrication of hybrid bulk heterojunction solar cell containing poly (3-hexylthiophene) (P3HT) and small (2.4 nm) PbS QDs. We show that replacing oleic acid by shorter chain ligands improves the figures of merit of the solar cells. This can possibly be attributed to a combination of a reduced thickness of the barrier for electron transfer and an optimized phase separation. The best results were obtained for post-deposition ligand exchange by 1,4-benzenedithiol, which improves the power conversion efficiency of solar cells based on a bulk heterojunction of lead sulfide (PbS) QDs and P3HT up to two orders of magnitude over previously reported hybrid cells based on a bulk heterojunction of P3HT:PbS QDs, where the QDs are capped by acetic acid ligands. The optimal performance was obtained for solar cells with 69 wt. % PbS QDs. Besides the ligand effects, the improvement was attributed to the formation of an energetically favorable bulk heterojunction with P3HT, when small size (2.4 nm) PbS QDs were used. Dark current density-voltage (J-V) measurements carried out on the device provided insight into the working mechanism: the comparison between the dark J-V characteristics of the bench mark system P3HT:PCBM and the P3HT:PbS blends allows us to conclude that a larger leakage current and a more efficient recombination are the major factors responsible for the larger losses in the hybrid system.

  12. Evaluating Battery-like Reactions to Harvest Energy from Salinity Differences using Ammonium Bicarbonate Salt Solutions.

    PubMed

    Kim, Taeyoung; Rahimi, Mohammad; Logan, Bruce E; Gorski, Christopher A

    2016-05-10

    Mixing entropy batteries (MEBs) are a new approach to generate electricity from salinity differences between two aqueous solutions. To date, MEBs have only been prepared from solutions containing chloride salts, owing to their relevance in natural salinity gradients created from seawater and freshwater. We hypothesized that MEBs could capture energy using ammonium bicarbonate (AmB), a thermolytic salt that can be used to convert waste heat into salinity gradients. We examined six battery electrode materials. Several of the electrodes were unstable in AmB solutions or failed to produce expected voltages. Of the electrode materials tested, a cell containing a manganese oxide electrode and a metallic lead electrode produced the highest power density (6.3 mW m(-2) ). However, this power density is still low relative to previously reported NaCl-based MEBs and heat recovery systems. This proof-of-concept study demonstrated that MEBs could indeed be used to generate electricity from AmB salinity gradients. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Common buffers, media, and stock solutions.

    PubMed

    2001-05-01

    This appendix describes the preparation of selected bacterial media and of buffers and reagents used in the manipulation of nucleic acids and proteins. Recipes for cell culture media and reagents are located elsewhere in the manual. RECIPES: Acids, concentrated stock solutions; Ammonium acetate, 10 M; Ammonium hydroxide, concentrated stock solution; ATP, 100 mM; BCIP, 5% (w/v); BSA (bovine serum albumin), 10% (100 mg/ml); Denhardt solution, 100x; dNTPs: dATP, dTTP, dCTP, and dGTP; DTT, 1 M; EDTA, 0.5 M (pH 8.0); Ethidium bromide solution; Formamide loading buffer, 2x; Gel loading buffer, 6x; HBSS (Hanks balanced salt solution); HCl, 1 M; HEPES-buffered saline, 2x; KCl, 1 M; LB medium; LB plates; Loading buffer; 2-ME, (2-mercaptoethanol)50 mM; MgCl(2), 1 M; MgSO(4), 1 M; NaCl, 5 M; NaOH, 10 M; NBT (nitroblue tetrazolium chloride), 5% (w/v); PCR amplification buffer, 10x; Phosphate-buffered saline (PBS), pH approximately 7.3; Potassium acetate buffer, 0.1 M; Potassium phosphate buffer, 0.1 M; RNase a stock solution (DNase-free), 2 mg/ml; SDS, 20%; SOC medium; Sodium acetate, 3 M; Sodium acetate buffer, 0.1 M; Sodium phosphate buffer, 0.1 M; SSC (sodium chloride/sodium citrate), 20x; SSPE (sodium chloride/sodium phosphate/EDTA), 20x; T4 DNA ligase buffer, 10x; TAE buffer, 50x; TBE buffer, 10x; TBS (Tris-buffered saline); TCA (trichloroacetic acid), 100% (w/v); TE buffer; Terrific broth (TB); TrisCl, 1 M; TY medium, 2x; Urea loading buffer, 2x.

  14. Revisiting analytical solutions for steady interface flow in subsea aquifers: Aquitard salinity effects

    NASA Astrophysics Data System (ADS)

    Werner, Adrian D.; Robinson, Neville I.

    2018-06-01

    Existing analytical solutions for the distribution of fresh groundwater in subsea aquifers presume that the overlying offshore aquitard, represented implicitly, contains seawater. Here, we consider the case where offshore fresh groundwater is the result of freshwater discharge from onshore aquifers, and neglect paleo-freshwater sources. A recent numerical modeling investigation, involving explicit simulation of the offshore aquitard, demonstrates that offshore aquitards more likely contain freshwater in areas of upward freshwater leakage to the sea. We integrate this finding into the existing analytical solutions by providing an alternative formulation for steady interface flow in subsea aquifers, whereby the salinity in the offshore aquitard can be chosen. The new solution, taking the aquitard salinity as that of freshwater, provides a closer match to numerical modeling results in which the aquitard is represented explicitly.

  15. Evaluation of PBS Treatment and PEI Coating Effects on Surface Morphology and Cellular Response of 3D-Printed Alginate Scaffolds.

    PubMed

    Mendoza García, María A; Izadifar, Mohammad; Chen, Xiongbiao

    2017-11-01

    Three-dimensional (3D) printing is an emerging technology for the fabrication of scaffolds to repair/replace damaged tissue/organs in tissue engineering. This paper presents our study on 3D printed alginate scaffolds treated with phosphate buffered saline (PBS) and polyethyleneimine (PEI) coating and their impacts on the surface morphology and cellular response of the printed scaffolds. In our study, sterile alginate was prepared by means of the freeze-drying method and then, used to prepare the hydrogel for 3D printing into calcium chloride, forming 3D scaffolds. Scaffolds were treated with PBS for a time period of two days and seven days, respectively, and PEI coating; then they were seeded with Schwann cells (RSC96) for the examination of cellular response (proliferation and differentiation). In addition, swelling and stiffness (Young's modulus) of the treated scaffolds was evaluated, while their surface morphology was assessed using scanning electron microscopy (SEM). SEM images revealed significant changes in scaffold surface morphology due to degradation caused by the PBS treatment over time. Our cell proliferation assessment over seven days showed that a two-day PBS treatment could be more effective than seven-day PBS treatment for improving cell attachment and elongation. While PEI coating of alginate scaffolds seemed to contribute to cell growth, Schwann cells stayed round on the surface of alginate over the period of cell culture. In conclusion, PBS-treatment may offer the potential to induce surface physical cues due to degradation of alginate, which could improve cell attachment post cell-seeding of 3D-printed alginate scaffolds.

  16. PbS nanosculptured thin film for phase retarder, anti-reflective, excellent absorber, polarizer and sensor applications

    NASA Astrophysics Data System (ADS)

    Chaudhary, Ashok; Klebanov, Matvey; Abdulhalim, Ibrahim

    2015-11-01

    Lead-sulphide (PbS) nanosculptured thin film (nSTF) is prepared using a glancing angle deposition (GLAD) technique and the physical vapour deposition (PVD) process. The morphology of the GLAD films clearly shows that an anisotropic structure is obtained and is composed of micro-sheets with sharp top edges (a few tens of nanometres tip width). Due to this anisotropy, optical birefringence is induced in the nSTF as well as linear dichroism. The structural and optical properties of the PbS nSTF have been characterized by scanning electron microscopy, atomic force microscopy, Raman spectroscopy and transmission measurements. The Raman spectra of PbS nSTF exhibit sharp peaks representative of vibrations in nano-crystalline PbS. Due to the absorption of PbS the nSTF is found to act as a linear polarizer with good extinction and contrast in the near infra-red range. Due to its porosity this nSTF also has the ability to sense fluids, which we demonstrate using ethanol-water solution at different concentrations. The combination of these effects in PbS nSTF is believed to constitute a prime candidate for many desirable device applications in different aspects with the low cost of production in large areas.

  17. Bio-sorbable, liquid electrolyte gated thin-film transistor based on a solution-processed zinc oxide layer.

    PubMed

    Singh, Mandeep; Palazzo, Gerardo; Romanazzi, Giuseppe; Suranna, Gian Paolo; Ditaranto, Nicoletta; Di Franco, Cinzia; Santacroce, Maria Vittoria; Mulla, Mohammad Yusuf; Magliulo, Maria; Manoli, Kyriaki; Torsi, Luisa

    2014-01-01

    Among the metal oxide semiconductors, ZnO has been widely investigated as a channel material in thin-film transistors (TFTs) due to its excellent electrical properties, optical transparency and simple fabrication via solution-processed techniques. Herein, we report a solution-processable ZnO-based thin-film transistor gated through a liquid electrolyte with an ionic strength comparable to that of a physiological fluid. The surface morphology and chemical composition of the ZnO films upon exposure to water and phosphate-buffered saline (PBS) are discussed in terms of the operation stability and electrical performance of the ZnO TFT devices. The improved device characteristics upon exposure to PBS are associated with the enhancement of the oxygen vacancies in the ZnO lattice due to Na(+) doping. Moreover, the dissolution kinetics of the ZnO thin film in a liquid electrolyte opens the possible applicability of these devices as an active element in "transient" implantable systems.

  18. Effect of dissolution of magnesium alloy AZ31 on the rheological properties of Phosphate Buffer Saline.

    PubMed

    Riaz, Usman; Rakesh, Leela; Shabib, Ishraq; Haider, Waseem

    2018-06-05

    The issue of long-term incompatible interactions associated with the permanent implants can be eliminated by using various biodegradable metal implants. The recent research is focusing on the use of degradable stents to restore most of the hindrances of capillaries, and coronary arteries by supplying instant blood flow with constant mechanical and structural support. However, internal endothelialization and infection due to the corrosion of implanted stents are not easy to diagnose in the long run. In the recent past, magnesium (Mg) has been widely investigated for the cardiovascular stent applications. Here we made an attempt to understand the biodegradation process of Mg alloy stent by studying the degradation of Mg alloy AZ31 (3 wt% Aluminum, 1 wt% Zn) powder at various time-intervals in simulated blood fluid using the Rheological methods. The degradability of the Mg stent in the arteries affects the stress-strain properties of blood plasma and the subsequent flow conditions. Blood and plasma viscosities alter due to the degradation of Mg resulting from the stress-strain experienced in the blood vessels, in which the stent is inserted. Here our objective was to explore the influence of Mg degradation on the blood plasma viscosity by studying the viscoelastic properties. In this work, the effect of dissolution of Mg alloy AZ31 on the rheological properties of Phosphate Buffer Saline (PBS) at various time intervals have been investigated. The viscosity of the PBS-AZ31 solution increased with the dissolution of both slurries and percolated clear solution. The only exception was day-7 of the percolated clear solution, where viscosity was decreased showing a reduction in viscosity at initial stages of dissolution. The frequency sweep showed the tendency of the PBS-AZ31 gelation up to 100 rad/s frequency. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Reduced Carrier Recombination in PbS - CuInS2 Quantum Dot Solar Cells

    PubMed Central

    Sun, Zhenhua; Sitbon, Gary; Pons, Thomas; Bakulin, Artem A.; Chen, Zhuoying

    2015-01-01

    Energy loss due to carrier recombination is among the major factors limiting the performance of TiO2/PbS colloidal quantum dot (QD) heterojunction solar cells. In this work, enhanced photocurrent is achieved by incorporating another type of hole-transporting QDs, Zn-doped CuInS2 (Zn-CIS) QDs into the PbS QD matrix. Binary QD solar cells exhibit a reduced charge recombination associated with the spatial charge separation between these two types of QDs. A ~30% increase in short-circuit current density and a ~20% increase in power conversion efficiency are observed in binary QD solar cells compared to cells built from PbS QDs only. In agreement with the charge transfer process identified through ultrafast pump/probe spectroscopy between these two QD components, transient photovoltage characteristics of single-component and binary QDs solar cells reveal longer carrier recombination time constants associated with the incorporation of Zn-CIS QDs. This work presents a straightforward, solution-processed method based on the incorporation of another QDs in the PbS QD matrix to control the carrier dynamics in colloidal QD materials and enhance solar cell performance. PMID:26024021

  20. Urinary composition predicts diuretic efficiency of hypertonic saline solution with furosemide therapy and heart failure prognosis.

    PubMed

    Ando, Tomotaka; Okuhara, Yoshitaka; Orihara, Yoshiyuki; Nishimura, Koichi; Yamamoto, Kyoko; Masuyama, Tohru; Hirotani, Shinichi

    2018-03-19

    Recently, we and other group have reported that furosemide administration along with hypertonic saline solution enhanced diuretic efficiency of furosemide. However, little is known about factors which associated with high diuretic efficiency by hypertonic saline solution with furosemide therapy. To identify predictors of diuretic efficiency in the hypertonic saline solution with furosemide therapy, we recruited 30 consecutive hospitalized heart failure (HF) patients with volume overload (77 ± 10 years, systolic blood pressure > 90 mmHg, and estimated glomerular filtration rate > 15 ml/min/1.73 m 2 ). Hypertonic saline with furosemide solution, consisting of 500 ml of 1.7% hypertonic saline solution with 40 mg of furosemide, was administered continuously over 24 h. The patients were divided into two groups on the basis of 24-h urine volume (UV) after initiation of diuretic treatment ≥ 2000 ml (high urine volume: HUV) and < 2000 ml (low urine volume: LUV). The basal clinical characteristics of both groups were analyzed and the predictors of HUV after receiving the treatment were identified. There were not significant differences between two groups in baseline clinical characteristics and medication. Univariate logistic analysis revealed that blood urea nitrogen/creatinine ratio, urine urea nitrogen/creatinine ratio (UUN/UCre), fractional excretion of sodium, and tricuspid annular plane systolic excursion positively associated with HUV. Multivariate logistic regression analysis revealed that UUN/UCre at baseline was independently associated with HUV, and UUN/UCre best predicts HUV by the therapy with a cut-off value of 6.16 g/dl/g Cre (AUC 0.910, 95% CI 0.696-0.999, sensitivity 80%, specificity 87%). The Kaplan-Meier curves revealed significant difference for HF rehospitalization and death rate at 180 days between patients with UUN/UCre ≥ 6.16 g/dl/g Cre and those with UUN/UCre < 6.16 g/dl/g Cre (log-rank P = 0

  1. Exposure to buffer solution alters tendon hydration and mechanics.

    PubMed

    Safa, Babak N; Meadows, Kyle D; Szczesny, Spencer E; Elliott, Dawn M

    2017-08-16

    A buffer solution is often used to maintain tissue hydration during mechanical testing. The most commonly used buffer solution is a physiological concentration of phosphate buffered saline (PBS); however, PBS increases the tissue's water content and decreases its tensile stiffness. In addition, solutes from the buffer can diffuse into the tissue and interact with its structure and mechanics. These bathing solution effects can confound the outcome and interpretation of mechanical tests. Potential bathing solution artifacts, including solute diffusion, and their effect on mechanical properties, are not well understood. The objective of this study was to measure the effects of long-term exposure of rat tail tendon fascicles to several concentrations (0.9-25%) of NaCl, sucrose, polyethylene glycol (PEG), and SPEG (NaCl+PEG) solutions on water content, solute diffusion, and mechanical properties. We found that with an increase in solute concentration the apparent water content decreased for all solution types. Solutes diffused into the tissue for NaCl and sucrose, however, no solute diffusion was observed for PEG or SPEG. The mechanical properties changed for both NaCl solutions, in particular after long-term (8h) incubation the modulus and equilibrium stress decreased compared to short-term (15min) for 25% NaCl, and the cross sectional area increased for 0.9% NaCl. However, the mechanical properties were unchanged for both PEG and SPEG except for minor alterations in stress relaxation parameters. This study shows that NaCl and sucrose buffer solutions are not suitable for long-term mechanical tests. We therefore propose using PEG or SPEG as alternative buffer solutions that after long-term incubation can maintain tissue hydration without solute diffusion and produce a consistent mechanical response. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Band-structure tailoring and surface passivation for highly efficient near-infrared responsive PbS quantum dot photovoltaics

    NASA Astrophysics Data System (ADS)

    Zhou, Ru; Niu, Haihong; Ji, Fengwei; Wan, Lei; Mao, Xiaoli; Guo, Huier; Xu, Jinzhang; Cao, Guozhong

    2016-11-01

    PbS is a promising light harvester for near-infrared (NIR) responsive quantum dot (QD) photovoltaics due to its narrow bulk band gap (0.41 eV) and large exciton Bohr radius (18 nm). However, the relatively low conduction band (CB) and high-density surface defects of PbS as two major drawbacks for its use in solar cells severely hamper the photovoltaic performance enhancement. In this work, a modified solution-based successive ionic layer adsorption and reaction (SILAR) utilizing mixed cationic precursors of Pb2+ and Cd2+ is explored, and such a scheme offers two benefits, band-structure tailoring and surface passivation. In-situ deposited CdS suppresses the excessive growth of PbS in the mesopores, thereby facilitating the favorable electron injection from PbS to TiO2 in view of the up-shifted CB level of QDs; the intimate interpenetration of two sulfides with each other leads to superior passivation of trap state defects on PbS, which suppresses the interfacial charge recombination. With the construction of photovoltaics based on such a hybrid (Pb,Cd)S/CdS configuration, impressive power conversion efficiency up to 4.08% has been reached, outperforming that of the conventional PbS/CdS pattern (2.95%). This work highlights the great importance of band-structure tailoring and surface passivation for constructing highly efficient PbS QD photovoltaics.

  3. Salinization of the soil solution decreases the further accumulation of salt in the root zone of the halophyte Atriplex nummularia Lindl. growing above shallow saline groundwater.

    PubMed

    Alharby, Hesham F; Colmer, Timothy D; Barrett-Lennard, Edward G

    2018-01-01

    Water use by plants in landscapes with shallow saline groundwater may lead to the accumulation of salt in the root zone. We examined the accumulation of Na + and Cl - around the roots of the halophyte Atriplex nummularia Lindl. and the impacts of this increasing salinity for stomatal conductance, water use and growth. Plants were grown in columns filled with a sand-clay mixture and connected at the bottom to reservoirs containing 20, 200 or 400 mM NaCl. At 21 d, Na + and Cl - concentrations in the soil solution were affected by the salinity of the groundwater, height above the water table and the root fresh mass density at various soil depths (P < 0.001). However, by day 35, the groundwater salinity and height above the water table remained significant factors, but the root fresh mass density was no longer significant. Regression of data from the 200 and 400 mM NaCl treatments showed that the rate of Na + accumulation in the soil increased until the Na + concentration reached ~250 mM within the root zone; subsequent decreases in accumulation were associated with decreases in stomatal conductance. Salinization of the soil solution therefore had a feedback effect on further salinization within the root zone. © 2017 John Wiley & Sons Ltd.

  4. Behavior of pure gallium in water and various saline solutions.

    PubMed

    Horasawa, N; Nakajima, H; Takahashi, S; Okabe, T

    1997-12-01

    This study investigated the chemical stability of pure gallium in water and saline solutions in order to obtain fundamental knowledge about the corrosion mechanism of gallium-based alloys. A pure gallium plate (99.999%) was suspended in 50 mL of deionized water, 0.01%, 0.1% or 1% NaCl solution at 24 +/- 2 degrees C for 1, 7, or 28 days. The amounts of gallium released into the solutions were determined by atomic absorption spectrophotometry. The surfaces of the specimens were examined after immersion by x-ray diffractometry (XRD) and x-ray photoelectron spectroscopy (XPS). In the solutions containing 0.1% or more NaCl, the release of gallium ions into the solution was lowered when compared to deionized water after 28-day immersion. Gallium oxide monohydroxide was found by XRD on the specimens immersed in deionized water after 28-day immersion. XPS indicated the formation of gallium oxide/hydroxide on the specimens immersed in water or 0.01% NaCl solution. The chemical stability of pure solid gallium was strongly affected by the presence of Cl- ions in the aqueous solution.

  5. Acid-base and hemodynamic status of patients with intraoperative hemorrhage using two solution types: Crystalloid Ringer lactate and 1.3% sodium bicarbonate in half-normal saline solution.

    PubMed

    Hashemi, Sayed Jalal; Heidari, Sayed Morteza; Yaraghi, Ahmad; Seirafi, Reza

    2016-01-01

    Intraoperative hemorrhage is one of the problems during surgery and, if it happens in a high volume without an immediate action to control, it can be fatal. Nowadays, various injectable solutions are used. The aim of this study was to compare the acid-base and hemodynamic status of the patient using two solutions, Ringer lactate and 1.3% sodium bicarbonate, in half saline solution. This clinical trial was performed at the Al-Zahra Hospital in 2013 on 66 patients who were randomly selected and put in two studied groups at the onset of hemorrhage. For the first group, crystalloid Ringer lactate solution and for the second group, 1.3% sodium bicarbonate in half-normal saline solution was used. Electrocardiogram, heart rate, O2 saturation non-invasive blood pressure and end-tidal CO2 were monitored. The arterial blood gas, blood electrolytes, glucose and blood urea nitrogen were measured before serum and blood injection. After the infusion of solutions and before blood transfusions, another sample was sent for measurement of blood parameters. Data were analyzed using SPSS software. The mean arterial pressure was significantly higher in the second group than in the first group at some times after the infusion of solutions. pHh levels, base excess, bicarbonate, sodium, strong ion differences and osmolarity were significantly greater and potassium and chloride were significantly lower in the second group than in the first group after the infusion of solutions. 1.3% sodium bicarbonate in half-normal saline solution can lead to a proper correction of hemodynamic instability. By maintaining hemodynamic status, osmolarity and electrolytes as well as better balance of acid-base, 1.3% sodium bicarbonate solution in half-normal saline solution can be more effective than Ringer lactate solution during intraoperative bleeding.

  6. The relationship between CDOM and salinity in estuaries: An analytical and graphical solution

    NASA Astrophysics Data System (ADS)

    Bowers, D. G.; Brett, H. L.

    2008-09-01

    The relationship between coloured dissolved organic matter (CDOM) and salinity in an estuary is explored using a simple box model in which the river discharge and concentration of CDOM in the river are allowed to vary with time. The results are presented as analytical and graphical solutions. The behaviour of the estuary depends upon the ratio, β, of the flushing time of the estuary to the timescale of the source variation. For small values of β, the variation in CDOM concentration in the estuary tracks that in the source, producing a linear relationship on a CDOM-salinity plot. As β increases, the estuary struggles to keep up with the changes in the source; and a curved CDOM-salinity plot results. For very large values of β, however, corresponding to estuaries with a long flushing time, the CDOM concentration in the estuary settles down to a mean value which again lies on a straight line on a CDOM-salinity plot (and extrapolates to the time-mean concentration in the source). The results are discussed in terms of the mapping of surface salinity in estuaries through the visible band remote sensing of CDOM.

  7. 2012 Preschool Pilot Study of PBS KIDS Transmedia Mathematics Content: A Report to the CPB-PBS "Ready to Learn Initiative"

    ERIC Educational Resources Information Center

    Pasnik, Shelley; Llorente, Carlin

    2012-01-01

    The 2012 Preschool Pilot Study of PBS KIDS Transmedia Mathematics Content (Preschool Pilot) is an important part of the authors' multiyear "Ready To Learn" (RTL) summative evaluation initiative. Through this initiative funded by the Corporation for Public Broadcasting (CPB) and Public Broadcasting Service (PBS), it was the responsibility…

  8. Biodegradable neural cell culture sheet made of poly(lactic-co-glycolic acid) thin film with micropatterns of Dulbecco’s phosphate-buffered saline (-) containing laminin layers

    NASA Astrophysics Data System (ADS)

    Nakamura, Yuki; Horiuchi, Shunpu; Nishioka, Yasushiro

    2018-02-01

    In the regenerative medicine field of nervous systems, techniques used to fabricate microstructures of neurons on flexible and biodegradable substrates have attracted attention. In this research, biodegradable and flexible neuron culture thin films that enable the selective axonal outgrowth of neurons were fabricated using poly(lactic-co-glycolic acid) (PLGA) thin films with micropatterns of Dulbecco’s phosphate-buffered saline (D-PBS) (-) containing laminin layers. The 100-µm-thick PLGA thin films were fabricated by diluting PLGA in acetone (5% w/w) and the solution was distributed onto a poly(dimethylsiloxane) (PDMS) mold. D-PBS (-) micropatterns containing laminin layers with widths of 10-150 µm were fabricated by micromolding in capillaries (MIMIC) and the microstencil method. Rat neurons were selectively cultured for 3 d on the laminin micropatterns; using the MIMIC method, the cells properly adhered to a pattern wider than 30 µm, while with the microstencil method, the necessary pattern width for proper adhesion was more than 50 µm.

  9. Irrigation solutions in open fractures of the lower extremities: evaluation of isotonic saline and distilled water.

    PubMed

    Olufemi, Olukemi Temiloluwa; Adeyeye, Adeolu Ikechukwu

    2017-01-01

    Open fractures are widely considered as orthopaedic emergencies requiring immediate intervention. The initial management of these injuries usually affects the ultimate outcome because open fractures may be associated with significant morbidity. Wound irrigation forms one of the pivotal principles in the treatment of open fractures. The choice of irrigation fluid has since been a source of debate. This study aimed to evaluate and compare the effects of isotonic saline and distilled water as irrigation solutions in the management of open fractures of the lower extremities. Wound infection and wound healing rates using both solutions were evaluated. This was a prospective hospital-based study of 109 patients who presented to the Accident and Emergency department with open lower limb fractures. Approval was sought and obtained from the Ethics Committee of the Hospital. Patients were randomized into either the isotonic saline (NS) or the distilled water (DW) group using a simple ballot technique. Twelve patients were lost to follow-up, while 97 patients were available until conclusion of the study. There were 50 patients in the isotonic saline group and 47 patients in the distilled water group. Forty-one (42.3%) of the patients were in the young and economically productive strata of the population. There was a male preponderance with a 1.7:1 male-to-female ratio. The wound infection rate was 34% in the distilled water group and 44% in the isotonic saline group (p = 0.315). The mean time ± SD to wound healing was 2.7 ± 1.5 weeks in the distilled water group and 3.1 ± 1.8 weeks in the isotonic saline group (p = 0.389). It was concluded from this study that the use of distilled water compares favourably with isotonic saline as an irrigation solution in open fractures of the lower extremities. © The Authors, published by EDP Sciences, 2017.

  10. Dielectric properties characterization of saline solutions by near-field microwave microscopy

    NASA Astrophysics Data System (ADS)

    Gu, Sijia; Lin, Tianjun; Lasri, Tuami

    2017-01-01

    Saline solutions are of a great interest when characterizations of biological fluids are targeted. In this work a near-field microwave microscope is proposed for the characterization of liquids. An interferometric technique is suggested to enhance measurement sensitivity and accuracy. The validation of the setup and the measurement technique is conducted through the characterization of a large range of saline concentrations (0-160 mg ml-1). Based on the measured resonance frequency shift and quality factor, the complex permittivity is successfully extracted as exhibited by the good agreement found when comparing the results to data obtained from Cole-Cole model. We demonstrate that the near field microwave microscope (NFMM) brings a great advantage by offering the possibility to select a resonance frequency and a quality factor for a given concentration level. This method provides a very effective way to largely enhance the measurement sensitivity in high loss materials.

  11. A simple route for making surfactant free lead sulfide (PbS) quantum dots

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alam, Firoz; Kumar, Neetesh; Dutta, Viresh, E-mail: vdutta@ces.iitd.ac.in

    2015-05-15

    Highlights: • Surfactant free PbS NCs were successfully synthesised using CoSP technique. • The technique eliminates the requirements of washing to remove the ligands. • Grinding using mortar and pestle creates well separated PbS QDs. • Surfactant free PbS NCs are stable and do not show any degradation with time. - Abstract: An efficient, cost effective and less time consuming method suitable for mass production of surfactant free quantum dots (QDs) of lead sulfide (PbS) is reported. PbS nanocrystals (NCs) are first synthesised by continuous spray pyrolysis (CoSP) technique and de-agglomeration into PbS quantum dots (QDs) is achieved by vigorousmore » mechanical grinding using mortar and pestle. Lead acetate and thiourea were used as the precursor materials for preparation of surfactant free PbS NCs. The broadening in XRD peaks of ground NCs as compared to as synthesized PbS NCs clearly indicated the reduction in particle size to be QDs of PbS. The TEM images also showed that ground PbS NCs were nearly spherical in shape having an average diameter in the range of 4–6 nm. The shift in optical gap from 0.41 eV to 1.47 eV supported the QD formation.« less

  12. Role of solute-transport models in the analysis of groundwater salinity problems in agricultural areas

    USGS Publications Warehouse

    Konikow, Leonard F.

    1981-01-01

    Undesirable salinity increases occur in both groundwater and surface water and are commonly related to agricultural practices. Groundwater recharge from precipitation or irrigation will transport and disperse residual salts concentrated by evapotranspiration, salts leached from soil and aquifer materials, as well as some dissolved fertilizers and pesticides. Where stream salinity is affected by agricultural practices, the increases in salt load usually are attributable mostly to a groundwater component of flow. Thus, efforts to predict, manage, or control stream salinity increases should consider the role of groundwater in salt transport. Two examples of groundwater salinity problems in Colorado, U.S.A., illustrate that a model which simulates accurately the transport and dispersion of solutes in flowing groundwater can be (1) a valuable investigative tool to help understand the processes and parameters controlling the movement and fate of the salt, and (2) a valuable management tool for predicting responses and optimizing the development and use of the total water resource. ?? 1981.

  13. Effect of container, vitrification volume and warming solution on cryosurvival of in vitro-produced bovine embryos.

    PubMed

    Rios, G L; Mucci, N C; Kaiser, G G; Alberio, R H

    2010-03-01

    The aim of the present research was to develop a low cost and easy to perform vitrification method for in vitro-produced cattle embryos. Effect of container material was evaluated (plastic straw compared to glass capillary, experiment 1), two volume sample (1 compared to 0.5 microL, experiment 2) and warming solution composition medium (Tissue Culture Medium 199 (TCM-199) compared to phosphate buffered saline (PBS), experiment 3) as modifications of the open pulled straw (OPS) system in order to reduce embryo damage caused by exposure to cold. In all experiments, day 7 and expanded blastocysts of cattle were exposed to the vitrification solution 1 for 3 min and 30s in solution 2. After this, embryos were placed in a droplet and loaded in a narrow end container, and immediately submerged into liquid nitrogen. For warming, vitrified embryos were plunged into warming solution 1 for 3 min, and transferred into warming solution 2 for 1 min. Fresh embryos kept in culture were used as control group. Hatching rates were recorded in all cases at day 13. In experiment 1 there was no significant effect of container material on hatching rates. Postwarming survival rate of vitrified embryos was lower than control (27.5% plastic straws, 18.9% glass capillary and 80.5% control, P<0.05). In experiment 2, there was no significant effect of volume in hatching rates (58.3% 1 microL, 61.3% 0.5 microL and 80.5% control, P<0.05). In experiment 3, the composition of the holding medium of warming solution influenced hatching rates (84.1% TCM-199, 74.8% PBS and 91.1% control P<0.05). These data suggest that neither glass capillaries nor reduced sample volume could improve hatching rates after vitrification-warming with open pulled straw (OPS) procedure, and that PBS can replace TCM-199 in warming solutions, but lesser hatching rates should be expected.

  14. The PBS in a globalised world: free trade and reference pricing.

    PubMed

    Searles, Andrew

    2009-05-01

    In January 2005 Australia implemented the Australia-United States Free Trade Agreement (AUSFTA). The agreement had placed domestic health policy and the Pharmaceutical Benefits Scheme (PBS) in particular, on the trade negotiating table. At the time Australians were told the PBS would not be undermined, but why was it included in a trade agreement? This article argues that recent reforms to the PBS partially delivered on an issue that the US has compelled its trade negotiators to ensure since 2002: the elimination of reference pricing. In Australia, reference pricing, as used by the PBS, had been credited with obtaining money when buying new medicines.

  15. Charge Carrier Conduction Mechanism in PbS Quantum Dot Solar Cells: Electrochemical Impedance Spectroscopy Study.

    PubMed

    Wang, Haowei; Wang, Yishan; He, Bo; Li, Weile; Sulaman, Muhammad; Xu, Junfeng; Yang, Shengyi; Tang, Yi; Zou, Bingsuo

    2016-07-20

    With its properties of bandgap tunability, low cost, and substrate compatibility, colloidal quantum dots (CQDs) are becoming promising materials for optoelectronic applications. Additionally, solution-processed organic, inorganic, and hybrid ligand-exchange technologies have been widely used in PbS CQDs solar cells, and currently the maximum certified power conversion efficiency of 9.9% has been reported by passivation treatment of molecular iodine. Presently, there are still some challenges, and the basic physical mechanism of charge carriers in CQDs-based solar cells is not clear. Electrochemical impedance spectroscopy is a monitoring technology for current by changing the frequency of applied alternating current voltage, and it provides an insight into its electrical properties that cannot be measured by direct current testing facilities. In this work, we used EIS to analyze the recombination resistance, carrier lifetime, capacitance, and conductivity of two typical PbS CQD solar cells Au/PbS-TBAl/ZnO/ITO and Au/PbS-EDT/PbS-TBAl/ZnO/ITO, in this way, to better understand the charge carriers conduction mechanism behind in PbS CQD solar cells, and it provides a guide to design high-performance quantum-dots solar cells.

  16. Absolute Salinity, ''Density Salinity'' and the Reference-Composition Salinity Scale: present and future use in the seawater standard TEOS-10

    NASA Astrophysics Data System (ADS)

    Wright, D. G.; Pawlowicz, R.; McDougall, T. J.; Feistel, R.; Marion, G. M.

    2011-01-01

    Salinity plays a key role in the determination of the thermodynamic properties of seawater and the new TEOS-101 standard provides a consistent and effective approach to dealing with relationships between salinity and these thermodynamic properties. However, there are a number of practical issues that arise in the application of TEOS-10, both in terms of accuracy and scope, including its use in the reduction of field data and in numerical models. First, in the TEOS-10 formulation for IAPSO Standard Seawater, the Gibbs function takes the Reference Salinity as its salinity argument, denoted SR, which provides a measure of the mass fraction of dissolved material in solution based on the Reference Composition approximation for Standard Seawater. We discuss uncertainties in both the Reference Composition and the Reference-Composition Salinity Scale on which Reference Salinity is reported. The Reference Composition provides a much-needed fixed benchmark but modified reference states will inevitably be required to improve the representation of Standard Seawater for some studies. However, the Reference-Composition Salinity Scale should remain unaltered to provide a stable representation of salinity for use with the TEOS-10 Gibbs function and in climate change detection studies. Second, when composition anomalies are present in seawater, no single salinity variable can fully represent the influence of dissolved material on the thermodynamic properties of seawater. We consider three distinct representations of salinity that have been used in previous studies and discuss the connections and distinctions between them. One of these variables provides the most accurate representation of density possible as well as improvements over Reference Salinity for the determination of other thermodynamic properties. It is referred to as "Density Salinity" and is represented by the symbol SAdens; it stands out as the most appropriate representation of salinity for use in dynamical physical

  17. Absolute Salinity, "Density Salinity" and the Reference-Composition Salinity Scale: present and future use in the seawater standard TEOS-10

    NASA Astrophysics Data System (ADS)

    Wright, D. G.; Pawlowicz, R.; McDougall, T. J.; Feistel, R.; Marion, G. M.

    2010-08-01

    Salinity plays a key role in the determination of the thermodynamic properties of seawater and the new TEOS-101 standard provides a consistent and effective approach to dealing with relationships between salinity and these thermodynamic properties. However, there are a number of practical issues that arise in the application of TEOS-10, both in terms of accuracy and scope, including its use in the reduction of field data and in numerical models. First, in the TEOS-10 formulation for IAPSO Standard Seawater, the Gibbs function takes the Reference Salinity as its salinity argument, denoted SR, which provides a measure of the mass fraction of dissolved material in solution based on the Reference Composition approximation for Standard Seawater. We discuss uncertainties in both the Reference Composition and the Reference-Composition Salinity Scale on which Reference Salinity is reported. The Reference Composition provides a much-needed fixed benchmark but modified reference states will inevitably be required to improve the representation of Standard Seawater for some studies. The Reference-Composition Salinity Scale should remain unaltered to provide a stable representation of salinity for use with the TEOS-10 Gibbs function and in climate change detection studies. Second, when composition anomalies are present in seawater, no single salinity variable can fully represent the influence of dissolved material on the thermodynamic properties of seawater. We consider three distinct representations of salinity that have been used in previous studies and discuss the connections and distinctions between them. One of these variables provides the most accurate representation of density possible as well as improvements over Reference Salinity for the determination of other thermodynamic properties. It is referred to as "Density Salinity" and is represented by the symbol SAdens; it stands out as the most appropriate representation of salinity for use in dynamical physical

  18. New Deoxyribonucleic Acid Polymerase Induced by Bacillus subtilis Bacteriophage PBS2

    PubMed Central

    Price, Alan R.; Cook, Sandra J.

    1972-01-01

    The deoxyribonucleic acid (DNA) of Bacillus subtilis phage PBS2 has been confirmed to contain uracil instead of thymine. PBS2 phage infection of wild-type cells or DNA polymerase-deficient cells results in an increase in the specific activity of DNA polymerase. This induction of DNA polymerase activity is prevented by actinomycin D and chloramphenicol. In contrast to the major B. subtilis DNA polymerase, which prefers deoxythymidine triphosphate (dTTP) to deoxyuridine triphosphate (dUTP), the DNA polymerase in crude extracts of PBS2-infected cells is equally active whether dTTP or dUTP is employed. This phage-induced polymerase may be responsible for the synthesis of uracil-containing DNA during PBS2 phage infection. PMID:4623224

  19. Finding a solution: Heparinised saline versus normal saline in the maintenance of invasive arterial lines in intensive care.

    PubMed

    Everson, Matthew; Webber, Lucy; Penfold, Chris; Shah, Sanjoy; Freshwater-Turner, Dan

    2016-11-01

    We assessed the impact of heparinised saline versus 0.9% normal saline on arterial line patency. Maintaining the patency of arterial lines is essential for obtaining accurate physiological measurements, enabling blood sampling and minimising line replacement. Use of heparinised saline is associated with risks such as thrombocytopenia, haemorrhage and mis-selection. Historical studies draw variable conclusions but suggest that normal saline is at least as effective at maintaining line patency, although recent evidence has questioned this. We conducted a prospective analysis of the use of heparinised saline versus normal saline on unselected patients in the intensive care of our hospital. Data concerning duration of 471 lines insertion and reason for removal was collected. We found a higher risk of blockage for lines flushed with normal saline compared with heparinised saline (RR = 2.15, 95% CI 1.392-3.32, p  ≤ 0.001). Of the 56 lines which blocked initially (19 heparinised saline and 37 normal saline lines), 16 were replaced with new lines; 5 heparinised saline lines and 11 normal saline lines were reinserted; 5 of these lines subsequently blocked again, 3 of which were flushed with normal saline. Our study demonstrates a clinically important reduction in arterial line longevity due to blockages when flushed with normal saline compared to heparinised saline. We have determined that these excess blockages have a significant clinical impact with further lines being inserted after blockage, resulting in increased risks to patients, wasted time and cost of resources. Our findings suggest that the current UK guidance favouring normal saline flushes should be reviewed.

  20. Stability of solutions of antineoplastic agents during preparation and storage for in vitro assays. General considerations, the nitrosoureas and alkylating agents.

    PubMed

    Bosanquet, A G

    1985-01-01

    In vitro drug sensitivity of tumour biopsies is currently being determined using a variety of methods. For these chemosensitivity assays many drugs are required at short notice, and this in turn means that the drugs must generally be stored in solution. There are, however, a number of potential problems associated with dissolving and storing drugs for in vitro use, which include (a) drug adsorption; (b) effects of freezing; (c) drug stability under the normal conditions of dilution and setting up of an in vitro assay; and (d) insolubility of drugs in normal saline (NS) or phosphate-buffered saline (PBS). These problems are considered in general, and some recommendations for use of solutions of drugs in in vitro assays are suggested. The nitrosoureas and alkylating agents are also investigated in greater detail in this respect. The nitrosoureas are found to be very labile in PBS at pH 7, with 5% degradation (t0.95) occurring in 10-50 min at room temperature. These values are increased about 10-fold on refrigeration and about 5- to 10-fold on reduction of the pH of the medium to pH 4-5. At pH 7 and room temperature, t0.95 is observed in under 1 h with the alkylating agents nitrogen mustard, chlorambucil, melphalan, 2,5-diaziridinyl-3,6-bis(2-hydroxyethylamino)-1,4-benzoquinone (BZQ), dibromodulcitol, dibromomannitol, treosulphan, and procarbazine. Of the other alkylating agents, 4-hydroperoxycylophosphamide (sometimes used in vitro in place of cyclophosphamide), busulphan, dianhydrogalactitol, aziridinylbenzoquinone (AZQ), and dacarbazine have a t0.95 of between 2 and 24 h, while ifosfamide and pentamethylmelamine are both stable in aqueous solution for greater than 7 days. About half the drugs studied in detail have been stored frozen in solution for in vitro use, although very little is known about their stability under these conditions.

  1. Thermodynamic nonequilibrium phase change behavior and thermal properties of biological solutions for cryobiology applications.

    PubMed

    Han, Bumsoo; Bischof, John C

    2004-04-01

    Understanding the phase change behavior of biomaterials during freezing/thawing including their thermal properties at low temperatures is essential to design and improve cryobiology applications such as cryopreservation and cryosurgery. However, knowledge of phase change behavior and thermal properties of various biomaterials is still incomplete, especially at cryogenic temperatures (< or = -40 degrees C). Moreover, in these applications, chemicals are often added to improve their outcome, which can result in significant variation in the phase change behavior and thermal properties from those of the original biomaterials. These chemical additives include cryoprotective agents (CPAs), antifreeze protein (AFP), or cryosurgical adjuvants like sodium chloride (NaCl). In the present study, phase change behavior and thermal properties of saline solutions--either water-NaCl or phosphate buffered saline (PBS)--with various chemical additives were investigated. The chemical additives studied are glycerol and raffinose as CPAs, an AFP (Type III, molecular weight = 6500), and NaCl as a cryosurgical adjuvant. The phase change behavior was investigated using a differential scanning calorimeter (DSC) and a cryomicroscope. The specific and latent heat of these solutions were also measured with the DSC. The saline solutions have two distinct phase changes--water/ice and eutectic phase changes. During freezing, eutectic solidification of both water-NaCl and PBS are significantly supercooled below their thermodynamic equilibrium eutectic temperatures. However, their melting temperatures are close to thermodynamic equilibrium during thawing. These eutectic phase changes disappear when even a small amount (0.1 M glycerol) of CPA was added, but they are still observed after the addition of an AFP. The specific heats of these solutions are close to that of ice at very low temperatures (< or = -100 degrees C) regardless of the additives, but they increase between -100 degrees C and -30

  2. Metal-passivated PbS nanoparticles: fabrication and characterization.

    PubMed

    Tchaplyguine, M; Mikkelä, M-H; Mårsell, E; Polley, C; Mikkelsen, A; Zhang, W; Yartsev, A; Hetherington, C J D; Wallenberg, L R; Björneholm, O

    2017-03-08

    Organic-shell-free PbS nanoparticles have been produced in the size range relevant for quantum-dot solar cells (QDSCs) by a vapor aggregation method involving magnetron reactive sputtering. This method creates a beam of free 5-10 nm particles in a vacuum. The dimensions of the particles were estimated after their deposition on a substrate by imaging them using ex situ SEM and HRTEM electron microscopy. The particle structure and chemical composition could be deduced "on the fly", prior to deposition, using X-ray photoelectron spectroscopy (XPS) with tunable synchrotron radiation. Our XPS results suggest that under certain conditions it is possible to fabricate particles with a semiconductor core and 1 to 2 monolayer shells of metallic lead. For this case the absolute energy of the highest occupied molecular orbital (HOMO) in PbS has been determined to be (5.0 ± 0.5) eV below the vacuum level. For such particles deposited on a substrate HRTEM has confirmed the XPS-based conclusions on the crystalline PbS structure of the semiconductor core. Absorption spectroscopy on the deposited film has given a value of ∼1 eV for the lowest exciton. Together with the valence XPS results this has allowed us to reconstruct the energy level scheme of the particles. The results obtained are discussed in the context of the properties of PbS QDSCs.

  3. Effects of solutions treated with oxygen radicals in neutral pH region on inactivation of microorganism

    NASA Astrophysics Data System (ADS)

    Kobayashi, Tsuyoshi; Hashizume, Hiroshi; Ohta, Takayuki; Ishikawa, Kenji; Hori, Masaru; Ito, Masafumi

    2015-09-01

    The inactivation of microorganisms using nonequilbrium atmospheric pressure plasmas has been attracted much attention due to the low temperature processing and high speed treatment. In this study, we have inactivated E. coli suspended in solutions with neutral pH using an atmospheric-pressure oxygen radical source which can selectively supply electrically neutral oxygen radicals. E. coli cells were suspended with deionized distilled water (DDW) (pH = 6.8) or phosphate buffered saline (PBS) (pH = 7.4) or Citrate-Na buffer (pH = 6.5). The treated samples were diluted and spread on nutrient agar (Nutrient Broth). They were cultured at 37° C. The inactivation effects of oxygen radicals on those cells in solutions were evaluated by colony-counting method. O2 diluted by Ar gas were employed as a working gas for the radical source. The total gas flow rate and the gas mixture ratio of O2/(Ar + O2) were set at 5 slm and 0.6%, respectively. The distance between the radical exit and the suspension surface were set at 10 mm. As a result, the D values for DDW(pH = 6.8), PBS(pH = 7.4) and Citrate-Na buffer(pH = 6.5) were estimated to be 1.4 min, 0.9 min and 16.8 min respectively. The inactivation rates in DDW, PBS were significantly different from that in Citrate-Na buffer. This work was partly supported by JSPS KAKENHI Grant Number 26286072 and project for promoting Research Center in Meijo University.

  4. Study of the back recombination processes of PbS quantum dots sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Badawi, Ali; Al-Hosiny, N.; Merazga, Amar; Albaradi, Ateyyah M.; Abdallah, S.; Talaat, H.

    2016-12-01

    In this study, the back recombination processes of PbS quantum dots sensitized solar cells (QDSSCs) has been investigated. PbS QDs were adsorbed onto titania electrodes to act the role of sensitizers using successive ionic layer adsorption and reaction (SILAR) technique. The energy band gaps of the synthesized PbS QDs/titania are ranged from 1.64 eV (corresponding to 756 nm) to 3.12 eV (397 nm) matching the whole visible solar spectrum. The hyperbolic band model (HBM) was used to calculate PbS QDs size and it ranges from 1.76 to 3.44 nm. The photovoltaic parameters (open circuit voltage Voc, short circuit current density Jsc, fill factor FF and efficiency η) of the assembled PbS QDs sensitized solar cells (QDSSCs) were determined under a solar illumination of 100 mW/cm2 (AM 1.5 conditions). The open circuit voltage-decay (OCVD) rates of the assembled PbS QDSSCs were measured. The time constant (τ) for PbS QDSSCs (4 SILAR cycles) shows one order of magnitude larger than that of PbS QDSSCs (8 SILAR cycles) as a result of a decreased electron-hole back recombination.

  5. Hybrid polymer/ZnO solar cells sensitized by PbS quantum dots

    PubMed Central

    2012-01-01

    Poly[2-methoxy-5-(2-ethylhexyloxy-p-phenylenevinylene)]/ZnO nanorod hybrid solar cells consisting of PbS quantum dots [QDs] prepared by a chemical bath deposition method were fabricated. An optimum coating of the QDs on the ZnO nanorods could strongly improve the performance of the solar cells. A maximum power conversion efficiency of 0.42% was achieved for the PbS QDs' sensitive solar cell coated by 4 cycles, which was increased almost five times compared with the solar cell without using PbS QDs. The improved efficiency is attributed to the cascade structure formed by the PbS QD coating, which results in enhanced open-circuit voltage and exciton dissociation efficiency. PMID:22313746

  6. Unknown Aspects of Self-Assembly of PbS Microscale Superstructures

    PubMed Central

    Querejeta-Fernández, Ana; Hernández-Garrido, Juan C.; Yang, Hengxi; Zhou, Yunlong; Varela, Aurea; Parras, Marina; Calvino-Gámez, José J.; González-Calbet, Jose M.; Green, Peter F.; Kotov, Nicholas A.

    2012-01-01

    A lot of interesting and sophisticated examples of nanoparticle (NP) self-assembly (SA) are known. From both fundamental and technological standpoints this field requires advancements in three principle directions: a) understanding the mechanism and driving forces of three-dimensional (3D) SA with both nano- and micro-levels of organization; b) understanding of disassembly/deconstruction processes; and c) finding synthetic methods of assembly into continuous superstructures without insulating barriers. From this perspective, we investigated the formation of well-known star-like PbS superstructures and found a number of previously unknown or overlooked aspects that can advance the knowledge of NP self-assembly in these three directions. The primary one is that the formation of large seemingly monocrystalline PbS superstructures with multiple levels of octahedral symmetry can be explained only by SA of small octahedral NPs. We found five distinct periods in the formation PbS hyperbranched stars: 1) nucleation of early PbS NPs with an average diameter of 31 nm; 2) assembly into 100–500 nm octahedral mesocrystals; 3) assembly into 1000–2500 nm hyperbranched stars; 4) assembly and ionic recrystallization into six-arm rods accompanied by disappearance of fine nanoscale structure; 5) deconstruction into rods and cubooctahedral NPs. The switches in assembly patterns between the periods occur due to variable dominance of pattern–determining forces that include vander Waals and electrostatic (charge-charge, dipole-dipole, and polarization) interactions. The superstructure deconstruction is triggered by chemical changes in the deep eutectic solvent (DES) used as the media. PbS superstructures can be excellent models for fundamental studies of nanoscale organization and SA manufacturing of (opto)electronics and energy harvesting devices which require organization of PbS components at multiple scales. PMID:22515512

  7. Unknown aspects of self-assembly of PbS microscale superstructures.

    PubMed

    Querejeta-Fernández, Ana; Hernández-Garrido, Juan C; Yang, Hengxi; Zhou, Yunlong; Varela, Aurea; Parras, Marina; Calvino-Gámez, José J; González-Calbet, Jose M; Green, Peter F; Kotov, Nicholas A

    2012-05-22

    A lot of interesting and sophisticated examples of nanoparticle (NP) self-assembly (SA) are known. From both fundamental and technological standpoints, this field requires advancements in three principle directions: (a) understanding the mechanism and driving forces of three-dimensional (3D) SA with both nano- and microlevels of organization; (b) understanding disassembly/deconstruction processes; and (c) finding synthetic methods of assembly into continuous superstructures without insulating barriers. From this perspective, we investigated the formation of well-known star-like PbS superstructures and found a number of previously unknown or overlooked aspects that can advance the knowledge of NP self-assembly in these three directions. The primary one is that the formation of large seemingly monocrystalline PbS superstructures with multiple levels of octahedral symmetry can be explained only by SA of small octahedral NPs. We found five distinct periods in the formation PbS hyperbranched stars: (1) nucleation of early PbS NPs with an average diameter of 31 nm; (2) assembly into 100-500 nm octahedral mesocrystals; (3) assembly into 1000-2500 nm hyperbranched stars; (4) assembly and ionic recrystallization into six-arm rods accompanied by disappearance of fine nanoscale structure; (5) deconstruction into rods and cuboctahedral NPs. The switches in assembly patterns between the periods occur due to variable dominance of pattern-determining forces that include van der Waals and electrostatic (charge-charge, dipole-dipole, and polarization) interactions. The superstructure deconstruction is triggered by chemical changes in the deep eutectic solvent (DES) used as the media. PbS superstructures can be excellent models for fundamental studies of nanoscale organization and SA manufacturing of (opto)electronics and energy-harvesting devices which require organization of PbS components at multiple scales.

  8. Staying True to Our PBS Roots in a Changing World

    ERIC Educational Resources Information Center

    Kincaid, Don

    2018-01-01

    The field of Positive Behavior Support (PBS) has grown and changed significantly in the past 25 years and should be expected to continue that trend for the next 25 years. These changes cannot always be predicted, but they can be managed by considering some current changes to the definition of PBS (Kincaid et al., 2016). This paper discussed how…

  9. Molecular characterization of Fagaceae species using inter-primer binding site (iPBS) markers.

    PubMed

    Coutinho, João Paulo; Carvalho, Ana; Martín, Antonio; Lima-Brito, José

    2018-04-01

    Retrotransposons (RTNs) contribute for genome evolution, influencing its size and structure. We investigated the utility of the RTN-based markers inter-primer binding site (iPBS) for the molecular characterization of 25 Fagaceae species from genera Castanea, Fagus and Quercus. The assessment of genetic diversity, relationships and structure, as well as taxonomic classification of Fagaceae based on molecular data is important for definition of conservation, forestry management strategies and discrimination among natural hybrids and their parents since natural hybridization may increase with the climate changes. Here, iPBS primers designed by other authors were tested alone and combined. Some of them were discriminative, revealed polymorphism within and among taxa allowing the production of a total of 150 iPBS markers. In addition, several monomorphic iPBS markers were also amplified in each taxon. The UPGMA dendrogram based on the pooled iPBS data revealed 27% of genetic similarity among species. The individuals were clustered per genus and most of the oaks per infrageneric group corroborating the adopted taxonomy. Globally, the iPBS markers demonstrated suitability for DNA fingerprinting, determination of phylogenies and taxonomic discrimination in Fagaceae, and could constitute a useful and alternative tool for germplasm characterization, and for definition of conservation strategies and forestry management. Moreover, these markers would be useful for fingerprinting natural hybrids that share morphological similarities with their parents. Since iPBS markers could also enable insights about RTNs evolution, an eventual correlation among iPBS polymorphism, variability of RTN insertions and/or genome size in Fagaceae is discussed.

  10. Investigation of colloidal PbS quantum dot-based solar cells with near infrared emission.

    PubMed

    Lim, Sungoh; Kim, Yohan; Lee, Jeongno; Han, Chul Jong; Kang, Jungwon; Kim, Jiwan

    2014-12-01

    Colloidal quantum dots (QD)-based solar cells with near infrared (NIR) emission have been investigated. Lead sulfide (PbS) QDs, which have narrow band-gap and maximize the absorption of NIR spectrum, were chosen as active materials for efficient solar cells. The inverted structure of indium tin oxide/titanium dioxide/PbS QDs/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)/silver (ITO/TiO2/PbS QDs/ PSS/Ag) was applied for favorable electron and hole seperation from the PbS QD. Through the ligand exchange by 1,2-Ethanedithiol (EDT), the interparticle distance of the PbS QDs in thin film became closer and the performance of the PbS QD-based solar cells was improved. Our PbS QD-based inverted solar cells showed open circuit voltages (V(oc)) of 0.33 V, short circuit current density (J(sc)) of 10.89 mA/cm2, fill factor (FF) of 30%, and power conversion efficiency (PCE) of 1.11%. In our PbS QD-based multifunctional solar cell, the NIR light emission intensity was simply detected with photodiode system, which implies the potential of multi-functional diode device for various applications.

  11. Corrosion of dental aluminium bronze in neutral saline and saline lactic acid.

    PubMed

    Tibballs, J E; Erimescu, Raluca

    2006-09-01

    To compare the corrosion behaviours of two aluminium bronze, dental casting alloys during a standard immersion test and for immersion in neutral saline. Cast specimens of aluminium bronzes with 1.4 wt% Fe (G) and 4 wt% Fe (N) were subject to progressively longer periods (up to in total 7 days) immersed in 0.1 M saline, 0.1 M lactic acid solutions and examined by scanning electron microscopy with EDX analysis. Immersion in 0.1M neutral saline was for 7 days. In the acidic solution, exposed interdendritic volumes in alloy N corroded completely away in 7 days with dissolution of Ni-enriched precipitate species as well as the copper-rich matrix. Alloy G begins to corrode more slowly but by a similar mechanism. The number density of an Fe-enriched species is insufficient to maintain a continuous galvanic potential to the copper matrix, and dissolution becomes imperceptible. In neutral saline solution, galvanic action alone caused pit-etching, without the dissolution of either precipitate species. The upper limit for the total dissolution of metallic ions in the standard immersion test can be set at 200 microg cm(-2). Aluminium bronze dental alloys can be expected to release both copper and nickel ions into an acidic oral environment.

  12. Usefulness of underwater endoscopic submucosal dissection in saline solution with a monopolar knife for colorectal tumors (with videos).

    PubMed

    Nagata, Mitsuru

    2018-05-01

    Generally, colorectal endoscopic submucosal dissection (ESD) is performed with a monopolar knife with CO 2 supply from an endoscope. There are few case reports about underwater ESD (UESD) in saline solution with a bipolar knife. The usefulness and safety of UESD in saline solution with a monopolar knife are unclear. The present study aimed to investigate the usefulness and safety of UESD in saline solution with a monopolar knife for colorectal tumors. This retrospective, observational study on UESD for colorectal tumors included 26 colorectal tumors from 24 patients treated with UESD at our department between October 2015 and February 2017. The characteristics of patients, factors associated with ESD difficulty, treatment results, and variations in blood test data before and after UESD were analyzed. En bloc resection was successful in all lesions without any serious adverse events. The median major diameter of the resected specimens was 30 mm (interquartile range [IQR], 28-35) and of the tumor 22.5 mm (IQR, 17.8-25.3). The median procedure time was 60 minutes (IQR, 45-111) and median speed of dissection 10.4 mm 2 /min (IQR, 6.4-12.2). No cases of perforation occurred. Post-ESD bleeding occurred in only 1 case, and endoscopic hemostasis was achieved. There was no case of electrolyte imbalance requiring treatment after UESD. UESD in saline solution with a monopolar knife for colorectal tumors is useful and safe. UESD has potential advantages that should be further assessed. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  13. Comparison of the in vitro effects of saline, hypertonic hydroxyethyl starch, hypertonic saline, and two forms of hydroxyethyl starch on whole blood coagulation and platelet function in dogs.

    PubMed

    Wurlod, Virginie A; Howard, Judith; Francey, Thierry; Schweighauser, Ariane; Adamik, Katja N

    2015-01-01

    To compare the in vitro effects of hypertonic solutions and colloids to saline on coagulation in dogs. In vitro experimental study. Veterinary teaching hospital. Twenty-one adult dogs. Blood samples were diluted with saline, 7.2% hypertonic saline solution with 6% hydroxyethylstarch with an average molecular weight of 200 kDa and a molar substitution of 0.4 (HH), 7.2% hypertonic saline (HTS), hydroxyethyl starch (HES) 130/0.4 or hydroxyethyl starch 600/0.75 at ratios of 1:22 and 1:9, and with saline and HES at a ratio of 1:3. Whole blood coagulation was analyzed using rotational thromboelastometry (extrinsic thromboelastometry-cloting time (ExTEM-CT), maximal clot firmness (MCF) and clot formation time (CFT) and fibrinogen function TEM-CT (FibTEM-CT) and MCF) and platelet function was analyzed using a platelet function analyzer (closure time, CTPFA ). All parameters measured were impaired by saline dilution. The CTPFA was prolonged by 7.2% hypertonic saline solution with 6% hydroxyethylstarch with an average molecular weight of 200 kDa and a molar substitution of 0.4 (HH) and HTS but not by HES solutions. At clinical dilutions equivalent to those generally administered for shock (saline 1:3, HES 1:9, and hypertonic solutions 1:22), CTPFA was more prolonged by HH and HTS than other solutions but more by saline than HES. No difference was found between the HES solutions or the hypertonic solutions. ExTEM-CFT and MCF were impaired by HH and HTS but only mildly by HES solutions. At clinically relevant dilutions, no difference was found in ExTEM-CFT between HTS and saline or in ExTEM-MCF between HH and saline. No consistent difference was found between the 2 HES solutions but HH impaired ExTEM-CFT and MCF more than HTS. At high dilutions, FibTEM-CT and -MCF and ExTEM-CT were impaired by HES. Hypertonic solutions affect platelet function and whole blood coagulation to a greater extent than saline and HES. At clinically relevant dilutions, only CTPFA was markedly more

  14. PBS TeacherLine National Survey of Teacher Professional Development, 2005-2006

    ERIC Educational Resources Information Center

    Hezel Associates (NJ1), 2007

    2007-01-01

    PBS TeacherLine, an initiative funded under the U.S. Department of Education's Ready To Teach program, is designed to provide high-quality online professional development for K-12 teachers. Through the first five-year grant cycle, ending in 2005, PBS TeacherLine produced approximately 100 online facilitated courses in reading, mathematics,…

  15. Nongeminate Radiative Recombination of Free Charges in Cation-Exchanged PbS Quantum Dot Films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Marshall, Ashley R.; Beard, Matthew C.; Johnson, Justin C.

    2016-06-01

    Using photoluminescence (PL) spectroscopy we explore the radiative recombination pathways in PbS quantum dots (QDs) synthesized by two methods. We compare conventionally synthesized PbS from a PbO precursor to PbS synthesized using cation-exchange from CdS QDs. We show that strongly coupled films of PbS QDs from the cation-exchange luminesce with significant efficiency at room temperature. This is in stark contrast to conventional PbS QDs, which have exceedingly weak room temperature emission. Moreover, the power dependence of the emission is quadratic, indicating bimolecular radiative recombination that is reasonably competitive with trap-assisted recombination, a feature previously unreported in coupled PbS QD films.more » We interpret these results in terms of a greatly reduced defect concentration for cation-exchanged QDs that mitigates the influence of trap-assisted recombination. Cation-exchanged QDs have recently been employed in highly efficient and air-stable lead chalcogenide QD devices, and the reduced number of trap states inferred here may lead to improved current collection and higher open circuit voltage.« less

  16. Nongeminate radiative recombination of free charges in cation-exchanged PbS quantum dot films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Marshall, Ashley R.; Beard, Matthew C.; Johnson, Justin C.

    2016-06-01

    Using photoluminescence (PL) spectroscopy we explore the radiative recombination pathways in PbS quantum dots (QDs) synthesized by two methods. We compare conventionally synthesized PbS from a PbO precursor to PbS synthesized using cation-exchange from CdS QDs. We show that strongly coupled films of PbS QDs from the cation-exchange luminesce with significant efficiency at room temperature. This is in stark contrast to conventional PbS QDs, which have exceedingly weak room temperature emission. Moreover, the power dependence of the emission is quadratic, indicating bimolecular radiative recombination that is reasonably competitive with trap-assisted recombination, a feature previously unreported in coupled PbS QD films.more » We interpret these results in terms of a greatly reduced defect concentration for cation-exchanged QDs that mitigates the influence of trap-assisted recombination. Cation-exchanged QDs have recently been employed in highly efficient and air-stable lead chalcogenide QD devices, and the reduced number of trap states inferred here may lead to improved current collection and higher open circuit voltage.« less

  17. Saline as the Sole Contrast Agent for Successful MRI-guided Epidural Injections

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Deli, Martin, E-mail: martin.deli@web.de; Fritz, Jan, E-mail: jfritz9@jhmi.edu; Mateiescu, Serban, E-mail: mateiescu@microtherapy.de

    Purpose. To assess the performance of sterile saline solution as the sole contrast agent for percutaneous magnetic resonance imaging (MRI)-guided epidural injections at 1.5 T. Methods. A retrospective analysis of two different techniques of MRI-guided epidural injections was performed with either gadolinium-enhanced saline solution or sterile saline solution for documentation of the epidural location of the needle tip. T1-weighted spoiled gradient echo (FLASH) images or T2-weighted single-shot turbo spin echo (HASTE) images visualized the test injectants. Methods were compared by technical success rate, image quality, table time, and rate of complications. Results. 105 MRI-guided epidural injections (12 of 105 withmore » gadolinium-enhanced saline solution and 93 of 105 with sterile saline solution) were performed successfully and without complications. Visualization of sterile saline solution and gadolinium-enhanced saline solution was sufficient, good, or excellent in all 105 interventions. For either test injectant, quantitative image analysis demonstrated comparable high contrast-to-noise ratios of test injectants to adjacent body substances with reliable statistical significance levels (p < 0.001). The mean table time was 22 {+-} 9 min in the gadolinium-enhanced saline solution group and 22 {+-} 8 min in the saline solution group (p = 0.75). Conclusion. Sterile saline is suitable as the sole contrast agent for successful and safe percutaneous MRI-guided epidural drug delivery at 1.5 T.« less

  18. High-performance PbS quantum dot vertical field-effect phototransistor using graphene as a transparent electrode

    NASA Astrophysics Data System (ADS)

    Che, Yongli; Zhang, Yating; Cao, Xiaolong; Song, Xiaoxian; Zhang, Haiting; Cao, Mingxuan; Dai, Haitao; Yang, Junbo; Zhang, Guizhong; Yao, Jianquan

    2016-12-01

    Solution processed photoactive PbS quantum dots (QDs) were used as channel in high-performance near-infrared vertical field-effect phototransistor (VFEpT) where monolayer graphene embedded as transparent electrode. In this vertical architecture, the PbS QD channel was sandwiched and naturally protected between the drain and source electrodes, which made the device ultrashort channel length (110 nm) simply the thickness of the channel layer. The VFEpT exhibited ambipolar operation with high mobilities of μe = 3.5 cm2/V s in n-channel operation and μh = 3.3 cm2/V s in p-channel operation at low operation voltages. By using the photoactive PbS QDs as channel material, the VFEpT exhibited good photoresponse properties with a responsivity of 4.2 × 102 A/W, an external quantum efficiency of 6.4 × 104% and a photodetectivity of 2.1 × 109 Jones at the light irradiance of 36 mW/cm2. Additionally, the VFEpT showed excellent on/off switching with good stability and reproducibility and fast response speed with a short rise time of 12 ms in n-channel operation and 10.6 ms in p-channel operation. These high mobilities, good photoresponse properties and simplistic fabrication of our VFEpTs provided a facile route to the high-performance inorganic photodetectors.

  19. Stochastic Modeling of Soil Salinity

    NASA Astrophysics Data System (ADS)

    Suweis, Samir; Rinaldo, Andrea; van der Zee, Sjoerd E. A. T. M.; Maritan, Amos; Porporato, Amilcare

    2010-05-01

    Large areas of cultivated land worldwide are affected by soil salinity. Estimates report that 10% of arable land in over 100 countries, and nine million km2 are salt affected, especially in arid and semi-arid regions. High salinity causes both ion specific and osmotic stress effects, with important consequences for plant production and quality. Salt accumulation in the root zone may be due to natural factors (primary salinization) or due to irrigation (secondary salinization). Simple (e.g., vertically averaged over the soil depth) coupled soil moisture and salt balance equations have been used in the past. Despite their approximations, these models have the advantage of parsimony, thus allowing a direct analysis of the interplay of the main processes. They also provide the ideal starting point to include external, random hydro-climatic fluctuations in the analysis of long-term salinization trends. We propose a minimalist stochastic model of primary soil salinity, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The long term probability density functions of salt mass and concentration are found by reducing the coupled soil moisture and salt mass balance equation to a stochastic differential equation driven by multiplicative Poisson noise. The novel analytical solutions provide insight on the interplay of the main soil, plant and climate parameters responsible for long-term soil salinization. In fact, soil salinity statistics are obtained as a function of climate, soil and vegetation parameters. These, in turn, can be combined with soil moisture statistics to obtain a full characterization of soil salt concentrations and the ensuing risk of primary salinization. In particular, the solutions show the existence of two quite distinct regimes, the first one where the mean salt mass remains nearly constant with increasing rainfall frequency, and the

  20. Synthetic Conditions for High-Accuracy Size Control of PbS Quantum Dots

    DOE PAGES

    Zhang, Jianbing; Crisp, Ryan W.; Gao, Jianbo; ...

    2015-05-04

    Decreasing the variability in quantum dot (QD) syntheses is desirable for better uniformity of samples for use in QD-based studies and applications. Here we report a highly reproducible linear relationship between the concentration of ligand (in this case oleic acid, OA) and the lowest energy exciton peak position (nm) of the resulting PbS QDs for various hot-injection temperatures. Thus, for a given injection temperature, the size of the PbS QD product is purely controlled by the amount of OA. We used this relationship to study PbS QD solar cells that are fabricated from the same size of PbS QDs butmore » synthesized using four different injection temperatures: 95, 120, 150, and 185 °C. We find that the power conversion efficiency does not depend on injection temperature but that the V oc is higher for QDs synthesized at lower temperatures while the J sc is improved in higher temperature QDs.« less

  1. Synthetic Conditions for High-Accuracy Size Control of PbS Quantum Dots.

    PubMed

    Zhang, Jianbing; Crisp, Ryan W; Gao, Jianbo; Kroupa, Daniel M; Beard, Matthew C; Luther, Joseph M

    2015-05-21

    Decreasing the variability in quantum dot (QD) syntheses is desirable for better uniformity of samples for use in QD-based studies and applications. Here we report a highly reproducible linear relationship between the concentration of ligand (in this case oleic acid, OA) and the lowest energy exciton peak position (nm) of the resulting PbS QDs for various hot-injection temperatures. Thus, for a given injection temperature, the size of the PbS QD product is purely controlled by the amount of OA. We used this relationship to study PbS QD solar cells that are fabricated from the same size of PbS QDs but synthesized using four different injection temperatures: 95, 120, 150, and 185 °C. We find that the power conversion efficiency does not depend on injection temperature but that the V(oc) is higher for QDs synthesized at lower temperatures while the J(sc) is improved in higher temperature QDs.

  2. Stability study of docetaxel solution (0.9%, saline) using Non-PVC and PVC tubes for intravenous administration.

    PubMed

    Park, Kang Hoon; Chung, Dong June

    2015-01-01

    Di-2-ethylhexyl phthalate (DEHP) are added to poly(vinyl chloride)(PVC) infusion tubes as a plasticizer to ensure tube flexibility. In addition to previously reported disadvantages of DEHP, released DEHP molecules from PVC tubes can easily interact with surfactants in anticancer drug solutions (i.e., polysorbate 80 for Taxotere®-Inj) and reduce the solubility of docetaxel in aqueous solution during anticancer drug administration. In this study, we investigated the in vitro stability of docetaxel in a 0.9% saline solution under an intravenous administration condition using a PVC tube (high DEHP content) and non-PVC infused tube. The docetaxel solution circulating through the non-PVC tube had better solution stability than through the PVC tube(high DEHP content).

  3. Long-Term In Vitro Degradation of a High-Strength Brushite Cement in Water, PBS, and Serum Solution

    PubMed Central

    Ajaxon, Ingrid; Öhman, Caroline; Persson, Cecilia

    2015-01-01

    Bone loss and fractures may call for the use of bone substituting materials, such as calcium phosphate cements (CPCs). CPCs can be degradable, and, to determine their limitations in terms of applications, their mechanical as well as chemical properties need to be evaluated over longer periods of time, under physiological conditions. However, there is lack of data on how the in vitro degradation affects high-strength brushite CPCs over longer periods of time, that is, longer than it takes for a bone fracture to heal. This study aimed at evaluating the long-term in vitro degradation properties of a high-strength brushite CPC in three different solutions: water, phosphate buffered saline, and a serum solution. Microcomputed tomography was used to evaluate the degradation nondestructively, complemented with gravimetric analysis. The compressive strength, chemical composition, and microstructure were also evaluated. Major changes from 10 weeks onwards were seen, in terms of formation of a porous outer layer of octacalcium phosphate on the specimens with a concomitant change in phase composition, increased porosity, decrease in object volume, and mechanical properties. This study illustrates the importance of long-term evaluation of similar cement compositions to be able to predict the material's physical changes over a relevant time frame. PMID:26587540

  4. Solutions Network Formulation Report. Integrating Salinity Measurements from Aquarius into the Harmful Algal Blooms Observing System

    NASA Technical Reports Server (NTRS)

    Anderson, Daniel; Lewis, David; Hilbert, Kent

    2007-01-01

    This Candidate Solution suggests the use of Aquarius sea surface salinity measurements to improve the NOAA/NCDDC (National Oceanic and Atmospheric Administration s National Coastal Data Development Center) HABSOS (Harmful Algal Blooms Observing System) DST (decision support tool) by enhancing development and movement forecasts of HAB events as well as potential species identification. In the proposed configuration, recurring salinity measurements from the Aquarius mission would augment HABSOS sea surface temperature and in situ ocean current measurements. Thermohaline circulation observations combined with in situ measurements increase the precision of HAB event movement forecasting. These forecasts allow coastal managers and public health officials to make more accurate and timely warnings to the public and to better direct science teams to event sites for collection and further measurements.

  5. ABA and PBS: The Dangers in Creating Artificial Dichotomies in Behavioral Intervention

    ERIC Educational Resources Information Center

    Weiss, Mary Jane; DelPizzo-Cheng, Eliza; LaRue, Robert H.; Sloman, Kimberly

    2009-01-01

    In recent years, there has been a great deal of controversy regarding the definition and independence of Positive Behavioral Supports (PBS) within the context of behavioral intervention. Specifically, behavior analysts have argued over whether PBS is subsumed within Applied Behavior Analysis (ABA) or whether it can be considered a separate…

  6. Synthesis and Characterization of Quantum Dots: A Case Study Using PbS

    ERIC Educational Resources Information Center

    Pan, Yi; Li, Yue Ru; Zhao, Yu; Akins, Daniel L.

    2015-01-01

    A research project for senior undergraduates of chemistry has been developed to introduce syntheses of a series of monodispersed semiconductor PbS quantum dots (QDs) and their characterization methodologies. In this paper, we report the preparation of monodispersed semiconductor PbS QDs with sizes smaller than the exciton Bohr radius using a…

  7. Program on Resorbable Radio Devices

    DTIC Science & Technology

    2014-05-05

    radio circuit - + PDMS Copper Mg PBS Buffer 1© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim wileyonlinelibrary.com Transient, Biocompatible...way, ZnO provides an alternative to silicon [ 16 ] or organic semi- conductors [ 17–20 ] for physically transient forms of electronics and sensors...immersion in several different types of solutions, such as phosphate buffer saline (PBS, pH 4.0, Sigma- Figure 1 . Materials and designs for

  8. Groundwater-saline lakes interaction - The contribution of saline groundwater circulation to solute budget of saline lakes: a lesson from the Dead Sea

    NASA Astrophysics Data System (ADS)

    Kiro, Yael; Weinstein, Yishai; Starinsky, Abraham; Yechieli, Yoseph

    2013-04-01

    Saline lakes act as base level for both surface water and groundwater. Thus, a change in lake levels is expected to result in changes in the hydrogeological system in its vicinity, exhibited in groundwater levels, location of the fresh-saline water interface, sub-lacustrine groundwater discharge (SGD) and saline water circulation. All these processes were observed in the declining Dead Sea system, whose water level dropped by ~35 meters in the last 50 years. This work focuses mainly on the effect of circulation of Dead Sea water in the aquifer, which continues even in this very rapid base level drop. In general, seawater circulation in coastal aquifers is now recognized as a major process affecting trace element mass balances in coastal areas. Estimates of submarine groundwater discharge (SGD) vary over several orders of magnitude (1-1000000 m3/yr per meter shoreline). These estimates are sensitive to fresh-saline SGD ratios and to the temporal and spatial scales of the circulation. The Dead Sea system is an excellent natural field lab for studying seawater-groundwater interaction and large-scale circulation due to the absence of tides and to the minor role played by waves. During Dead Sea water circulation in the aquifer several geochemical reactions occur, ranging from short-term adsorption-desorption reactions and up to long-term precipitation and dissolution reactions. These processes affect the trace element distribution in the saline groundwater. Barite and celestine, which are supersaturated in the lake water, precipitate during circulation in the aquifer, reducing barium (from 5 to 1.5 mg/L), strontium (from 350 to 300 mg/L) and the long-lived 226Ra (from 145 to 60 dpm/L) in the saline groundwater. Redox-controlled reactions cause a decrease in uranium from 2.4 to 0.1 μg/L, and an increase in iron from 1 to 13 mg/L. 228Ra (t1/2=5.75 yr) activity in the Dead Sea is ~1 dpm/L and increase gradually as the saline water flows further inland until reaching

  9. Modeling the effects of different irrigation water salinity on soil water movement, uptake and multicomponent solute transport

    NASA Astrophysics Data System (ADS)

    Lekakis, E. H.; Antonopoulos, V. Z.

    2015-11-01

    Simulation models can be important tools for analyzing and managing irrigation, soil salinization or crop production problems. In this study a mathematical model that describes the water movement and mass transport of individual ions (Ca2+, Mg2+ and Na+) and overall soil salinity by means of the soil solution electrical conductivity, is used. The mass transport equations of Ca2+, Mg2+ and Na+ have been incorporated as part of the integrated model WANISIM and the soil salinity was computed as the sum of individual ions. The model was calibrated and validated against field data, collected during a three year experiment in plots of maize, irrigated with three different irrigation water qualities, at Thessaloniki area in Northern Greece. The model was also used to evaluate salinization and sodification hazards by the use of irrigation water with increasing electrical conductivity of 0.8, 3.2 and 6.4 dS m-1, while maintaining a ratio of Ca2+:Mg2+:Na+ equal to 3:3:2. The qualitative and quantitative procedures for results evaluation showed that there was good agreement between the simulated and measured values of the water content, overall salinity and the concentration of individual soluble cations, at two soil layers (0-35 and 35-75 cm). Nutrient uptake was also taken into account. Locally available irrigation water (ECiw = 0.8 dS m-1) did not cause soil salinization or sodification. On the other hand, irrigation water with ECiw equal to 3.2 and 6.4 dS m-1 caused severe soil salinization, but not sodification. The rainfall water during the winter seasons was not sufficient to leach salts below the soil profile of 110 cm. The modified version of model WANISIM is able to predict the effects of irrigation with saline waters on soil and plant growth and it is suitable for irrigation management in areas with scarce and low quality water resources.

  10. Formulation and synthesis of hydrogels having lower critical solution temperature near body temperature

    NASA Astrophysics Data System (ADS)

    Abidin, A. Z.; Graha, H. P. R.; Trirahayu, D. A.

    2017-07-01

    Copolymerization between bacterial cellulose nanocrystal (CN) and methyl cellulose (MC) was carried out using UV light to produce a biocompatible hydrogel at body temperature and liquid at room temperature. Viscosity and salt effect of the MC and copolymer solution at room temperature and its Lower Critical Solution Temperature (LCST) were evaluated. The analysis showed that the higher concentration of methyl cellulose and salt content in the solution produced lower LCST and higher solution viscosity. All samples of polymer solution with MC concentrations of 1 and 2% have a viscosity less than 5000 cP at room temperature. The solutions with MC concentration of 1, 2, and 3% have respectively LCST of 59, 58, and 57°C, while its copolymer solutions with CN concentration of 0.1, 0.3, and 0.5% have respectively LCST of 55, 51, and 41°C. The salt addition to the solution of MC-CN copolymer with concentrations of 1x and 1.5x Phosphat Buffered Saline (PBS) produces respectively LCST of 47 and 38°C. The results suggest that the copolymer solution of MC-CN could produce a lower LCST and the addition of salt could amplify the effect of LCST decrease that can be used to produce a biocompatible hydrogel with LCST as close as body temperature.

  11. Inorganic-ligand exchanging time effect in PbS quantum dot solar cell

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Byung-Sung; Hong, John; Hou, Bo

    2016-08-08

    We investigate time-dependent inorganic ligand exchanging effect and photovoltaic performance of lead sulfide (PbS) nanocrystal films. With optimal processing time, volume shrinkage induced by residual oleic acid of the PbS colloidal quantum dot (CQD) was minimized and a crack-free film was obtained with improved flatness. Furthermore, sufficient surface passivation significantly increased the packing density by replacing from long oleic acid to a short iodide molecule. It thus facilities exciton dissociation via enhanced charge carrier transport in PbS CQD films, resulting in the improved power conversion efficiency from 3.39% to 6.62%. We also found that excess iodine ions on the PbSmore » surface rather hinder high photovoltaic performance of the CQD solar cell.« less

  12. Bulk Moisture and Salinity Sensor

    NASA Technical Reports Server (NTRS)

    Nurge, Mark; Monje, Oscar; Prenger, Jessica; Catechis, John

    2013-01-01

    Measurement and feedback control of nutrient solutions in plant root zones is critical to the development of healthy plants in both terrestrial and reduced-gravity environments. In addition to the water content, the amount of fertilizer in the nutrient solution is important to plant health. This typically requires a separate set of sensors to accomplish. A combination bulk moisture and salinity sensor has been designed, built, and tested with different nutrient solutions in several substrates. The substrates include glass beads, a clay-like substrate, and a nutrient-enriched substrate with the presence of plant roots. By measuring two key parameters, the sensor is able to monitor both the volumetric water content and salinity of the nutrient solution in bulk media. Many commercially available moisture sensors are point sensors, making localized measurements over a small volume at the point of insertion. Consequently, they are more prone to suffer from interferences with air bubbles, contact area of media, and root growth. This makes it difficult to get an accurate representation of true moisture content and distribution in the bulk media. Additionally, a network of point sensors is required, increasing the cabling, data acquisition, and calibration requirements. measure the dielectric properties of a material in the annular space of the vessel. Because the pore water in the media often has high salinity, a method to measure the media moisture content and salinity simultaneously was devised. Characterization of the frequency response for capacitance and conductance across the electrodes was completed for 2-mm glass bead media, 1- to 2-mm Turface (a clay like media), and 1- to 2-mm fertilized Turface with the presence of root mass. These measurements were then used to find empirical relationships among capacitance (C), the dissipation factor (D), the volumetric water content, and the pore water salinity.

  13. Heterojunction PbS nanocrystal solar cells with oxide charge-transport layers.

    PubMed

    Hyun, Byung-Ryool; Choi, Joshua J; Seyler, Kyle L; Hanrath, Tobias; Wise, Frank W

    2013-12-23

    Oxides are commonly employed as electron-transport layers in optoelectronic devices based on semiconductor nanocrystals, but are relatively rare as hole-transport layers. We report studies of NiO hole-transport layers in PbS nanocrystal photovoltaic structures. Transient fluorescence experiments are used to verify the relevant energy levels for hole transfer. On the basis of these results, planar heterojunction devices with ZnO as the photoanode and NiO as the photocathode were fabricated and characterized. Solution-processed devices were used to systematically study the dependence on nanocrystal size and achieve conversion efficiency as high as 2.5%. Optical modeling indicates that optimum performance should be obtained with thinner oxide layers than can be produced reliably by solution casting. Room-temperature sputtering allows deposition of oxide layers as thin as 10 nm, which enables optimization of device performance with respect to the thickness of the charge-transport layers. The best devices achieve an open-circuit voltage of 0.72 V and efficiency of 5.3% while eliminating most organic material from the structure and being compatible with tandem structures.

  14. Millisecond-Timescale Monitoring of PbS Nanoparticle Nucleation and Growth Using Droplet-Based Microfluidics.

    PubMed

    Lignos, Ioannis; Stavrakis, Stavros; Kilaj, Ardita; deMello, Andrew J

    2015-08-26

    The early-time kinetics (<1 s) of lead sulfide (PbS) quantum dot formation are probed using a novel droplet-based microfluidic platform, which allows for high-throughput and real-time optical analysis of the reactive process with millisecond time resolution. The reaction platform enables the concurrent investigation of the emission characteristics of PbS quantum dots and a real-time estimation of their size and concentration during nucleation and growth. These investigations reveal a two-stage mechanism for PbS nanoparticle formation. The first stage corresponds to the fast conversion of precursor species to PbS crystals, followed by the growth of the formed particles. The growth kinetics of the PbS nanoparticles follow the Lifshitz-Slyozov-Wagner model for Ostwald ripening, allowing direct estimation of the rate constants for the process. In addition, the extraction of absorption spectra of ultrasmall quantum dots is demonstrated for first time in an online manner. The droplet-based microfluidic platform integrated with online spectroscopic analysis provides a new tool for the quantitative extraction of high temperature kinetics for systems with rapid nucleation and growth stages. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Optical, electrical, and photovoltaic properties of PbS thin films by anionic and cationic dopants

    NASA Astrophysics Data System (ADS)

    Cheraghizade, Mohsen; Jamali-Sheini, Farid; Yousefi, Ramin

    2017-06-01

    Lead sulfide (PbS) thin films were deposited by CVD method to examine the effects of anionic and cationic dopants on optical and electrical properties for photovoltaic applications. XRD diffractograms verified the formation of cubic phase of multicrystalline PbS thin films. FESEM images showed surface morphologies in nano-dimensions (rods and flowers). UV-Vis-NIR spectrum revealed absorbance in the visible and NIR regions for all samples, in which dopants decreased the intensity of absorbance. Se as an anionic dopant for PbS thin films increased electrical resistance, acceptor concentrations, and crystallite defects, and decreased flat-band voltage and depletion width. Finally, photovoltaic measurements indicated that Zn-doped PbS thin film, as a photovoltaic cell, exhibited higher conversion efficiency and external quantum efficiency (EQE).

  16. Synovitis induced by joint lavage with hypertonic saline solutions in healthy dairy calves

    PubMed Central

    Achard, Damien; Francoz, David; Desrochers, André; Girard, Christiane; Piché, Caroline

    2012-01-01

    The objective of this study was to evaluate the effect of a single joint lavage with 7.2% or 15% hypertonic saline solutions (HSS) on the tarsocrural joints of healthy calves. The tarsi of 10 calves were randomly lavaged with 7.2% HSS, 15% HSS, or isotonic saline. Synovial fluid samples were collected aseptically on days 1 (before joint lavage), 2, 3, 4, and 8 for complete cytological analysis. Lameness, joint swelling, and pain were recorded daily. Calves were euthanized on day 8 for gross and histological analyses of synovial membranes and articular cartilage. Synovitis was evaluated using a scoring system reflecting inflammatory changes in synovial membranes. Joints irrigated with HSS were more distended and painful compared with isotonic control joints. Swelling decreased consistently in the joints lavaged with 7.2% HSS, whereas it remained unchanged in joints lavaged with 15% HSS. Slight to moderate lameness was observed in the joints lavaged with 15% HSS. In comparison to isotonic saline joints, total protein concentration was significantly increased on day 2 and 3 for the joints lavaged with 7.2% HSS (P ≤ 0.01) and on days 2, 3, and 4 in the joints lavaged with 15% HSS (P ≤ 0.0006). Gross and histological findings revealed that synovitis was more severe in the joints lavaged with 15% HSS but variable in the joints lavaged with 7.2% HSS. No significant differences were observed for the articular cartilage. Fifteen percent HSS is not recommended for joint lavage. Although irrigation with 7.2% HSS may induce a variable synovitis, it was found appropriate for joint lavage. Its effects on septic joints remain undetermined. PMID:23024450

  17. Hydrogeologic processes in saline systems: Playas, sabkhas, and saline lakes

    USGS Publications Warehouse

    Yechieli, Y.; Wood, W.W.

    2002-01-01

    Pans, playas, sabkhas, salinas, saline lakes, and salt flats are hydrologically similar, varying only in their boundary conditions. Thus, in evaluating geochemical processes in these systems, a generic water and solute mass-balance approach can be utilized. A conceptual model of a coastal sabkha near the Arabian Gulf is used as an example to illustrate the various water and solute fluxes. Analysis of this model suggests that upward flux of ground water from underlying formations could be a major source of solutes in the sabkha, but contribute only a small volume of the water. Local rainfall is the main source of water in the modeled sabkha system with a surprisingly large recharge-to-rainfall ratio of more than 50%. The contribution of seawater to the solute budget depends on the ratio of the width of the supratidal zone to the total width and is generally confined to a narrow zone near the shoreline of a typical coastal sabkha. Because of a short residence time of water, steady-state flow is expected within a short time (50,000 years). The solute composition of the brine in a closed saline system depends largely on the original composition of the input water. The high total ion content in the brine limits the efficiency of water-rock interaction and absorption. Because most natural systems are hydrologically open, the chemistry of the brines and the associated evaporite deposits may be significantly different than that predicted for hydrologically closed systems. Seasonal changes in temperature of the unsaturated zone cause precipitation of minerals in saline systems undergoing evaporation. Thus, during the hot dry season months, minerals exhibit retrograde solubility so that gypsum, anhydrite and calcite precipitate. Evaporation near the surface is also a major process that causes mineral precipitation in the upper portion of the unsaturated zone (e.g. halite and carnallite), provided that the relative humidity of the atmosphere is less than the activity of water

  18. 77 FR 40358 - Federal Management Regulation; FMR Bulletin PBS-2012-03; Redesignations of Federal Buildings...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-09

    ... Management Regulation; FMR Bulletin PBS-2012-03; Redesignations of Federal Buildings: Correction AGENCY: Public Buildings Service (PBS), General Services Administration (GSA). ACTION: Notice of a bulletin..., 2012, a bulletin announcing the designation and redesignation of three Federal buildings. Inadvertently...

  19. Investigations in Marine Chemistry: Salinity II.

    ERIC Educational Resources Information Center

    Schlenker, Richard M.

    Presented is a science activity in which the student investigates methods of calibration of a simple conductivity meter via a hands-on inquiry technique. Conductivity is mathematically compared to salinity using a point slope formula and graphical techniques. Sample solutions of unknown salinity are provided so that the students can sharpen their…

  20. Intravenous hypertonic saline solution (7.5%) and oral electrolytes to treat of calves with noninfectious diarrhea and metabolic acidosis.

    PubMed

    Leal, M L R; Fialho, S S; Cyrillo, F C; Bertagnon, H G; Ortolani, E L; Benesi, F J

    2012-01-01

    The aim of this study was to compare the efficacy of treating osmotic diarrhea and dehydration in calves with hypertonic saline solution (HSS) IV, isotonic electrolyte solution (IES) PO, and a combination of these 2 solutions (HSS + IES). Eighteen male calves 8-30 days of age were used to evaluate the efficacy of 3 methods of fluid therapy after induction of osmotic diarrhea and dehydration. The diarrhea and dehydration were induced by administration of saccharose, spironolactone, and hydrochlorothiazide for 48 hours. The animals were randomly divided into 3 experimental groups: Group 1: 7.2% hypertonic saline solution-HSS (5 mL/kg IV); Group 2: oral isotonic electrolyte solution IES (60 mL/kg PO); or Group 3: HSS+IES. Clinical signs and laboratory finding observed 48 hours post-induction (Time 0) included diarrhea, dehydration, lethargy, and metabolic acidosis. Calves treated with HSS + IES experienced decreases in hematocrit, total protein concentration, albumin concentration, urea nitrogen concentration, and plasma volume as well as increases in blood pH, blood bicarbonate concentration, and central venous pressure between 1 and 3 hours post-treatment. These findings also were observed in animals treated with IES, however, at a slower rate than in the HSS + IES-treated animals. Animals treated with HSS continued to display signs of dehydration, lethargy, and metabolic acidosis 24 hours post-treatment. Treatment with a combination of HSS and IES produced rapid and sustainable correction of hypovolemia and metabolic acidosis in calves with noninfections diarrhea and dehydration. Copyright © 2012 by the American College of Veterinary Internal Medicine.

  1. Salinity index determination of porous materials using open-ended probes

    NASA Astrophysics Data System (ADS)

    Szypłowska, Agnieszka; Kafarski, Marcin; Wilczek, Andrzej; Lewandowski, Arkadiusz; Skierucha, Wojciech

    2017-01-01

    The relations among soil water content, bulk electrical conductivity and electrical conductivity of soil solution can be described by a number of theoretical and empirical models. The aim of the paper is to examine the performance of open-ended coaxial probes with and without a short antenna in determination of complex dielectric permittivity spectra, moisture and salinity of porous materials using the salinity index approach. Glass beads of 0.26 and 1.24 mm average diameters moistened to various water contents with distilled water and KCl solutions were used to model the soil material. Due to the larger sensitivity zone, only the probe with the antenna enabled determination of bulk electrical conductivity and salinity index of the samples. The relations between bulk electrical conductivity and dielectric permittivity of the samples were highly linear, which was consistent with the salinity index model. The slope of the relation between salinity index and electrical conductivity of moistening solutions closely matched the value for 100 % sand presented in literature.

  2. Combination of short-length TiO2 nanorod arrays and compact PbS quantum-dot thin films for efficient solid-state quantum-dot-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Zhengguo; Shi, Chengwu; Chen, Junjun; Xiao, Guannan; Li, Long

    2017-07-01

    Considering the balance of the hole diffusion length and the loading quantity of quantum-dots, the rutile TiO2 nanorod array with the length of 600 nm, the diameter of 20 nm, and the areal density of 500 μm-2 is successfully prepared by the hydrothermal method using the aqueous grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 °C for 105 min. The compact PbS quantum-dot thin film on the TiO2 nanorod array is firstly obtained by the spin-coating-assisted successive ionic layer absorption and reaction with using 1,2-ethanedithiol (EDT). The result reveals that the strong interaction between lead and EDT is very important to control the crystallite size of PbS quantum-dots and obtain the compact PbS quantum-dot thin film on the TiO2 nanorod array. The all solid-state sensitized solar cell with the combination of the short-length, high-density TiO2 nanorod array and the compact PbS quantum-dot thin film achieves the photoelectric conversion efficiency of 4.10%, along with an open-circuit voltage of 0.52 V, a short-circuit photocurrent density of 13.56 mA cm-2 and a fill factor of 0.58.

  3. The Applied Behavior Analytic Heritage of PBS: A Dynamic Model of Action-Oriented Research

    ERIC Educational Resources Information Center

    Dunlap, Glen; Horner, Robert H., Ed.

    2006-01-01

    In the past two decades, positive behavior support (PBS) has emerged from applied behavior analysis (ABA) as a newly fashioned approach to problems of behavioral adaptation. ABA was established in the 1960s as a science in which learning principles are systematically applied to produce socially important changes in behavior, whereas PBS was…

  4. Broadband infrared light emitting waveguides based on UV curable PbS quantum dot composites

    NASA Astrophysics Data System (ADS)

    Shen, Kai; Baig, Sarfaraz; Jiang, Guomin; Paik, Young-hun; Kim, Sung Jin; Wang, Michael R.

    2018-02-01

    We present herein the active PbS-photopolymer waveguide fabricated by vacuum assisted microfluidic (VAM) soft lithography technique. The PbS Quantum Dots (QDs) were synthesized using colloidal chemistry methods with tunable sizes and emission wavelengths, resulting in efficient light emission around 1000 nm center wavelength. The PbS QDs have demonstrated much better solubility in our newly synthesized UV curable polymer than SU-8 photoresist, verified by Photoluminescence (PL) testing. Through refractive index control, the PbS QDs-polymer core material and polymer cladding material can efficiently confine the infrared emitting light with a broad spectral bandwidth of 180 nm. Both single-mode and multi-mode light emitting waveguides have been realized.

  5. Preparing ultrafine PbS powders from the scrap lead-acid battery by sulfurization and inert gas condensation

    NASA Astrophysics Data System (ADS)

    Xia, Huipeng; Zhan, Lu; Xie, Bing

    2017-02-01

    A novel method for preparing ultrafine PbS powders involving sulfurization combined with inert gas condensation is developed in this paper, which is applicable to recycle Pb from lead paste of spent lead-acid batteries. Initially, the effects of the evaporation and condensation temperature, the inert gas pressure, the condensation distance and substrate on the morphology of as-obtained PbS ultrafine particles are intensively investigated using sulfur powders and lead particles as reagents. Highly dispersed and homogeneous PbS nanoparticles can be prepared under the optimized conditions which are 1223 K heating temperature, 573 K condensation temperature, 100 Pa inert gas pressure and 60 cm condensation distance. Furthermore, this method is successfully applied to recycle Pb from the lead paste of spent lead acid battery to prepare PbS ultrafine powders. This work does not only provide the theoretical fundamental for PbS preparation, but also provides a novel and efficient method for recycling spent lead-acid battery with high added-value products.

  6. Sequence characterization and spatiotemporal expression patterns of PbS26-RNase gene in Chinese White Pear (Pyrus bretschneideri).

    PubMed

    Zhang, Lin; Jia, Baoguang; Zou, Feng; Tan, Xiaofeng; Liu, Min; Song, Zhibo; Zeng, Yanling; Jiang, Nan; Yuan, Deyi

    2014-01-01

    Many flowering plants exhibit an important intraspecific reproductive barrier phenomenon, that is, self-incompatibility (SI), in which S-RNase genes play a significant role. To clarify the specific function of S-RNase genes in Chinese pears, the full length cDNA of PbS 26 -RNase was isolated by rapid amplification of cDNA ends (RACE) technology from Chinese white pear (Pyrus bretschneideri) cultivar "Hongpisu." The cDNA sequence for PbS 26 -RNase was deposited in GenBank under accession number EU081888. At the amino acid level, the PbS 26 -RNase displayed the highest similarity (96.9%) with PcSa-RNase of P. communis, and only seven amino acid differences were present in the two S-RNases. Phylogenetic analysis of rosaceous S-RNases indicated that the PbS 26 -RNase clustered with maloideous S-RNases, forming a subfamily-specific not a species-specific group. The PbS 26 -RNase gene was specifically expressed in the style but not other tissues/organs. The expression level of the PbS 26 -RNase gene rapidly increased at bell balloon stage (BBS), and then it dropped after pollination. However, the abundance of the PbS 26 -RNase gene transcript in the style was greater after cross-pollination than after self-pollination. In addition, a method for rapidly detecting the PbS 26 -RNase gene was developed via allele-specific primers design. The present study could provide a scientific basis for fully clarifying the mechanism of pear SI at the molecular level.

  7. Sequence Characterization and Spatiotemporal Expression Patterns of PbS 26 -RNase Gene in Chinese White Pear (Pyrus bretschneideri)

    PubMed Central

    Jia, Baoguang; Liu, Min; Song, Zhibo; Zeng, Yanling; Jiang, Nan; Yuan, Deyi

    2014-01-01

    Many flowering plants exhibit an important intraspecific reproductive barrier phenomenon, that is, self-incompatibility (SI), in which S-RNase genes play a significant role. To clarify the specific function of S-RNase genes in Chinese pears, the full length cDNA of PbS 26 -RNase was isolated by rapid amplification of cDNA ends (RACE) technology from Chinese white pear (Pyrus bretschneideri) cultivar “Hongpisu.” The cDNA sequence for PbS 26 -RNase was deposited in GenBank under accession number EU081888. At the amino acid level, the PbS 26 -RNase displayed the highest similarity (96.9%) with PcSa-RNase of P. communis, and only seven amino acid differences were present in the two S-RNases. Phylogenetic analysis of rosaceous S-RNases indicated that the PbS 26 -RNase clustered with maloideous S-RNases, forming a subfamily-specific not a species-specific group. The PbS 26 -RNase gene was specifically expressed in the style but not other tissues/organs. The expression level of the PbS 26 -RNase gene rapidly increased at bell balloon stage (BBS), and then it dropped after pollination. However, the abundance of the PbS 26 -RNase gene transcript in the style was greater after cross-pollination than after self-pollination. In addition, a method for rapidly detecting the PbS 26 -RNase gene was developed via allele-specific primers design. The present study could provide a scientific basis for fully clarifying the mechanism of pear SI at the molecular level. PMID:24737959

  8. Polymer tensiometers in a saline environment.

    NASA Astrophysics Data System (ADS)

    van der Ploeg, Martine; Gooren, H. P. A.; Bakker, G.; Russell, W.; Hoogendam, C. W.; Huiskes, C.; Shouse, P.; de Rooij, G. H.

    2010-05-01

    It is estimated that 20% of all cultivated land and nearly half of the irrigated land is salt-affected, which pose major economic and environmental problems. Salinity may be the result of two processes; dryland and irrigation salinity. Dryland salinity is caused by a rise in the groundwater table, which occurs as a result of the replacement of deep-rooted, perennial native vegetation by shallow-rooted annual species meant for production. Irrigation salinity may occur as a result of poor water quality, poor drainage, or inefficient use of water. Consequently, new strategies to enhance crop yield stability on saline soils represent a major research priority (Botella et al. 2005). At the same time, native vegetation is capable of thriving under saline and/or dry conditions. The plant physiology of such vegetation has been investigated thoroughly, but the relation with in situ soil properties (soil moisture and salinity) may be more difficult to unravel as soil moisture sensors are less sensitive in dry soil, and the signal of most soil moisture content sensors is strongly attenuated by soil salinity. Recently, polymer tensiometer were developed that are able to measure matric potentials (closely related to a soil's moisture status) in dry soils. Polymer tensiometers consist of a solid ceramic, a stainless steel cup and a pressure transducer. The ceramic consist of a support layer and a membrane with 2 nm pore-size to prevent polymer leakage. Between the ceramic membrane and the pressure transducer a tiny chamber is located, which contains the polymer solution. The polymer's osmotic potential strongly reduces the total water potential inside the polymer tensiometer, which causes build-up of osmotic pressure. Polymer tensiometers would thus be an ideal instrument to measure in dry soil, if the polymer inside the tensiometer is not affected by the salts in the soil solution. We will address some key issues regarding the use of POTs in saline environments by showing

  9. Sodium hydroxide based non-detergent decellularizing solution for rat lung.

    PubMed

    Sengyoku, Hideyori; Tsuchiya, Tomoshi; Obata, Tomohiro; Doi, Ryoichiro; Hashimoto, Yasumasa; Ishii, Mitsutoshi; Sakai, Hiromi; Matsuo, Naoto; Taniguchi, Daisuke; Suematsu, Takashi; Lawn, Murray; Matsumoto, Keitaro; Miyazaki, Takuro; Nagayasu, Takeshi

    2018-06-11

    Lung transplantation is the last option for the treatment of end stage chronic lung disorders. Because the shortage of donor lung organs represents the main hurdle, lung regeneration has been considered to overcome this hurdle. Recellularization of decellularized organ scaffold is a promising option for organ regeneration. Although detergents are ordinarily used for decellularization, other approaches are possible. Here we used high alkaline (pH12) sodium hydroxide (NaOH)-PBS solution without detergents for lung decellularization and compared the efficacy on DNA elimination and ECM preservation with detergent based decellularization solutions CHAPS and SDS. Immunohistochemical image analysis showed that cell components were removed by NaOH solution as well as other detergents. A Collagen and GAG assay showed that the collagen reduction of the NaOH group was comparable to that of the CHAPS and SDS groups. However, DNA reduction was more significant in the NaOH group than in other groups (p < 0.0001). The recellularization of HUVEC revealed cell attachment was not inferior to that of the SDS group. Ex vivo functional analysis showed 100% oxygen ventilation increased oxygen partial pressure as artificial hemoglobin vesicle-PBS solution passed through regenerated lungs in the SDS or NaOH group. It was concluded that the NaOH-PBS based decellularization solution was comparable to ordinal decellularizaton solutions and competitive in cost effectiveness and residues in the decellularized scaffold negligible, thus providing another potential option to detergent for future clinical usage.

  10. Removal of Soluble Strontium via Incorporation into Biogenic Carbonate Minerals by Halophilic Bacterium Bacillus sp. Strain TK2d in a Highly Saline Solution

    PubMed Central

    Dotsuta, Yuma; Nakano, Yuriko; Ochiai, Asumi; Utsunomiya, Satoshi; Ohnuki, Toshihiko

    2017-01-01

    ABSTRACT Radioactive strontium (90Sr) leaked into saline environments, including the ocean, from the Fukushima Daiichi Nuclear Power Plant after a nuclear accident. Since the removal of 90Sr using general adsorbents (e.g., zeolite) is not efficient at high salinity, a suitable alternative immobilization method is necessary. Therefore, we incorporated soluble Sr into biogenic carbonate minerals generated by urease-producing microorganisms from a saline solution. An isolate, Bacillus sp. strain TK2d, from marine sediment removed >99% of Sr after contact for 4 days in a saline solution (1.0 × 10−3 mol liter−1 of Sr, 10% marine broth, and 3% [wt/vol] NaCl). Transmission electron microscopy and energy-dispersive X-ray spectroscopy showed that Sr and Ca accumulated as phosphate minerals inside the cells and adsorbed at the cell surface at 2 days of cultivation, and then carbonate minerals containing Sr and Ca developed outside the cells after 2 days. Energy-dispersive spectroscopy revealed that Sr, but not Mg, was present in the carbonate minerals even after 8 days. X-ray absorption fine-structure analyses showed that a portion of the soluble Sr changed its chemical state to strontianite (SrCO3) in biogenic carbonate minerals. These results indicated that soluble Sr was selectively solidified into biogenic carbonate minerals by the TK2d strain in highly saline environments. IMPORTANCE Radioactive nuclides (134Cs, 137Cs, and 90Sr) leaked into saline environments, including the ocean, from the Fukushima Daiichi Nuclear Power Plant accident. Since the removal of 90Sr using general adsorbents, such as zeolite, is not efficient at high salinity, a suitable alternative immobilization method is necessary. Utilizing the known concept that radioactive 90Sr is incorporated into bones by biomineralization, we got the idea of removing 90Sr via incorporation into biominerals. In this study, we revealed the ability of the isolated ureolytic bacterium to remove Sr under high-salinity

  11. Efficacy of disinfecting solutions in removing biofilms from polyvinyl chloride tracheostomy tubes.

    PubMed

    Silva, Rodrigo C; Carver, Ryan A; Ojano-Dirain, Carolyn P; Antonelli, Patrick J

    2013-01-01

    Bacterial biofilms are prevalent in pediatric tracheostomy tubes (TTs) and are not completely cleared by standard cleaning with gauze and household detergents. We aimed to examine the effectiveness of different disinfecting solutions to remove Staphylococcus aureus (SA) and Pseudomonas aerginosa (PA) biofilms from TTs. Prospective, controlled, in vitro microbiologic study. Uniform coupons obtained from polyvinyl chloride (PVC) pediatric TTs were briefly exposed to human plasma. The samples were incubated in growth media with either PA or SA for 7 days, and total bacterial growth was monitored by media turbidity. Five sets of 18 coupons each were exposed for 5 minutes to one of five different solutions: 2% aqueous chlorhexidine gluconate solution, 0.3% aqueous sodium hypochlorite, Polident denture cleanser, 3% hydrogen peroxide, or preservative-free phosphate-buffered saline (PBS) as a negative control. Biofilm presence was measured with bacterial counts, and surface integrity was assessed with scanning electron microscopy (SEM). All treatments significantly reduced mean SA counts (P = <.001). Sodium hypochlorite and chlorhexidine were more effective than peroxide and Polident. Chlorhexidine, sodium hypochlorite, and peroxide reduced PA counts (P = .001, .001, and .002, respectively), but Polident tabs had no significant effect. SEM revealed preserved TT surface integrity after exposure to all solutions. Disinfection with sodium hypochlorite or chlorhexidine solutions significantly reduces SA and PA biofilms on PVC TTs. Standard home care of reusable pediatric TTs may be improved by use of these readily available solutions. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

  12. Genetic diversity analysis of tree peony germplasm using iPBS markers.

    PubMed

    Duan, Y B; Guo, D L; Guo, L L; Wei, D F; Hou, X G

    2015-07-06

    We examined the genetic diversity of 10 wild species (populations) and 55 varieties of tree peony using inter-primer binding site (iPBS) markers. From a total of 36 iPBS primers, 16 were selected based on polymorphic amplification. The number of bands amplified by each primer ranged from 9 to 19, with an average of 12.88 bands per primer. The length of bands ranged from 100 to 2000 bp, concentrated at 200 to 1800 bp. Sixteen primers amplified 206 bands in total, of which 173 bands were polymorphic with a polymorphism ratio of 83.98%. Each primer amplified 10.81 polymorphic bands on average. The data were then used to construct a phylogenetic tree using unweighted pair group method with arithmetic mean methods. Clustering analysis showed that the genetic relationships among the varieties were not only related to the genetic background or geographic origin, but also to the flowering phase, flower color, and flower type. Our data also indicated that iPBS markers were useful tools for classifying tree peony germplasms and for tree peony breeding, and the specific bands were helpful for molecular identification of tree peony varieties.

  13. Isolation of a gene (pbsC) required for siderophore biosynthesis in fluorescent Pseudomonas sp. strain M114.

    PubMed

    Adams, C; Dowling, D N; O'Sullivan, D J; O'Gara, F

    1994-06-03

    An iron-regulated gene, pbsC, required for siderophore production in fluorescent Pseudomonas sp. strain M114 has been identified. A kanamycin-resistance cassette was inserted at specific restriction sites within a 7 kb genomic fragment of M114 DNA and by marker exchange two siderophore-negative mutants, designated M1 and M2, were isolated. The nucleotide sequence of approximately 4 kb of the region flanking the insertion sites was determined and a large open reading frame (ORF) extending for 2409 bp was identified. This gene was designated pbsC (pseudobactin synthesis C) and its putative protein product termed PbsC. PbsC was found to be homologous to a family of enzymes involved in the biosynthesis of secondary metabolites, including EntF of Escherichia coli. These enzymes are believed to act via ATP-dependent binding of AMP to their substrate. Several areas of high sequence homology between these proteins and PbsC were observed, including a conserved AMP-binding domain. The expression of pbsC is iron-regulated as revealed when a DNA fragment containing the upstream region was cloned in a promoter probe vector and conjugated into the wild-type strain, M114. The nucleotide sequence upstream of the putative translational start site contains a region homologous to previously defined -16 to -25 sequences of iron-regulated genes but did not contain an iron-box consensus sequence. It was noted that inactivation of the pbsC gene also affected other iron-regulated phenotypes of Pseudomonas M114.

  14. Chitosan adsorption on nanofibrillated cellulose with different aldehyde content and interaction with phosphate buffered saline.

    PubMed

    Ondaral, Sedat; Çelik, Elif; Kurtuluş, Orçun Çağlar; Aşıkuzun, Elif; Yakın, İsmail

    2018-04-15

    The chitosan adsorption on films prepared using nanofibrillated cellulose (NFC) with different content of aldehyde group was studied by means of Quartz Crystal Microbalance with Dissipation (QCM-D). Results showed that frequency change (Δf) was higher when the chitosan adsorbed on NFC film consisting more aldehyde group indicating the higher adsorption. The (Δf) and dissipation (ΔD) factors completely changed during adsorption of chitosan pre-treated with acetic acid: Δf increased and ΔD decreased, oppositely to un-treated chitosan adsorption. After acid treatment, molecular weight and crystallinity index of chitosan decreased addition to change in chemical structure. It was found that more phosphate buffered saline (PBS), as a model liquid for wound exudate, adsorbed to acid treated chitosan-NFC film, especially to film having more aldehyde groups. Comparing with bare NFC film, chitosan-NFC films adsorbed less PBS because chitosan crosslinked the NFC network and blocked the functional groups of NFC and thus, preventing swelling film. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Do catheter washouts extend patency time in long-term indwelling urethral catheters? A randomized controlled trial of acidic washout solution, normal saline washout, or standard care.

    PubMed

    Moore, Katherine N; Hunter, Kathleen F; McGinnis, Rosemary; Bacsu, Chasta; Fader, Mandy; Gray, Mikel; Getliffe, Kathy; Chobanuk, Janice; Puttagunta, Lakshmi; Voaklander, Donald C

    2009-01-01

    Blockage of long-term indwelling catheters with mineral deposit is an ongoing management issue, but evidence on optimal management is lacking. Our purpose was to examine whether catheter washouts prevent or reduce catheter blockage. A multisite randomized controlled trial. Adults with long-term indwelling catheters that required changing every 3 weeks or less, living in the community, and requiring supportive or continuing care were recruited. Participants were randomly assigned to 1 of 3 groups: control (usual care, no washout), saline washout, or commercially available acidic washout solution (Contisol Maelor Pharmaceuticals Ltd, Wrexham, UK). At baseline visit, the catheter was changed and participants were followed weekly for 8 weeks, with checks for catheter patency and urine pH. Participants randomized to saline or commercial solution had a weekly washout with the appropriate solution. Endpoints were 8 weeks (completion data), 3 or more catheter changes in the 8-week period, or symptomatic urinary tract infection (UTI) requiring antibiotics. The study hypothesis was that catheter life would be extended by 25% in the commercial solution group. It was not possible to blind participants or research nurses to washout versus no intervention, but participants in the saline and washout solution groups were blinded to solution type. One hundred twelve potential participants were screened; 73 were enrolled, randomized, and included in the final analysis. Of these, 53 completed the full 8 weeks of data collection; 16 terminated early because of 3 catheter changes or self-reported 'UTI'. Other reasons for termination were hematuria, latex sensitivity, deceased/severe illness, or personal choice. Analysis of variance was used to analyze mean differences on demographic variables and mean number of weeks in study. Kaplan-Meier survival curve analysis showed no statistical difference between the groups in time to first catheter change. At this time, the evidence is

  16. Biochar-manure compost in conjunction with pyroligneous solution alleviated salt stress and improved leaf bioactivity of maize in a saline soil from central China: a 2-year field experiment.

    PubMed

    Lashari, Muhammad Siddique; Ye, Yingxin; Ji, Haishi; Li, Lianqing; Kibue, Grace Wanjiru; Lu, Haifei; Zheng, Jufeng; Pan, Genxing

    2015-04-01

    Salinity is a major stress threatening crop production in dry lands. A 2-year field experiment was conducted to assess the potential of a biochar product to alleviate salt-stress to a maize crop in a saline soil. The soil was amended with a compost at 12 t ha(-1) of wheat straw biochar and poultry manure compost (BPC), and a diluted pyroligneous solution (PS) at 0.15 t ha(-1) (BPC-PS). Changes in soil salinity and plant performance, leaf bioactivity were examined in the first (BPC-PS1) and second (BPC-PS2) year following a single amendment. While soil salinity significantly decreased, there were large increases in leaf area index, plant performance, and maize grain yield, with a considerable decrease in leaf electrolyte leakage when grown in amendments. Maize leaf sap nitrogen, phosphorus and potassium increased while sodium and chloride decreased, leaf bioactivity related to osmotic stress was significantly improved following the treatments. These effects were generally greater in the second than in the first year. A combined amendment of crop straw biochar with manure compost plus pyroligneous solution could help combat salinity stress to maize and improve productivity in saline croplands in arid/semi-arid regions threatened increasingly by global climate change. © 2014 Society of Chemical Industry.

  17. The application of crystal soaking technique to study the effect of zinc and cresol on insulinotropin crystals grown from a saline solution.

    PubMed

    Kim, Y; Haren, A M

    1995-11-01

    The purpose of this study is to investigate the effect of zinc and cresol on the structure of insulinotropin crystals. Insulinotropin crystals grown from a saline solution were treated with zinc and/or m-cresol using a crystal soaking technique. The effects of these additives on the crystal structure were investigated with powder X-ray diffraction, photomicrography, and differential scanning calorimetry. The molecular interaction between insulinotropin and m-trifluorocresol in solution was also studied by 19F NMR: The data suggest that the original crystals grown from a saline solution have relatively weak lattice forces. After the addition of m-cresol to the suspension of the insulinotropin crystals, the crystals were immediately rendered amorphous. The m-cresol molecules which diffused into the crystals through solvent channels may have disturbed the lattice interactions that maintain the integrity of the crystal. In contrast, the zinc added to the suspension stabilized the crystal lattice so that the subsequent addition of m-cresol did not alter the integrity of the crystals. A marked increase in melting point (206 degrees versus 184 degrees) and heat of fusion (24.6 J/g versus 1.4 J/g) of the crystals was observed after the treatment with zinc. The solubility of the zinc treated crystals in a pH 7.1 phosphate buffered saline was 1/20 of that of the original crystals. When the insulinotropin crystals were treated with the additives using a crystal soaking method, the crystals underwent structural changes. Zinc stabilized the crystal lattice, and reduced the solubility of the peptide.

  18. Tunneling effect on double potential barriers GaAs and PbS

    NASA Astrophysics Data System (ADS)

    Prastowo, S. H. B.; Supriadi, B.; Ridlo, Z. R.; Prihandono, T.

    2018-04-01

    A simple model of transport phenomenon tunnelling effect through double barrier structure was developed. In this research we concentrate on the variation of electron energy which entering double potential barriers to transmission coefficient. The barriers using semiconductor materials GaAs (Galium Arsenide) with band-gap energy 1.424 eV, distance of lattice 0.565 nm, and PbS (Lead Sulphide) with band gap energy 0.41 eV distance of lattice is 18 nm. The Analysisof tunnelling effect on double potentials GaAs and PbS using Schrodinger’s equation, continuity, and matrix propagation to get transmission coefficient. The maximum energy of electron that we use is 1.0 eV, and observable from 0.0025 eV- 1.0 eV. The shows the highest transmission coefficient is0.9982 from electron energy 0.5123eV means electron can pass the barriers with probability 99.82%. Semiconductor from materials GaAs and PbS is one of selected material to design semiconductor device because of transmission coefficient directly proportional to bias the voltage of semiconductor device. Application of the theoretical analysis of resonant tunnelling effect on double barriers was used to design and develop new structure and combination of materials for semiconductor device (diode, transistor, and integrated circuit).

  19. B1-B2 phase transition mechanism and pathway of PbS under pressure

    NASA Astrophysics Data System (ADS)

    Adeleke, Adebayo A.; Yao, Yansun

    2018-03-01

    Experimental studies at finite Pressure-Temperature (P-T) conditions and a theoretical study at 0 K of the phase transition in lead sulphide (PbS) have been inconclusive. Many studies that have been done to understand structural transformation in PbS can broadly be classified into two main ideological streams—one with Pnma and another with Cmcm orthorhombic intermediate phase. To foster better understanding of this phenomenon, we present the result of the first-principles study of phase transition in PbS at finite temperature. We employed the particle swarm-intelligence optimization algorithm for the 0 K structure search and first-principles metadynamics simulations to study the phase transition pathway of PbS from the ambient pressure, 0 K Fm-3m structure to the high-pressure Pm-3m phase under experimentally achievable P-T conditions. Significantly, our calculation shows that both streams are achievable under specific P-T conditions. We further uncover new tetragonal and monoclinic structures of PbS with space group P21/c and I41/amd, respectively. We propose the P21/c and I41/amd as a precursor phase to the Pnma and Cmcm phases, respectively. We investigated the stability of the new structures and found them to be dynamically stable at their stability pressure range. Electronic structure calculations reveal that both P21/c and I41/amd phases are semiconducting with direct and indirect bandgap energies of 0.69(5) eV and 0.97(3) eV, respectively. In general, both P21/c and I41/amd phases were found to be energetically competitive with their respective orthorhombic successors.

  20. Deposition of Cu-doped PbS thin films with low resistivity using DC sputtering

    NASA Astrophysics Data System (ADS)

    Soetedjo, Hariyadi; Siswanto, Bambang; Aziz, Ihwanul; Sudjatmoko

    2018-03-01

    Investigation of the electrical resistivity of Cu-doped PbS thin films has been carried out. The films were prepared using a DC sputtering technique. The doping was achieved by introducing the Cu dopant plate material directly on the surface of the PbS sputtering target plate. SEM-EDX data shows the Cu concentration in the PbS film to be proportional to the Cu plate diameter. The XRD pattern indicates the film is in crystalline cubic form. The Hall effect measurement shows that Cu doping yields an increase in the carrier concentration to 3.55 × 1019 cm-3 and a significant decrease in electrical resistivity. The lowest resistivity obtained was 0.13 Ωcm for a Cu concentration of 18.5%. Preferential orientation of (1 1 1) and (2 0 0) occurs during deposition.

  1. Salinity Gradients for Sustainable Energy: Primer, Progress, and Prospects.

    PubMed

    Yip, Ngai Yin; Brogioli, Doriano; Hamelers, Hubertus V M; Nijmeijer, Kitty

    2016-11-15

    Combining two solutions of different composition releases the Gibbs free energy of mixing. By using engineered processes to control the mixing, chemical energy stored in salinity gradients can be harnessed for useful work. In this critical review, we present an overview of the current progress in salinity gradient power generation, discuss the prospects and challenges of the foremost technologies - pressure retarded osmosis (PRO), reverse electrodialysis (RED), and capacitive mixing (CapMix) and provide perspectives on the outlook of salinity gradient power generation. Momentous strides have been made in technical development of salinity gradient technologies and field demonstrations with natural and anthropogenic salinity gradients (for example, seawater-river water and desalination brine-wastewater, respectively), but fouling persists to be a pivotal operational challenge that can significantly ebb away cost-competitiveness. Natural hypersaline sources (e.g., hypersaline lakes and salt domes) can achieve greater concentration difference and, thus, offer opportunities to overcome some of the limitations inherent to seawater-river water. Technological advances needed to fully exploit the larger salinity gradients are identified. While seawater desalination brine is a seemingly attractive high salinity anthropogenic stream that is otherwise wasted, actual feasibility hinges on the appropriate pairing with a suitable low salinity stream. Engineered solutions are foulant-free and can be thermally regenerative for application in low-temperature heat utilization. Alternatively, PRO, RED, and CapMix can be coupled with their analog separation process (reverse osmosis, electrodialysis, and capacitive deionization, respectively) in salinity gradient flow batteries for energy storage in chemical potential of the engineered solutions. Rigorous techno-economic assessments can more clearly identify the prospects of low-grade heat conversion and large-scale energy storage

  2. Effect of lead ion concentration on the structural and optical properties of nano-crystalline PbS thin films

    NASA Astrophysics Data System (ADS)

    Zaman, S.; Mehmood, S. K.; Mansoor, M.; Asim, M. M.

    2014-06-01

    PbS thin films have received considerable attention because of their potential applications in opto-electronics applications. Spontaneous reaction of lead acetate and thiourea in aqueous hydrazine hydrate has been used for depositing PbS thin films on glass substrates. Structural and optical properties of PbS thin films are greatly influenced by the morality of the reactants and crystal defects in the lattice. Our work focuses on the variation in lead ion concentration and its effect on the structural and optical properties of PbS thin films. The deposited films were analyzed using XRD, SEM, spectrophotometer and dark resistance measurement. XRD patterns indicated the formation of major phase of nano crystalline PbS with minor presence of lead oxide phase. We also noticed that peak intensity ratio of I111/I200 varied by changing the Pb ion concentration. The film thickness and dark resistance increased whereas optical band gap decreased with the decreasing Pb ion concentration. SEM scans showed that the grain size is less than 100 nm and is not affected by varying Pb ion concentration.

  3. PiHOG1, a stress regulator MAP kinase from the root endophyte fungus Piriformospora indica, confers salinity stress tolerance in rice plants

    PubMed Central

    Jogawat, Abhimanyu; Vadassery, Jyothilakshmi; Verma, Nidhi; Oelmüller, Ralf; Dua, Meenakshi; Nevo, Eviatar; Johri, Atul Kumar

    2016-01-01

    In this study, yeast HOG1 homologue from the root endophyte Piriformospora indica (PiHOG1) was isolated and functionally characterized. Functional expression of PiHOG1 in S. cerevisiae ∆hog1 mutant restored osmotolerance under high osmotic stress. Knockdown (KD) transformants of PiHOG1 generated by RNA interference in P. indica showed that genes for the HOG pathway, osmoresponse and salinity tolerance were less stimulated in KD-PiHOG1 compared to the wild-type under salinity stress. Furthermore, KD lines are impaired in the colonization of rice roots under salinity stress of 200 mM NaCl, and the biomass of the host plants, their shoot and root lengths, root number, photosynthetic pigment and proline contents were reduced as compared to rice plants colonized by WT P. indica. Therefore, PiHOG1 is critical for root colonisation, salinity tolerance and the performance of the host plant under salinity stress. Moreover, downregulation of PiHOG1 resulted not only in reduced and delayed phosphorylation of the remaining PiHOG1 protein in colonized salinity-stressed rice roots, but also in the downregulation of the upstream MAP kinase genes PiPBS2 and PiSSK2 involved in salinity tolerance signalling in the fungus. Our data demonstrate that PiHOG1 is not only involved in the salinity response of P. indica, but also helping host plant to overcome salinity stress. PMID:27849025

  4. Salinization and Saline Environments

    NASA Astrophysics Data System (ADS)

    Vengosh, A.

    2003-12-01

    One of the most conspicuous phenomena of water-quality degradation, particularly in arid and semi-arid zones, is salinization of water and soil resources. Salinization is a long-term phenomenon, and during the last century many aquifers and river basins have become unsuitable for human consumption owing to high levels of salinity. Future exploitation of thousands of wells in the Middle East and in many other water-scarce regions in the world depends, to a large extent, on the degree and rate of salinization. Moreover, every year a large fraction of agricultural land is salinized and becomes unusable.Salinization is a global environmental phenomenon that affects many different aspects of our life (Williams, 2001a, b): changing the chemical composition of natural water resources (lakes, rivers, and groundwater), degrading the quality of water supply to the domestic and agriculture sectors, contribution to loss of biodiversity, taxonomic replacement by halotolerant species ( Williams, 2001a, b), loss of fertile soil, collapse of agricultural and fishery industries, changing of local climatic conditions, and creating severe health problems (e.g., the Aral Basin). The damage due to salinity in the Colorado River Basin alone, for example, ranges between 500 and 750 million per year and could exceed 1 billion per year if the salinity in the Imperial Dam increases from 700 mg L-1 to 900 mg L-1 (Bureau of Reclamation, 2003, USA). In Australia, accelerating soil salinization has become a massive environmental and economic disaster. Western Australia is "losing an area equal to one football oval an hour" due to spreading salinity ( Murphy, 1999). The annual cost for dryland salinity in Australia is estimated as AU700 million for lost land and AU$130 million for lost production ( Williams et al., 2002). In short, the salinization process has become pervasive.Salinity in water is usually defined by the chloride content (mg L-1) or total dissolved solids content (TDS, mg L-1or g

  5. A photodiode based on PbS nanocrystallites for FYTRONIX solar panel automatic tracking controller

    NASA Astrophysics Data System (ADS)

    Wageh, S.; Farooq, W. A.; Tataroğlu, A.; Dere, A.; Al-Sehemi, Abdullah G.; Al-Ghamdi, Ahmed A.; Yakuphanoglu, F.

    2017-12-01

    The structural, optical and photoelectrical properties of the fabricated Al/PbS/p-Si/Al photodiode based on PbS nanocrystallites were investigated. The PbS nanocrystallites were characterized by X-ray diffraction (XRD), UV-VIS-NIR, Infrared and Raman spectroscopy. The XRD diffraction peaks show that the prepared PbS nanostructure is in high crystalline state. Various electrical parameters of the prepared photodiode were analyzed from the electrical characteristics based on I-V and C-V-G. The photodiode has a high rectification ratio of 5.85×104 at dark and ±4 V. Moreover, The photocurrent results indicate a strong photovoltaic behavior. The frequency dependence of capacitance and conductance characteristics was attributed to depletion region behavior of the photodiode. The diode was used to control solar panel power automatic tracking controller in dual axis. The fabricated photodiode works as a photosensor to control Solar tracking systems.

  6. Incomplete turgor adjustment in Cladophora rupestrisunder fluctuating salinity regimes

    NASA Astrophysics Data System (ADS)

    Wiencke, Christian; Gorham, John; Tomos, Deri; Davenport, John

    1992-04-01

    Turgor pressure fluctuates strongly in Cladophora rupestrissubjected to low salinities and shows only a small tendency to readjust to the normal value in full seawater (incomplete turgor adjustment). This was revealed by direct turgor pressure measurements and by chemical analyses of osmotic solutes after exposure of upper and lower shore Cladophorato the different salinity regimes occurring in the intertidal zone or representing steady state osmotic acclimation. The main internal osmotic solutes were K +, Cl -, amino acids, NO 3-and glycine betaine. Na +, SO 42-and PO 43-were of less importance. The sum of the charges on the cations was similar to that for the anions. K +, Cl -and, to a lesser extent, amino acids were responsible for limited turgor pressure adjustment which did occur. The concentrations of the major osmotic solutes were influenced not only by salinity but also by light: those of amino acids and NO 3-were increased while those of K +and Cl -were decreased under illumination. Cladophorapopulations from the upper and lower shore differed in their ability to restore internal K +and Cl -levels on transfer to full seawater after long term exposure to low salinity. This may indicate ecotypic variation.

  7. WE-E-BRB-02: Implementation of Pencil Beam Scanning (PBS) Proton Therapy Treatment for Liver Patient

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lin, L.

    Strategies for treating thoracic and liver tumors using pencil beam scanning proton therapy Thoracic and liver tumors have not been treated with pencil beam scanning (PBS) proton therapy until recently. This is because of concerns about the significant interplay effects between proton spot scanning and patient’s respiratory motion. However, not all tumors have unacceptable magnitude of motion for PBS proton therapy. Therefore it is important to analyze the motion and understand the significance of the interplay effect for each patient. The factors that affect interplay effect and its washout include magnitude of motion, spot size, spot scanning sequence and speed.more » Selection of beam angle, scanning direction, repainting and fractionation can all reduce the interplay effect. An overview of respiratory motion management in PBS proton therapy including assessment of tumor motion and WET evaluation will be first presented. As thoracic tumors have very different motion patterns from liver tumors, examples would be provided for both anatomic sites. As thoracic tumors are typically located within highly heterogeneous environments, dose calculation accuracy is a concern for both treatment target and surrounding organs such as spinal cord or esophagus. Strategies for mitigating the interplay effect in PBS will be presented and the pros and cons of various motion mitigation strategies will be discussed. Learning Objectives: Motion analysis for individual patients with respect to interplay effect Interplay effect and mitigation strategies for treating thoracic/liver tumors with PBS Treatment planning margins for PBS The impact of proton dose calculation engines over heterogeneous treatment target and surrounding organs I have a current research funding from Varian Medical System under the master agreement between University of Pennsylvania and Varian; L. Lin, I have a current funding from Varian Medical System under the master agreement between University of

  8. WE-E-BRB-03: Implementation of PBS Proton Therapy Treatment for Free Breathing Lung Cancer Patients

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, H.

    Strategies for treating thoracic and liver tumors using pencil beam scanning proton therapy Thoracic and liver tumors have not been treated with pencil beam scanning (PBS) proton therapy until recently. This is because of concerns about the significant interplay effects between proton spot scanning and patient’s respiratory motion. However, not all tumors have unacceptable magnitude of motion for PBS proton therapy. Therefore it is important to analyze the motion and understand the significance of the interplay effect for each patient. The factors that affect interplay effect and its washout include magnitude of motion, spot size, spot scanning sequence and speed.more » Selection of beam angle, scanning direction, repainting and fractionation can all reduce the interplay effect. An overview of respiratory motion management in PBS proton therapy including assessment of tumor motion and WET evaluation will be first presented. As thoracic tumors have very different motion patterns from liver tumors, examples would be provided for both anatomic sites. As thoracic tumors are typically located within highly heterogeneous environments, dose calculation accuracy is a concern for both treatment target and surrounding organs such as spinal cord or esophagus. Strategies for mitigating the interplay effect in PBS will be presented and the pros and cons of various motion mitigation strategies will be discussed. Learning Objectives: Motion analysis for individual patients with respect to interplay effect Interplay effect and mitigation strategies for treating thoracic/liver tumors with PBS Treatment planning margins for PBS The impact of proton dose calculation engines over heterogeneous treatment target and surrounding organs I have a current research funding from Varian Medical System under the master agreement between University of Pennsylvania and Varian; L. Lin, I have a current funding from Varian Medical System under the master agreement between University of

  9. Tolerance of Hordeum marinum accessions to O2 deficiency, salinity and these stresses combined

    PubMed Central

    Malik, Al Imran; English, Jeremy Parker; Colmer, Timothy David

    2009-01-01

    Background and Aims When root-zone O2 deficiency occurs together with salinity, regulation of shoot ion concentrations is compromised even more than under salinity alone. Tolerance was evaluated amongst 34 accessions of Hordeum marinum, a wild species in the Triticeae, to combined salinity and root-zone O2 deficiency. Interest in H. marinum arises from the potential to use it as a donor for abiotic stress tolerance into wheat. Methods Two batches of 17 H. marinum accessions, from (1) the Nordic Gene Bank and (2) the wheat belt of Western Australia, were exposed to 0·2 or 200 mol m−3 NaCl in aerated or stagnant nutrient solution for 28–29 d. Wheat (Triticum aestivum) was included as a sensitive check species. Growth, root porosity, root radial O2 loss (ROL) and leaf ion (Na+, K+, Cl−) concentrations were determined. Key Results Owing to space constraints, this report is focused mainly on the accessions from the Nordic Gene Bank. The 17 accessions varied in tolerance; relative growth rate was reduced by 2–38 % in stagnant solution, by 8–42 % in saline solution (aerated) and by 39–71 % in stagnant plus saline treatment. When in stagnant solution, porosity of adventitious roots was 24–33 %; salinity decreased the root porosity in some accessions, but had no effect in others. Roots grown in stagnant solution formed a barrier to ROL, but variation existed amongst accessions in apparent barrier ‘strength’. Leaf Na+ concentration was 142–692 µmol g−1 d. wt for plants in saline solution (aerated), and only increased to 247–748 µmol g−1 d. wt in the stagnant plus saline treatment. Leaf Cl− also showed only small effects of stagnant plus saline treatment, compared with saline alone. In comparison with H. marinum, wheat was more adversely affected by each stress alone, and particularly when combined; growth reductions were greater, adventitious root porosity was 21 %, it lacked a barrier to ROL, leaf K+ declined to lower levels, and leaf Na+ and

  10. Effect of ionic strength and presence of serum on lipoplexes structure monitorized by FRET

    PubMed Central

    Madeira, Catarina; Loura, Luís MS; Prieto, Manuel; Fedorov, Aleksander; Aires-Barros, M Raquel

    2008-01-01

    Background Serum and high ionic strength solutions constitute important barriers to cationic lipid-mediated intravenous gene transfer. Preparation or incubation of lipoplexes in these media results in alteration of their biophysical properties, generally leading to a decrease in transfection efficiency. Accurate quantification of these changes is of paramount importance for the success of lipoplex-mediated gene transfer in vivo. Results In this work, a novel time-resolved fluorescence resonance energy transfer (FRET) methodology was used to monitor lipoplex structural changes in the presence of phosphate-buffered saline solution (PBS) and fetal bovine serum. 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP)/pDNA lipoplexes, prepared in high and low ionic strength solutions, are compared in terms of complexation efficiency. Lipoplexes prepared in PBS show lower complexation efficiencies when compared to lipoplexes prepared in low ionic strength buffer followed by addition of PBS. Moreover, when serum is added to the referred formulation no significant effect on the complexation efficiency was observed. In physiological saline solutions and serum, a multilamellar arrangement of the lipoplexes is maintained, with reduced spacing distances between the FRET probes, relative to those in low ionic strength medium. Conclusion The time-resolved FRET methodology described in this work allowed us to monitor stability and characterize quantitatively the structural changes (variations in interchromophore spacing distances and complexation efficiencies) undergone by DOTAP/DNA complexes in high ionic strength solutions and in presence of serum, as well as to determine the minimum amount of potentially cytotoxic cationic lipid necessary for complete coverage of DNA. This constitutes essential information regarding thoughtful design of future in vivo applications. PMID:18302788

  11. An Attempt to Shorten Loading Time of Epirubicin into DC Beads® Using Vibration and a Sieve.

    PubMed

    Sonoda, Akinaga; Nitta, Norihisa; Yamamoto, Takefumi; Tomozawa, Yuki; Ohta, Shinichi; Watanabe, Shobu; Murata, Kiyoshi

    2017-04-01

    We investigated the possibility of shortening the time required for loading epirubicin into calibrated polyvinyl alcohol-based hydrogel beads (DC Beads ® ) to be used for transarterial chemoembolization. After separating the beads suspended in phosphate-buffered saline (PBS) solution by the use of a sieve (clearance 75 µm), epirubicin hydrochloride (EH) was loaded for 20, 30, or 60 s under vibration into DC beads. The EH loading rate into conventionally prepared (control) beads, i.e., beads loaded for 30 min without vibration, and vibration-loaded beads were calculated from the residual EH concentration in the bead-depleted EH solution. The amount of EH eluted from conventionally and vibration-loaded samples into a PBS solution (pH 7.0) was measured at 15 and 30 min and 1, 2, 6, 12, and 24 h. We also recorded the inhibitory effect of the PBS solution on the loading time. Using frozen sections, the EH load in the beads was evaluated visually under a fluorescence microscope. Spectrophotometry (495 nm) showed that the loading rate was 98.98 ± 0.34, 99.02 ± 0.32, and 99.50 ± 0.11 % with 20-, 30-, and 60-s vibration, respectively. The eluted rate was statistically similar between vibration- and statically loaded (control) beads. The PBS solution hampered EH loading into the beads. Visually, the distribution of EH in conventionally and vibration-loaded DC beads was similar. The use of vibration and the removal of PBS solution when epirubicin hydrochloride was loaded into DC beads dramatically shortened the loading time of epirubicin hydrochloride into DC beads.

  12. Study of Preschool Parents and Caregivers Use of Technology and PBS KIDS Transmedia Resources: A Report to the CPB-PBS "Ready to Learn Initiative"

    ERIC Educational Resources Information Center

    Pasnik, Shelley; Llorente, Carlin

    2012-01-01

    Leaders of the CPB-PBS "Ready To Learn" Initiative understand the important role parents and caregivers play in ensuring young children's healthy development and academic learning. In order for young children, especially those living in traditionally underserved communities, to succeed at school and thrive outside of the classroom, educational…

  13. [Wavelength Selection in Hemolytic Evaluation Systems with Spectrophotometry Detection].

    PubMed

    Zhang, Hong; Su, Baochang; Ye, Xunda; Luo, Man

    2016-04-01

    Spectrophotometry is a simple hemolytic evaluation method commonly used in new drugs,biomedical materials and blood products.It is for the quantitative analysis of the characteristic absorption peaks of hemoglobin.Therefore,it is essential to select the correct detection wavelength when the evaluation system has influences on the conformation of hemoglobin.Based on the study of changes in the characteristic peaks over time of the hemolysis supernatant in four systems,namely,cell culture medium,phosphate buffered saline(PBS),physiological saline and banked blood preservation solution,using continuous wavelength scanning,the selections of detection wavelength were proposed as follows.In the cell culture medium system,the wavelength of 415 nm should be selected within 4h;,near 408 nm should be selected within 4~72h.In PBS system,within 4h,541 nm,577nm or 415 nm should be selected;4~72h,541 nm,577nm or near 406 nm should be selected.In physiological saline system,within 4h,414 nm should be selected;4~72h,near 405 nm should be selected;within 12 h,541nm or 577 nm could also be selected.In banked blood preservation solution system,within 72 h,415nm,540 nm or 576 nm should be selected.

  14. "Ready To Learn" Transmedia Demonstration Station Study: A Report to the CPB-PBS "Ready to Learn Initiative"

    ERIC Educational Resources Information Center

    Pasnik, Shelley; Llorente, Carlin

    2012-01-01

    The 2012 Transmedia Demonstration Stations program study is part of the multiyear CPB-PBS "Ready To Learn" summative evaluation initiative by Education Development Center, Inc., (EDC) and SRI International (SRI). Through a series of related studies, the authors are documenting, and, whenever possible, measuring the impact of PBS KIDS…

  15. Spin-coating deposition of PbS and CdS thin films for solar cell application

    NASA Astrophysics Data System (ADS)

    Patel, Jayesh; Mighri, Frej; Ajji, Abdellah; Tiwari, Devendra; Chaudhuri, Tapas K.

    2014-12-01

    In this work, we describe a simple spin-coating deposition technique for lead sulphide (PbS) and cadmium sulphide (CdS) films from a methanolic metal-thiourea complex. The characterization of the films by X-ray diffraction and X-ray photoelectron spectroscopy techniques revealed that pure cubic phase PbS and CdS layers were formed via this method. As shown by atomic force microscopy and scanning electron microscopy results, both films were homogeneous and presented a smooth surface. Optical properties showed that the energy band gap of PbS and CdS films were around 1.65 and 2.5 eV, respectively. The PbS film is p-type in nature with an electrical conductivity of around 0.8 S/cm. The hole concentration and mobility were 2.35 × 1018 cm-3 and 2.16 × 10-3 cm2/V/s, respectively, as determined from Hall measurement. Both films were used to develop a thin film solar cell device of graphite/PbS/CdS/ITO/glass. Device characterization showed the power conversion efficiency of around 0.24 %. The corresponding open circuit voltage, short circuit current and fill factor were 0.570 V, 1.32 mA/cm2 and 0.32, respectively.

  16. Diluted povidone-iodine versus saline for dressing metal-skin interfaces in external fixation.

    PubMed

    Chan, C K; Saw, A; Kwan, M K; Karina, R

    2009-04-01

    To compare infection rates associated with 2 dressing solutions for metal-skin interfaces. 60 patients who underwent distraction osteogenesis with external fixators were equally randomised into 2 dressing solution groups (diluted povidone-iodine vs. saline). Fixations were attained using either rigid stainless steel 5-mm diameter half pins or smooth stainless steel 1.8-mm diameter wires. Half-pin fixation had one metal-skin interface, whereas wire fixation had 2 interfaces. Patients were followed up every 2 weeks for 6 months. Of all 788 metal-skin interfaces, 143 (18%) were infected: 72 (19%) of 371 in the diluted povidone-iodine group and 71 (17%) of 417 in the saline group. Dressing solution and patient age did not significantly affect infection rates. Half-pin fixation was more likely to become infected than wire fixation (25% vs 15%). Saline is as effective as diluted povidone-iodine as a dressing solution for metal-skin interfaces of external fixators. Saline is recommended in view of its easy availability and lower costs.

  17. Corrosion, ion release and Mott-Schottky probe of chromium oxide coatings in saline solution with potential for orthopaedic implant applications

    NASA Astrophysics Data System (ADS)

    Ogwu, A. A.; Oje, A. M.; Kavanagh, J.

    2016-04-01

    We report our investigation on chromium oxide thin film coatings that show a negligible ion release during electrochemical corrosion testing in saline solution. The chemical constituents of the films prepared by reactive magnetron sputtering were identified to be predominantly Cr2O3 based on Raman spectroscopy anti-symmetric stretching vibration modes for CrIII-O and other peaks and an FTIR spectroscopy E u vibrational mode at 409 cm-1. X-ray photoelectron spectroscopy, multiplet fitting for 2P 3/2 and 2P 1/2 states also confirmed the predominantly Cr2O3 stoichiometry in the films. The prepared chromium oxide coatings showed superior pitting corrosion resistance compared to the native chromium oxide films on bare uncoated stainless steel when tested under open circuit potential, potentiodynamic polarisation and cyclic voltammetry in saline solution. The chromium ion released into solution during the corrosion testing of stainless steel substrates coated with chromium oxide coatings was found to be negligibly small based on atomic absorption spectroscopy measurements. Our Mott-Schottky analysis investigation showed that the negligibly small ion release from the chromium oxide coated steel substrates is most likely due to a much lower defect density on the surface of the deposited coatings compared to the native oxide layer on the uncoated steel substrates. This opens up the opportunity for using chromium oxide surface coatings in hip, knee and other orthopaedic implants where possible metal ion release in vivo still poses a great challenge.

  18. Comparison of bend angle measurements in fresh cryopreserved cartilage specimens after electromechanical reshaping

    NASA Astrophysics Data System (ADS)

    Karimi, Koohyar; Protsenko, Dimitry; Wu, Edward C.; Foulad, Allen; Manuel, Cyrus T.; Lim, Amanda; Wong, Brian J. F.

    2010-02-01

    Cryopreservation of cartilage has been investigated for decades and is currently an established protocol. However, the reliability and applicability of cartilage cryopreservation for the use in electromechanical reshaping (EMR) has not been studied exclusively. A system to cryopreserve large numbers of tissue specimens provides a steady source of cartilage of similar quality for experimentation at later dates. This will reduce error that may arise from different cartilage stock, and has the potential to maximize efficiency under time constraints. Our study utilizes a unique methodology to cryopreserve septal cartilage for use in EMR studies. Rabbit septal cartilage specimens were harvested and standardized to 20 x 8 x 1 mm, and placed in one of three solutions (normal saline, PBS, 10% DMSO in PBS) for four hours in a cold storage room at 4 degrees Celsius. Then, each cartilage specimen was vacuumed and sealed in an anti-frost plastic bag and stored in a freezer at -80 degrees Celsius for 1 to 3 weeks duration. EMR was performed using 2 and 6 volts for 2 minutes application time. Bend angle measurements of the cryopreserved cartilage specimens were compared to bend angles of fresh cartilage which underwent EMR using the same parameters. Results demonstrate that normal saline, phosphate buffered saline (PBS), and PBS with DMSO were effective in cryopreservation, and indicated no significant differences in bend angle measurements when compared to no cryopreservation. Our methodology to cryopreserve cartilage specimens provides a successful approach for use in conducting large-scale EMR studies.

  19. Comparison of carrier multiplication yields in PbS and PbSe nanocrystals: the role of competing energy-loss processes.

    PubMed

    Stewart, John T; Padilha, Lazaro A; Qazilbash, M Mumtaz; Pietryga, Jeffrey M; Midgett, Aaron G; Luther, Joseph M; Beard, Matthew C; Nozik, Arthur J; Klimov, Victor I

    2012-02-08

    Infrared band gap semiconductor nanocrystals are promising materials for exploring generation III photovoltaic concepts that rely on carrier multiplication or multiple exciton generation, the process in which a single high-energy photon generates more than one electron-hole pair. In this work, we present measurements of carrier multiplication yields and biexciton lifetimes for a large selection of PbS nanocrystals and compare these results to the well-studied PbSe nanocrystals. The similar bulk properties of PbS and PbSe make this an important comparison for discerning the pertinent properties that determine efficient carrier multiplication. We observe that PbS and PbSe have very similar biexciton lifetimes as a function of confinement energy. Together with the similar bulk properties, this suggests that the rates of multiexciton generation, which is the inverse of Auger recombination, are also similar. The carrier multiplication yields in PbS nanocrystals, however, are strikingly lower than those observed for PbSe nanocrystals. We suggest that this implies the rate of competing processes, such as phonon emission, is higher in PbS nanocrystals than in PbSe nanocrystals. Indeed, our estimations for phonon emission mediated by the polar Fröhlich-type interaction indicate that the corresponding energy-loss rate is approximately twice as large in PbS than in PbSe. © 2011 American Chemical Society

  20. Changes in biomechanical properties of glenohumeral joint capsules with adhesive capsulitis by repeated capsule-preserving hydraulic distensions with saline solution and corticosteroid.

    PubMed

    Koh, Eun S; Chung, Sun G; Kim, Tae Uk; Kim, Hee Chan

    2012-12-01

    To investigate whether capsule-preserving hydraulic distension with saline solution and corticosteroid for adhesive capsulitis induces biomechanical alterations in glenohumeral joint capsules along with clinical improvements. A case series. University outpatient clinic of physical medicine and rehabilitation. Eighteen patients with unilateral adhesive capsulitis. INTERVENTION AND MAIN OUTCOME MEASUREMENTS: Three hydraulic distensions with saline solution and corticosteroid were performed with 1-month intervals. To avoid rupturing capsules, all distensions were monitored by using real-time pressure-volume curves. Stiffness, maximal volume capacity, and pressure at the maximal volume capacity of the capsule were measured at each intervention. Clinical parameters, such as pain and range of motion, were recorded before, 3 days after, and 1 month after each distension. Stiffness decreased (47.6 ± 27.1 mm Hg/mL to 31.7 ± 18.4 mm Hg/mL to 24.2 ± 14.0 mm Hg/mL, mean SD) and maximal volume capacity increased (18.8 ± 7.3 mL to 20.5 ± 7.5 mL to 24.2 ± 7.0 mL, mean SD) significantly (P = .001 for both) at each repeated hydraulic distension. Pressure at the maximal volume capacity tended to decrease, but the decrements were not statistically significant (P = .662). The clinical parameters were significantly improved throughout and 1 month after the 3 repeat procedures (P < .05 for all). Capsule-preserving hydraulic distension changed the biomechanical properties of the glenohumeral joint capsule, lessening the stiffness and enlarging the volume capacity. These alterations were accompanied by improved range of motion and relief of pain. Repeated capsule-preserving hydraulic distension with saline solution and corticosteroid would be useful to treat adhesive capsulitis and to evaluate the treatment results. Copyright © 2012 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  1. Quantifying the degradation of TNT and RDX in a saline environment with and without UV-exposure.

    PubMed

    Sisco, Edward; Najarro, Marcela; Bridge, Candice; Aranda, Roman

    2015-06-01

    Terrorist attacks in a maritime setting, such as the bombing of the USS Cole in 2000, or the detection of underwater mines, require the development of proper protocols to collect and analyse explosive material from a marine environment. In addition to proper analysis of the explosive material, protocols must also consider the exposure of the material to potentially deleterious elements, such as UV light and salinity, time spent in the environment, and time between storage and analysis. To understand how traditional explosives would be affected by such conditions, saline solutions of explosives were exposed to natural and artificial sunlight. Degradation of the explosives over time was then quantified using negative chemical ionization gas chromatography mass spectrometry (GC/NCI-MS). Two explosives, trinitrotoluene (TNT) and cyclotrimethylenetrinitramine (RDX), were exposed to different aqueous environments and light exposures with salinities ranging from freshwater to twice the salinity of ocean water. Solutions were then aged for up to 6 months to simulate different conditions the explosives may be recovered from. Salinity was found to have a negligible impact on the degradation of both RDX and TNT. RDX was stable in solutions of all salinities while TNT solutions degraded regardless of salinity. Solutions of varying salinities were also exposed to UV light, where accelerated degradation was seen for both explosives. Potential degradation products of TNT were identified using electrospray ionization mass spectrometry (ESI-MS), and correspond to proposed degradation products discussed in previously published works [1]. Published by Elsevier Ireland Ltd.

  2. AFM and SFG studies of pHEMA-based hydrogel contact lens surfaces in saline solution: adhesion, friction, and the presence of non-crosslinked polymer chains at the surface.

    PubMed

    Kim, Seong Han; Opdahl, Aric; Marmo, Chris; Somorjai, Gabor A

    2002-04-01

    The surfaces of two types of soft contact lenses neutral and ionic hydrogels--were characterized by atomic force microscopy (AFM) and sum-frequency-generation (SFG) vibrational spectroscopy. AFM measurements in saline solution showed that the presence of ionic functional groups at the surface lowered the friction and adhesion to a hydrophobic polystyrene tip. This was attributed to the specific interactions of water and the molecular orientation of hydrogel chains at the surface. Friction and adhesion behavior also revealed the presence of domains of non-crosslinked polymer chains at the lens surface. SFG showed that the lens surface became partially dehydrated upon exposure to air. On this partially dehydrated lens surface, the non-crosslinked domains exhibited low friction and adhesion in AFM. Fully hydrated in saline solution, the non-crosslinked domains extended more than tens of nanometers into solution and were mobile.

  3. Extracting renewable energy from a salinity difference using a capacitor.

    PubMed

    Brogioli, Doriano

    2009-07-31

    Completely renewable energy can be produced by using water solutions of different salinity, like river water and sea water. Many different methods are already known, but development is still at prototype stage. Here I report a novel method, based on electric double-layer capacitor technology. Two porous electrodes, immersed in the salt solution, constitute a capacitor. It is first charged, then the salt solution is brought into contact with fresh water. The electrostatic energy increases as the salt concentration of the solution is reduced due to diffusion. This device can be used to turn sources of salinity difference into completely renewable sources of energy. An experimental demonstration is given, and performances and possible improvements are discussed.

  4. Luminescence and transient lifetime studies for energy transfer of PbS QD films

    NASA Astrophysics Data System (ADS)

    Wang, Joanna S.; Ullrich, Bruno; Dass, Chandriker K.; Das, Anirban; Wai, Chien M.; Brown, Gail J.; Hendrickson, Joshua R.

    2017-08-01

    Quantum confined semiconductor materials in colloidal form have drawn great attention in scientific communities due to the size-tunability, which controls their optical properties. PbS quantum dots (QDs) are exciting candidates for quantum optics, particularly due to the control of the QD sizes during the synthetic process enabling the realization of precisely tunable emission properties in the near-infrared region. Differently sized pairs of PbS QDs were deposited onto glass substrates to form thin films using supercritical CO2 (sc-CO2) deposition and solvent deposition methods (SDM). The fluorescence and photoluminescence (PL) spectra obtained from these closely packed films prepared by the sc-CO2 method reveal effective Förster resonance energy transfer (FRET) between two different sized dots, while the films composed of three different QD sizes show an even more effective FRET from the smallest to the largest ones. Energy transfer can be observed more directly by temporally resolved PL decay of mixed dots. By means of transient lifetime measurements, a mixed PbS film with 3.1 and 4.7 nm QDs was studied for FRET by time correlated single photon counting. The PL peak of the 3.1 nm QDs is quenched with respect to the emission of the 4.7 nm QDs and decays faster, and the best fit for the lifetime (decay constant)-1 is a biexponential decay mode. The long wavelength decay (4.7 nm QDs) is best fit by a mono-exponential equation. More theoretical and experimental work is required for a thorough understanding of the radiative lifetimes of PbS QDs in mixed QD systems.

  5. Knot Security of 5 Metric (USP 2) Sutures: Influence of Knotting Technique, Suture Material, and Incubation Time for 14 and 28 Days in Phosphate Buffered Saline and Inflamed Equine Peritoneal Fluid.

    PubMed

    Sanders, Ruth E; Kearney, Clodagh M; Buckley, Conor T; Jenner, Florien; Brama, Pieter A

    2015-08-01

    To evaluate knot security for 3 knot types created in 3 commonly used 5 metric suture materials incubated in physiological and pathological fluids. In vitro mechanical study. Knotted suture loops (n = 5/group). Loops of 3 different suture materials (glycolide/lactide copolymer; polyglactin 910; polydioxanone) were created around a 20 mm rod using 3 knot types (square [SQ], surgeon's [SK], and triple knot [TK]) and were tested to failure in distraction (6 mm/min) after tying (day 0) and after being incubated for 14 and 28 days in phosphate buffered saline (PBS) or inflamed peritoneal fluid. Failure load (N) and mode were recorded and compared. For polydioxanone, significant differences in force to knot failure were found between SQ and SK/TK but not between SK and TK. The force required to break all constructs increased after incubation in phosphate buffered saline (PBS). With glycolide/lactide copolymer no differences in force to knot failure were observed. With polyglactin 910, a significant difference between SQ and TK was observed, which was not seen between the other knot types. Incubation in inflamed peritoneal fluid caused a larger and more rapid decrease in force required to cause knot failure than incubation in PBS. Mechanical properties of suture materials have significant effects on knot security. For polydioxanone, SQ is insufficient to create a secure knot. Additional wraps above a SK confer extra stability in some materials, but this increase may not be clinically relevant or justifiable. Glycolide/lactide copolymer had excellent knot security. © Copyright 2015 by The American College of Veterinary Surgeons.

  6. Formation of hydroxyl radical from San Joaquin Valley particles extracted in a cell-free solution

    NASA Astrophysics Data System (ADS)

    Shen, H.; Anastasio, C.

    2011-06-01

    Previous studies have suggested that the adverse health effects from ambient particulate matter (PM) are linked to the formation of reactive oxygen species (ROS) by PM. While hydroxyl radical (•OH) is the most reactive of the ROS species, there are few quantitative studies of •OH generation from PM. Here we report on •OH formation from PM collected at an urban (Fresno) and rural (Westside) site in the San Joaquin Valley (SJV) of California. We quantified •OH in PM extracts using a cell-free, phosphate-buffered saline (PBS) solution with or without 50 μM ascorbate (Asc). The results show that generally the urban Fresno PM generates much more •OH than the rural Westside PM. The presence of Asc at a physiologically relevant concentration in the extraction solution greatly enhances •OH formation from all the samples. Fine PM (PM2.5) generally makes more •OH than the corresponding coarse PM (PMcf, i.e., 2.5 to 10 μm) normalized by air volume collected, while the coarse PM typically generates more •OH normalized by PM mass. •OH production by SJV PM is reduced on average by (97 ± 6) % when the transition metal chelator desferoxamine (DSF) is added to the extraction solution, indicating a dominant role of transition metals. By measuring calibration curves of •OH generation from copper and iron, and quantifying copper and iron concentrations in our particle extracts, we find that PBS-soluble copper is primarily responsible for •OH production by the SJV PM, while iron often makes a significant contribution. Extrapolating our results to expected burdens of PM-derived •OH in human lung lining fluid suggests that typical daily PM exposures in the San Joaquin Valley are unlikely to result in a high amount of pulmonary •OH, although high PM events could produce much higher levels of •OH, which might lead to cytotoxicity.

  7. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sonoda, Akinaga, E-mail: akinagasonoda@yahoo.co.jp; Nitta, Norihisa; Yamamoto, Takefumi

    PurposeWe investigated the possibility of shortening the time required for loading epirubicin into calibrated polyvinyl alcohol-based hydrogel beads (DC Beads{sup ®}) to be used for transarterial chemoembolization.MethodAfter separating the beads suspended in phosphate-buffered saline (PBS) solution by the use of a sieve (clearance 75 µm), epirubicin hydrochloride (EH) was loaded for 20, 30, or 60 s under vibration into DC beads. The EH loading rate into conventionally prepared (control) beads, i.e., beads loaded for 30 min without vibration, and vibration-loaded beads were calculated from the residual EH concentration in the bead-depleted EH solution. The amount of EH eluted from conventionally and vibration-loadedmore » samples into a PBS solution (pH 7.0) was measured at 15 and 30 min and 1, 2, 6, 12, and 24 h. We also recorded the inhibitory effect of the PBS solution on the loading time. Using frozen sections, the EH load in the beads was evaluated visually under a fluorescence microscope.ResultsSpectrophotometry (495 nm) showed that the loading rate was 98.98 ± 0.34, 99.02 ± 0.32, and 99.50 ± 0.11 % with 20-, 30-, and 60-s vibration, respectively. The eluted rate was statistically similar between vibration- and statically loaded (control) beads. The PBS solution hampered EH loading into the beads. Visually, the distribution of EH in conventionally and vibration-loaded DC beads was similar.DiscussionThe use of vibration and the removal of PBS solution when epirubicin hydrochloride was loaded into DC beads dramatically shortened the loading time of epirubicin hydrochloride into DC beads.« less

  8. Controlled release formulation of an anti-depression drug based on a L-phenylalanate-zinc layered hydroxide intercalation compound

    NASA Astrophysics Data System (ADS)

    Hashim, Norhayati; Sharif, Sharifah Norain Mohd; Isa, Illyas Md; Hamid, Shahidah Abdul; Hussein, Mohd Zobir; Bakar, Suriani Abu; Mamat, Mazidah

    2017-06-01

    The intercalation of L-phenylalanate (LP) into the interlayer gallery of zinc layered hydroxide (ZLH) has been successfully executed using a simple direct reaction method. The synthesised intercalation compound, zinc layered hydroxide-L-phenylalanate (ZLH-LP), was characterised using PXRD, FTIR, CHNS, ICP-OES, TGA/DTG, FESEM and TEM. The PXRD patterns of the intercalation compound demonstrate an intense and symmetrical peak, indicating a well-ordered crystalline layered structure. The appearance of an intercalation peak at a low angle of 2θ with a basal spacing of 16.3 Å, signifies the successful intercalation of the L-phenylalanate anion into the interlayer gallery of the host. The intercalation is also validated by FTIR spectroscopy and CHNS elemental analysis. Thermogravimetric analysis confirms that the ZLH-LP intercalation compound has higher thermal stability than the pristine L-phenylalanine. The observed percentage of L-phenylalanate accumulated release varies in each release media, with 84.5%, 79.8%, 63.8% and 61.8% release in phosphate buffer saline (PBS) solution at pH 4.8, deionised water, PBS solution at pH 7.4 and NaCl solution, respectively. The release behaviour of LP from its intercalation compounds in deionised water and PBS solution at pH 4.8 follows pseudo second order, whereas in NaCl solution and PBS solution at pH 7.4, it follows the parabolic diffusion model. This study shows that the synthesised ZLH-LP intercalation compound can be used for the formation of a new generation of materials for targeted drug release with controlled release properties.

  9. iPBS: a universal method for DNA fingerprinting and retrotransposon isolation.

    PubMed

    Kalendar, Ruslan; Antonius, Kristiina; Smýkal, Petr; Schulman, Alan H

    2010-11-01

    Molecular markers are essential in plant and animal breeding and biodiversity applications, in human forensics, and for map-based cloning of genes. The long terminal repeat (LTR) retrotransposons are well suited as molecular markers. As dispersed and ubiquitous transposable elements, their "copy and paste" life cycle of replicative transposition leads to new genome insertions without excision of the original element. Both the overall structure of retrotransposons and the domains responsible for the various phases of their replication are highly conserved in all eukaryotes. Nevertheless, up to a year has been required to develop a retrotransposon marker system in a new species, involving cloning and sequencing steps as well as the development of custom primers. Here, we describe a novel PCR-based method useful both as a marker system in its own right and for the rapid isolation of retrotransposon termini and full-length elements, making it ideal for "orphan crops" and other species with underdeveloped marker systems. The method, iPBS amplification, is based on the virtually universal presence of a tRNA complement as a reverse transcriptase primer binding site (PBS) in LTR retrotransposons. The method differs from earlier retrotransposon isolation methods because it is applicable not only to endogenous retroviruses and retroviruses, but also to both Gypsy and Copia LTR retrotransposons, as well as to non-autonomous LARD and TRIM elements, throughout the plant kingdom and to animals. Furthermore, the inter-PBS amplification technique as such has proved to be a powerful DNA fingerprinting technology without the need for prior sequence knowledge.

  10. Design and development of novel linker for PbS quantum dots/TiO₂ mesoscopic solar cell.

    PubMed

    Etgar, Lioz; Park, Jinhyung; Barolo, Claudia; Nazeeruddin, Md K; Viscardi, Guido; Graetzel, Michael

    2011-09-01

    A novel bifunctional linker molecule, bis(4-mercaptophenyl)phosphinic acid, is designed to be used in a QDs solar cells. The linker anchors to TiO(2) mesoporous film through the phosphinic acid functional group and to the PbS QDs through the two thiol groups. The way of attachment of this new linker molecule in a photovoltaic PbS QDs/TiO(2) mesoporous device was studied by FTIR measurements. The photovoltaic performance of this new linker in a heterojunction PbS QDs solar cell show high V(oc) relative to QDs based solar cells, which will allow to receive high power conversion efficiency using this novel designed linker. This novel bifunctional linker molecule should pave the way for enhancing binding strength, and efficiency of QDs solar cells compared to the state-of-the-art linkers.

  11. The effects of magnetic fields exposure on relative permittivity of saline solutions measured by a high resolution SPR system

    PubMed Central

    Jiang, Li; Zhao, Xinyuan; Fei, Yue; Yu, Dongdong; Qian, Jun; Tong, Jinguang; Chen, Guangdi; He, Sailing

    2016-01-01

    A measurement system for the relative permittivity of a physiological solution under 50 Hz magnetic fields (MF) is presented. It is based on a phase-sensitive surface plasmon resonance (SPR) system. Relative permittivity was analyzed for different solute concentrations of sodium chloride under various MF exposure parameters. We found that MF exposure at 0.2–4.0 mT step-wise decreased significantly the SPR phase signal of a 0.9% sodium chloride solution while 0.1 mT of MF exposure did not. The decreases in the SPR phase signal depended on the duration of MF exposure, and the signal reached a plateau after 15 min of exposure. Interestingly, the decreased SPR phase signal showed a gradual increase and approached the background level when the exposure was drawn off. In addition, we found that the response of the sodium chloride solution to MF also depended on its concentration. In brief, the relative permittivity of sodium chloride in solutions appears to be practically affected by 50 Hz MF exposure. Our data indicates that the relative permittivity of the saline solution influenced by MF exposure should be considered when investigating the biological effects of MF exposure on organisms in experimental study. PMID:27121618

  12. Nonvolatile infrared memory in MoS2/PbS van der Waals heterostructures

    PubMed Central

    Wen, Yao; Cai, Kaiming; Cheng, Ruiqing; Yin, Lei; Zhang, Yu; Li, Jie; Wang, Zhenxing; Wang, Feng; Wang, Fengmei; Shifa, Tofik Ahmed; Jiang, Chao; Yang, Hyunsoo

    2018-01-01

    Optoelectronic devices for information storage and processing are at the heart of optical communication technology due to their significant applications in optical recording and computing. The infrared radiations of 850, 1310, and 1550 nm with low energy dissipation in optical fibers are typical optical communication wavebands. However, optoelectronic devices that could convert and store the infrared data into electrical signals, thereby enabling optical data communications, have not yet been realized. We report an infrared memory device using MoS2/PbS van der Waals heterostructures, in which the infrared pulse intrigues a persistent resistance state that hardly relaxes within our experimental time scales (more than 104 s). The device fully retrieves the memory state even after powering off for 3 hours, indicating its potential for nonvolatile storage devices. Furthermore, the device presents a reconfigurable switch of 2000 stable cycles. Supported by a theoretical model with quantitative analysis, we propose that the optical memory and the electrical erasing phenomenon, respectively, originate from the localization of infrared-induced holes in PbS and gate voltage pulse-enhanced tunneling of electrons from MoS2 to PbS. The demonstrated MoS2 heterostructure–based memory devices open up an exciting field for optoelectronic infrared memory and programmable logic devices. PMID:29770356

  13. Nonvolatile infrared memory in MoS2/PbS van der Waals heterostructures.

    PubMed

    Wang, Qisheng; Wen, Yao; Cai, Kaiming; Cheng, Ruiqing; Yin, Lei; Zhang, Yu; Li, Jie; Wang, Zhenxing; Wang, Feng; Wang, Fengmei; Shifa, Tofik Ahmed; Jiang, Chao; Yang, Hyunsoo; He, Jun

    2018-04-01

    Optoelectronic devices for information storage and processing are at the heart of optical communication technology due to their significant applications in optical recording and computing. The infrared radiations of 850, 1310, and 1550 nm with low energy dissipation in optical fibers are typical optical communication wavebands. However, optoelectronic devices that could convert and store the infrared data into electrical signals, thereby enabling optical data communications, have not yet been realized. We report an infrared memory device using MoS 2 /PbS van der Waals heterostructures, in which the infrared pulse intrigues a persistent resistance state that hardly relaxes within our experimental time scales (more than 10 4 s). The device fully retrieves the memory state even after powering off for 3 hours, indicating its potential for nonvolatile storage devices. Furthermore, the device presents a reconfigurable switch of 2000 stable cycles. Supported by a theoretical model with quantitative analysis, we propose that the optical memory and the electrical erasing phenomenon, respectively, originate from the localization of infrared-induced holes in PbS and gate voltage pulse-enhanced tunneling of electrons from MoS 2 to PbS. The demonstrated MoS 2 heterostructure-based memory devices open up an exciting field for optoelectronic infrared memory and programmable logic devices.

  14. Atomistic understanding of cation exchange in PbS nanocrystals using simulations with pseudoligands

    PubMed Central

    Fan, Zhaochuan; Lin, Li-Chiang; Buijs, Wim; Vlugt, Thijs J. H.; van Huis, Marijn A.

    2016-01-01

    Cation exchange is a powerful tool for the synthesis of nanostructures such as core–shell nanocrystals, however, the underlying mechanism is poorly understood. Interactions of cations with ligands and solvent molecules are systematically ignored in simulations. Here, we introduce the concept of pseudoligands to incorporate cation-ligand-solvent interactions in molecular dynamics. This leads to excellent agreement with experimental data on cation exchange of PbS nanocrystals, whereby Pb ions are partially replaced by Cd ions from solution. The temperature and the ligand-type control the exchange rate and equilibrium composition of cations in the nanocrystal. Our simulations reveal that Pb ions are kicked out by exchanged Cd interstitials and migrate through interstitial sites, aided by local relaxations at core–shell interfaces and point defects. We also predict that high-pressure conditions facilitate strongly enhanced cation exchange reactions at elevated temperatures. Our approach is easily extendable to other semiconductor compounds and to other families of nanocrystals. PMID:27160371

  15. Induced synthesis of toroid-like lead sulfide nanocomposites in ethanol solution through a protein templating route

    NASA Astrophysics Data System (ADS)

    Zhang, Li; Qin, Dezhi; Yang, Guangrui; Du, Xian; Zhang, Qiuxia; Li, Feng

    2015-09-01

    The toroid-like PbS nanocrystals have been prepared in zein ethanol solution based on self-assembly template of protein molecules. From transmission electron microscopy observation, the obtained samples were monodispersed with an average size of about 47 nm. The chemical composition and crystal structure of nanocomposites were determined by X-ray diffraction and energy-dispersive X-ray spectrum measurements. The interaction between PbS and zein was investigated through Fourier transform infrared, photoluminescence, circular dichroism (CD) spectra, and thermogravimetric analysis. The PbS nanocrystals could react with nitrogen and oxygen atoms of zein molecules through coordination and electrostatic force. The CD spectra results suggested that PbS nanocrystals induced the conformational transition of protein from α-helix to β-sheet and then self-assembled into ring or toroid nanostructure. The quenching of zein fluorescence induced by PbS nanocrystals also showed the change in the chemical microenvironments of the fluorescent amino acid residues in the protein structure. The key step of this facile, biomimetic route was the formation of self-assembly nanostructure of zein, which could regulate the nucleation and growth of toroid-like PbS nanocrystals.

  16. Conjunctival and corneal reactions in rabbits following short- and repeated exposure to preservative-free tafluprost, commercially available latanoprost and 0.02% benzalkonium chloride

    PubMed Central

    Liang, H; Baudouin, C; Pauly, A; Brignole-Baudouin, F

    2008-01-01

    Aim: To compare the conjunctival and corneal reactions of commercially available solution of latanoprost (Xalatan) and preservative-free (PF) tafluprost in rabbits. Methods: The rabbits received 50 μl of phosphate-buffered saline (PBS), PF-tafluprost 0.0015%, latanoprost 0.005% or benzalkonium chloride (BAK) 0.02%; all solutions were applied at 5 min intervals for a total of 15 times. The ocular surface toxicity was investigated using slit-lamp biomicroscopy examination, flow cytometry (FCM) and on imprints for CD45 and tumour necrosis factor-receptor 1 (TNFR1) conjunctival impression cytology (CIC) and corneal in vivo confocal microscopy (IVCM). Standard immunohistology also assessed inflammatory/apoptotic cells. Results: Clinical observation and IVCM images showed the highest ocular surface toxicity with latanoprost and BAK, while PF-tafluprost and PBS eyes presented almost normal corneoconjunctival aspects. FCM showed a higher expression of CD45+ and TNFR1+ in latanoprost- or BAK-instilled groups, compared with PF-tafluprost and PBS groups. Latanoprost induced fewer positive cells for inflammatory marker expressions in CIC specimens compared with BAK-alone, both of which were higher than with PF-tafluprost or PBS. Immunohistology showed the same tendency of toxic ranking. Conclusion: The authors confirm that rabbit corneoconjunctival surfaces presented a better tolerance when treated with PF-tafluprost compared with commercially available latanoprost or BAK solution. PMID:18723745

  17. Rheological and Tribological Properties of Complex Biopolymer Solutions

    NASA Astrophysics Data System (ADS)

    Klossner, Rebecca Reese

    2011-12-01

    The rheological and tribological properties of an experimental synovial fluid model were investigated in order to determine the solution dynamics of the three most abundant macromolecules present in synovial fluid, the fluid that lubricates freely moving (synovial) joints. These components, hyaluronic acid (HA) and the plasma proteins, albumin and gamma-globulins are combined in a phosphate buffered saline solution (PBS) and subjected to steady shear rheology testing, as well as nanoindenter-based scratch testing, which allows for the study of the lubrication properties of the experimental synovial fluid model. Steady shear experiments, where the shear rate was increased from low to high, and then decreased from high to low, showed hysteresis in only protein containing solutions, whereas samples of HA in PBS behaved as a "typical" polyelectrolyte in solution. Subsequent rheological experiments on the synovial fluid model exhibited an increase in viscosity at low shear stresses, indicating that a structure was present at these low shear stresses, which was not found at higher shear stresses. This result is in agreement with studies conducted on the same model which show unusual rheological behavior at low shear rates. Low shear stresses can cause modifications to the external protein surface, resulting in their unfolding and creating many opportunities for the molecules to reorder themselves. As the proteins reorder themselves, the newly exposed hydrophobic patches will have a tendency to aggregate together, creating a network within the fluid, and, in turn causing the observed increased viscosity at low shear stresses. Additionally, an anti-inflammatory drug, hydroxychloroquine (HCQ) was added to the solutions. This addition diminishes the protein aggregation process substantially. Finally, the HA component of the synovial fluid model was replaced with a neutral polymer in order to examine the role of HA in synovial fluid. As suspected, the HA appears to have

  18. Hyaluronic acid improves "pleasantness" and tolerability of nebulized hypertonic saline in a cohort of patients with cystic fibrosis.

    PubMed

    Buonpensiero, Paolo; De Gregorio, Fabiola; Sepe, Angela; Di Pasqua, Antonio; Ferri, Pasqualina; Siano, Maria; Terlizzi, Vito; Raia, Valeria

    2010-11-01

    Inhaled hypertonic saline improves lung function and decreases pulmonary exacerbations in people with cystic fibrosis. However, side effects such as cough, narrowing of airways and saltiness cause intolerance of the therapy in 8% of patients. The aim of our study was to compare the effect of an inhaled solution of hyaluronic acid and hypertonic saline with hypertonic solution alone on safety and tolerability. A total of 20 patients with cystic fibrosis aged 6 years and over received a single treatment regimen of 7% hypertonic saline solution or hypertonic solution with 0.1% hyaluronate for 2 days nonconsecutively after a washout period in an open crossover study. Cough, throat irritation, and salty taste were evaluated by a modified ordinal score for assessing tolerability; "pleasantness" was evaluated by a five-level, Likert-type scale. Forced expiratory volume in 1 second was registered before and after the end of the saline inhalations. All 20 patients (nine males, 11 females, mean age 13 years, range 8.9-17.7) completed the study. The inhaled solution of 0.1% hyaluronic acid and hypertonic saline significantly improved tolerability and pleasantness compared to hypertonic saline alone. No major adverse effects were observed. No difference was documented in pulmonary function tests between the two treatments. Hyaluronic acid combined with hypertonic saline solution may contribute to improved adherence to hypertonic saline therapy. Further clinical trials are needed to confirm our findings. Considering the extraordinary versatility of hyaluronic acid in biological reactions, perspective studies could define its applicability to halting progression of lung disease in cystic fibrosis.

  19. Lead(II) Complex Formation with L-cysteine in Aqueous Solution

    PubMed Central

    Jalilehvand, Farideh; Sisombath, Natalie S.; Schell, Adam C.; Facey, Glenn A.

    2015-01-01

    The lead(II) complexes formed with the multidentate chelator L-cysteine (H2Cys) in alkaline aqueous solution were studied using 207Pb, 13C and 1H NMR, Pb LIII-edge X-ray absorption and UV-vis. spectroscopic techniques, complemented by electro-spray ion mass spectrometry (ESI-MS). The H2Cys/Pb(II) mole ratios were varied from 2.1 to 10.0 for two sets of solutions with CPb(II) = 0.01 and 0.1 M, respectively, prepared at pH values (9.1 – 10.4) for which precipitates of Pb(II)-cysteine dissolved. At low H2Cys/Pb(II) mole ratios (2.1 – 3.0) a mixture of the dithiolate [Pb(S,N-Cys)2]2− and [Pb(S,N,O-Cys)(S-HCys)]− complexes with the average Pb-(N/O) and Pb-S distances 2.42 ± 0.04 Å and 2.64 ± 0.04 Å, respectively, was found to dominate. At high concentration of free cysteinate (> 0.7 M) a significant amount converts to the trithiolate [Pb(S,N-Cys)(S-HCys)2]2−, including a minor amount of a PbS3 coordinated [Pb(S-HCys)3]− complex. The coordination mode was evaluated by fitting linear combinations of EXAFS oscillations to the experimental spectra, and by the 207Pb NMR signals in the chemical shift range δPb = 2006 – 2507 ppm, which became increasingly deshielded with increasing free cysteinate concentration. One-pulse magic angle spinning (MAS) 207Pb NMR spectra of crystalline Pb(aet)2 (Haet = 2-aminoethanethiol or cysteamine) with PbS2N2 coordination were measured for comparison (δiso = 2105 ppm). The UV-vis. spectra displayed absorption maxima at 298 – 300 nm (S− → PbII charge transfer) for the dithiolate PbS2N(N/O) species; with increasing ligand excess a shoulder appeared at ∼ 330 nm for the trithiolate PbS3N and PbS3 (minor) complexes. The results provide spectroscopic fingerprints for structural models for Pb(II) coordination modes to proteins and enzymes. PMID:25695880

  20. The initial pump-probe polarization anisotropy of colloidal PbS quantum dots

    DOE PAGES

    Park, Samuel; Baranov, Dmitry; Ryu, Jisu; ...

    2016-07-20

    Pump-probe polarization anisotropy measurements with 15 fs pulses are employed to investigate the electronic structure of PbS quantum dots. Here, the initial anisotropy at the bandgap is anomalously low (<0.1) and suggests large electronic couplings.

  1. "In the Footsteps of Alexander the Great" PBS Series. Teacher's Guide.

    ERIC Educational Resources Information Center

    Corporation for Public Broadcasting, Washington, DC.

    This teacher's guide correlates with the Public Broadcasting Service (PBS) television series "In the Footsteps of Alexander the Great" hosted by historian Michael Wood. The four episodes of the series are entitled: "Son of God"; "Lord of Asia"; "Across the Hindu Kush"; and "To the Ends of the…

  2. Note: Near infrared spectral and transient measurements of PbS quantum dots luminescence.

    PubMed

    Parfenov, P S; Litvin, A P; Ushakova, E V; Fedorov, A V; Baranov, A V; Berwick, K

    2013-11-01

    We describe an experimental setup for the characterization of luminescence from nanostructures. The setup is intended for steady-state and time-resolved luminescence measurements in the near-infrared region. The setup allows us to study spectral luminescence properties in the spectral range of 0.8-2.0 μm with high spectral resolution and kinetic luminescence properties between 0.8 and 1.7 μm with a time resolution of 3 ns. The capabilities of the system are illustrated by taking luminescence measurements from PbS quantum dots. We established the size dependencies of the optical properties of the PbS quantum dots over a wide spectral range. Finally, the energy transfer process was studied with a high temporal and spectral resolution.

  3. Treatment of high salinity brines by direct contact membrane distillation: Effect of membrane characteristics and salinity.

    PubMed

    Li, Jianfeng; Guan, Yunshan; Cheng, Fangqin; Liu, Yu

    2015-12-01

    Direct contact membrane distillation (DCMD) is one of the attractive technologies for high salinity brine treatment. In this study, four polytetrafluoroethylene (PTFE) membranes were examined in treating highly concentrated salt solutions. Results showed that non-supported membranes generally have a higher overall mass transfer coefficient but porosity seems to be the most important parameter controlling membrane flux and thermal efficiency. Supported membranes with large thickness had relatively higher thermal efficiency than small thickness. This can be attributed to their reduced heat loss through heat condition. In addition, KCl, NaCl and MgCl2 solutions showed distinct trends over flux decline at high salt concentrations (⩾2.0M). The difference in flux was largely due to the discrepancy in water activities of these solutions (KCl>NaCl>MgCl2). However, the effect of viscosity on permeate flux could not be neglected for MgCl2 at high salt concentrations as the suddenly increased viscosity could lead to serious temperature polarization. This study indicates that membrane distillation is a promising technology for high salinity brine treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Phosphorus sorption capacity of biochars varies with biochar type and salinity level.

    PubMed

    Dugdug, Abdelhafid Ahmed; Chang, Scott X; Ok, Yong Sik; Rajapaksha, Anushka Upamali; Anyia, Anthony

    2018-02-10

    Biochar is recognized as an effective material for recovering excess nutrients, including phosphorus (P), from aqueous solutions. Practically, that benefits the environment through reducing P losses from biochar-amended soils; however, how salinity influences P sorption by biochar is poorly understood and there has been no direct comparison on P sorption capacity between biochars derived from different feedstock types under non-saline and saline conditions. In this study, biochars derived from wheat straw, hardwood, and willow wood were used to compare P sorption at three levels of electrical conductivity (EC) (0, 4, and 8 dS m -1 ) to represent a wide range of salinity conditions. Phosphorus sorption by wheat straw and hardwood biochars increased as aqueous solution P concentration increased, with willow wood biochar exhibiting an opposite trend for P sorption. However, the pattern for P sorption became the same as the other biochars after the willow wood biochar was de-ashed with 1 M HCl and 0.05 M HF. Willow wood biochar had the highest P sorption (1.93 mg g -1 ) followed by hardwood (1.20 mg g -1 ) and wheat straw biochars (1.06 mg g -1 ) in a 25 mg L -1 P solution. Although the pH in the equilibrium solution was higher with willow wood biochar (~ 9.5) than with the other two biochars (~ 6.5), solution pH had no or minor effects on P sorption by willow wood biochar. The high sorption rate of P by willow wood biochar could be attributed to the higher concentrations of salt and other elements (i.e., Ca and Mg) in the biochar in comparison to that in wheat straw and hardwood biochars; the EC values were 2.27, 0.53, and 0.27 dS m -1 for willow wood, wheat straw, and hardwood biochars, respectively. A portion of P desorbed from the willow wood biochar; and that desorption increased with the decreasing P concentration in the aqueous solution. Salinity in the aqueous solution influenced P sorption by hardwood and willow wood but not by wheat straw

  5. Investigation of Lake Water Salinity by Using Four-Band Salinity Algorithm on WorldView-2 Satellite Image for a Saline Industrial Lake

    NASA Astrophysics Data System (ADS)

    Budakoǧlu, Murat; Karaman, Muhittin; Damla Uça Avcı, Z.; Kumral, Mustafa; Geredeli (Yılmaz), Serpil

    2014-05-01

    Salinity of a lake is an important characteristic since, these are potentially industrial lakes and the degree of salinity can significantly be used for determination of mineral resources and for the production management. In the literature, there are many studies of using satellite data for salinity related lake studies such as determination of salinity distribution and detection of potential freshwater sources in less salt concentrated regions. As the study area Lake Acigol, located in Denizli (Turkey) was selected. With it's saline environment, it's the major sodium sulphate production resource of Turkey. In this study, remote sensing data and data from a field study was used and correlated. Remote sensing is an efficient tool to monitor and analyze lake properties by using it complementary to field data. Worldview-2 satellite data was used in this study which consists of 8 bands. At the same time with the satellite data acquisition, a field study was conducted to collect the salinity values in 17 points of the laker with using YSI 556 Multiparametre for measurements. The values were measured as salinity amount in grams per kilogram solution and obtained as ppt unit. It was observed that the values vary from 34 ppt - 40.1 ppt and the average is 38.056 ppt. In Thalassic serie, the lake was in mixoeuhaline state in the time of issue. As a first step, ATCOR correction was performed on satellite image for atmospheric correction. There were some clouds on the lake field, hence it was decided to continue the study by using the 12 sampling points which were clear on the image. Then, for each sampling point, a spectral value was obtained by calculating the average at a 11*11 neighborhood. The relation between the spectral reflectance values and the salinity was investigated. The 4-band algorithm, which was used for determination of chlorophyll-a distribution in highly turbid coastal environment by Wei (2012) was applied. Salinity α (Λi-1 / Λj-1) * (Λk-1 / Λm-1) (i

  6. Facet-controlled facilitation of PbS nanoarchitectures by understanding nanocrystal growth

    NASA Astrophysics Data System (ADS)

    Loc, Welley Siu; Quan, Zewei; Lin, Cuikun; Pan, Jinfong; Wang, Yuxuan; Yang, Kaikun; Jian, Wen-Bin; Zhao, Bo; Wang, Howard; Fang, Jiye

    2015-11-01

    Nanostructured lead sulphide is a significant component in a number of energy-related sustainable applications such as photovoltaic cells and thermoelectric components. In many micro-packaging processes, dimensionality-controlled nano-architectures as building blocks with unique properties are required. This study investigates different facet-merging growth behaviors through a wet-chemical synthetic strategy to produce high-quality controlled nanostructures of lead sulphide in various dimensionalities. It was found that 1D nanowires or 2D nanosheets can be obtained by the merging of reactive {111}- or {110}-facets, respectively, while promoting {100} facets in the early stages after nucleation leads to the growth of 0D nanocubes. The influence of temperature, capping ligands and co-solvent in facilitating the crystal facet growth of each intermediate seed is also demonstrated. The novelty of this work is characterized by the delicate manipulation of various PbS nanoarchitectures based on the comprehension of the facet-merging evolution. The synthesis of facet-controlled PbS nanostructures could provide novel building blocks with desired properties for use in many applications.Nanostructured lead sulphide is a significant component in a number of energy-related sustainable applications such as photovoltaic cells and thermoelectric components. In many micro-packaging processes, dimensionality-controlled nano-architectures as building blocks with unique properties are required. This study investigates different facet-merging growth behaviors through a wet-chemical synthetic strategy to produce high-quality controlled nanostructures of lead sulphide in various dimensionalities. It was found that 1D nanowires or 2D nanosheets can be obtained by the merging of reactive {111}- or {110}-facets, respectively, while promoting {100} facets in the early stages after nucleation leads to the growth of 0D nanocubes. The influence of temperature, capping ligands and co-solvent in

  7. Cryoelectrolysis-electrolytic processes in a frozen physiological saline medium.

    PubMed

    Lugnani, Franco; Macchioro, Matteo; Rubinsky, Boris

    2017-01-01

    Cryoelectrolysis is a new minimally invasive tissue ablation surgical technique that combines the ablation techniques of electrolytic ablation with cryosurgery. The goal of this study is to examine the hypothesis that electrolysis can take place in a frozen aqueous saline solution. To examine the hypothesis we performed a cryoelectrolytic ablation protocol in which electrolysis and cryosurgery are delivered simultaneously in a tissue simulant made of physiological saline gel with a pH dye. We measured current flow, voltage and extents of freezing and pH dye staining. Using optical measurements and measurements of currents, we have shown that electrolysis can occur in frozen physiological saline, at high subzero freezing temperatures, above the eutectic temperature of the frozen salt solution. It was observed that electrolysis occurs when the tissue resides at high subzero temperatures during the freezing stage and essentially throughout the entire thawing stage. We also found that during thawing, the frozen lesion temperature raises rapidly to high subfreezing values and remains at those values throughout the thawing stage. Substantial electrolysis occurs during the thawing stage. Another interesting finding is that electro-osmotic flows affect the process of cryoelectrolysis at the anode and cathode, in different ways. The results showing that electrical current flow and electrolysis occur in frozen saline solutions imply a mechanism involving ionic movement in the fluid concentrated saline solution channels between ice crystals, at high subfreezing temperatures. Temperatures higher than the eutectic are required for the brine to be fluid. The particular pattern of temperature and electrical currents during the thawing stage of frozen tissue, can be explained by the large amounts of energy that must be removed at the outer edge of the frozen lesion because of the solid/liquid phase transformation on that interface. Electrolysis can occur in a frozen domain at high

  8. Modeling as a tool for management of saline soils and irrigation waters

    USDA-ARS?s Scientific Manuscript database

    Optimal management of saline soils and irrigation waters requires consideration of many interrelated factors including, climate, water applications and timing, water flow, plant water uptake, soil chemical reactions, plant response to salinity and solution composition, soil hydraulic properties and ...

  9. Enhancement of nitrate uptake and growth of barley seedlings by calcium under saline conditions

    NASA Technical Reports Server (NTRS)

    Ward, M. R.; Aslam, M.; Huffaker, R. C.

    1986-01-01

    The effect of Ca2+ on NO3- assimilation in young barley (Hordeum vulgare L. var CM 72) seedlings in the presence and absence of NaCl was studied. Calcium increased the activity of the NO3- transporter under saline conditions, but had little effect under nonsaline conditions. Calcium decreased the induction period for the NO3- transporter under both saline and nonsaline conditions but had little effect on its apparent Km for NO3- both in the presence and absence of NaCl. The enhancement of NO3- transport by Ca2+ under saline conditions was dependent on the presence of Ca2+ in the uptake solution along with the salt, since Ca2+ had no effect when supplied before or after salinity stress. Although Mn2+ and Mg2+ enhanced NO3- uptake under saline conditions, neither was as effective as Ca2+. In longer studies, increasing the Ca2+ concentration in saline nutrient solutions resulted in increases in NO3- assimilation and seedling growth.

  10. Dissolution of man-made vitreous fibers in rat alveolar macrophage culture and Gamble's saline solution: influence of different media and chemical composition of the fibers.

    PubMed Central

    Luoto, K; Holopainen, M; Karppinen, K; Perander, M; Savolainen, K

    1994-01-01

    The effect of different chemical compositions of man-made vitreous fibers (MMVF) on their dissolution by alveolar macrophages (AM) in culture and in Gamble's solution was studied. The fibers were exposed to cultured rat AMs, culture medium alone; or Gamble's saline solution for 2, 4, or 8 days. The dissolution of the fibers was studied by measuring the amount of silicon (Si), iron (Fe), and aluminum (Al) in each medium. The AMs in culture dissolved Fe and Al from the fibers but the dissolution of Si was more marked in the cell culture medium without cells and in the Gamble's solution. The dissolution of Si, Fe, and Al was different for different fibers, and increased as a function of time. The Fe and Al content of the fibers correlated negatively with the dissolution of Si by AMs from the MMVF, i.e., when the content of Fe and Al of the fibers increased the dissolution of Si decreased. These results suggest that the chemical composition of MMVFs has a marked effect on their dissolution. AMs seem to affect the dissolution of Fe and Al from the fibers. This suggests that in vitro models with cells in the media rather than only culture media or saline solutions would be preferable in dissolution studies of MMVFs. PMID:7882911

  11. On the flocculation and settling characteristics of low- and high-concentration sediment suspensions: effects of particle concentration and salinity conditions.

    PubMed

    Zhu, Zhongfan; Xiong, Xiangzhong; Liang, Chaohuang; Zhao, Ming

    2018-05-01

    It remains unclear how the primary particle concentration and salinity conditions influence the flocculation and settling characteristics of water-sediment suspensions. In this study, two sets of experiments were performed to examine the flocculation and settling properties of low- and high-concentration sediment suspensions. In low-concentration suspensions, the sediment concentration undergoes a rapid initial decrease followed by a slow decrease until it approaches zero with increasing flocculation time. Increases in salinity or the valence of cations from the saline solution added to the suspension lead to a more rapidly decreasing sediment concentration with flocculation time. The valence of cations from the saline solution has a larger influence on the flocculation-settling behaviours of the suspension than the salinity. In high-concentration sediment suspensions, the height of the clear water-turbid water interface in the water-sediment suspension experiences an initial, rapidly decreasing phase followed by a slowly decreasing phase with increasing flocculation time. Increasing the primary particle concentration, salinity or valence of cations from the saline solution added to the suspension causes the height reduction of the clear water-turbid water interface to become gentler. Finally, the valence of cations from the saline solution has a greater influence on the settling characteristics of the high-concentration water-sediment suspension than the salinity.

  12. Susceptibility of nitinol to localized corrosion.

    PubMed

    Pound, Bruce G

    2006-04-01

    The effect of different conditions on the susceptibility of nitinol to localized corrosion was examined using the cyclic potentiodynamic polarization technique. Tests were performed on mechanically polished (MP) and electropolished (EP) nitinol wire in 0.9 wt % NaCl and phosphate-buffered saline (PBS). A polarization curve was also obtained for an EP stent in the NaCl. Differences between the breakdown potential and the corrosion potential (E(corr)) and between the protection potential and E(corr) were used to evaluate the susceptibility to pitting corrosion and crevice corrosion, respectively. The type of solution and, particularly, the surface condition affected the resistance of nitinol to pitting corrosion. Both EP and MP nitinol were more susceptible to breakdown in the NaCl than in PBS, indicating that the NaCl provides a more severe test environment than does PBS. Electropolishing increased the breakdown resistance of nitinol in PBS and the NaCl, as found in previous studies with Hank's solution. Surface condition, however, did not have a significant effect on the repassivation behavior of nitinol, as is also the case with titanium. The EP wire and stent showed similar breakdown and repassivation behavior in the NaCl, suggesting that the nature of the EP surface was similar in both cases. (c) 2005 Wiley Periodicals, Inc.

  13. A Study on Factors Affecting the Degradation of Magnesium and a Magnesium-Yttrium Alloy for Biomedical Applications

    PubMed Central

    Johnson, Ian; Liu, Huinan

    2013-01-01

    Controlling degradation of magnesium or its alloys in physiological saline solutions is essential for their potential applications in clinically viable implants. Rapid degradation of magnesium-based materials reduces the mechanical properties of implants prematurely and severely increases alkalinity of the local environment. Therefore, the objective of this study is to investigate the effects of three interactive factors on magnesium degradation, specifically, the addition of yttrium to form a magnesium-yttrium alloy versus pure magnesium, the metallic versus oxide surfaces, and the presence versus absence of physiological salt ions in the immersion solution. In the immersion solution of phosphate buffered saline (PBS), the magnesium-yttrium alloy with metallic surface degraded the slowest, followed by pure magnesium with metallic or oxide surfaces, and the magnesium-yttrium alloy with oxide surface degraded the fastest. However, in deionized (DI) water, the degradation rate showed a different trend. Specifically, pure magnesium with metallic or oxide surfaces degraded the slowest, followed by the magnesium-yttrium alloy with oxide surface, and the magnesium-yttrium alloy with metallic surface degraded the fastest. Interestingly, only magnesium-yttrium alloy with metallic surface degraded slower in PBS than in DI water, while all the other samples degraded faster in PBS than in DI water. Clearly, the results showed that the alloy composition, presence or absence of surface oxide layer, and presence or absence of physiological salt ions in the immersion solution all influenced the degradation rate and mode. Moreover, these three factors showed statistically significant interactions. This study revealed the complex interrelationships among these factors and their respective contributions to degradation for the first time. The results of this study not only improved our understanding of magnesium degradation in physiological environment, but also presented the key

  14. Biotin-decorated silica coated PbS nanocrystals emitting in the second biological near infrared window for bioimaging

    NASA Astrophysics Data System (ADS)

    Corricelli, M.; Depalo, N.; di Carlo, E.; Fanizza, E.; Laquintana, V.; Denora, N.; Agostiano, A.; Striccoli, M.; Curri, M. L.

    2014-06-01

    Nanoparticles (NPs) emitting in the second biological near infrared (NIR) window of the electromagnetic spectrum have been successfully synthesized by growing a silica shell on the hydrophobic surface of OLEA/TOP PbS nanocrystals (NCs), by means of a reverse microemulsion approach, and subsequently decorated with biotin molecules. The fabrication of very uniform and monodisperse NPs, formed of SiO2 shell coated single core PbS NCs, has been demonstrated by means of a set of complementary optical and structural techniques (Vis-NIR absorption and photoluminescence spectroscopy, transmission electron microscopy) that have highlighted how experimental parameters, such as PbS NC and silica precursor concentration, are crucial to direct the morphology and optical properties of silica coated PbS NPs. Subsequently, the silica surface of the core-shell NPs has been grafted with amino groups, in order to achieve covalent binding of biotin to NIR emitting silica coated NPs. Finally the successful reaction with a green-fluorescent labelled streptavidin has verified the molecular recognition response of the biotin molecules decorating the PbS@SiO2 NP surface. Dynamic light scattering (DLS) and ζ-potential techniques have been used to monitor the hydrodynamic diameter and colloidal stability of both PbS@SiO2 and biotin decorated NPs, showing their high colloidal stability in physiological media, as needed for biomedical applications. Remarkably the obtained biotinylated PbS@SiO2 NPs have been found to retain emission properties in the `second optical window' of the NIR region of the electromagnetic spectrum, thus representing attractive receptor-targeted NIR fluorescent probes for in vivo tumour imaging.Nanoparticles (NPs) emitting in the second biological near infrared (NIR) window of the electromagnetic spectrum have been successfully synthesized by growing a silica shell on the hydrophobic surface of OLEA/TOP PbS nanocrystals (NCs), by means of a reverse microemulsion

  15. 2012 Context Study of the Use of Technology and PBS KIDS Transmedia in the Home Environment: A Report to the CPB-PBS "Ready to Learn Initiative"

    ERIC Educational Resources Information Center

    Pasnik, Shelley; Llorente, Carlin

    2012-01-01

    The CPB-PBS Ready To Learn initiative, funded by the U. S. Department of Education, brings engaging, high-quality media to young children who may be at risk for academic difficulties due to economic and social disadvantages. The initiative aims to deliver early mathematics and literacy resources on new and emerging digital platforms such as tablet…

  16. 37 CFR 253.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... background or theme music in a PBS program: 2003-2007 $56.81 (3) For performance of such a work in a feature... music in a program of a station of PBS: 2003-2007 $4.04 (5) For the performance of such a work in a... theme music in an NPR program: 2003-2007 $5.51 (7) For the performance of such a work in a feature...

  17. 37 CFR 381.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... background or theme music in a PBS program: 2008-2012 $57.66 (3) For performance of such a work in a feature... music in a program of a station of PBS: 2008-2012 $4.10 (5) For the performance of such a work in a... theme music in an NPR program: 2008-2012 $5.59 (7) For the performance of such a work in a feature...

  18. 37 CFR 381.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... background or theme music in a PBS program: 2008-2012 $57.66 (3) For performance of such a work in a feature... music in a program of a station of PBS: 2008-2012 $4.10 (5) For the performance of such a work in a... theme music in an NPR program: 2008-2012 $5.59 (7) For the performance of such a work in a feature...

  19. 37 CFR 381.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... background or theme music in a PBS program: 2008-2012 $57.66 (3) For performance of such a work in a feature... music in a program of a station of PBS: 2008-2012 $4.10 (5) For the performance of such a work in a... theme music in an NPR program: 2008-2012 $5.59 (7) For the performance of such a work in a feature...

  20. 37 CFR 253.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... performance of such a work as background or theme music in a PBS program: 2003-2007 $56.81 (3) For performance... such a work as background or theme music in a program of a station of PBS: 2003-2007 $4.04 (5) For the... a work as background or theme music in an NPR program: 2003-2007 $5.51 (7) For the performance of...

  1. 37 CFR 253.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... background or theme music in a PBS program: 2003-2007 $56.81 (3) For performance of such a work in a feature... music in a program of a station of PBS: 2003-2007 $4.04 (5) For the performance of such a work in a... theme music in an NPR program: 2003-2007 $5.51 (7) For the performance of such a work in a feature...

  2. 37 CFR 253.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... background or theme music in a PBS program: 2003-2007 $56.81 (3) For performance of such a work in a feature... music in a program of a station of PBS: 2003-2007 $4.04 (5) For the performance of such a work in a... theme music in an NPR program: 2003-2007 $5.51 (7) For the performance of such a work in a feature...

  3. 37 CFR 381.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... background or theme music in a PBS program: 2013-2017 $58.51 (3) For performance of such a work in a feature... music in a program of a station of PBS: 2013-2017 $4.18 (5) For the performance of such a work in a... theme music in an NPR program: 2013-2017 $5.70 (7) For the performance of such a work in a feature...

  4. 37 CFR 253.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... background or theme music in a PBS program: 2003-2007 $56.81 (3) For performance of such a work in a feature... music in a program of a station of PBS: 2003-2007 $4.04 (5) For the performance of such a work in a... theme music in an NPR program: 2003-2007 $5.51 (7) For the performance of such a work in a feature...

  5. 37 CFR 381.4 - Performance of musical compositions by PBS, NPR and other public broadcasting entities engaged in...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... background or theme music in a PBS program: 2013-2017 $58.51 (3) For performance of such a work in a feature... music in a program of a station of PBS: 2013-2017 $4.18 (5) For the performance of such a work in a... theme music in an NPR program: 2013-2017 $5.70 (7) For the performance of such a work in a feature...

  6. Salinity and hydrology of closed lakes

    USGS Publications Warehouse

    Langbein, Walter Basil

    1961-01-01

    Lakes without outlets, called closed lakes, are exclusively features of the arid and semiarid zones where annual evaporation exceeds rainfall. The number of closed lakes increases with aridity, so there are relatively few perennial closed lakes, but "dry" lakes that rarely contain water are numerous.Closed lakes fluctuate in level to a much greater degree than the open lakes of the humid zone, because variations in inflow can be compensated only by changes in surface area. Since the variability of inflow increases with aridity, it is possible to derive an approximate relationship for the coefficient of variation of lake area in terms of data on rates of evaporation, lake area, lake depth, and drainage area.The salinity of closed lakes is highly variable, ranging from less than 1 percent to over 25 percent by weight of salts. Some evidence suggests that the tonnage of salts in a lake solution is substantially less than the total input of salts into the lake over the period of existence of the closed lake. This evidence suggests further that the salts in a lake solution represent a kind of long-term balance between factors of gain and loss of salts from the solution.Possible mechanisms for the loss of salts dissolved in the lake include deposition in marginal bays, entrapment in sediments, and removal by wind. Transport of salt from the lake surface in wind spray is also a contributing, but seemingly not major, factor.The hypothesis of a long-term balance between input to and losses from the lake solution is checked by deriving a formula for the equilibrium concentration and comparing the results with the salinity data. The results indicate that the reported salinities seemingly can be explained in terms of their geometric properties and hydrologic environment.The time for accumulation of salts in the lake solution the ratio between mass of salts in the solution and the annual input may also be estimated from the geometric and hydrologic factors, in the absence of

  7. Interfacial dynamic surface traps of lead sulfide (PbS) nanocrystals: test-platform for interfacial charge carrier traps at the organic/inorganic functional interface

    NASA Astrophysics Data System (ADS)

    Kim, Youngjun; Ko, Hyungduk; Park, Byoungnam

    2018-04-01

    Nanocrystal (NC) size and ligand dependent dynamic trap formation of lead sulfide (PbS) NCs in contact with an organic semiconductor were investigated using a pentacene/PbS field effect transistor (FET). We used a bilayer pentacene/PbS FET to extract information of the surface traps of PbS NCs at the pentacene/PbS interface through the field effect-induced charge carrier density measurement in the threshold and subthreshold regions. PbS size and ligand dependent trap properties were elucidated by the time domain and threshold voltage measurements in which threshold voltage shift occurs by carrier charging and discharging in the trap states of PbS NCs. The observed threshold voltage shift is interpreted in context of electron trapping through dynamic trap formation associated with PbS NCs. To the best of our knowledge, this is the first demonstration of the presence of interfacial dynamic trap density of PbS NC in contact with an organic semiconductor (pentacene). We found that the dynamic trap density of the PbS NC is size dependent and the carrier residence time in the specific trap sites is more sensitive to NC size variation than to NC ligand exchange. The probing method presented in the study offers a means to investigate the interfacial surface traps at the organic-inorganic hetero-junction, otherwise understanding of the buried surface traps at the functional interface would be elusive.

  8. Normal saline solution versus other viscous solutions for submucosal injection during endoscopic mucosal resection: a systematic review and meta-analysis.

    PubMed

    Yandrapu, Harathi; Desai, Madhav; Siddique, Sameer; Vennalganti, Prashanth; Vennalaganti, Sreekar; Parasa, Sravanthi; Rai, Tarun; Kanakadandi, Vijay; Bansal, Ajay; Titi, Mohammad; Repici, Alessandro; Bechtold, Matthew L; Sharma, Prateek; Choudhary, Abhishek

    2017-04-01

    EMR is being increasingly practiced for the removal of large colorectal polyps. A variety of solutions such as normal saline solution (NS) and other viscous and hypertonic solutions (VS) have been used as submucosal injections for EMR. A systematic review and meta-analysis is presented comparing the efficacy and adverse events of EMR performed using NS versus VS. Two independent reviewers conducted a search of all databases for human, randomized controlled trials that compared NS with VS for EMR of colorectal polyps. Data on complete en bloc resection, presence of residual lesions, and adverse events were extracted using a standardized protocol. Pooled odds ratio (OR) estimates along with 95% confidence intervals (CI) were calculated using fixed effect or random effects models. Five prospective, randomized controlled trials (504 patients) met the inclusion criteria. The mean polyp sizes were 20.84 mm with NS and 21.44 mm with VS. On pooled analysis, a significant increase in en bloc resection (OR, 1.91; 95% CI, 1.11-3.29; P = .02; I 2  = 0%) and decrease in residual lesions (OR, 0.54; 95% CI, 0.32-0.91; P = .02; I 2  = 0%) were noted in VS compared with NS. There was no significant difference in the rate of overall adverse events between the 2 groups. Use of VS during EMR leads to higher rates of en bloc resection and lower rates of residual lesions compared with NS, without any significant difference in adverse events. Endoscopists could consider using VS for EMR of large colorectal polyps and NS for smaller polyps because there is no significant difference in the outcomes with lesions <2 cm. Published by Elsevier Inc.

  9. Optical properties of DNA induced starch capped PbS, CdS and PbS/CdS nanocomposites

    NASA Astrophysics Data System (ADS)

    Das, D.; Konwar, R.; Kalita, P. K.

    2015-08-01

    Starch capped PbS, CdS and PbS-CdS nanocomposites are conjugated with Calf-Thymus DNA. All the materials are characterized by X-ray diffraction, high-resolution transmission electron microscopy, UV-Vis spectroscopy and photoluminescence spectroscopy. The x-ray diffraction patterns of PbS and CdS show that the materials possess polycrystalline having both cubic and hexagonal phases. High resolution transmission electron microscopic results (HRTEM) shows PbS nanoparticles of size 3 nm and that of CdS nanoparticles having average size 4 nm which exhibit tendency of agglomeration. In case of PbS/CdS, it exhibits different types of nanosheets. The UV absorption spectra of all the samples exhibit clear blue-shift with the respective bulk absorption edges. This is attributed to the strong quantum confinement in the materials. The absorption spectra also exhibit increase of the band gaps from 2.25 to 4.35 eV for PbS; 2.25-4.2 eV for CdS with decrease of molarities from 0.1 to 0.001 M as well as conjugated with DNA. The photoluminescence spectra of all PbS, CdS and PbS/CdS composites synthesized at 0.1 M molar concentration show a further blue shift and an enhancement of intensity after conjugation with DNA, but the effect is reversed i.e. occurrence of red shift and reduction of intensity for those having 0.01 M. This is due to the two competing processes of surface passivation as well as stabilization of nanocomposites governed by bio-molecules and that of Dexter energy transfer with the effective charge separation. The result shows the applicability of the materials in development of biological labels and biosensors.

  10. Facet-controlled facilitation of PbS nanoarchitectures by understanding nanocrystal growth.

    PubMed

    Loc, Welley Siu; Quan, Zewei; Lin, Cuikun; Pan, Jinfong; Wang, Yuxuan; Yang, Kaikun; Jian, Wen-Bin; Zhao, Bo; Wang, Howard; Fang, Jiye

    2015-12-07

    Nanostructured lead sulphide is a significant component in a number of energy-related sustainable applications such as photovoltaic cells and thermoelectric components. In many micro-packaging processes, dimensionality-controlled nano-architectures as building blocks with unique properties are required. This study investigates different facet-merging growth behaviors through a wet-chemical synthetic strategy to produce high-quality controlled nanostructures of lead sulphide in various dimensionalities. It was found that 1D nanowires or 2D nanosheets can be obtained by the merging of reactive {111}- or {110}-facets, respectively, while promoting {100} facets in the early stages after nucleation leads to the growth of 0D nanocubes. The influence of temperature, capping ligands and co-solvent in facilitating the crystal facet growth of each intermediate seed is also demonstrated. The novelty of this work is characterized by the delicate manipulation of various PbS nanoarchitectures based on the comprehension of the facet-merging evolution. The synthesis of facet-controlled PbS nanostructures could provide novel building blocks with desired properties for use in many applications.

  11. Off-Resonance Photosensitization of a Photorefractive Polymer Composite Using PbS Nanocrystals

    DOE PAGES

    Moon, Jong-Sik; Liang, Yichen; Stevens, Tyler E.; ...

    2015-05-26

    The photosensitization of photorefractive polymeric composites for operation at 633 nm is accomplished through the inclusion of narrow band gap semiconductor nanocrystals composed of PbS. Unlike previous studies involving photosensitization of photorefractive polymer composites with inorganic nanocrystals, we employ an off-resonance approach where the first excitonic transition associated with the PbS nanocrystals lies at ~1220 nm and not the wavelength of operation. Using this methodology, internal diffraction efficiencies exceeding 82%, two-beam-coupling gain coefficients of 211 cm –1, and response times of 34 ms have been observed, representing some of the best figures of merit reported for this class of materials.more » Furthermore, these data demonstrate the ability of semiconductor nanocrystals to compete effectively with traditional organic photosensitizers. In addition to superior performance, this approach also offers an inexpensive and easy means by which to photosensitize composite materials. Additionally, the photoconductive characteristics of the composites used for this study will also be considered.« less

  12. Structure, molecular simulation, and release of aspirin from intercalated Zn-Al-layered double hydroxides.

    PubMed

    Meng, Zilin; Li, Xiaowei; Lv, Fengzhu; Zhang, Qian; Chu, Paul K; Zhang, Yihe

    2015-11-01

    Aspirin or acetylsalicylic acid (AA), a non-steroidal anti-inflammatory drug, is intercalated into Zn-Al-layered double hydroxides (ZnAl-LDHs) by co-precipitation and reconstruction methods. The composition, structure, and morphology of the intercalated products as well as their release behavior are determined experimentally and theoretically by Material Studio 5.5. Experimental results disclose the strong interaction between the LDHs sheets and AA in the intercalated ZnAl-LDHs produced by co-precipitation and slow release of AA from the intercalated ZnAl-LDHs in both phosphate buffered saline (PBS) and borate buffered saline (BBS) solutions. The percentage of AA released from the ZnAl-LDHs prepared by both methods in PBS (96.87% and 98.12%) are much more than those in BBS (68.59% and 81.22%) implying that both H4BO4(-) and H2PO4(-) can exchange with AA in the ZnAl-LDHs. After AA is released to PBS, ZnAl-LDHs break into small pieces. The experimental results are explained theoretically based on the calculation of the bonding energy between the anions and LDHs sheets as well as the AlO bond length change in the LDHs sheets. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Probing surface states in PbS nanocrystal films using pentacene field effect transistors: controlling carrier concentration and charge transport in pentacene.

    PubMed

    Park, Byoungnam; Whitham, Kevin; Bian, Kaifu; Lim, Yee-Fun; Hanrath, Tobias

    2014-12-21

    We used a bilayer field effect transistor (FET) consisting of a thin PbS nanocrystals (NCs) film interfaced with vacuum-deposited pentacene to probe trap states in NCs. We interpret the observed threshold voltage shift in context of charge carrier trapping by PbS NCs and relate the magnitude of the threshold voltage shift to the number of trapped carriers. We explored a series of NC surface ligands to modify the interface between PbS NCs and pentacene and demonstrate the impact of interface chemistry on charge carrier density and the FET mobility in a pentacene FET.

  14. Macrophage Biocompatibility of CoCr Wear Particles Produced under Polarization in Hyaluronic Acid Aqueous Solution

    PubMed Central

    Perez-Maceda, Blanca Teresa; López-Fernández, María Encarnación; Díaz, Iván; Kavanaugh, Aaron; Billi, Fabrizio; Escudero, María Lorenza; García-Alonso, María Cristina; Lozano, Rosa María

    2018-01-01

    Macrophages are the main cells involved in inflammatory processes and in the primary response to debris derived from wear of implanted CoCr alloys. The biocompatibility of wear particles from a high carbon CoCr alloy produced under polarization in hyaluronic acid (HA) aqueous solution was evaluated in J774A.1 mouse macrophages cultures. Polarization was applied to mimic the electrical interactions observed in living tissues. Wear tests were performed in a pin-on-disk tribometer integrating an electrochemical cell in phosphate buffer solution (PBS) and in PBS supplemented with 3 g/L HA, an average concentration that is generally found in synovial fluid, used as lubricant solution. Wear particles produced in 3 g/L HA solution showed a higher biocompatibility in J774A.1 macrophages in comparison to those elicited by particles obtained in PBS. A considerable enhancement in macrophages biocompatibility in the presence of 3 g/L of HA was further observed by the application of polarization at potentials having current densities typical of injured tissues suggesting that polarization produces an effect on the surface of the metallic material that leads to the production of wear particles that seem to be macrophage-biocompatible and less cytotoxic. The results showed the convenience of considering the influence of the electric interactions in the chemical composition of debris detached from metallic surfaces under wear corrosion to get a better understanding of the biological effects caused by the wear products. PMID:29738506

  15. Enhanced production of human influenza virus in PBS-12SF cells with a reduced interferon response.

    PubMed

    Carvajal-Yepes, Monica; Sporer, Kelly R B; Carter, Jenna L; Colvin, Christopher J; Coussens, Paul M

    2015-01-01

    Influenza is one of the most important infectious diseases in humans. The best way to prevent severe illness caused by influenza infection is vaccination. Cell culture-derived influenza vaccines are being considered in addition to the widely used egg-based system in order to support the increasing seasonal demand and to be prepared in case of a pandemic. Cell culture based systems offer increased safety, capacity, and flexibility with reduced downstream processing relative to embryonated eggs. We have previously reported a chick embryo cell line, termed PBS-12SF, that supports replication of human and avian influenza A viruses to high titers (>10(7) PFU/ml) without the need for exogenous proteases or serum proteins. Viral infections in cells are limited by the Interferon (IFN) response typified by production of type I IFNs that bind to the IFNα/β receptor and activate an antiviral state. In this study, we investigated how neutralizing the interferon (IFN) response in PBS-12SF cells, via shRNA-mediated knock-down of IFNAR1 mRNA expression, affects influenza virus production. We were successful in knocking down ∼90% of IFNAR1 protein expression by this method, resulting in a significant decrease in the response to recombinant chIFNα stimulation in PBS-12SF cells as shown by a reduction in expression of interferon-responsive genes when compared to control cells. Additionally; IFNAR1-knock-down cells displayed enhanced viral HA production and released more virus into cell culture supernatants than parental PBS-12SF cells.

  16. Cryoelectrolysis—electrolytic processes in a frozen physiological saline medium

    PubMed Central

    Lugnani, Franco; Macchioro, Matteo

    2017-01-01

    Background Cryoelectrolysis is a new minimally invasive tissue ablation surgical technique that combines the ablation techniques of electrolytic ablation with cryosurgery. The goal of this study is to examine the hypothesis that electrolysis can take place in a frozen aqueous saline solution. Method To examine the hypothesis we performed a cryoelectrolytic ablation protocol in which electrolysis and cryosurgery are delivered simultaneously in a tissue simulant made of physiological saline gel with a pH dye. We measured current flow, voltage and extents of freezing and pH dye staining. Results Using optical measurements and measurements of currents, we have shown that electrolysis can occur in frozen physiological saline, at high subzero freezing temperatures, above the eutectic temperature of the frozen salt solution. It was observed that electrolysis occurs when the tissue resides at high subzero temperatures during the freezing stage and essentially throughout the entire thawing stage. We also found that during thawing, the frozen lesion temperature raises rapidly to high subfreezing values and remains at those values throughout the thawing stage. Substantial electrolysis occurs during the thawing stage. Another interesting finding is that electro-osmotic flows affect the process of cryoelectrolysis at the anode and cathode, in different ways. Discussion The results showing that electrical current flow and electrolysis occur in frozen saline solutions imply a mechanism involving ionic movement in the fluid concentrated saline solution channels between ice crystals, at high subfreezing temperatures. Temperatures higher than the eutectic are required for the brine to be fluid. The particular pattern of temperature and electrical currents during the thawing stage of frozen tissue, can be explained by the large amounts of energy that must be removed at the outer edge of the frozen lesion because of the solid/liquid phase transformation on that interface. Conclusion

  17. Comparative Analysis of Two Biological Warfare Air Samplers Using Live Surrogate Agents

    DTIC Science & Technology

    2012-03-01

    extensively for Phosphate Buffer Saline (PBS) solution and water , and, to a very limited degree in AF evaluations, for virus preserving media, specifically...or water . Furthermore, viral studies have been conducted comparing the effectiveness of utilizing the reduced secondary flow rate on the XMX/2L...with using bioagent aerosols rated BSL-2 or higher. Male Specific Coliphage 2 (MS2), American Type Culture Collection (ATCC) 15597-B1, was selected

  18. Korean Hemorrhagic Fever.

    DTIC Science & Technology

    1981-03-31

    secretions, and ectoparasites were prepared in phosphate buffered saline, pH 7.6 containing 0.2% serum bovine albumin(PBS). Penicillin, streptomycin...water source and urine was collected during an interval of 3-5 hours, in sterile bottles containing 10 ml of Hanks balanced solution(BSS) with 1% bovine ...Shope, R. E. and Harrison, A. Physiocochemical and morphological relationships of some arthropod-borne viruses to bluetongue virus - a new taxonomic

  19. The PBS Triangle: Does It Fit as a Heuristic? A Reflection on the First International Conference on Positive Behavior Support

    ERIC Educational Resources Information Center

    Baker, Candace Kay

    2005-01-01

    In this article, the author explores the evolution of the use of the triangle as a communication tool for describing positive behavior support (PBS) systems. The conceptual framework for the triangle used for PBS is credited to Walker et al. In that seminal work, the a model of school-based prevention strategies for children displaying antisocial…

  20. Electrochemical surface-enhanced Raman scattering measurement on ligand capped PbS quantum dots at gap of Au nanodimer

    NASA Astrophysics Data System (ADS)

    Li, Xiaowei; Minamimoto, Hiro; Murakoshi, Kei

    2018-05-01

    The vibrational characteristics of ligand-capped lead sulfide (PbS) quantum dots (QDs) were clarified via electrochemical surface-enhanced Raman spectroscopy (EC-SERS) using a hybridized system of gold (Au) nanodimers and PbS QDs under electrochemical potential control. Enhanced electromagnetic field caused by the coupling of QDs with plasmonic Au nanodimers allowed the characteristic behavior of the ligand oleic acid (OA) on the PbS QD surface to be detected under electrochemical potential control. Binding modes between the QDs and OA molecules were characterized using synchronous two-dimensional correlation spectra at distinct electrochemical potentials, confirming that the bidentate bridging mode was probably the most stable mode even under relatively negative potential polarization. Changes in binding modes and molecular orientations resulted in fluctuations in EC-SERS spectra. The present observations strongly recommend the validity of the QD-plasmonic nanostructure coupled system for sensitive molecular detection via EC-SERS.

  1. Experimental Influences in the Accurate Measurement of Cartilage Thickness in MRI.

    PubMed

    Wang, Nian; Badar, Farid; Xia, Yang

    2018-01-01

    Objective To study the experimental influences to the measurement of cartilage thickness by magnetic resonance imaging (MRI). Design The complete thicknesses of healthy and trypsin-degraded cartilage were measured at high-resolution MRI under different conditions, using two intensity-based imaging sequences (ultra-short echo [UTE] and multislice-multiecho [MSME]) and 3 quantitative relaxation imaging sequences (T 1 , T 2 , and T 1 ρ). Other variables included different orientations in the magnet, 2 soaking solutions (saline and phosphate buffered saline [PBS]), and external loading. Results With cartilage soaked in saline, UTE and T 1 methods yielded complete and consistent measurement of cartilage thickness, while the thickness measurement by T 2 , T 1 ρ, and MSME methods were orientation dependent. The effect of external loading on cartilage thickness is also sequence and orientation dependent. All variations in cartilage thickness in MRI could be eliminated with the use of a 100 mM PBS or imaged by UTE sequence. Conclusions The appearance of articular cartilage and the measurement accuracy of cartilage thickness in MRI can be influenced by a number of experimental factors in ex vivo MRI, from the use of various pulse sequences and soaking solutions to the health of the tissue. T 2 -based imaging sequence, both proton-intensity sequence and quantitative relaxation sequence, similarly produced the largest variations. With adequate resolution, the accurate measurement of whole cartilage tissue in clinical MRI could be utilized to detect differences between healthy and osteoarthritic cartilage after compression.

  2. Efficient 3M PBS enhancing miniature projection optics

    NASA Astrophysics Data System (ADS)

    Yun, Zhisheng; Nevitt, Timothy; Willett, Stephen; Mortenson, Dave; Le, John; McDowell, Erin; Kent, Susan; Wong, Timothy; Beniot, Gilles J.; Ouderkirk, Andrew

    2016-09-01

    Over the past decade, 3M has developed a number of mobile projectors, with a goal towards providing the world's smallest, most efficient projection systems. Compact size and efficiency are required characteristics for projection systems used in mobile devices and more lately, in augmented reality systems. In this paper we summarize the main generations of 3M light engine optical designs. We present the optical architectures of four light engines, including the rationale behind the illumination designs and the projection systems. In particular, we describe various configurations relating to the 3M polarizing beam splitter (PBS) which is key to enhanced efficiency of the miniature projection systems.

  3. 16 CFR 1500.134 - Policy on first aid labeling for saline emesis.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Policy on first aid labeling for saline... REGULATIONS § 1500.134 Policy on first aid labeling for saline emesis. (a) This section states the Consumer Product Safety Commission's policy concerning first aid instructions for the use of a salt solution to...

  4. Lead(II) complex formation with l-cysteine in aqueous solution

    DOE PAGES

    Jalilehvand, Farideh; Sisombath, Natalie S.; Schell, Adam C.; ...

    2015-02-19

    The lead(II) complexes formed with the multidentate chelator l-cysteine (H 2Cys) in an alkaline aqueous solution were studied using 207Pb, 13C, and 1H NMR, Pb L III-edge X-ray absorption, and UV–vis spectroscopic techniques, complemented by electrospray ion mass spectrometry (ESI-MS). The H 2Cys/Pb II mole ratios were varied from 2.1 to 10.0 for two sets of solutions with C PbII = 0.01 and 0.1 M, respectively, prepared at pH values (9.1–10.4) for which precipitates of lead(II) cysteine dissolved. At low H 2Cys/Pb II mole ratios (2.1–3.0), a mixture of the dithiolate [Pb(S,N-Cys) 2] 2– and [Pb(S,N,O-Cys)(S-HCys)] – complexes with averagemore » Pb–(N/O) and Pb–S distances of 2.42 ± 0.04 and 2.64 ± 0.04 Å, respectively, was found to dominate. At high concentration of free cysteinate (>0.7 M), a significant amount converts to the trithiolate [Pb(S,N-Cys)(S-HCys) 2] 2–, including a minor amount of a PbS 3-coordinated [Pb(S-HCys) 3] – complex. The coordination mode was evaluated by fitting linear combinations of EXAFS oscillations to the experimental spectra and by examining the 207Pb NMR signals in the chemical shift range δ Pb = 2006–2507 ppm, which became increasingly deshielded with increasing free cysteinate concentration. One-pulse magic-angle-spinning (MAS) 207Pb NMR spectra of crystalline Pb(aet) 2 (Haet = 2-aminoethanethiol or cysteamine) with PbS 2N 2 coordination were measured for comparison (δ iso = 2105 ppm). The UV–vis spectra displayed absorption maxima at 298–300 nm (S – → Pb II charge transfer) for the dithiolate PbS 2N(N/O) species; with increasing ligand excess, a shoulder appeared at ~330 nm for the trithiolate PbS 3N and PbS 3 (minor) complexes. Finally, the results provide spectroscopic fingerprints for structural models for lead(II) coordination modes to proteins and enzymes.« less

  5. Long-term corrosion of a Ga-containing restorative material.

    PubMed

    Sarkar, N K; Moiseyeva, R; Berzins, D W; Osborne, J W

    2000-03-01

    The aim was to simulate and characterize the long-term corrosion of a Ga-containing alloy (Galloy, SDI). To induce corrosion, cylindrical specimens, 8 x 4 mm, of the material were subject to potentiostatic polarization at -0.1 V (SCE) in a phosphated buffered saline (PBS) solution at 20 degrees C for d. The current-time transients during polarization were recorded and the corresponding anodic charge, Q, was calculated. Parallel potentiostatic corrosion tests in a Cl-free PBS solution were also conducted to demonstrate the significance of the Cl- ion in corrosion. In addition, potentiodynamic anodic polarization tests were performed to characterize the overall corrosion behavior of the alloy in both electrolytes. The external and internal corroded layers, formed during potentiostatic corrosion in PBS, were measured by optical microscopy. SEM and EDXA were used to characterize the morphology and composition of the potentiostatically polarized surfaces. Galloy was passive in Cl-free PBS. The Cl- ion in PBS destroyed passivity and initiated a "dissolution-precipitation" type reaction during potentiostatic corrosion. The latter led to circumferential internal corrosion and growth of a layer of external corrosion products. The thickness of the internal and external corrosion layers was 0.77 +/- 0.07 and 0.86 +/- 0.37 mm, respectively. The Q value (89.3 +/- 13.7 C/cm2) in PBS was about two orders of magnitude higher than that (0.66 +/- 0.24 C/cm2) in Cl-free PBS. The corrosion products contained Sn, Ga, In, Cu, O and Cl. Massive internal and external corrosion in a Cl-containing medium as in saliva, accumulation of corrosion products at the cavity wall, and the consequent stress build-up contribute to post-operative pain, tooth straining, marginal breakdown and fractured teeth reported with the clinical use of Galloy.

  6. Search for Spin Filtering By Electron Tunneling Through Ferromagnetic EuS Barriers in Pbs

    NASA Technical Reports Server (NTRS)

    Figielski, T.; Morawski, A.; Wosinski, T.; Wrotek, S.; Makosa, A.; Lusakowska, E.; Story, T.; Sipatov, A. Yu.; Szczerbakow, A.; Grasza, K.; hide

    2002-01-01

    Perpendicular transport through single- and double-barrier heterostructures consisting of ferromagnetic EuS layers embedded into PbS matrix was investigated. Manifestations of both resonant tunneling and spin filtering through EuS barrier have been observed.

  7. Deciphering the protective role of spermidine against saline-alkaline stress at physiological and proteomic levels in tomato.

    PubMed

    Zhang, Yi; Zhang, Hao; Zou, Zhi-Rong; Liu, Yi; Hu, Xiao-Hui

    2015-02-01

    In this research, the protective effect of spermidine (Spd) in mitigating saline-alkaline stress in tomato (Solanum lycopersicum L.) at physiological and proteomic levels were examined. The results showed that saline-alkaline stress induced accumulation of H2O2 and O2(-*), and increased the activities of antioxidase (SOD, CAT, and POD). Spermidine efficiently alleviated the inhibitory role of saline-alkaline on plant growth and inhibited saline-alkaline stress-induced H2O2 and O2(-*) accumulation. Proteomics investigations of the leaves of tomato seedlings, responding to a 75 mM saline-alkaline solution and 0.25 mM Spd, were performed. Maps of the proteome of leaf extracts were obtained by two-dimensional gel electrophoresis. An average of 49, 47 and 34 spots, which appeared repeatedly and that significantly altered the relative amounts of polypeptides by more than twofold, were detected for seedlings treated with saline-alkaline solution (S) compared to normal solution (CK), saline-alkaline plus spermidine (MS) compared to CK, or S versus MS, respectively. Thirty-nine of these proteins were identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry and were classified into five functional categories, including energy and metabolism, signal transduction, amino acid metabolism, protein metabolism, and stress-defense response. Proteomics analysis coupled with bioinformatics indicated that Spd treatment helps tomato seedlings combat saline-alkaline stress by modulating the defense mechanism of plants and activating cellular detoxification, which protect plants from oxidative damage induced by saline-alkaline stress. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Size-dependent optical properties of colloidal PbS quantum dots.

    PubMed

    Moreels, Iwan; Lambert, Karel; Smeets, Dries; De Muynck, David; Nollet, Tom; Martins, José C; Vanhaecke, Frank; Vantomme, André; Delerue, Christophe; Allan, Guy; Hens, Zeger

    2009-10-27

    We quantitatively investigate the size-dependent optical properties of colloidal PbS nanocrystals or quantum dots (Qdots), by combining the Qdot absorbance spectra with detailed elemental analysis of the Qdot suspensions. At high energies, the molar extinction coefficient epsilon increases with the Qdot volume d(3) and agrees with theoretical calculations using the Maxwell-Garnett effective medium theory and bulk values for the Qdot dielectric function. This demonstrates that quantum confinement has no influence on epsilon in this spectral range, and it provides an accurate method to calculate the Qdot concentration. Around the band gap, epsilon only increases with d(1.3), and values are comparable to the epsilon of PbSe Qdots. The data are related to the oscillator strength f(if) of the band gap transition and results agree well with theoretical tight-binding calculations, predicting a linear dependence of f(if) on d. For both PbS and PbSe Qdots, the exciton lifetime tau is calculated from f(if). We find values ranging between 1 and 3 mus, in agreement with experimental literature data from time-resolved luminescence spectroscopy. Our results provide a thorough general framework to calculate and understand the optical properties of suspended colloidal quantum dots. Most importantly, it highlights the significance of the local field factor in these systems.

  9. Responses of spinach to salinity and nutrient deficiency in growth, physiology and nutritional value

    USDA-ARS?s Scientific Manuscript database

    Salinity and nutrient depleted soil are major constraints to crop production, especially for vegetable crops. The effects of salinity and nutrient deficiency on spinach were evaluated in sand cultures under greenhouse conditions. Plants were watered every day with Hoagland nutrition solution, depriv...

  10. In Situ Passivation for Efficient PbS Quantum Dot Solar Cells by Precursor Engineering.

    PubMed

    Wang, Yongjie; Lu, Kunyuan; Han, Lu; Liu, Zeke; Shi, Guozheng; Fang, Honghua; Chen, Si; Wu, Tian; Yang, Fan; Gu, Mengfan; Zhou, Sijie; Ling, Xufeng; Tang, Xun; Zheng, Jiawei; Loi, Maria Antonietta; Ma, Wanli

    2018-04-01

    Current efforts on lead sulfide quantum dot (PbS QD) solar cells are mostly paid to the device architecture engineering and postsynthetic surface modification, while very rare work regarding the optimization of PbS synthesis is reported. Here, PbS QDs are successfully synthesized using PbO and PbAc 2  · 3H 2 O as the lead sources. QD solar cells based on PbAc-PbS have demonstrated a high power conversion efficiency (PCE) of 10.82% (and independently certificated values of 10.62%), which is significantly higher than the PCE of 9.39% for PbO-PbS QD based ones. For the first time, systematic investigations are carried out on the effect of lead precursor engineering on the device performance. It is revealed that acetate can act as an efficient capping ligands together with oleic acid, providing better surface coverage and replace some of the harmful hydroxyl (OH) ligands during the synthesis. Then the acetate on the surface can be exchanged by iodide and lead to desired passivation. This work demonstrates that the precursor engineering has great potential in performance improvement. It is also pointed out that the initial synthesis is an often neglected but critical stage and has abundant room for optimization to further improve the quality of the resultant QDs, leading to breakthrough efficiency. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Equiosmolar Solutions of Hypertonic Saline and Mannitol Do Not Impair Blood Coagulation During Elective Intracranial Surgery.

    PubMed

    Hernández-Palazón, Joaquín; Fuentes-García, Diego; Doménech-Asensi, Paloma; Piqueras-Pérez, Claudio; Falcón-Araña, Luis; Burguillos-López, Sebastián

    2017-01-01

    The authors investigated the effect of equiosmolar, equivolemic solutions of 3% hypertonic saline (HS) and 20% mannitol on blood coagulation assessed by rotational thromboelastometry (ROTEM) and standard coagulation tests during elective craniotomy. In a prospective, randomized, double-blind trial, 40 patients undergoing elective craniotomy were randomized to receive 5 mL/kg of either 20% mannitol or 3% HS for intraoperative brain relaxation. Fibrinogen, activated partial thromboplastin time, prothrombin time, hemoglobin, hematocrit, and platelet count were simultaneously measured intraoperatively with ROTEM for EXTEM, INTEM, and FIBTEM analysis. ROTEM parameters were: clotting time (CT), clot formation time (CFT), maximum clot firmness (MCF), and α-angle. No significant differences between groups were found in ROTEM variables CT, CFT, MCF, α-angle (EXTEM and INTEM), and MCF (FIBTEM) nor standard coagulation tests. ROTEM parameters did not show changes after administration of hyperosmolar solutions relating to basal values, except for an increase of CFT EXTEM (118±28 vs. 128±26 s) and decrease of CT INTEM (160±18 vs. 148±15 s) with values within normal range. Significant decreases from baseline levels were observed for hematocrit (-7%), platelet count (-10%), and fibrinogen (-13%) after HS infusion, and hematocrit (-9%), platelet count (-13%), and fibrinogen (-9%) after mannitol infusion, but remaining normal. The use of 5 mL/kg of equiosmolar solutions of 3% HS and 20% mannitol applied to reach a brain relaxation during elective craniotomy does not induce coagulation impairment as evidenced by ROTEM and standard coagulation tests.

  12. Ultrastructure in frozen/etched saline solutions: on the internal cleansing of ice.

    PubMed

    Menger, Fredric M; Galloway, Ashley L; Chlebowski, Mary E; Apkarian, Robert P

    2004-05-19

    Seawater, with its 3.5% salt content, freezes into hexagonal ice (Ih) that encloses concentrated brine within its matrix. When unsubmerged sea ice reaches a certain height and temperature, the brine drains downward through narrow channels. This mechanism was now modeled by frozen 2-3.5% saline as investigated by cryo-etch high-resolution secondary electron microscopy. Thus, saline was either plunge-frozen in liquid ethane at -183 degrees C or else high-pressure frozen to -105 degrees C in 5-6 ms. Ice from a freshly exposed surface was then subjected to a high-vacuum sublimation ("etching"), a procedure that removes pure bulk ice in preference to ice from frozen hydrated salt. After chromium-coating the etched surface with a 2-nm film, the sample was examined by cryo-HRSEM. Granular icy "fences" were seen surrounding empty areas where amorphous ice had originally resided. Since the fences, about 1-2 mum high, survived the etching, it is likely that they consist of frozen brine. The presence of such fences suggests that, during freezing, saline can purge itself of salt with remarkable speed (5-6 ms). Alternatively, channels (perhaps routed around submicroscopic crystallites of cubic ice (Ic) embedded in the amorphous ice at -105 degrees C) can guide the migration of salt to the periphery of ice patches. Macromolecules fail to form fences because they diffuse too slowly or because they are too large to pass through the channels.

  13. Spectroscopic study of Pbs nano-structured layer prepared by Pld utilized as a Hall-effect magnetic sensor

    NASA Astrophysics Data System (ADS)

    Atwa, D. M.; Aboulfotoh, N.; El-magd, A. Abo; Badr, Y.

    2013-10-01

    Lead sulfide (PbS) nano-structured films have been grown on quartz substrates using PLD technique. The deposited films were characterized by several structural techniques, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Selected-area electron diffraction patterns (SAED). The results prove the formation of cubic phase of PbS nanocrystals. Elemental analysis of the deposited films compared to the bulk target was obtained via laser induced fluorescence of the produced plasma particles and the energy dispersive X-ray "EDX" technique. The Hall coefficient measurements indicate an efficient performance of the deposited films as a magnetic sensor.

  14. Comparison of 7.2% hypertonic saline - 6% hydroxyethyl starch solution and 6% hydroxyethyl starch solution after the induction of anesthesia in patients undergoing elective neurosurgical procedures.

    PubMed

    Shao, Liujiazi; Wang, Baoguo; Wang, Shuangyan; Mu, Feng; Gu, Ke

    2013-01-01

    The ideal solution for fluid management during neurosurgical procedures remains controversial. The aim of this study was to compare the effects of a 7.2% hypertonic saline - 6% hydroxyethyl starch (HS-HES) solution and a 6% hydroxyethyl starch (HES) solution on clinical, hemodynamic and laboratory variables during elective neurosurgical procedures. Forty patients scheduled for elective neurosurgical procedures were randomly assigned to the HS-HES group orthe HES group. Afterthe induction of anesthesia, patients in the HS-HES group received 250 mL of HS-HES (500 mL/h), whereas the patients in the HES group received 1,000 mL of HES (1000 mL/h). The monitored variables included clinical, hemodynamic and laboratory parameters. Chictr.org: ChiCTR-TRC-12002357 The patients who received the HS-HES solution had a significant decrease in the intraoperative total fluid input (p<0.01), the volume of Ringer's solution required (p<0.05), the fluid balance (p<0.01) and their dural tension scores (p<0.05). The total urine output, blood loss, bleeding severity scores, operation duration and hemodynamic variables were similar in both groups (p>0.05). Moreover, compared with the HES group, the HS-HES group had significantly higher plasma concentrations of sodium and chloride, increasing the osmolality (p<0.01). Our results suggest that HS-HES reduced the volume of intraoperative fluid required to maintain the patients undergoing surgery and led to a decrease in the intraoperative fluid balance. Moreover, HS-HES improved the dural tension scores and provided satisfactory brain relaxation. Our results indicate that HS-HES may represent a new avenue for volume therapy during elective neurosurgical procedures.

  15. In-Vitro Corrosion Studies of Bioabsorbable Alloys

    NASA Astrophysics Data System (ADS)

    Gill, P.; Munroe, N.

    Magnesium alloys have inspired a significant amount of attention from researchers all over the world for cardiovascular and orthopedic applications due to their light weight, mechanical integrity and degradation behavior. In this investigation, cast manufactured binary, ternary and quaternary magnesium alloys were studied for their degradation behavior by potentiodynamic polarization tests in phosphate buffer saline solution (PBS) and PBS containing amino acids (cysteine, C and tryptophan, W) at 37 °C. Electrochemical impedance spectroscopy (EIS) tests were performed to determine the charge transfer resistance and immersion tests were performed to assess corrosion rate and hydrogen evolution from the alloys. Furthermore, the surface morphology and surface chemistry of the alloys were observed by scanning electron microscopy (SEM) and X-ray diffraction (XRD).

  16. AFM investigation and optical band gap study of chemically deposited PbS thin films

    NASA Astrophysics Data System (ADS)

    Zaman, S.; Mansoor, M.; Abubakar; Asim, M. M.

    2016-08-01

    The interest into deposition of nanocrystalline PbS thin films, the potential of designing and tailoring both the topographical features and the band gap energy (Eg) by controlling growth parameters, has significant technological importance. Nanocrystalline thin films of lead sulfide were grown onto glass substrates by chemical bath deposition (CBD) method. The experiments were carried out by varying deposition temperature. We report on the modification of structural and optical properties as a function of deposition temperature. The morphological changes of the films were analyzed by using SEM and AFM. AFM was also used to calculate average roughness of the films. XRD spectra indicated preferred growth of cubic phase of PbS films in (200) direction with increasing deposition time. Optical properties have been studied by UV-Spectrophotometer. From the diffused reflectance spectra we have calculated the optical Eg shift from 0.649-0.636 eV with increasing deposition time.

  17. Organic matter and salinity modify cadmium soil (phyto)availability.

    PubMed

    Filipović, Lana; Romić, Marija; Romić, Davor; Filipović, Vilim; Ondrašek, Gabrijel

    2018-01-01

    Although Cd availability depends on its total concentration in soil, it is ultimately defined by the processes which control its mobility, transformations and soil solution speciation. Cd mobility between different soil fractions can be significantly affected by certain pedovariables such as soil organic matter (SOM; over formation of metal-organic complexes) and/or soil salinity (over formation of metal-inorganic complexes). Phytoavailable Cd fraction may be described as the proportion of the available Cd in soil which is actually accessible by roots and available for plant uptake. Therefore, in a greenhouse pot experiment Cd availability was observed in the rhizosphere of faba bean exposed to different levels of SOM, NaCl salinity (50 and 100mM) and Cd contamination (5 and 10mgkg -1 ). Cd availability in soil does not linearly follow its total concentration. Still, increasing soil Cd concentration may lead to increased Cd phytoavailability if the proportion of Cd 2+ pool in soil solution is enhanced. Reduced Cd (phyto)availability by raised SOM was found, along with increased proportion of Cd-DOC complexes in soil solution. Data suggest decreased Cd soil (phyto)availability with the application of salts. NaCl salinity affected Cd speciation in soil solution by promoting the formation of CdCl n 2-n complexes. Results possibly suggest that increased Cd mobility in soil does not result in its increased availability if soil adsorption capacity for Cd has not been exceeded. Accordingly, chloro-complex possibly operated just as a Cd carrier between different soil fractions and resulted only in transfer between solid phases and not in increased (phyto)availability. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Effects of Salinity and Confining Pressure on Hydration-Induced Fracture Propagation and Permeability of Mancos Shale

    NASA Astrophysics Data System (ADS)

    Zhang, Shifeng; Sheng, James J.

    2017-11-01

    Low-salinity water imbibition was considered an enhanced recovery method in shale oil/gas reservoirs due to the resulting hydration-induced fractures, as observed at ambient conditions. To study the effect of confining pressure and salinity on hydration-induced fractures, time-elapsed computerized tomography (CT) was used to obtain cross-sectional images of shale cores. Based on the CT data of these cross-sectional images, cut faces parallel to the core axial in the middle of the core and 3D fracture images were also reconstructed. To study the effects of confining pressure and salinity on shale pore fluid flowing, shale permeability was measured with Nitrogen (N2), distilled water, 4% KCl solution, and 8% KCl solution. With confining pressures increased to 2 MPa or more, either in distilled water or in KCl solutions of different salinities, fractures were observed to close instead to propagate at the end of the tests. The intrinsic permeabilities of #1 and #2 Mancos shale cores were 60.0 and 7000 nD, respectively. When tested with distilled water, the permeability of #1 shale sample with 20.0 MPa confining pressure loaded, and #2 shale sample with 2.5 MPa confining pressure loaded, decreased to 0.45 and 15 nD, respectively. Using KCl can partly mitigate shale permeability degradation. Compared to 4% KCl, 8% KCl can decrease more permeability damage. From this point of view, high salinity KCl solution should be required for the water-based fracturing fluid.

  19. Genetic variation and plasticity of Plantago coronopus under saline conditions

    NASA Astrophysics Data System (ADS)

    Smekens, Marret J.; van Tienderen, Peter H.

    2001-08-01

    Phenotypic plasticity may allow organisms to cope with variation in the environmental conditions they encounter in their natural habitats. Salt adaptation appears to be an excellent example of such a plastic response. Many plant species accumulate organic solutes in response to saline conditions. Comparative and molecular studies suggest that this is an adaptation to osmotic stress. However, evidence relating the physiological responses to fitness parameters is rare and requires assessing the potential costs and benefits of plasticity. We studied the response of thirty families derived from plants collected in three populations of Plantago coronopus in a greenhouse experiment under saline and non-saline conditions. We indeed found a positive selection gradient for the sorbitol percentage under saline conditions: plant families with a higher proportion of sorbitol produced more spikes. No effects of sorbitol on fitness parameters were found under non-saline conditions. Populations also differed genetically in leaf number, spike number, sorbitol concentration and percentages of different soluble sugars. Salt treatment led to a reduction of vegetative biomass and spike production but increased leaf dry matter percentage and leaf thickness. Both under saline and non-saline conditions there was a negative trade-off between vegetative growth and reproduction. Families with a high plasticity in leaf thickness had a lower total spike length under non-saline conditions. This would imply that natural selection under predominantly non-saline conditions would lead to a decrease in the ability to change leaf morphology in response to exposure to salt. All other tests revealed no indication for any costs of plasticity to saline conditions.

  20. Preparation of non-aggregating aqueous fullerenes in highly saline solutions with a biocompatible non-ionic polymer

    NASA Astrophysics Data System (ADS)

    Aich, Nirupam; Boateng, Linkel K.; Flora, Joseph R. V.; Saleh, Navid B.

    2013-10-01

    Size-tunable stable aqueous fullerenes were prepared with different concentrations of biocompatible block-copolymer pluronic (PA) F-127, ranging from 0.001% to 1% (w/v). Size uniformity increased with the increase in PA concentration, yielding optimum 58.8 ± 5.6 and 61.8 ± 5.6 nm nC60s and nC70s, respectively (0.10%w/v PA), as observed using a dynamic light scattering technique. Fullerene aqueous suspensions also manifested enhanced stability in saline solution, Dulbecco’s modified Eagle medium (DMEM), and Roswell Park Memorial Institute (RPMI) culture medium. Transmission electron microscopy was performed to elaborate on the morphology and size specificity of fullerene clusters. Physicochemical characterizations of the suspended fullerenes were performed through UV-vis spectroscopy and electrophoretic mobility measurements. PA molecules showed size restriction by encasement, as observed via molecular dynamics simulations. Such solubilization with controllable size and non-aggregating behavior can facilitate application enhancement and mechanistic environmental and toxicological studies of size-specific fullerenes.

  1. Effects of salinity and flooding on seedlings of cabbage palm (Sabal palmetto).

    PubMed

    Perry, L; Williams, K

    1996-03-01

    Sabal palmetto (Walt.) Lodd. ex Schultes (cabbage palm) dominates the coastal limit of many forests in North Florida and Georgia, United States. Changes in saltwater flooding due to sea level rise have been credicted with pushing the coastal limit of cabbage palms inland, eliminating regeneration before causing death of mature trees. Localized freshwater discharge along the coast causes different forest stands to experience tidal flooding with waters that differ in salinity. To elucidate the effect of such variation on regeneration failure under tidal flooding, we examined relative effects of flooding and salinity on the performance of cabbage palm seedlings. We examined the relationship between seedling establishment and degree of tidal inundation in the field, compared the ability of seedlings to withstand tidal flooding at two coastal sites that differed in tidal water salinity, and investigated the physiological responses of cabbage palm seedlings to salinity and flooding in a factorial greenhouse experiment. Seedling survival was inversely correlated with depth and frequency of tidal flooding. Survival of seedlings at a coastal site flooded by waters low in salinity [c. 3 parts per thousand (ppt)] was greater than that at a site flooded by waters higher in salinity (up to 23 ppt). Greenhouse experiments revealed that leaves of seedlings in pots flushed twice daily with salt solutions of 0 ppt and 8 ppt exhibited little difference in midmorning net CO 2 assimilation rates; those flushed with solutions of 15 ppt and 22 ppt, in contrast, had such low rates that they could not be detected. Net CO 2 assimilation rates also declined with increasing salinity for seedlings in pots that were continuously inundated. Continuous root zone inundation appeared to ameliorate effects of salinity on photosynthesis, presumably due to increased salt concentrations and possibly water deficits in periodically flushed pots. Such problems associated with periodic flushing by salt

  2. A comparison of hydroxyl radical and hydrogen peroxide generation in ambient particle extracts and laboratory metal solutions

    NASA Astrophysics Data System (ADS)

    Shen, Huiyun; Anastasio, Cort

    2012-01-01

    Generation of reactive oxygen species (ROS) - including superoxide ( rad O 2-), hydrogen peroxide (HOOH), and hydroxyl radical ( rad OH) - has been suggested as one mechanism underlying the adverse health effects caused by ambient particulate matter (PM). In this study we compare HOOH and rad OH production from fine and coarse PM collected at an urban (Fresno) and rural (Westside) site in the San Joaquin Valley (SJV) of California, as well as from laboratory solutions containing dissolved copper or iron. Samples were extracted in a cell-free, phosphate-buffered saline (PBS) solution containing 50 μM ascorbate (Asc). In our laboratory solutions we find that Cu is a potent source of both HOOH and rad OH, with approximately 90% of the electrons that can be donated from Asc ending up in HOOH and rad OH after 4 h. In contrast, in Fe solutions there is no measurable HOOH and only a modest production of rad OH. Soluble Cu in the SJV PM samples is also a dominant source of HOOH and rad OH. In both laboratory copper solutions and extracts of ambient particles we find much more production of HOOH compared to rad OH: e.g., HOOH generation is approximately 30-60 times faster than rad OH generation. The formation of HOOH and rad OH are positively correlated, with roughly 3% and 8% of HOOH converted to rad OH after 4 and 24 h of extraction, respectively. Although the SJV PM produce much more HOOH than rad OH, since rad OH is a much stronger oxidant it is unclear which species might be more important for oxidant-mediated toxicity from PM inhalation.

  3. A Comparison of Hydroxyl Radical and Hydrogen Peroxide Generation in Ambient Particle Extracts and Laboratory Metal Solutions

    PubMed Central

    Shen, Huiyun; Anastasio, Cort

    2011-01-01

    Generation of reactive oxygen species (ROS) – including superoxide (•O2−), hydrogen peroxide (HOOH), and hydroxyl radical (•OH) – has been suggested as one mechanism underlying the adverse health effects caused by ambient particulate matter (PM). In this study we compare HOOH and •OH production from fine and coarse PM collected at an urban (Fresno) and rural (Westside) site in the San Joaquin Valley (SJV) of California, as well as from laboratory solutions containing dissolved copper or iron. Samples were extracted in a cell-free, phosphate-buffered saline (PBS) solution containing 50 μM ascorbate (Asc). In our laboratory solutions we find that Cu is a potent source of both HOOH and •OH, with approximately 90% of the electrons that can be donated from Asc ending up in HOOH and •OH after 4 h. In contrast, in Fe solutions there is no measurable HOOH and only a modest production of •OH. Soluble Cu in the SJV PM samples is also a dominant source of HOOH and •OH. In both laboratory copper solutions and extracts of ambient particles we find much more production of HOOH compared to •OH: e.g., HOOH generation is approximately 30 – 60 times faster than •OH generation. The formation of HOOH and •OH are positively correlated, with roughly 3 % and 8 % of HOOH converted to •OH after 4 and 24 hr of extraction, respectively. Although the SJV PM produce much more HOOH than •OH, since •OH is a much stronger oxidant it is unclear which species might be more important for oxidant-mediated toxicity from PM inhalation. PMID:22267949

  4. Self-organization of colloidal PbS quantum dots into highly ordered superlattices.

    PubMed

    Baranov, Alexander V; Ushakova, Elena V; Golubkov, Valery V; Litvin, Aleksandr P; Parfenov, Peter S; Fedorov, Anatoly V; Berwick, Kevin

    2015-01-13

    X-ray structural analysis, together with steady-state and transient optical spectroscopy, is used for studying the morphology and optical properties of quantum dot superlattices (QDSLs) formed on glass substrates by the self-organization of PbS quantum dots with a variety of surface ligands. The diameter of the PbS QDs varies from 2.8 to 8.9 nm. The QDSL's period is proportional to the dot diameter, increasing slightly with dot size due to the increase in ligand layer thickness. Removal of the ligands has a number of effects on the morphology of QDSLs formed from the dots of different sizes: for small QDs the reduction in the amount of ligands obstructs the self-organization process, impairing the ordering of the QDSLs, while for large QDs the ordering of the superlattice structure is improved, with an interdot distance as low as 0.4 nm allowing rapid charge carrier transport through the QDSLs. QDSL formation does not induce significant changes to the absorption and photoluminescence spectra of the QDs. However, the luminescence decay time is reduced dramatically, due to the appearance of nonradiative relaxation channels.

  5. [ARTCEREB irrigation and perfusion solution for cerebrospinal surgery: pharmacological assessment using human astrocytes exposed to test solutions].

    PubMed

    Nishimura, Masuhiro; Doi, Kazuhisa; Enomoto, Riyo; Lee, Eibai; Naito, Shinsaku; Yamauchi, Aiko

    2009-09-01

    ARTCEREB irrigation and perfusion solution (Artcereb) is a preparation intended for the irrigation and perfusion of the cerebral ventricles, and it is therefore important to evaluate the effects of Artcereb on brain cells. In vitro assessment of the effects of Artcereb in cell cultures of human fetal astrocytes was conducted in comparison with normal saline and lactated Ringer's solution. The effects of exposure to Artcereb were evaluated based on microscopic images of the mitochondria stained with rhodamine 123. The effects of exposure to Artcereb on cell function were also evaluated by quantitative analysis of mitochondrial activity based on rhodamine 123 and (3)H-thymidine incorporation. Morphological changes in nuclear structure were also evaluated. The results of the present study showed that cell function in cell cultures of human astrocytes was relatively unaffected by exposure to Artcereb as compared with normal saline or lactated Ringer's solution, suggesting that Artcereb has less effect on brain cells than normal saline or lactated Ringer's solution when used for the irrigation or perfusion of the cerebral ventricles.

  6. Impact Assessment of Salinization Affected Soil on Greenhouse Crops using SALTMED

    NASA Astrophysics Data System (ADS)

    Pappa, Polyxeni; Daliakopoulos, Ioannis; Tsanis, Ioannis; Varouchakis, Emmanouil

    2015-04-01

    Here we assess the effects of soil salinization on greenhouse crops and the potential benefits of rainwater harvesting as a soil amelioration technology. The study deals with the following scenarios: (a) variation of irrigation water salinity from 3,000 μS/cm to 500 μS/cm through mixing with rainwater, (b) crop substitution for increased tolerance and (c) climatic variability to account for the impact of climate change. In order to draw meaningful conclusions, a model that takes into account vegetation interaction, soil, irrigation water and climate variables is required. The SALTMED model is a reliable and tested physical process model that simulates evapotranspiration, plant water uptake, water and solute transport to estimate crop yield and biomass production under all irrigation systems. SALTMED is tested with the above scenarios in the RECARE FP7 Project Case Study of Timpaki, in the Island of Crete, Greece. Simulations are conducted for typical cultivations of Solanum lycopersicum, Capsicum anuumm and Solanum melongena. Preliminary results indicate the optimal combination from a set of solutions concerning the soil and water parameters can be beneficial against the salinization threat. Future research includes the validation of the results with field experiments. Keywords: salinization, greenhouse, tomato, SALTMED, rainwater, RECARE

  7. Analytical Solution for Interface Flow to a Sink With an Upconed Saline Water Lens: Strack's Regimes Revisited

    NASA Astrophysics Data System (ADS)

    Kacimov, A. R.; Obnosov, Y. V.

    2018-01-01

    A study is made of a steady, two-dimensional groundwater flow with a horizontal well (drain), which pumps out freshwater from an aquifer sandwiched between a horizontal bedrock and ponded soil surface, and containing a lens-shaped static volume of a heavier saline water (DNAPL-dense nonaqueous phase liquid) as a free surface. For flow toward a line sink, an explicit analytical solution is obtained by a conformal mapping of the hexagon in the complex potential plane onto a reference plane and the Keldysh-Sedov integral representation of a mixed boundary-value problem for a complex physical coordinate. The interface is found as a function of the pumping rate, the well locus, the ratio of liquid densities, and the hydraulic heads at the soil surface and in the well. The shape with two inflexion points and fronts varies from a small-thickness bedrock-spread pancake to a critical curvilinear triangle, which cusps toward the sink. The problem is mathematically solvable in a relatively narrow band of geometric and hydraulic parameters. A similar analytic solution for a static heavy bubble confined by a closed-curve interface (no contact with the bedrock) is outlined as an illustration of the method to solve a mixed boundary-value problem.

  8. Comparison of 7.2% hypertonic saline - 6% hydroxyethyl starch solution and 6% hydroxyethyl starch solution after the induction of anesthesia in patients undergoing elective neurosurgical procedures

    PubMed Central

    Shao, Liujiazi; Wang, Baoguo; Wang, Shuangyan; Mu, Feng; Gu, Ke

    2013-01-01

    OBJECTIVE: The ideal solution for fluid management during neurosurgical procedures remains controversial. The aim of this study was to compare the effects of a 7.2% hypertonic saline - 6% hydroxyethyl starch (HS-HES) solution and a 6% hydroxyethyl starch (HES) solution on clinical, hemodynamic and laboratory variables during elective neurosurgical procedures. METHODS: Forty patients scheduled for elective neurosurgical procedures were randomly assigned to the HS-HES group or the HES group. After the induction of anesthesia, patients in the HS-HES group received 250 mL of HS-HES (500 mL/h), whereas the patients in the HES group received 1,000 mL of HES (1000 mL/h). The monitored variables included clinical, hemodynamic and laboratory parameters. Chictr.org: ChiCTR-TRC-12002357 RESULTS: The patients who received the HS-HES solution had a significant decrease in the intraoperative total fluid input (p<0.01), the volume of Ringer's solution required (p<0.05), the fluid balance (p<0.01) and their dural tension scores (p<0.05). The total urine output, blood loss, bleeding severity scores, operation duration and hemodynamic variables were similar in both groups (p>0.05). Moreover, compared with the HES group, the HS-HES group had significantly higher plasma concentrations of sodium and chloride, increasing the osmolality (p<0.01). CONCLUSION: Our results suggest that HS-HES reduced the volume of intraoperative fluid required to maintain the patients undergoing surgery and led to a decrease in the intraoperative fluid balance. Moreover, HS-HES improved the dural tension scores and provided satisfactory brain relaxation. Our results indicate that HS-HES may represent a new avenue for volume therapy during elective neurosurgical procedures. PMID:23644851

  9. [Preliminary establishment of cytological examination and the normal reference values for hypertonic saline solution-induced sputum of healthy children in Guangzhou].

    PubMed

    Chen, De-hui; Zhong, Guo-yu; Luo, Wei; Chen, Qiao-li; Chen, Ru-chong; Lin, Yu-neng; Pan, Xiao-an; Li, Jin-ying; Wu, Shang-zhi; Lai, Ke-fang; Zhong, Nan-shan

    2012-07-01

    To establish the method of cytological examination and the normal reference values for hypertonic saline solution-induced sputum of healthy children (age range from 5 to 15 years) with physical examination in Guangzhou. A total of 352 children, 5 to 15 years old, were enrolled from primary school and middle school in Guangzhou from January to December, 2010. All subjects completed a standardized questionnaire on the presence of respiratory, allergic symptoms and family history, the medical history and the physical examination was performed by doctors, lung function (forced expiratory volume at 1 s in predicted normal, FEV(1)%) was determined. There were 266 healthy children (137 males, 129 females) who were selected and undergone hypertonic saline solution induction of sputum, and cytological examination was performed. Hypertonic saline (5%) was nebulized and inhaled for 15 - 30 min. No expectoration within 30 min was defined as failure, and the procedure was terminated. The part of opaque and higher density sputum samples was detected by cytology. The proportion of neutrophils, lymphocytes, eosinophils, macrophages and monocytes was calculated. This study was approved by the institutional Ethics Review Committee of First Affiliated Hospital of Guangzhou Medical College. Informed consent was obtained from the legal guardians of all participants following a detailed description of the purpose and potential benefits of the study. There were 175 subjects' induced sputum specimens (175/266, 65.8%), non-qualified sputum samples were obtained from 16 of the subjects. The proportions of median (IQR) of lymphocytes were 0.012 (0.020), 95%CI were ranged from 0.015 to 0.022; neutrophils 0.207 (0.330), 95%CI 0.266 - 0.356 macrophages 0.761 (0.327), 95%CI 0.607 - 0.699; eosinophils 0.004 (0.019), 95%CI 0.013 - 0.022. There were no significant differences in proportions of cytological findings of female or male, different age groups and second-hand smoking or not (all P > 0

  10. Self-assembled phytosterol-fructose-chitosan nanoparticles as a carrier of anticancer drug.

    PubMed

    Qiu, Yeyan; Zhu, Jun; Wang, Jianting; Gong, Renmin; Zheng, Mingming; Huang, Fenghong

    2013-08-01

    Self-assembled nanoparticles were synthesized from water-soluble fructose-chitosan, substituted by succinyl linkages with phytosterols as hydrophobic moieties for self-assembly. The physicochemical properties of the prepared self-assembled nanoparticles were characterized by Fourier transform infrared spectroscopy, fluorescence spectroscopy, and transmission electron microscopy. Doxorubicin (DOX), as a model anticancer drug, was physically entrapped inside prepared self-assembled nanoparticles by the dialysis method. With increasing initial levels of the drug, the drug loading content increased, but the encapsulation efficiency decreased. The release profiles in vitro demonstrated that the DOX showed slow sustained released over 48 h, and the release rate in phosphate buffered saline (PBS) solution (pH 7.4) was much slower than in PBS solution (pH 5.5 and pH 6.5), indicating the prepared self-assembled nanoparticles had the potential to be used as a carrier for targeted delivery of hydrophobic anticancer drugs with declined cytotoxicity to normal tissues.

  11. High temperature thermoelectric properties of rock-salt structure PbS

    DOE PAGES

    Parker, David S.; Singh, David J.

    2013-12-18

    We present an analysis of the high temperature transport properties of rock-salt structure PbS, a sister compound to the better studied lead chalcogenides PbSe and PbTe. In this study, we find thermopower magnitudes exceeding 200 V/K in a wide doping range for temperatures of 800 K and above. Based on these calculations, and an analysis of recent experimental work we find that this material has a potential for high thermoelectric performance. Also, we find favorable mechanical properties, based on an analysis of published data.

  12. Reexamining ultrafiltration and solute transport in groundwater

    NASA Astrophysics Data System (ADS)

    Neuzil, C. E.; Person, Mark

    2017-06-01

    Geologic ultrafiltration—slowing of solutes with respect to flowing groundwater—poses a conundrum: it is consistently observed experimentally in clay-rich lithologies, but has been difficult to identify in subsurface data. Resolving this could be important for clarifying clay and shale transport properties at large scales as well as interpreting solute and isotope patterns for applications ranging from nuclear waste repository siting to understanding fluid transport in tectonically active environments. Simulations of one-dimensional NaCl transport across ultrafiltering clay membrane strata constrained by emerging data on geologic membrane properties showed different ultrafiltration effects than have often been envisioned. In relatively high-permeability advection-dominated regimes, salinity increases occurred mostly within membrane units while their effluent salinity initially fell and then rose to match solute delivery. In relatively low-permeability diffusion-dominated regimes, salinity peaked at the membrane upstream boundary and effluent salinity remained low. In both scenarios, however, only modest salinity changes (up to ˜3 g L-1) occurred because of self-limiting tendencies; membrane efficiency declines as salinity rises, and although sediment compaction increases efficiency, it is also decreases permeability and allows diffusive transport to dominate. It appears difficult for ultrafiltration to generate brines as speculated, but widespread and less extreme ultrafiltration effects in the subsurface could be unrecognized. Conditions needed for ultrafiltration are present in settings that include topographically-driven flow systems, confined aquifer systems subjected to injection or withdrawal, compacting basins, and accretionary complexes.

  13. Reexamining ultrafiltration and solute transport in groundwater

    USGS Publications Warehouse

    Neuzil, Christopher E.; Person, Mark

    2017-01-01

    Geologic ultrafiltration—slowing of solutes with respect to flowing groundwater—poses a conundrum: it is consistently observed experimentally in clay-rich lithologies, but has been difficult to identify in subsurface data. Resolving this could be important for clarifying clay and shale transport properties at large scales as well as interpreting solute and isotope patterns for applications ranging from nuclear waste repository siting to understanding fluid transport in tectonically active environments. Simulations of one-dimensional NaCl transport across ultrafiltering clay membrane strata constrained by emerging data on geologic membrane properties showed different ultrafiltration effects than have often been envisioned. In relatively high-permeability advection-dominated regimes, salinity increases occurred mostly within membrane units while their effluent salinity initially fell and then rose to match solute delivery. In relatively low-permeability diffusion-dominated regimes, salinity peaked at the membrane upstream boundary and effluent salinity remained low. In both scenarios, however, only modest salinity changes (up to ∼3 g L−1) occurred because of self-limiting tendencies; membrane efficiency declines as salinity rises, and although sediment compaction increases efficiency, it is also decreases permeability and allows diffusive transport to dominate. It appears difficult for ultrafiltration to generate brines as speculated, but widespread and less extreme ultrafiltration effects in the subsurface could be unrecognized. Conditions needed for ultrafiltration are present in settings that include topographically-driven flow systems, confined aquifer systems subjected to injection or withdrawal, compacting basins, and accretionary complexes.

  14. Tuning light emission of PbS nanocrystals from infrared to visible range by cation exchange

    PubMed Central

    Binetti, Enrico; Striccoli, Marinella; Sibillano, Teresa; Giannini, Cinzia; Brescia, Rosaria; Falqui, Andrea; Comparelli, Roberto; Corricelli, Michela; Tommasi, Raffaele; Agostiano, Angela; Curri, M Lucia

    2015-01-01

    Colloidal semiconductor nanocrystals, with intense and sharp-line emission between red and near-infrared spectral regions, are of great interest for optoelectronic and bio-imaging applications. The growth of an inorganic passivation layer on nanocrystal surfaces is a common strategy to improve their chemical and optical stability and their photoluminescence quantum yield. In particular, cation exchange is a suitable approach for shell growth at the expense of the nanocrystal core size. Here, the cation exchange process is used to promote the formation of a CdS passivation layer on the surface of very small PbS nanocrystals (2.3 nm in diameter), blue shifting their optical spectra and yielding luminescent and stable nanostructures emitting in the range of 700–850 nm. Structural, morphological and compositional investigation confirms the nanocrystal size contraction after the cation-exchange process, while the PbS rock-salt crystalline phase is retained. Absorption and photoluminescence spectroscopy demonstrate the growth of a passivation layer with a decrease of the PbS core size, as inferred by the blue-shift of the excitonic peaks. The surface passivation strongly increases the photoluminescence intensity and the excited state lifetime. In addition, the nanocrystals reveal increased stability against oxidation over time. Thanks to their absorption and emission spectral range and the slow recombination dynamics, such highly luminescent nano-objects can find interesting applications in sensitized photovoltaic cells and light-emitting devices. PMID:27877842

  15. Graft preservation solutions in cardiovascular surgery.

    PubMed

    Winkler, Bernhard; Reineke, David; Heinisch, Paul Philip; Schönhoff, Florian; Huber, Christoph; Kadner, Alexander; Englberger, Lars; Carrel, Thierry

    2016-08-01

    Vein grafts are still the most commonly used graft material in cardiovascular surgery and much effort has been spent in recent years on investigating the optimal harvesting technique. One other related topic of similar importance remained more or less an incidental one. The storage solutions of vein grafts following procurement and prior to implantation are, despite their assumed impact, a relatively neglected theme. There is no doubt that the endothelium plays a key role in long-term patency of vein grafts, but the effects of the different storage solutions on the endothelium remain unclear : In a review of the literature, we could find 20 specific papers that addressed the question, of which the currently available preservation solutions are superior, harmless, damaging or ineffective. The focus lies on saline and autologous whole blood. Besides these two storage media, novel or alternative solutions have been investigated with surprising findings. In addition, a few words will be spent on potential alternatives and novel solutions on the market. As there is currently no randomized clinical trial regarding saline versus autologous whole blood available, this review compares all previous studies and methods of analysis to provide a certain level of evidence on this topic. In summary, saline has negative effects on the endothelial layers and therefore may compromise graft patency. Related factors, such as distension pressure, may outbalance the initial benefit of autologous whole blood or storage solutions and intensify the harmful effects of warm saline. In addition, there is no uniform consent on the superiority of autologous whole blood for vein graft storage. This may open the door to alternatives such as the University of Wisconsin solution or one of the specific designed storage solutions like TiProtec™ or Somaluthion™. Whether these preservation solutions are superior or advantageous remains the subject of further studies. © The Author 2016. Published

  16. On the hydrophilicity of polyzwitterion poly (N,N-dimethyl-N-(3-(methacrylamido)propyl)ammoniopropane sulfonate) in water, deuterated water, and aqueous salt solutions.

    PubMed

    Hildebrand, Viet; Laschewsky, André; Zehm, Daniel

    2014-01-01

    A series of zwitterionic model polymers with defined molar masses up to 150,000 Da and defined end groups are prepared from sulfobetaine monomer N,N-dimethyl-N-(3-(methacrylamido)propyl)ammoniopropanesulfonate (SPP). Polymers are synthesized by reversible addition-fragmentation chain transfer polymerization (RAFT) using a functional chain transfer agent labeled with a fluorescent probe. Their upper critical solution temperature-type coil-to-globule phase transition in water, deuterated water, and various salt solutions is studied by turbidimetry. Cloud points increase with polyzwitterion concentration and molar mass, being considerably higher in D2O than in H2O. Moreover, cloud points are strongly affected by the amount and nature of added salts. Typically, they increase with increasing salt concentration up to a maximum value, whereas further addition of salt lowers the cloud points again, mostly down to below freezing point. The different salting-in and salting-out effects of the studied anions can be correlated with the Hofmeister series. In physiological sodium chloride solution and in phosphate buffered saline (PBS), the cloud point is suppressed even for high molar mass samples. Accordingly, SPP-polymers behave strongly hydrophilic under most conditions encountered in biomedical applications. However, the direct transfer of results from model studies in D2O, using, e.g. (1)H NMR or neutron scattering techniques, to 'normal' systems in H2O is not obvious.

  17. Cerebral effects of resuscitation with hypertonic saline and a new low-sodium hypertonic fluid in hemorrhagic shock and head injury.

    PubMed

    Sheikh, A A; Matsuoka, T; Wisner, D H

    1996-07-01

    A 2400-mOsm/L hypertonic solution (isosal) with a lower sodium content, compared with conventional 7.5% hypertonic saline, was formulated using a mixture of sodium chloride, glucose, and mixed amino acids. This solution was developed to minimize hypernatremia during resuscitation. We assessed the effects of isosal on hemodynamics, brain edema, and plasma sodium concentration after head injury associated with hemorrhagic shock. DESIGN. Prospective, randomized laboratory study. University research laboratory. Twenty-one adult female Suffolk sheep, weighing 39 to 49 kg. Animals were subjected to a 2-hr period of hemorrhagic shock to a mean arterial pressure (MAP) of 40 to 45 mm Hg in the presence of a freeze injury to the cerebral cortex. The hemorrhagic shock/head injury phase was followed by 2 hrs of resuscitation with isosal, a new 2400-mosm/L low-sodium hypertonic fluid, 2400 mosm/L of 7.5% hypertonic saline, or lactated Ringer's solution. Initial resuscitation was with a bolus injection of 8 mL/kg of the study solution; subsequent resuscitation in all three groups was with lactated Ringer's solution as needed to maintain baseline cardiac output. Serial hemodynamics, intracranial pressure, electrolytes, and osmolarity were measured. AT the end of resuscitation, the animals were killed and brain water content (mL H2O/g dry weight) of the injured and uninjured areas was determined. Resuscitation volumes were significantly lower in the isosal (19 +/- 5 mL/kg) and 7.5% hypertonic saline (14 +/- 2 mL/mg) groups compared with the lactated Ringer's solution (35 +/- 5 mL/kg) group. Intracranial pressure after 2 hrs of resuscitation was significantly lower in the isosal (7 +/- 1 mm Hg) and hypertonic saline groups (4 +/- 1 mm Hg). Water content in all areas of the brain was significantly lower in the hypertonic saline group compared with the lactated Ringer's solution group. Brain water content in the isosal group was lower than in the lactated Ringer's solution group only

  18. Evolution of the electrical resistivity anisotropy during saline tracer tests: insights from geoelectrical milli-fluidic experiments

    NASA Astrophysics Data System (ADS)

    Jougnot, D.; Jimenez-Martinez, J.; Legendre, R.; Le Borgne, T.; Meheust, Y.; Linde, N.

    2017-12-01

    The use of time-lapse electrical resistivity tomography has been largely developed in environmental studies to remotely monitor water saturation and contaminant plumes migration. However, subsurface heterogeneities, and corresponding preferential transport paths, yield a potentially large anisotropy in the electrical properties of the subsurface. In order to study this effect, we have used a newly developed geoelectrical milli-fluidic experimental set-up with a flow cell that contains a 2D porous medium consisting of a single layer of cylindrical solid grains. We performed saline tracer tests under full and partial water saturations in that cell by jointly injecting air and aqueous solutions with different salinities. The flow cell is equipped with four electrodes to measure the bulk electrical resistivity at the cell's scale. The spatial distribution of the water/air phases and the saline solute concentration field in the water phase are captured simultaneously with a high-resolution camera by combining a fluorescent tracer with the saline solute. These data are used to compute the longitudinal and transverse effective electrical resistivity numerically from the measured spatial distributions of the fluid phases and the salinity field. This approach is validated as the computed longitudinal effective resistivities are in good agreement with the laboratory measurements. The anisotropy in electrical resistivity is then inferred from the computed longitudinal and transverse effective resistivities. We find that the spatial distribution of saline tracer, and potentially air phase, drive temporal changes in the effective resistivity through preferential paths or barriers for electrical current at the pore scale. The resulting heterogeneities in the solute concentrations lead to strong anisotropy of the effective bulk electrical resistivity, especially for partially saturated conditions. Therefore, considering the electrical resistivity as a tensor could improve our

  19. Effect of alternative peritoneal dialysis solutions on cell viability, apoptosis/necrosis and cytokine expression in human monocytes.

    PubMed

    Plum, J; Lordnejad, M R; Grabensee, B

    1998-07-01

    Cellular function, cell viability and the cytokine network of human monocytes are influenced by the specific composition of peritoneal dialysis (PD) fluids. In an in vitro study using isolated human blood monocytes, we investigated the effect of peritoneal dialysates containing amino acids (Amino) or glucose polymer (Glu-poly) instead of glucose (Glu) as the osmotic agent, and bicarbonate (Bic) or PBS instead of lactate (Lac) as a buffer. The following parameters were studied: mitochondrial dehydrogenase activity (using the MTT assay), interleukin (IL)-6 and IL-8 release (ELISA) and cellular IL-6 mRNA expression after lipopolysaccharide (LPS) stimulation (using RT-PCR). FACS flow cytometry with annexin V and propidium iodide as markers and fluorescence microscopic methods were used to study the effects of the test fluids on cell necrosis and apoptosis. Glu/Lac pH 5.5 and Glu-poly/PBS pH 7.4 both significantly reduced mitochondrial dehydrogenase activity by more than 50% after 60 minutes of incubation (30.5 +/- 7.6%, 42.5 +/- 6.5%, referred to RPMI 1640 as 100%). Amino/Bic and Glu/Bic were both superior (Mtt assay > 63%). The rate of necrotic cells after 15 minutes of incubation measured by FACS was mostly increased with Glu/Lac pH 5.5 (29.9 +/- 4.0%). The rate of apoptotic cells, however, was not significantly different between the test solutions. The concentration of IL-6 in the supernatant of stimulated monocytes was highest with Glu/Bic (1023 +/- 278 pg/ml) and Amino/Bic (776 +/- 296 pg/ml) an lowest with Glu/lac pH 5.5 (46 +/- 22 pg/ml) and Glu-poly/PBS (32 +/- 13 pg/ml). IL-8 release from stimulated monocytes showed a similar pattern. Glu-poly/PBS showed a suppressive effect on IL-6 mRNA expression (ratio IL-6/beta-Actin, 0.4 +/- 0.25 vs. RPMI 1.5 +/- 3.6). Bicarbonate buffered solutions both with glucose or amino acids as osmotic agents were superior when regarding cell metabolism, viability and cytokine release, while lactate buffered solutions and Glu-poly/PBS

  20. Tunable and switchable all-fiber comb filter using a PBS-based two-stage cascaded Mach-Zehnder interferometer

    NASA Astrophysics Data System (ADS)

    Luo, Zhi-Chao; Luo, Ai-Ping; Xu, Wen-Cheng

    2011-08-01

    We propose and demonstrate a novel tunable and switchable all-fiber comb filter by employing a polarization beam splitter (PBS)-based two-stage cascaded Mach-Zehnder (M-Z) interferometer. The proposed comb filter consists of a rotatable polarizer, a fiber PBS, a non-3-dB coupler and a 3-dB coupler. By simply adjusting the polarization state of the input light, the dual-function of channel spacing tunable and wavelength switchable (interleaving) operations can be efficiently obtained. The theoretical analysis is verified by the experimental results. A comb filter with both the channel spacing tunable from 0.18 nm to 0.36 nm and the wavelength switchable functions is experimentally demonstrated.

  1. Single-Beam Acoustic Trapping of Red Blood Cells and Polystyrene Microspheres in Flowing Red Blood Cell Saline and Plasma Suspensions.

    PubMed

    Liu, Hsiao-Chuan; Li, Ying; Chen, Ruimin; Jung, Hayong; Shung, K Kirk

    2017-04-01

    Single-beam acoustic tweezers (SBATs) represent a new technology for particle and cell trapping. The advantages of SBATs are their deep penetration into tissues, reduction of tissue damage and ease of application to in vivo studies. The use of these tools for applications in drug delivery in vivo must meet the following conditions: large penetration depth, strong trapping force and tissue safety. A reasonable penetration depth for SBATs in the development of in vivo applications was established in a previous study conducted in water with zero velocity. However, capturing objects in flowing fluid can provide more meaningful results. In this study, we investigated the capability of SBATs to trap red blood cells (RBCs) and polystyrene microspheres in flowing RBC suspensions. Two different types of RBC suspension were prepared in this work: an RBC phosphate-buffered saline (PBS) suspension and an RBC plasma suspension. The results indicated that SBATs successfully trapped RBCs and polystyrene microspheres in a flowing RBC PBS suspension with an average steady velocity of 1.6 cm/s in a 2-mm-diameter polyimide. Furthermore, SBATs were found able to trap RBCs in a flowing RBC PBS suspension at speeds as high as 7.9 cm/s in a polyimide tube, which is higher than the velocity in capillaries (0.03 cm/s) and approaches the velocity in arterioles and venules. Moreover, the results also indicated that polystyrene microspheres can be trapped in an RBC plasma suspension, where aggregation is observed. This work represents a step forward in using this tool in actual in vivo experimentation. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  2. Recombination Suppression in PbS Quantum Dot Heterojunction Solar Cells by Energy-Level Alignment in the Quantum Dot Active Layers.

    PubMed

    Ding, Chao; Zhang, Yaohong; Liu, Feng; Nakazawa, Naoki; Huang, Qingxun; Hayase, Shuzi; Ogomi, Yuhei; Toyoda, Taro; Wang, Ruixiang; Shen, Qing

    2017-09-22

    Using spatial energy-level gradient engineering with quantum dots (QDs) of different sizes to increase the generated carrier collection at the junction of a QD heterojunction solar cell (QDHSC) is a hopeful route for improving the energy-conversion efficiency. However, the results of current related research have shown that a variable band-gap structure in a QDHSC will create an appreciable increase, not in the illumination current density, but rather in the fill factor. In addition, there are a lack of studies on the mechanism of the effect of these graded structures on the photovoltaic performance of QDHSCs. This study presents the development of air atmosphere solution-processed TiO 2 /PbS QDs/Au QDHSCs by engineering the energy-level alignment (ELA) of the active layer via the use of a sorted order of differently sized QD layers (four QD sizes). In comparison to the ungraded device (without the ELA), the optimized graded architecture (containing the ELA) solar cells exhibited a great increase (21.4%) in short-circuit current density (J sc ). As a result, a J sc value greater than 30 mA/cm 2 has been realized in planar, thinner absorption layer (∼300 nm) PbS QDHSCs, and the open-circuit voltage (V oc ) and power-conversion efficiency (PCE) were also improved. Through characterization by the light intensity dependences of the J sc and V oc and transient photovoltage decay, we find that (i) the ELA structure, serving as an electron-blocking layer, reduces the interfacial recombination at the PbS/anode interface, and (ii) the ELA structure can drive more carriers toward the desirable collection electrode, and the additional carriers can fill the trap states, reducing the trap-assisted recombination in the PbS QDHSCs. This work has clearly elucidated the mechanism of the recombination suppression in the graded QDHSCs and demonstrated the effects of ELA structure on the improvement of J sc . The charge recombination mechanisms characterized in this work would be

  3. Immersing lungs in hydrogen-rich saline attenuates lung ischaemia-reperfusion injury.

    PubMed

    Takahashi, Mamoru; Chen-Yoshikawa, Toyofumi F; Saito, Masao; Tanaka, Satona; Miyamoto, Ei; Ohata, Keiji; Kondo, Takeshi; Motoyama, Hideki; Hijiya, Kyoko; Aoyama, Akihiro; Date, Hiroshi

    2017-03-01

    Anti-oxidant effects of hydrogen have been reported in studies examining ischaemia-reperfusion injury (IRI). In this study, we evaluated the therapeutic efficacy of immersing lungs in hydrogen-rich saline on lung IRI. Lewis rats were divided into three groups: (i) sham, (ii) normal saline and (iii) hydrogen-rich saline. In the first experiment, the left thoracic cavity was filled with either normal saline or hydrogen-rich saline for 1 h. Then, we measured the hydrogen concentration in the left lung using a sensor gas chromatograph ( N = 3 per group). In the second experiment, lung IRI was induced by occlusion of the left pulmonary hilum for 1 h, followed by reperfusion for 3 h. During the ischaemic period, the left thoracic cavity was filled with either normal saline or hydrogen-rich saline. After reperfusion, we assessed lung function, histological changes and cytokine production ( N = 5-7 per group). Immersing lungs in hydrogen-rich saline resulted in an elevated hydrogen concentration in the lung (6.9 ± 2.9 μmol/1 g lung). After IRI, pulmonary function (pulmonary compliance and oxygenation levels) was significantly higher in the hydrogen-rich saline group than in the normal saline group ( P  < 0.05). Similarly, pro-inflammatory cytokine levels (interleukin-1β and interleukin-6) in the left lung were significantly lower in the hydrogen-rich saline group than in the normal saline group ( P  < 0.05). Immersing lungs in hydrogen-rich saline delivered hydrogen into the lung and consequently attenuated lung IRI. Hydrogen-rich solution appears to be a promising approach to managing lung IRI. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  4. Vein Graft Preservation Solutions, Patency, and Outcomes After Coronary Artery Bypass Graft Surgery

    PubMed Central

    Harskamp, Ralf E.; Alexander, John H.; Schulte, Phillip J.; Brophy, Colleen M.; Mack, Michael J.; Peterson, Eric D.; Williams, Judson B.; Gibson, C. Michael; Califf, Robert M.; Kouchoukos, Nicholas T.; Harrington, Robert A.; Ferguson, T. Bruce; Lopes, Renato D.

    2015-01-01

    IMPORTANCE In vitro and animal model data suggest that intraoperative preservation solutions may influence endothelial function and vein graft failure (VGF) after coronary artery bypass graft (CABG) surgery. Clinical studies to validate these findings are lacking. OBJECTIVE To evaluate the effect of vein graft preservation solutions on VGF and clinical outcomes in patients undergoing CABG surgery. DESIGN, SETTING, AND PARTICIPANTS Data from the Project of Ex-Vivo Vein Graft Engineering via Transfection IV (PREVENT IV) study, a phase 3, multicenter, randomized, double-blind, placebo-controlled trial that enrolled 3014 patients at 107 US sites from August 1, 2002, through October 22, 2003, were used. Eligibility criteria for the trial included CABG surgery for coronary artery disease with at least 2 planned vein grafts. INTERVENTIONS Preservation of vein grafts in saline, blood, or buffered saline solutions. MAIN OUTCOMES AND MEASURES One-year angiographic VGF and 5-year rates of death, myocardial infarction, and subsequent revascularization. RESULTS Most patients had grafts preserved in saline (1339 [44.4%]), followed by blood (971 [32.2%]) and buffered saline (507 [16.8%]). Baseline characteristics were similar among groups. One-year VGF rates were much lower in the buffered saline group than in the saline group (patient-level odds ratio [OR], 0.59 [95% CI, 0.45-0.78; P < .001]; graft-level OR, 0.63 [95% CI, 0.49-0.79; P < .001]) or the blood group (patient-level OR, 0.62 [95% CI, 0.46-0.83; P = .001]; graft-level OR, 0.63 [95% CI, 0.48-0.81; P < .001]). Use of buffered saline solution also tended to be associated with a lower 5-year risk for death, myocardial infarction, or subsequent revascularization compared with saline (hazard ratio, 0.81 [95% CI, 0.64-1.02; P = .08]) and blood (0.81 [0.63-1.03; P = .09]) solutions. CONCLUSIONS AND RELEVANCE Patients undergoing CABG whose vein grafts were preserved in a buffered saline solution had lower VGF rates and trends

  5. Signal Amplification in Field Effect-Based Sandwich Enzyme-Linked Immunosensing by Tuned Buffer Concentration with Ionic Strength Adjuster.

    PubMed

    Kumar, Satyendra; Kumar, Narendra; Panda, Siddhartha

    2016-04-01

    Miniaturization of the sandwich enzyme-based immunosensor has several advantages but could result in lower signal strength due to lower enzyme loading. Hence, technologies for amplification of the signal are needed. Signal amplification in a field effect-based electrochemical immunosensor utilizing chip-based ELISA is presented in this work. First, the molarities of phosphate buffer saline (PBS) and concentrations of KCl as ionic strength adjuster were optimized to maximize the GOx glucose-based enzymatic reactions in a beaker for signal amplification measured by change in the voltage shift with an EIS device (using 20 μl of solution) and validated with a commercial pH meter (using 3 ml of solution). The PBS molarity of 100 μM with 25 mM KCl provided the maximum voltage shift. These optimized buffer conditions were further verified for GOx immobilized on silicon chips, and similar trends with decreased PBS molarity were obtained; however, the voltage shift values obtained on chip reaction were lower as compared to the reactions occurring in the beaker. The decreased voltage shift with immobilized enzyme on chip could be attributed to the increased Km (Michaelis-Menten constant) values in the immobilized GOx. Finally, a more than sixfold signal enhancement (from 8 to 47 mV) for the chip-based sandwich immunoassay was obtained by altering the PBS molarity from 10 to 100 μM with 25 mM KCl.

  6. Effect of povidone-iodine addition on the corrosion behavior of cp-Ti in normal saline.

    PubMed

    Bhola, Rahul; Bhola, Shaily M; Mishra, Brajendra; Olson, David L

    2010-05-01

    The effect of various concentrations of povidone-iodine (PI) on the corrosion behavior of a commercially pure titanium alloy (Ti-1) has been investigated in normal saline solution to simulate the povidone-iodine addition in an oral environment. The open circuit potential, electrochemical impedance spectroscopy and potentiodynamic polarization measurements have been used to characterize the electrochemical phenomena occurring on the alloy surface. The open circuit potential values for Ti-1 in various concentrations of PI shift considerably towards noble direction as compared to pure normal saline. In the potentiodynamic polarization curve for Ti-1 in various solutions, the cathodic current density has increased for all concentrations of PI and the anodic current density has decreased. Only the 0.1% PI concentration is able to inhibit corrosion of Ti-1 in normal saline and the other higher concentrations studied, accelerate corrosion. The EIS data for Ti-1 in normal saline and in various concentrations of PI follows a one time constant circuit, suggesting the formation of a single passive film on Ti-1 which is not altered by the addition of PI to normal saline.

  7. Effect of Gd3+ Ions on the Thermal Behavior, Optical, Electrical and Magnetic Properties of PbS Thin Films

    NASA Astrophysics Data System (ADS)

    Ravishankar, S.; Balu, A. R.; Nagarethinam, V. S.

    2018-02-01

    This paper reports the effect of Gd doping concentration on the thermal behavior, structural, morphological, optical, electrical and magnetic properties of PbS thin films. Gd doping concentration in PbS was varied as 0 wt.%, 1 wt.%, 2 wt.%, 3 wt.% and 4 wt.%, respectively. Thermogravimetric-Differential Thermal Analysis curves confirm that both the undoped and doped films become well crystallized above 354°C and 342°C, respectively. X-ray diffraction studies confirm that all the films exhibit face-centered cubic crystal structure with a strong (2 0 0) preferential growth. Undoped films exhibit triangular-shaped grains which modify to small cuboids with Gd doping. Energy dispersive x-ray spectra confirm the presence of Gd in the doped films. Transmission electron microscopy images confirm the presence of nanosized grains for both the undoped and doped films. The doped films showed increased transparency and improved magnetic behaviour. The results obtained confirm that Gd3+, a rare earth ion, strongly influences the physical properties of PbS thin films to a large extent.

  8. Plasmonically enhanced electromotive force of narrow bandgap PbS QD-based photovoltaics.

    PubMed

    Li, Xiaowei; McNaughter, Paul D; O'Brien, Paul; Minamimoto, Hiro; Murakoshi, Kei

    2018-05-30

    Electromotive force of photovoltaics is a key to define the output power density of photovoltaics. Multiple exciton generation (MEG) exhibited by semiconductor quantum dots (QDs) has great potential to enhance photovoltaic performance owing to the ability to generate more than one electron-hole pairs when absorbing a single photon. However, even in MEG-based photovoltaics, limitation of modifying the electromotive force exists due to the intrinsic electrochemical potential of the conduction band-edges of QDs. Here we report a pronouncedly improved photovoltaic performance by constructing a PbS QD-sensitized electrode that comprises plasmon-active Au nanoparticles embedded in a titanium dioxide thin film. Significant enhancement on electromotive force is characterized by the onset potential of photocurrent generation using MEG-effective PbS QDs with a narrow bandgap energy (Eg = 0.9 eV). By coupling with localized surface plasmon resonance (LSPR), such QDs exhibit improved photoresponses and the highest output power density over the other QDs with larger bandgap energies (Eg = 1.1 and 1.7 eV) under visible light irradiation. The wavelength-dependent onset potential and the output power density suggest effective electron injection owing to the enhanced density of electrons excited by energy overlapping between MEG and LSPR.

  9. Salinity controls on plant transpiration and soil water balance

    NASA Astrophysics Data System (ADS)

    Perri, S.; Molini, A.; Suweis, S. S.; Viola, F.; Entekhabi, D.

    2017-12-01

    Soil salinization and aridification represent a major threat for the food security and sustainable development of drylands. The two problems are deeply connected, and their interplay is expected to be further enhanced by climate change and projected population growth. Salt-affected land is currently estimated to cover around 1.1 Gha, and is particularly widespread in semi-arid to hyper-arid climates. Over 900 Mha of these saline/sodic soils are potentially available for crop or biomass production. Salt-tolerant plants have been recently proposed as valid solution to exploit or even remediate salinized soils. However the effects of salinity on evapotranspiration, soil water balance and the long-term salt mass balance in the soil, are still largely unexplored. In this contribution we analyze the feedback of evapotranspiration on soil salinization, with particular emphasis on the role of vegetation and plant salt-tolerance. The goal is to introduce a simple modeling framework able to shed some light on how (a) soil salinity controls plant transpiration, and (b) salinization itself is favored/impeded by different vegetation feedback. We introduce at this goal a spatially lumped stochastic model of soil moisture and salt mass dynamics averaged over the active soil depth, and accounting for the effect of salinity on evapotranspiration. Here, the limiting effect of salinity on ET is modeled through a simple plant response function depending on both salt concentration in the soil and plant salt-tolerance. The coupled soil moisture and salt mass balance is hence used to obtain the conditional steady-state probability density function (pdf) of soil moisture for given salt tolerance and salinization level, Our results show that salinity imposes a limit in the soil water balance and this limit depends on plant salt-tolerance mainly through the control of the leaching occurrence (tolerant plants exploit water more efficiently than the sensitive ones). We also analyzed the

  10. Oscillating Adriatic temperature and salinity regimes mapped using the Self-Organizing Maps method

    NASA Astrophysics Data System (ADS)

    Matić, Frano; Kovač, Žarko; Vilibić, Ivica; Mihanović, Hrvoje; Morović, Mira; Grbec, Branka; Leder, Nenad; Džoić, Tomislav

    2017-01-01

    This paper aims to document salinity and temperature regimes in the middle and south Adriatic Sea by applying the Self-Organizing Maps (SOM) method to the available long-term temperature and salinity series. The data were collected on a seasonal basis between 1963 and 2011 in two dense water collecting depressions, Jabuka Pit and Southern Adriatic Pit, and over the Palagruža Sill. Seasonality was removed prior to the analyses. Salinity regimes have been found to oscillate rapidly between low-salinity and high-salinity SOM solutions, ascribed to the advection of Western and Eastern Mediterranean waters, respectively. Transient salinity regimes normally lasted less than a season, while temperature transient regimes lasted longer. Salinity regimes prolonged their duration after the major basin-wide event, the Eastern Mediterranean Transient, in the early 1990s. A qualitative relationship between high-salinity regimes and dense water formation and dynamics has been documented. The SOM-based analyses have a large capacity for classifying the oscillating ocean regimes in a basin, which, in the case of the Adriatic Sea, beside climate forcing, is an important driver of biogeochemical changes that impacts trophic relations, appearance and abundance of alien organisms, and fisheries, etc.

  11. Effect of sodium hypochlorite and saline on cyclic fatigue resistance of WaveOne Gold and Reciproc reciprocating instruments.

    PubMed

    Elnaghy, A M; Elsaka, S E

    2017-10-01

    To compare the cyclic fatigue resistance of WaveOne Gold (Dentsply Tulsa Dental Specialties, Tulsa, OK, USA) and Reciproc (VDW, Munich, Germany) reciprocating instruments during immersion in sodium hypochlorite (NaOCl) and saline solutions at body temperature. A total of 180 new WaveOne Gold primary size 25, .07 taper, and Reciproc size 25, .08 taper were randomly divided into three groups: group 1: no immersion (control, air); group 2: immersion in saline at 37 ± 1 °C; and group 3: immersion in 5% NaOCl at 37 ± 1 °C. The instruments were reciprocated in the test solution until fracture, and the number of cycles to failure was recorded. The data were analysed statistically using t-tests and one-way analysis of variance (anova) with the significance level set at P < 0.05. A Weibull analysis was performed on number of cycles to failure data. WaveOne Gold instruments had significantly greater number of cycles to failure than Reciproc instruments in all groups (P < 0.001). Fatigue resistance for both instruments tested in air was significantly higher than that in saline and NaOCl solutions (P < 0.001). For both instruments, there was no significant difference in the fatigue resistance between saline and NaOCl solutions (P > 0.05). The Weibull analysis showed that the predicted cycles of WaveOne Gold in air was 1027 cycles for 99% survival. However, Reciproc instruments tested in NaOCl solution had the lowest predicted cycles (613 cycles) among the groups. Immersion of WaveOne Gold and Reciproc reciprocating instruments in saline and NaOCl solutions decreased considerably their cyclic fatigue resistance. The fatigue resistance of WaveOne Gold instruments was higher than that of Reciproc instruments. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  12. Corneal epithelial cell biocompatibility to silicone hydrogel and conventional hydrogel contact lens packaging solutions.

    PubMed

    Gorbet, M B; Tanti, N C; Jones, L; Sheardown, H

    2010-02-19

    Although all contact lenses (CLs) are applied initially to the eye directly from a packaging solution, little is known about the effects of these solutions on human corneal epithelial cells (HCECs). Due to the porous nature of CL materials, they have the potential to sorb components of the packaging solution during storage, which could then be subsequently released upon insertion of the CL on the eye. The purpose of this study was to investigate the effect of various packaging solutions on HCECs, using an in vitro model. An in vitro assay was developed whereby various silicone hydrogels and conventional, poly-2-hydroxyethylmethacrylate (polyHEMA)-based lens materials were removed directly from their packaging and then incubated for up to 24 h with HCECs. The effect of the retained and released packaging solution components on HCECs was assessed by measuring cell viability, adhesion phenotype, and apoptosis. Incubation of HCECs with CLs stored in borate-buffered packaging solutions resulted in a significant reduction in cell viability. Adherent cells incubated with these CLs also exhibited reduced levels of beta(1) and alpha(3) integrin. Soaking borate-buffered packaged CLs in PBS before cell incubation resolved viability and integrin expression in all cases, with the exception of galyfilcon A and balafilcon A, from which a 20% reduction in cell viability was still observed. In comparison, CLs stored in phosphate-buffered packaging solutions had cellular viability and expression of integrins similar to control cells (cells incubated in the absence of a lens). When incubated with cells at a 10% concentration in serum-free medium, borate-buffered packaging solutions and borate-containing saline (Unisol 4) significantly reduced cell viability and integrin expression. Neither caspase activation nor annexin V binding was observed on cells following exposure to borate buffer solution. However, a significant decrease in reactive oxygen species was observed at 24 h. These

  13. Direct work function measurement by gas phase photoelectron spectroscopy and its application on PbS nanoparticles.

    PubMed

    Axnanda, Stephanus; Scheele, Marcus; Crumlin, Ethan; Mao, Baohua; Chang, Rui; Rani, Sana; Faiz, Mohamed; Wang, Suidong; Alivisatos, A Paul; Liu, Zhi

    2013-01-01

    Work function is a fundamental property of a material's surface. It is playing an ever more important role in engineering new energy materials and efficient energy devices, especially in the field of photovoltaic devices, catalysis, semiconductor heterojunctions, nanotechnology, and electrochemistry. Using ambient pressure X-ray photoelectron spectroscopy (APXPS), we have measured the binding energies of core level photoelectrons of Ar gas in the vicinity of several reference materials with known work functions (Au(111), Pt(111), graphite) and PbS nanoparticles. We demonstrate an unambiguously negative correlation between the work functions of reference samples and the binding energies of Ar 2p core level photoelectrons detected from the Ar gas near the sample surface region. Using this experimentally determined linear relationship between the surface work function and Ar gas core level photoelectron binding energy, we can measure the surface work function of different materials under different gas environments. To demonstrate the potential applications of this ambient pressure XPS technique in nanotechnology and solar energy research, we investigate the work functions of PbS nanoparticles with various capping ligands: methoxide, mercaptopropionic acid, and ethanedithiol. Significant Fermi level position changes are observed for PbS nanoparticles when the nanoparticle size and capping ligands are varied. The corresponding changes in the valence band maximum illustrate that an efficient quantum dot solar cell design has to take into account the electrochemical effect of the capping ligand as well.

  14. Physiological and Biochemical Responses of Lavandula angustifolia to Salinity Under Mineral Foliar Application

    PubMed Central

    Chrysargyris, Antonios; Michailidi, Evgenia; Tzortzakis, Nikos

    2018-01-01

    Saline water has been proposed as a solution to partially cover plant water demands due to scarcity of irrigation water in hot arid areas. Lavender (Lavandula angustifolia Mill.) plants were grown hydroponically under salinity (0–25–50–100 mM NaCl). The overcome of salinity stress was examined by K, Zn, and Si foliar application for the plant physiological and biochemical characteristics. The present study indicated that high (100 mM NaCl) salinity decreased plant growth, content of phenolics and antioxidant status and essential oil (EO) yield, while low-moderate salinity levels maintained the volatile oil profile in lavender. The integrated foliar application of K and Zn lighten the presumable detrimental effects of salinity in terms of fresh biomass, antioxidant capacity, and EO yield. Moderate salinity stress along with balanced concentration of K though foliar application changed the primary metabolites pathways in favor of major volatile oil constituents biosynthesis and therefore lavender plant has the potential for cultivation under prevalent semi-saline conditions. Zn and Si application, had lesser effects on the content of EO constituents, even though altered salinity induced changings. Our results have demonstrated that lavender growth/development and EO production may be affected by saline levels, whereas mechanisms for alteration of induced stress are of great significance considering the importance of the oil composition, as well. PMID:29731759

  15. Physiological and Biochemical Responses of Lavandula angustifolia to Salinity Under Mineral Foliar Application.

    PubMed

    Chrysargyris, Antonios; Michailidi, Evgenia; Tzortzakis, Nikos

    2018-01-01

    Saline water has been proposed as a solution to partially cover plant water demands due to scarcity of irrigation water in hot arid areas. Lavender ( Lavandula angustifolia Mill.) plants were grown hydroponically under salinity (0-25-50-100 mM NaCl). The overcome of salinity stress was examined by K, Zn, and Si foliar application for the plant physiological and biochemical characteristics. The present study indicated that high (100 mM NaCl) salinity decreased plant growth, content of phenolics and antioxidant status and essential oil (EO) yield, while low-moderate salinity levels maintained the volatile oil profile in lavender. The integrated foliar application of K and Zn lighten the presumable detrimental effects of salinity in terms of fresh biomass, antioxidant capacity, and EO yield. Moderate salinity stress along with balanced concentration of K though foliar application changed the primary metabolites pathways in favor of major volatile oil constituents biosynthesis and therefore lavender plant has the potential for cultivation under prevalent semi-saline conditions. Zn and Si application, had lesser effects on the content of EO constituents, even though altered salinity induced changings. Our results have demonstrated that lavender growth/development and EO production may be affected by saline levels, whereas mechanisms for alteration of induced stress are of great significance considering the importance of the oil composition, as well.

  16. Postprocedural pain in shoulder arthrography: differences between using preservative-free normal saline and normal saline with benzyl alcohol as an intraarticular contrast diluent.

    PubMed

    Storey, Troy F; Gilbride, George; Clifford, Kelly

    2014-11-01

    The purpose of this study was to prospectively evaluate the effect of benzyl alcohol, a common preservative in normal saline, on postprocedural pain after intraarticular injection for direct shoulder MR arthrography. From April 2011 through January 2013, 138 patients underwent direct shoulder MR arthrography. Using the Wong-Baker Faces Pain Scale, patients were asked to report their shoulder pain level immediately before and immediately after the procedure and then were contacted by telephone 6, 24, and 48 hours after the procedure. Fourteen patients did not receive the prescribed amount of contrast agent for diagnostic reasons or did not complete follow-up. Sixty-two patients received an intraarticular solution including preservative-free normal saline (control group) and 62 patients received an intraarticular solution including normal saline with 0.9% benzyl alcohol as a contrast diluent (test group). Patients were randomized as to which intraarticular diluent they received. Fluoroscopic and MR images were reviewed for extracapsular contrast agent administration or extravasation, full-thickness rotator cuff tears, and adhesive capsulitis. The effect of preservative versus control on pain level was estimated with multiple regression, which included time after procedure as the covariate and accounted for repeated measures over patients. Pain scale scores were significantly (p = 0.0382) higher (0.79 units; 95% CI, 0.034-1.154) with benzyl alcohol preservative compared with control (saline). In both study arms, the pain scale scores decreased slightly after the procedure, increased by roughly 1 unit over baseline for the test group and 0.3 unit over baseline for the control group by 6 hours after the procedure, were 0.50 unit over baseline for the test group and 0.12 unit over baseline for the control group at 24 hours, then fell to be slightly greater than baseline at 48 hours with benzyl alcohol and slightly less than baseline without benzyl alcohol. These trends

  17. Analytical steady-state solutions for water-limited cropping systems using saline irrigation water

    USDA-ARS?s Scientific Manuscript database

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mod...

  18. Plant aquaporins: new perspectives on water and nutrient uptake in saline environment.

    PubMed

    del Martínez-Ballesta, M C; Silva, C; López-Berenguer, C; Cabañero, F J; Carvajal, M

    2006-09-01

    The mechanisms of salt stress and tolerance have been targets for genetic engineering, focusing on ion transport and compartmentation, synthesis of compatible solutes (osmolytes and osmoprotectants) and oxidative protection. In this review, we consider the integrated response to salinity with respect to water uptake, involving aquaporin functionality. Therefore, we have concentrated on how salinity can be alleviated, in part, if a perfect knowledge of water uptake and transport for each particular crop and set of conditions is available.

  19. The in situ synthesis of PbS nanocrystals from lead(II) n-octylxanthate within a 1,3-diisopropenylbenzene–bisphenol A dimethacrylate sulfur copolymer

    PubMed Central

    Bear, J. C.; Mayes, A. G.; Parkin, I. P.; O'Brien, P.

    2017-01-01

    The synthesis of lead sulfide nanocrystals within a solution processable sulfur ‘inverse vulcanization’ polymer thin film matrix was achieved from the in situ thermal decomposition of lead(II) n-octylxanthate, [Pb(S2COOct)2]. The growth of nanocrystals within polymer thin films from single-source precursors offers a faster route to networks of nanocrystals within polymers when compared with ex situ routes. The ‘inverse vulcanization’ sulfur polymer described herein contains a hybrid linker system which demonstrates high solubility in organic solvents, allowing solution processing of the sulfur-based polymer, ideal for the formation of thin films. The process of nanocrystal synthesis within sulfur films was optimized by observing nanocrystal formation by X-ray photoelectron spectroscopy and X-ray diffraction. Examination of the film morphology by scanning electron microscopy showed that beyond a certain precursor concentration the nanocrystals formed were not only within the film but also on the surface suggesting a loading limit within the polymer. We envisage this material could be used as the basis of a new generation of materials where solution processed sulfur polymers act as an alternative to traditional polymers. PMID:28878986

  20. Salt exclusion and mycorrhizal symbiosis increase tolerance to NaCl and CaCl2 salinity in ‘Siam Queen’ basil

    USDA-ARS?s Scientific Manuscript database

    A study was conducted to evaluate the effects of salinity on growth and nutrient uptake in basil (Ocimum basilicum L.). Plants were fertilized with a complete nutrient solution and exposed to no, low, or moderate levels of salinity from NaCl or CaCl2. Plants in the control and moderate salinity tre...

  1. Structures of two intermediate phases between the B1 and B2 phases of PbS under high pressure

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Yanchun, E-mail: liyc@ihep.ac.cn, E-mail: liuj@ihep.ac.cn; Lin, Chuanlong; Li, Xiaodong

    2014-12-15

    The structural transitions of PbS were investigated at pressures up to 50 GPa using synchrotron powder and single crystal X-ray diffraction (XRD) methods in diamond anvil cells. We found two intermediate phases between the B1 phase under atmospheric pressure and the B2 phase at 21.1 GPa, which is different to previous reports. The structures of these two intermediate phases were indexed as B27 and B33, respectively. Their structural parameters were investigated using density functional theory (DFT) calculations. Our results provide a new insight into understanding the transition pathway between the B1 and B2 phases in PbS.

  2. Stochastic modeling of soil salinity

    NASA Astrophysics Data System (ADS)

    Suweis, S.; Porporato, A. M.; Daly, E.; van der Zee, S.; Maritan, A.; Rinaldo, A.

    2010-12-01

    A minimalist stochastic model of primary soil salinity is proposed, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The equations for the probability density functions of salt mass and concentration are found by reducing the coupled soil moisture and salt mass balance equations to a single stochastic differential equation (generalized Langevin equation) driven by multiplicative Poisson noise. Generalized Langevin equations with multiplicative white Poisson noise pose the usual Ito (I) or Stratonovich (S) prescription dilemma. Different interpretations lead to different results and then choosing between the I and S prescriptions is crucial to describe correctly the dynamics of the model systems. We show how this choice can be determined by physical information about the timescales involved in the process. We also show that when the multiplicative noise is at most linear in the random variable one prescription can be made equivalent to the other by a suitable transformation in the jump probability distribution. We then apply these results to the generalized Langevin equation that drives the salt mass dynamics. The stationary analytical solutions for the probability density functions of salt mass and concentration provide insight on the interplay of the main soil, plant and climate parameters responsible for long term soil salinization. In particular, they show the existence of two distinct regimes, one where the mean salt mass remains nearly constant (or decreases) with increasing rainfall frequency, and another where mean salt content increases markedly with increasing rainfall frequency. As a result, relatively small reductions of rainfall in drier climates may entail dramatic shifts in longterm soil salinization trends, with significant consequences, e.g. for climate change impacts on rain fed agriculture.

  3. Interferon Gamma as a Biomarker of Exposure to Enteric Viruses

    EPA Science Inventory

    Interferon gamma (IFN-γ) was selected as a biomarker for viral exposure. Twelve-week-old BALB/c mice were intraperitoneally injected with Coxsackievirus B3 or B4 diluted in phosphate-buffered saline (PBS). Control mice were injected with PBS only. Four months after viral infectio...

  4. Microbial fuel cells in saline and hypersaline environments: Advancements, challenges and future perspectives.

    PubMed

    Grattieri, Matteo; Minteer, Shelley D

    2018-04-01

    This review is aimed to report the possibility to utilize microbial fuel cells for the treatment of saline and hypersaline solutions. An introduction to the issues related with the biological treatment of saline and hypersaline wastewater is reported, discussing the limitation that characterizes classical aerobic and anaerobic digestions. The microbial fuel cell (MFC) technology, and the possibility to be applied in the presence of high salinity, is discussed before reviewing the most recent advancements in the development of MFCs operating in saline and hypersaline conditions, with their different and interesting applications. Specifically, the research performed in the last 5years will be the main focus of this review. Finally, the future perspectives for this technology, together with the most urgent research needs, are presented. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Effect of temperature, light and salinity on seed germination and radicle growth of the geographically widespread halophyte shrub Halocnemum strobilaceum.

    PubMed

    Qu, Xiao-Xia; Huang, Zhen-Ying; Baskin, Jerry M; Baskin, Carol C

    2008-01-01

    The small leafy succulent shrub Halocnemum strobilaceum occurs in saline habitats from northern Africa and Mediterranean Europe to western Asia, and it is a dominant species in salt deserts such as those of north-west China. The effects of temperature, light/darkness and NaCl salinity were tested on seed germination, and the effects of salinity were tested on seed germination recovery, radicle growth and radicle elongation recovery, using seeds from north-west China; the results were compared with those previously reported on this species from 'salt steppes' in the Mediterranean region of Spain. Seed germination was tested over a range of temperatures in light and in darkness and over a range of salinities at 25 degrees C in the light. Seeds that did not germinate in the NaCl solutions were tested for germination in deionized water. Seeds from which radicles had barely emerged in deionized water were transferred to NaCl solutions for 10 d and then back to deionized water for 10 d to test for radicle growth and recovery. Seeds germinated to higher percentages in light than in darkness and at high than at low temperatures. Germination percentages decreased with an increase in salinity from 0.1 to 0.75 M NaCl. Seeds that did not germinate in NaCl solutions did so after transfer to deionized water. Radicle elongation was increased by low salinity, and then it decreased with an increase in salinity, being completely inhibited by > or = 2.0 M NaCl. Elongation of radicles from salt solutions < 3.0 M resumed after seedlings were transferred to deionized water. The seed and early seedling growth stages of the life cycle of H. strobilaceum are very salt tolerant, and their physiological responses differ somewhat between the Mediterranean 'salt steppe' of Spain and the inland cold salt desert of north-west China.

  6. 76 FR 6792 - Federal Management Regulation; FMR Bulletin PBS-2011-B1; Redesignations of Federal Buildings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-08

    ... Management Regulation; FMR Bulletin PBS-2011-B1; Redesignations of Federal Buildings AGENCY: Public Buildings... announces the redesignations of three Federal buildings. DATES: Expiration Date: This bulletin announcement expires June 30, 2011. The building redesignations remain in effect until canceled or superseded by...

  7. 76 FR 54772 - Federal Management Regulation; FMR Bulletin PBS-2011-B2; Redesignations of Federal Buildings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-02

    ... Management Regulation; FMR Bulletin PBS-2011-B2; Redesignations of Federal Buildings AGENCY: Public Buildings... announces the designation and redesignation of two Federal buildings. Expiration Date: This bulletin announcement expires January 31, 2012. The building designation and redesignation remains in effect until...

  8. 75 FR 69080 - Federal Management Regulation; FMR Bulletin PBS-2010-B5; Redesignations of Federal Buildings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-10

    ... Management Regulation; FMR Bulletin PBS-2010-B5; Redesignations of Federal Buildings AGENCY: Public Buildings... announces the designation and redesignation of two Federal buildings. DATES: Expiration Date: This bulletin announcement expires April 30, 2011. The building designation and redesignation remains in effect until...

  9. SU-F-T-194: Analyzing the Effect of Range Shifter Air Gap On TPS Dose Modeling Accuracy in Superficial PBS Proton Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shirey, R; Wu, H

    2016-06-15

    Purpose: Treatment planning systems (TPS) may not accurately model superficial dose distributions of range shifted proton pencil beam scanning (PBS) treatments. Numerous patient-specific QA tests performed on superficially treated PBS plans have shown a consistent overestimate of dose by the TPS. This study quantifies variations between TPS planned dose and measured dose as a function of range shifter air gap and treatment depths up to 5 cm. Methods: PBS treatment plans were created in the TPS to uniformly irradiate a volume of solid water. One plan was created for each range shifter position analyzed, and all plans utilized identical dosemore » optimization parameters. Each optimized plan was analyzed in the TPS to determine the planned dose at varying depths. A PBS proton therapy system with a 3.5 cm lucite range shifter delivered the treatment plans, and a parallel plate chamber embedded in RW3 solid water measured dose at shallow depths for each air gap. Differences between measured and planned doses were plotted and analyzed. Results: The data show that the TPS more accurately models superficial dose as the air gap between the range shifter and patient surface decreases. Air gaps less than 10 cm have an average dose difference of only 1.6%, whereas air gaps between 10 and 20 cm differ by 3.0% and gaps greater than 20 cm differ by 4.4%. Conclusion: This study has shown that the TPS is unable to accurately model superficial dose with a large range shifter air gap. Dose differences greater than 3% will likely cause QA failure, as many institutions analyze patient QA with a 3%/3mm gamma analysis. For superficial PBS therapy, range shifter positions should be chosen to keep the air gap less then 10 cm when patient setup and gantry geometry allow.« less

  10. Glucose buffer is suitable for blood group conversion with α-N acetylgalactosaminidase and α-galactosidase.

    PubMed

    Gao, Hong-Wei; Li, Su-Bo; Bao, Guo-Qiang; Zhang, Xue; Li, Hui; Wang, Ying-Li; Tan, Ying-Xia; Ji, Shou-Ping; Gong, Feng

    2014-01-01

    It is well known that the buffer plays a key role in the enzymatic reaction involved in blood group conversion. In previous study, we showed that a glycine buffer is suitable for A to O or B to O blood group conversion. In this study, we investigated the use of 5% glucose and other buffers for A to O or B to O blood group conversion by α-N-acetylgalactosaminidase or α-galactosidase. We compared the binding ability of α-N-acetylgalactosaminidase/α-galactosidase with red blood cells (RBC) in different reaction buffers, such as normal saline, phosphate-buffered saline (PBS), a disodium hydrogen phosphate-based buffer (PCS), and 5% commercial glucose solution. The doses of enzymes necessary for the A/B to O conversion in different reaction buffers were determined and compared. The enzymes' ability to bind to RBC was evaluated by western blotting, and routine blood typing and fluorescence activated cell sorting was used to evaluate B/A to O conversion efficiency. The A to O conversion efficiency in glucose buffer was similar to that in glycine buffer with the same dose (>0.06 mg/mL pRBC). B to O conversion efficiency in glucose buffer was also similar to that in glycine buffer with the same dose (>0.005 mg/mL pRBC). Most enzymes could bind with RBC in glycine or glucose buffer, but few enzymes could bind with RBC in PBS, PCS, or normal saline. These results indicate that 5% glucose solution provides a suitable condition for enzymolysis, especially for enzymes combining with RBC. Meanwhile, the conversion efficiency of A/B to O was similar in glucose buffer and glycine buffer. Moreover, 5% glucose solution has been used for years in venous transfusion, it is safe for humans and its cost is lower. Our results do, therefore, suggest that 5% glucose solution could become a novel suitable buffer for A/B to O blood group conversion.

  11. Glucose buffer is suitable for blood group conversion with α-N acetylgalactosaminidase and α-galactosidase

    PubMed Central

    Gao, Hong-Wei; Li, Su-Bo; Bao, Guo-Qiang; Zhang, Xue; Li, Hui; Wang, Ying-Li; Tan, Ying-Xia; Ji, Shou-Ping; Gong, Feng

    2014-01-01

    Background It is well known that the buffer plays a key role in the enzymatic reaction involved in blood group conversion. In previous study, we showed that a glycine buffer is suitable for A to O or B to O blood group conversion. In this study, we investigated the use of 5% glucose and other buffers for A to O or B to O blood group conversion by α-N-acetylgalactosaminidase or α-galactosidase. Materials and methods We compared the binding ability of α-N-acetylgalactosaminidase/α-galactosidase with red blood cells (RBC) in different reaction buffers, such as normal saline, phosphate-buffered saline (PBS), a disodium hydrogen phosphate-based buffer (PCS), and 5% commercial glucose solution. The doses of enzymes necessary for the A/B to O conversion in different reaction buffers were determined and compared. The enzymes’ ability to bind to RBC was evaluated by western blotting, and routine blood typing and fluorescence activated cell sorting was used to evaluate B/A to O conversion efficiency. Results The A to O conversion efficiency in glucose buffer was similar to that in glycine buffer with the same dose (>0.06 mg/mL pRBC). B to O conversion efficiency in glucose buffer was also similar to that in glycine buffer with the same dose (>0.005 mg/mL pRBC). Most enzymes could bind with RBC in glycine or glucose buffer, but few enzymes could bind with RBC in PBS, PCS, or normal saline. Conclusion These results indicate that 5% glucose solution provides a suitable condition for enzymolysis, especially for enzymes combining with RBC. Meanwhile, the conversion efficiency of A/B to O was similar in glucose buffer and glycine buffer. Moreover, 5% glucose solution has been used for years in venous transfusion, it is safe for humans and its cost is lower. Our results do, therefore, suggest that 5% glucose solution could become a novel suitable buffer for A/B to O blood group conversion. PMID:24333060

  12. Indicators: Salinity

    EPA Pesticide Factsheets

    Salinity is the dissolved salt content of a body of water. Excess salinity, due to evaporation, water withdrawal, wastewater discharge, and other sources, is a chemical sterssor that can be toxic for aquatic environments.

  13. Salinization of groundwater around underground LPG storage caverns, Korea : statistical interpretation

    NASA Astrophysics Data System (ADS)

    Lee, J.; Chang, H.

    2001-12-01

    In this research, we investigate the reciprocal influence between groundwater flow and its salinization occurred in two underground cavern sites, using major ion chemistry, PCA for chemical analysis data, and cross-correlation for various hydraulic data. The study areas are two underground LPG storage facilities constructed in South Sea coast, Yosu, and West Sea coastal regions, Pyeongtaek, Korea. Considerably high concentration of major cations and anions of groundwaters at both sites showed brackish or saline water types. In Yosu site, some great chemical difference of groundwater samples between rainy and dry season was caused by temporal intrusion of high-saline water into propane and butane cavern zone, but not in Pyeongtaek site. Cl/Br ratios and δ 18O- δ D distribution for tracing of salinization source water in both sites revealed that two kind of saline water (seawater and halite-dissolved solution) could influence the groundwater salinization in Yosu site, whereas only seawater intrusion could affect the groundwater chemistry of the observation wells in Pyeongtaek site. PCA performed by 8 and 10 chemical ions as statistical variables in both sites showed that intensive intrusion of seawater through butane cavern was occurred at Yosu site while seawater-groundwater mixing was observed at some observation wells located in the marginal part of Pyeongtaek site. Cross-correlation results revealed that the positive relationship between hydraulic head and cavern operating pressure was far more conspicuous at propane cavern zone in both sites (65 ~90% of correlation coefficients). According to the cross-correlation results of Yosu site, small change of head could provoke massive influx of halite-dissolved solution from surface through vertically developed fracture networks. However in Pyeongtaek site, the pressure-sensitive observation wells are not completely consistent with seawater-mixed wells, and the hydraulic change of heads at these wells related to the

  14. Etched FBG coated with polyimide for simultaneous detection the salinity and temperature

    NASA Astrophysics Data System (ADS)

    Luo, Dong; Ma, Jianxun; Ibrahim, Zainah; Ismail, Zubaidah

    2017-06-01

    In marine environment, concrete structures can corrode because of the PH alkalinity of concrete paste; and the salinity PH is heavily related with the concentration of salt in aqueous solutions. In this study, an optical fiber salinity sensor is proposed on the basis of an etched FBG (EFBG) coated with a layer of polyimide. Chemical etching is employed to reduce the diameter of FBG and to excite Cladding Mode Resonance Wavelengths (CMRWs). CMRW and Fundamental Mode Resonance Wavelength (FMRW) can be used to measure the Refractive index (RI) and temperature of salinity. The proposed sensor is then characterized with a matrix equation. Experimental results show that FMRW and 5th CMRW have the detection sensitivities of 15.407 and 125.92 nm/RIU for RI and 0.0312 and 0.0435 nm/°C for temperature, respectively. The proposed sensor can measure salinity and temperature simultaneously.

  15. Degradation of bare and silanized silicon wafer surfaces by constituents of biological fluids.

    PubMed

    Dekeyser, C M; Buron, C C; Derclaye, S R; Jonas, A M; Marchand-Brynaert, J; Rouxhet, P G

    2012-07-15

    The 24 h stability of bare silicon wafers as such or silanized with CH(3)O-(CH(2)-CH(2)-O)(n)-C(3)H(6)-trichlorosilane (n=6-9) was investigated in water, NaCl, phosphate and carbonate solutions, and in phosphate buffered saline (PBS) at 37 °C (close to biological conditions regarding temperature, high ionic strength, and pH). The resulting surfaces were analyzed using ellipsometry, X-ray Reflectometry (XRR), X-ray Photoelectron Spectroscopy (XPS), and Atomic Force Microscopy (AFM). Incubation of the silanized wafers in phosphate solution and PBS provokes a detachment of the silane layer. This is due to a hydrolysis of Si-O bonds which is favored by the action of phosphate, also responsible for a corrosion of non-silanized wafers. The surface alteration (detachment of silane layer and corrosion of the non-silanized wafer) is also important with carbonate solution, due to a higher pH (8.3). The protection of the silicon oxide layer brought by silane against the action of the salts is noticeable for phosphate but not for carbonate. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. 75 FR 44264 - Federal Management Regulation; FMR Bulletin PBS-2010-B4; Redesignation of Federal Building

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-28

    ... Management Regulation; FMR Bulletin PBS-2010-B4; Redesignation of Federal Building AGENCY: Public Buildings... announces the redesignation of a Federal building. DATES: Expiration Date: This bulletin expires December 31, 2010. However, the building redesignation announced by this bulletin will remain in effect until...

  17. Effects of salinity and the extent of water on supercritical CO2-induced phlogopite dissolution and secondary mineral formation.

    PubMed

    Shao, Hongbo; Ray, Jessica R; Jun, Young-Shin

    2011-02-15

    To ensure the viability of geologic CO2 sequestration (GCS), we need a holistic understanding of reactions at supercritical CO2 (scCO2)-saline water-rock interfaces and the environmental factors affecting these interactions. This research investigated the effects of salinity and the extent of water on the dissolution and surface morphological changes of phlogopite [KMg2.87Si3.07Al1.23O10(F,OH)2], a model clay mineral in potential GCS sites. Salinity enhanced the dissolution of phlogopite and affected the location, shape, size, and phase of secondary minerals. In low salinity solutions, nanoscale particles of secondary minerals formed much faster, and there were more nanoparticles than in high salinity solutions. The effect of water extent was investigated by comparing scCO2-H2O(g)-phlogopite and scCO2-H2O(l)-phlogopite interactions. Experimental results suggested that the presence of a thin water film adsorbed on the phlogopite surface caused the formation of dissolution pits and a surface coating of secondary mineral phases that could change the physical properties of rocks. These results provide new information for understanding reactions at scCO2-saline water-rock interfaces in deep saline aquifers and will help design secure and environmentally sustainable CO2 sequestration projects.

  18. Saline infusion sonohysterography.

    PubMed

    2004-01-01

    Saline infusion sonohysterography consists of ultrasonographic imaging of the uterus and uterocervical cavity, using real-time ultrasonography during injection of sterile saline into the uterus. When properly performed, saline infusion sonohysterography can provide information about the uterus and endometrium. The most common indication for sonohysterography is abnormal uterine bleeding. sonohysterography should not be performed in a woman who is pregnant or could be pregnant or in a woman with a pelvic infection or unexplained pelvic tenderness. Physicians who perform or supervise diagnostic saline infusion sonohysterograpy should have training, experience, and demonstrated competence in gynecologic ultrasonography and saline infusion sonohysterography. Portions of this document were developed jointly with the American College of Radiology and the American Institute of Ultrasound in Medicine.

  19. Culture Shock: A Teacher's Guide To Accompany the Four-Part PBS Series Premiering January 2000.

    ERIC Educational Resources Information Center

    Jaffee, Cyrisse, Ed.; Sharma, Amina, Ed.

    This teacher's guide accompanies the four videos ("Born to Trouble: Adventures of Huckleberry Finn"; "The Shock of the Nude: Manet's Olympia"; "Hollywood Censored: Movies, Morality and the Production Code"; and "The Devil's Music: 1920s Jazz") of the PBS "Culture Shock" series. The guide suggests that the videos could be used in the…

  20. Molecular diversity analysis of Tetradium ruticarpum (WuZhuYu) in China based on inter-primer binding site (iPBS) markers and inter-simple sequence repeat (ISSR) markers.

    PubMed

    Xu, Jing-Yuan; Zhu, Yan; Yi, Ze; Wu, Gang; Xie, Guo-Yong; Qin, Min-Jian

    2018-01-01

    "Wu zhu yu", which is obtained from the dried unripe fruits of Tetradium ruticarpum (A. Jussieu) T. G. Hartley, has been used as a traditional Chinese medicine for treatment of headaches, abdominal colic, and hypertension for thousands of years. The present study was designed to assess the molecular genetic diversity among 25 collected accessions of T. ruticarpum (Wu zhu yu in Chinese) from different areas of China, based on inter-primer binding site (iPBS) markers and inter-simple sequence repeat (ISSR) markers. Thirteen ISSR primers generated 151 amplification bands, of which 130 were polymorphic. Out of 165 bands that were amplified using 10 iPBS primers, 152 were polymorphic. The iPBS markers displayed a higher proportion of polymorphic loci (PPL = 92.5%) than the ISSR markers (PPL = 84.9%). The results showed that T. ruticarpum possessed high loci polymorphism and genetic differentiation occurred in this plant. The combined data of iPBS and ISSR markers scored on 25 accessions produced five clusters that approximately matched the geographic distribution of the species. The results indicated that both iPBS and ISSR markers were reliable and effective tools for analyzing the genetic diversity in T. ruticarpum. Copyright © 2018 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  1. The effect of a new formaldehyde-free binder on the dissolution rate of glass wool fibre in physiological saline solution.

    PubMed

    Potter, Russell M; Olang, Nassreen

    2013-04-12

    The in-vitro dissolution rate of fibres is a good predictor of the in-vivo behavior and potential health effects of inhaled fibres. This study examines the effect of a new formaldehyde-free carbohydrate-polycarboxylic acid binder on the in-vitro dissolution rate of biosoluble glass fibres. Dissolution rate measurements in pH 7.4 physiological saline solution show that the presence of the binder on wool insulation glass fibres has no effect on their dissolution. There is no measurable difference between the dissolution rates of continuous draw fibres before and after binder was applied by dipping. Nor is there a measurable difference between the dissolution rates of a production glass wool sample with binder and that same sample after removal of the binder by low-temperature ashing. Morphological examination shows that swelling of the binder in the solution is at least partially responsible for the development of open channels around the glass-binder interface early in the dissolution. These channels allow fluid to reach the entire glass surface under the binder coating. There is no evidence of any delay in the dissolution rate as a result of the binder coating.

  2. The effect of a new formaldehyde-free binder on the dissolution rate of glass wool fibre in physiological saline solution

    PubMed Central

    2013-01-01

    The in-vitro dissolution rate of fibres is a good predictor of the in-vivo behavior and potential health effects of inhaled fibres. This study examines the effect of a new formaldehyde-free carbohydrate-polycarboxylic acid binder on the in-vitro dissolution rate of biosoluble glass fibres. Dissolution rate measurements in pH 7.4 physiological saline solution show that the presence of the binder on wool insulation glass fibres has no effect on their dissolution. There is no measurable difference between the dissolution rates of continuous draw fibres before and after binder was applied by dipping. Nor is there a measurable difference between the dissolution rates of a production glass wool sample with binder and that same sample after removal of the binder by low-temperature ashing. Morphological examination shows that swelling of the binder in the solution is at least partially responsible for the development of open channels around the glass-binder interface early in the dissolution. These channels allow fluid to reach the entire glass surface under the binder coating. There is no evidence of any delay in the dissolution rate as a result of the binder coating. PMID:23587247

  3. Enhanced Performance of PbS-quantum-dot-sensitized Solar Cells via Optimizing Precursor Solution and Electrolytes

    NASA Astrophysics Data System (ADS)

    Tian, Jianjun; Shen, Ting; Liu, Xiaoguang; Fei, Chengbin; Lv, Lili; Cao, Guozhong

    2016-03-01

    This work reports a PbS-quantum-dot-sensitized solar cell (QDSC) with power conversion efficiency (PCE) of 4%. PbS quantum dots (QDs) were grown on mesoporous TiO2 film using a successive ion layer absorption and reaction (SILAR) method. The growth of QDs was found to be profoundly affected by the concentration of the precursor solution. At low concentrations, the rate-limiting factor of the crystal growth was the adsorption of the precursor ions, and the surface growth of the crystal became the limiting factor in the high concentration solution. The optimal concentration of precursor solution with respect to the quantity and size of synthesized QDs was 0.06 M. To further increase the performance of QDSCs, the 30% deionized water of polysulfide electrolyte was replaced with methanol to improve the wettability and permeability of electrolytes in the TiO2 film, which accelerated the redox couple diffusion in the electrolyte solution and improved charge transfer at the interfaces between photoanodes and electrolytes. The stability of PbS QDs in the electrolyte was also improved by methanol to reduce the charge recombination and prolong the electron lifetime. As a result, the PCE of QDSC was increased to 4.01%.

  4. Enhanced Performance of PbS-quantum-dot-sensitized Solar Cells via Optimizing Precursor Solution and Electrolytes.

    PubMed

    Tian, Jianjun; Shen, Ting; Liu, Xiaoguang; Fei, Chengbin; Lv, Lili; Cao, Guozhong

    2016-03-15

    This work reports a PbS-quantum-dot-sensitized solar cell (QDSC) with power conversion efficiency (PCE) of 4%. PbS quantum dots (QDs) were grown on mesoporous TiO2 film using a successive ion layer absorption and reaction (SILAR) method. The growth of QDs was found to be profoundly affected by the concentration of the precursor solution. At low concentrations, the rate-limiting factor of the crystal growth was the adsorption of the precursor ions, and the surface growth of the crystal became the limiting factor in the high concentration solution. The optimal concentration of precursor solution with respect to the quantity and size of synthesized QDs was 0.06 M. To further increase the performance of QDSCs, the 30% deionized water of polysulfide electrolyte was replaced with methanol to improve the wettability and permeability of electrolytes in the TiO2 film, which accelerated the redox couple diffusion in the electrolyte solution and improved charge transfer at the interfaces between photoanodes and electrolytes. The stability of PbS QDs in the electrolyte was also improved by methanol to reduce the charge recombination and prolong the electron lifetime. As a result, the PCE of QDSC was increased to 4.01%.

  5. The growth of epitaxial single crystal PbS 1-xSe x films by hot wall evaporation

    NASA Astrophysics Data System (ADS)

    Neuelmann, R.; Marino, A.; Reichelt, K.

    1983-12-01

    Heteroepitaxial films of semiconducting PbS 1- xSe x on rock salt and mica substrates have been prepared and studied. The films have good crystalline perfection but have low electron mobilities, probably due to deviations from stoichiometry.

  6. Comparison of Irrigation Solutions and Devices in a Contaminated Musculoskeletal Wound Survival Model

    DTIC Science & Technology

    2009-01-01

    greatest reduction was seen with castile soap, which lowered the photon count to 13% of the pretreatment level. This was followed by benzalkonium chloride ...castile soap was significantly greater than that with the normal saline solution (p = 0.0069), while the reductions with benzalkonium chloride (p...the goats were assigned to four treatment groups: normal saline solution, bacitracin solution, castile soap, and benzalkonium chloride . All wounds

  7. Impact of the water salinity on the hydraulic conductivity of fen peat

    NASA Astrophysics Data System (ADS)

    Gosch, Lennart; Janssen, Manon; Lennartz, Bernd

    2017-04-01

    Coastal peatlands represent an interface between marine and terrestrial ecosystems; their hydrology is affected by salt and fresh water inflow alike. Previous studies on bog peat have shown that pore water salinity can have an impact on the saturated hydraulic conductivity (Ks) of peat because of chemical pore dilation effects. In this ongoing study, we are aiming at quantifying the impact of higher salinities (up to 3.5 %) on Ks of fen peat to get a better understanding of the water and solute exchange between coastal peatlands and the adjacent sea. Two approaches differing in measurement duration employing a constant-head upward-flow permeameter were conducted. At first, Ks was measured at an initial salinity for several hours before the salinity was abruptly increased and the measurement continued. In the second approach, Ks was measured for 15 min at the salt content observed during sampling. Then, samples were completely (de)salinized via diffusion for several days/weeks before a comparison measurement was carried out. The results for degraded fen peats show a decrease of Ks during long-term measurements which does not depend on the water salinity. A slow, diffusion-controlled change in salinity does not modify the overall outcome that the duration of measurements has a stronger impact on Ks than the salinity. Further experiments will show if fen peat soils differing in their state of degradation exhibit a different behavior. A preliminary conclusion is that salinity might have a less important effect on hydraulic properties of fen peat than it was observed for bog peat.

  8. Results from the first fully automated PBS-mask process and pelliclization

    NASA Astrophysics Data System (ADS)

    Oelmann, Andreas B.; Unger, Gerd M.

    1994-02-01

    Automation is widely discussed in IC- and mask-manufacturing and partially realized everywhere. The idea for the automation goes back to 1978, when it turned out that the operators for the then newly installed PBS-process-line (the first in Europe) should be trained to behave like robots for particle reduction gaining lower defect densities on the masks. More than this goal has been achieved. It turned out recently, that the automation with its dedicated work routes and detailed documentation of every lot (individual mask or reticle) made it easy to obtain the CEEC certificate which includes ISO 9001.

  9. Physical characteristics of commercial and home-made nasal lavage solutions.

    PubMed

    Lilic, N; Waldvogel-Thurlow, S; Douglas, R G

    2014-01-01

    Nasal saline lavage forms a cornerstone of chronic rhinosinusitis management. A number of saline lavage recipes and products are currently available but little is known of their relative physical characteristics. To determine the osmolarity and pH of nasal lavage solutions, both commercial preparations and home-made recipes, and to determine the reproducibility of saline solution preparation. Five home-made recipes and two commercial products were prepared in triplicate and analysed. Eight consecutive clinic patients prepared a commercial product and 11 prepared a home-made recipe, and the osmolarity and pH were measured. The osmolarity of the solutions varied widely, from 140 to 788 mmol/l and the pH varied from 7.88 to 8.50. The commercial and home-made solutions had similar reproducibility when prepared by patients. Some recipes were markedly hypo-osmolar and some were hyper-osmolar. All were slightly alkaline. The home-made recipes had similar physical characteristics and reproducibility to commercial preparations.

  10. The importance of extracellular speciation and corrosion of copper nanoparticles on lung cell membrane integrity.

    PubMed

    Hedberg, Jonas; Karlsson, Hanna L; Hedberg, Yolanda; Blomberg, Eva; Odnevall Wallinder, Inger

    2016-05-01

    Copper nanoparticles (Cu NPs) are increasingly used in various biologically relevant applications and products, e.g., due to their antimicrobial and catalytic properties. This inevitably demands for an improved understanding on their interactions and potential toxic effects on humans. The aim of this study was to investigate the corrosion of copper nanoparticles in various biological media and to elucidate the speciation of released copper in solution. Furthermore, reactive oxygen species (ROS) generation and lung cell (A549 type II) membrane damage induced by Cu NPs in the various media were studied. The used biological media of different complexity are of relevance for nanotoxicological studies: Dulbecco's modified eagle medium (DMEM), DMEM(+) (includes fetal bovine serum), phosphate buffered saline (PBS), and PBS+histidine. The results show that both copper release and corrosion are enhanced in DMEM(+), DMEM, and PBS+histidine compared with PBS alone. Speciation results show that essentially no free copper ions are present in the released fraction of Cu NPs in neither DMEM(+), DMEM nor histidine, while labile Cu complexes form in PBS. The Cu NPs were substantially more membrane reactive in PBS compared to the other media and the NPs caused larger effects compared to the same mass of Cu ions. Similarly, the Cu NPs caused much more ROS generation compared to the released fraction only. Taken together, the results suggest that membrane damage and ROS formation are stronger induced by Cu NPs and by free or labile Cu ions/complexes compared with Cu bound to biomolecules. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  11. A prospective randomized trial of two solutions for intrapartum amnioinfusion: effects on fetal electrolytes, osmolality, and acid-base status.

    PubMed

    Pressman, E K; Blakemore, K J

    1996-10-01

    Our purpose was to compare the effects of intrapartum amnioinfusion with normal saline solution versus lactated Ringer's solution plus physiologic glucose on neonatal electrolytes and acid-base balance. Patients undergoing amnioinfusion for obstetric indications were randomized to receive normal saline solution or lactated Ringer's solution plus physiologic glucose at standardized amnioinfusion rates. Data were collected prospectively on maternal demographics, course of labor, and maternal and neonatal outcome. Arterial cord blood was obtained for analysis of electrolytes, glucose, osmolality, lactic acid, and blood gases. Control subjects with normal fetal heart rate patterns, and clear amniotic fluid not receiving amnioinfusion were studied concurrently. Data were collected on 59 patients (21 normal saline solution, 18 lactated Ringer's solution plus physiologic glucose, and 20 controls). Maternal demographics, course of labor, and neonatal outcome were similar in all three groups. Cesarean sections were performed more often in the amnioinfusion groups (33.3% for normal saline solution, 38.9% for lactated Ringer's solution plus physiologic glucose) than in the control group (5.0%), p < 0.05. Cord arterial electrolytes, glucose, osmolality, lactic acid, and blood gases were not altered by amnioinfusion with either solution. Intrapartum amnioinfusion with normal saline solution or lactated Ringer's solution plus physiologic glucose has no effect on neonatal electrolytes or acid-base balance.

  12. Biological conversion of anglesite (PbSO(4)) and lead waste from spent car batteries to galena (PbS).

    PubMed

    Weijma, Jan; De Hoop, Klaas; Bosma, Wobby; Dijkman, Henk

    2002-01-01

    Lead paste, a solid mixture containing PbSO(4), PbO(2), PbO/Pb(OH)(2) precipitate, and elemental Pb, is one of the main waste fractions from spent car batteries. Biological sulfidation represents a new process for recovery of lead from this waste. In this process the lead salts in lead paste are converted to galena (PbS) by sulfate-reducing bacteria. This paper investigates a continuous process for sulfidation of anglesite (PbSO(4)), the main constituent of lead paste, and lead paste, consisting of a laboratory-scale gas-lift bioreactor to which a slurry of anglesite or lead paste was supplied. Sulfate or elemental sulfur was added as an additional sulfur source. Hydrogen gas served as an electron donor for the biological reduction of sulfate and elemental sulfur to sulfide by sulfate- and sulfur-reducing bacteria. Anglesite was almost completely converted to galena at a loading rate of 19 kg of PbSO(4) m(-)(3) day(-)(1), producing a sludge of which the crystalline lead phases consisted of >98% PbS (galena) and 1-2% elemental Pb. With lead paste, stable sulfidation rates of up to 17 kg of lead paste m(-)(3) day(-)(1) were demonstrated, producing a sludge of which the crystalline lead phases consisted of an estimated >96% PbS, 1-2% elemental Pb, and 1-2% PbO(2).

  13. Control of Energy Flow Dynamics between Tetracene Ligands and PbS Quantum Dots by Size Tuning and Ligand Coverage

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kroupa, Daniel M.; Arias, Dylan H.; Blackburn, Jeffrey L.

    We have prepared a series of samples with the ligand 6,13-bistri(iso-propyl)silylethynyl tetracene 2-carboxylic acid (TIPS-Tc-COOH) attached to PbS quantum dot (QD) samples of three different sizes in order to monitor and control the extent and time scales of energy flow after photoexcitation. Fast energy transfer (~1 ps) to the PbS QD occurs upon direct excitation of the ligand for all samples. The largest size QD maintains the microsecond exciton lifetime characteristic of the as-prepared oleate terminated PbS QDs. However, two smaller QD sizes with lowest exciton energies similar to or larger than the TIPS-Tc-COO- triplet energy undergo energy transfer betweenmore » QD core and ligand triplet on nanosecond to microsecond timescales. For the intermediate size QDs in particular, energy can be recycled many times between ligand and core, but the triplet remains the dominant excited species at long times, living for ~3 us for fully exchanged QDs and up to 30 us for partial ligand exchange, which is revealed as a method for controlling the triplet lifetime. A unique upconverted luminescence spectrum is observed that results from annihilation of triplets after exclusive excitation of the QD core.« less

  14. Control of Energy Flow Dynamics between Tetracene Ligands and PbS Quantum Dots by Size Tuning and Ligand Coverage

    DOE PAGES

    Kroupa, Daniel M.; Arias, Dylan H.; Blackburn, Jeffrey L.; ...

    2018-01-24

    We have prepared a series of samples with the ligand 6,13-bistri(iso-propyl)silylethynyl tetracene 2-carboxylic acid (TIPS-Tc-COOH) attached to PbS quantum dot (QD) samples of three different sizes in order to monitor and control the extent and time scales of energy flow after photoexcitation. Fast energy transfer (~1 ps) to the PbS QD occurs upon direct excitation of the ligand for all samples. The largest size QD maintains the microsecond exciton lifetime characteristic of the as-prepared oleate terminated PbS QDs. However, two smaller QD sizes with lowest exciton energies similar to or larger than the TIPS-Tc-COO- triplet energy undergo energy transfer betweenmore » QD core and ligand triplet on nanosecond to microsecond timescales. For the intermediate size QDs in particular, energy can be recycled many times between ligand and core, but the triplet remains the dominant excited species at long times, living for ~3 us for fully exchanged QDs and up to 30 us for partial ligand exchange, which is revealed as a method for controlling the triplet lifetime. A unique upconverted luminescence spectrum is observed that results from annihilation of triplets after exclusive excitation of the QD core.« less

  15. DEVELOPMENT OF BIOMARKER OF EXPOSURE TO VIRAL PATHOGENS

    EPA Science Inventory

    Interferon gamma (IFN-γ) was selected as a biomarker for a viral exposure study. Twelve-week-old BALB/c mice were intraperitoneally injected with 0.2ml of 104 PFU/ml of coxsackievirus B3 or B4 diluted in phosphate-buffered saline (PBS). Control mice were injected with PBS on...

  16. An SFG study of interfacial amino acids at the hydrophilic SiO2 and hydrophobic deuterated polystyrene surfaces.

    PubMed

    Holinga, George J; York, Roger L; Onorato, Robert M; Thompson, Christopher M; Webb, Nic E; Yoon, Alfred P; Somorjai, Gabor A

    2011-04-27

    Sum frequency generation (SFG) vibrational spectroscopy was employed to characterize the interfacial structure of eight individual amino acids--L-phenylalanine, L-leucine, glycine, L-lysine, L-arginine, L-cysteine, L-alanine, and L-proline--in aqueous solution adsorbed at model hydrophilic and hydrophobic surfaces. Specifically, SFG vibrational spectra were obtained for the amino acids at the solid-liquid interface between both hydrophobic d(8)-polystyrene (d(8)-PS) and SiO(2) model surfaces and phosphate buffered saline (PBS) at pH 7.4. At the hydrophobic d(8)-PS surface, seven of the amino acids solutions investigated showed clear and identifiable C-H vibrational modes, with the exception being l-alanine. In the SFG spectra obtained at the hydrophilic SiO(2) surface, no C-H vibrational modes were observed from any of the amino acids studied. However, it was confirmed by quartz crystal microbalance that amino acids do adsorb to the SiO(2) interface, and the amino acid solutions were found to have a detectable and widely varying influence on the magnitude of SFG signal from water at the SiO(2)/PBS interface. This study provides the first known SFG spectra of several individual amino acids in aqueous solution at the solid-liquid interface and under physiological conditions.

  17. Tribological and Rheological Properties of a Synovial Fluid Model

    NASA Astrophysics Data System (ADS)

    Klossner, Rebecca; Liang, Jing; Krause, Wendy

    2010-03-01

    Hyaluronic acid (HA) and the plasma proteins, albumin and globulins, are the most abundant macromolecules in synovial fluid, the fluid that lubricates freely moving joints. In previous studies, bovine synovial fluid, a synovial fluid model (SFM) and albumin in phosphate buffered saline (PBS) were observed to be rheopectic---viscosity increases over time under constant shear. Additionally, steady shear experiments have a strong shear history dependence in protein-containing solutions, whereas samples of HA in PBS behaved as a ``typical'' polyelectrolyte. The observed rheopexy and shear history dependence are indicative of structure building in solution, which is most likely caused by protein aggregation. The tribology of the SFM was also investigated using nanoindenter-based scratch tests. The coefficient of frictions (μ) between the diamond nanoindenter tip and a polyethylene surface was measured in the presence of the SFM and solutions with varied protein and HA concentrations. The lowest μ is observed in the SFM, which most closely mimics a healthy joint. Finally, an anti-inflammatory drug, hydroxychloroquine, was shown to inhibit protein interactions in the SFM in rheological studies, and thus the tribological response was examined. We hypothesize that the rheopectic behavior is important in lubrication regimes and therefore, the rheological and tribological properties of these solutions will be correlated.

  18. Impacts of gantry angle dependent scanning beam properties on proton PBS treatment

    NASA Astrophysics Data System (ADS)

    Lin, Yuting; Clasie, Benjamin; Lu, Hsiao-Ming; Flanz, Jacob; Shen, Tim; Jee, Kyung-Wook

    2017-01-01

    While proton beam models in treatment planning systems are generally assumed invariant with respect to the beam deliveries at different gantry angles. Physical properties of scanning pencil beams can change. The gantry angle dependent properties include the delivered charge to the monitor unit chamber, the spot position and the spot shape. The aim of this study is to investigate the extent of the changes and their dosimetric impacts using historical pencil beam scanning (PBS) treatment data. Online beam delivery records at the time of the patient-specific qualify assurance were retrospectively collected for a total of 34 PBS fields from 28 patients treated at our institution. For each field, proton beam properties at two different gantry angles (the planned and zero gantry angles) were extracted by a newly-developed machine log analysis method and used to reconstruct the delivered dose distributions in the cubic water phantom geometry. The reconstructed doses at the two different angles and a planar dose measurement by a 2D ion-chamber array were compared and the dosimetric impacts of the gantry angle dependency were accessed by a 3D γ-index analysis. In addition, the pencil beam spot size was independently characterized as a function of the gantry angle and the beam energy. The dosimetric effects of the perturbed beam shape were also investigated. Comparisons of spot-by-spot beam positions between both gantry angles show a mean deviation of 0.4 and 0.7 mm and a standard deviation of 0.3 and 0.6 mm for x and y directions, respectively. The delivered giga-protons per spot show a percent mean difference and a standard deviation of 0.01% and 0.3%, respectively, from each planned spot weight. These small deviations lead to an excellent agreement in dose comparisons with an average γ passing rate of 99.1%. When each calculation for both planned and zero gantry angles was compared to the measurement, a high correlation in γ values was also observed, also

  19. Salinity build-up in osmotic membrane bioreactors: Causes, impacts, and potential cures.

    PubMed

    Song, Xiaoye; Xie, Ming; Li, Yun; Li, Guoxue; Luo, Wenhai

    2018-06-01

    Osmotic membrane bioreactor (OMBR), which integrates forward osmosis (FO) with biological treatment, has been developed to advance wastewater treatment and reuse. OMBR is superior to conventional MBR, particularly in terms of higher effluent quality, lower membrane fouling propensity, and higher membrane fouling reversibility. Nevertheless, advancement and future deployment of OMBR are hindered by salinity build-up in the bioreactor (e.g., up to 50 mS/cm indicated by the mixed liquor conductivity), due to high salt rejection of the FO membrane and reverse diffusion of the draw solution. This review comprehensively elucidates the relative significance of these two mechanisms towards salinity build-up and its associated effects in OMBR operation. Recently proposed strategies to mitigate salinity build-up in OMBR are evaluated and compared to highlight their potential in practical applications. In addition, the complementarity of system optimization and modification to effectively manage salinity build-up are recommended for sustainable OMBR development. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. The effects of salinity and temperature shock on Kappaphycus alvarezii seaweed spores release

    NASA Astrophysics Data System (ADS)

    Harwinda, F. K.; Satyantini, W. H.; Masithah, E. W.

    2018-04-01

    One of the reproductive aspects of development step that is considered as the solution of this issue is seaweed sporulation technique through which is induced through salinity and temperature shock. This study aims to determine the effect of combination and interaction of salinity and temperature shock on the release of K. alvarezii spores in order to produce superior seeds. This research was conducted using Complete Randomized Design Factorial which consists of nine combinations of treatments and three replications. The used treatment in this study is the combination of different environmental factors such as salinity shock and temperature shock. The data were analyzed using ANOVA (Analysis of Variance) followed by Duncan Multiple Range Test. The results showed that salinity (31 ppt, 33 ppt, and 35 ppt) and temperature (30°C, 32°C, and 34°C). shock affected the osmoregulation system and the release of K. alvarezii spores. The salinity shock and temperature shock had interaction with K. alvarezii spore release on the sixth and seventh day with the best treatment at 32°C temperature and 31 ppt salinity and released 5413 cells/ml spores on the seventh day.

  1. Fabrication of PbS quantum dots and their applications in solar cells based on ZnO nanorod arrays

    NASA Astrophysics Data System (ADS)

    Kumar, Dinesh; Chaudhary, Sujeet; Pandya, Dinesh K.

    2018-05-01

    An efficient, inexpensive and large area scalable approach based on sol-gel technique is presented to fabricate quantum dots (QDs) of PbS. Size of the QDs is tuned by the varying the bath concentrations in the range of 50-200 mM. Transmission electron microscopy (TEM) studies confirm the growth of spherically shaped ˜5.6 nm QDs at 50 mM bath concentration. The optical bandgap of the QDs is found to be ˜0.9 eV and corresponds to the size obtained from TEM studies. ZnO/PbS solar cells are fabricated by sensitizing the ZnO nanorods with PbS QDs. The fabricated solar cells demonstrate the highest open circuit voltage ˜200 mV and short circuit current density ˜0.81 µA/cm2.

  2. Nucleation and growth of hydroxyapatite on arc-deposited TiO2 surfaces studied by quartz crystal microbalance with dissipation

    NASA Astrophysics Data System (ADS)

    Lilja, Mirjam; Butt, Umer; Shen, Zhijian; Bjöörn, Dorota

    2013-11-01

    Understanding of nucleation and growth kinetics of biomimetically deposited hydroxyapatite (HA) on crystalline TiO2 surfaces is important with respect to the application and performance of HA as functional implant coatings. Arc-evaporation was used to deposit TiO2 coatings dominated by anatase phase, rutile phase or their mixtures. Subsequent formation of HA from phosphate buffered saline solution (PBS) was investigated in real-time using in situ quartz crystal microbalance with dissipation technique (QCM-D). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were employed to characterize the presence, morphology and crystal structure of TiO2 coatings and the formed HA. Increasing temperature of the PBS, increasing flow rate and applying a higher ion concentration in solution were found to accelerate HA nucleation process and hence affect growth kinetics. Lower PBS temperature resulted in the formation of HA coatings with flake-like morphology and increasing HA porosity. All TiO2 coatings under study enabled HA formation at body temperature, while in contrast Ti reference surfaces only supported HA nucleation and growth at elevated temperatures. QCM-D technique is a powerful tool for studying the impact of process parameters during biomimetic coating deposition on coating structure evolution in real time and provides valuable information for understanding, optimizing as well as tailoring the biomimetic HA growth processes.

  3. Optical and electrical characterizations of a single step ion beam milling mesa devices of chloride passivated PbS colloidal quantum dots based film

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hechster, Elad, E-mail: elad.hechster@gmail.com; Sarusi, Gabby; Shapiro, Arthur

    Colloidal Quantum Dots (CQDs) are of increasing interest, thanks to their quantum size effect that gives rise to their usage in various applications, such as biological tagging, solar cells and as the sensitizing layer of night vision devices. Here, we analyze the optical absorbance of chloride passivated PbS CQDs as well as revealing a correlation between their photoluminescence and sizes distribution, using theoretical models and experimental results from the literature. Next, we calculate the CQDs resistivity as a film. Although resistivity can be calculated from sheet resistance measurement using four point probes, such measurement is usually carried-out on the layer’smore » surface that in most cases has dangling bonds and surface states, which might affect the charges flow and modify the resistivity. Therefore; our approach, which was applied in this work, is to extract the actual resistivity from measurements that are performed along the film’s thickness (z-direction). For this intent, we fabricated gold capped PbS mesas devices using a single step Ion Beam Milling (IBM) process where we milled the gold and the PbS film continually, and then measured the vertical resistance. Knowing the mesas’ dimensions, we calculate the resistivity. To the best of our knowledge, no previous work has extracted, vertically, the resistivity of chloride passivated PbS CQDs using the above method.« less

  4. Effect of salinity and temperature on treatment of concentrated wastewater from RO by FO-MD

    NASA Astrophysics Data System (ADS)

    Zhou, Yingru; Huang, Manhong; Deng, Qian

    2018-02-01

    In this study the appropriate temperature of the membrane distillation (MD) hot side (the permeation flux of MD was controlled by adjusting the hot side temperature) was selected according to the water flux of FO process so that the water transfer rate on both sides of FO and MD was consistent and the FO-MD process could be stable operation. When the salt concentration of feed solution was 30, 55, 80 and 100 g/L, the desalination rates changed little, which were 99.1%, 98.4%, 98.9% and 98.7%, respectively. The removal rate of COD was 93.8%, 94.2%, 91.6% and 92.7% which also changed little like the desalination rates. The removal rate of chromaticity increased with the increase of salinity, which attained 96.6%, 97.0%, 97.2% and 97.9%, respectively. This study proved that salinity of the feed solution affected little on the removal rate of contaminants but great on the water flux, with the increase of salinity from 30 to 100 g/L, the water flux was 6.05, 4.81, 4.33 and 3.87 LMH with the appropriate temperature (67.5±0.5, 64.5±0.5, 62.5±0.5 and 60.5±0.5 °C) of MD hot side. In a word, FO-MD was first used to treat the high salinity RO water with over 30 g/L total dissolved solids (TDS), FO-MD was a promising new process for high salinity wastewater treatment, and the hybrid system can solve the problem of lower draw solution concentration, and the high-quality production water will be obtained directly by this hybrid system with low membrane fouling tendency.

  5. In Vitro Quantified Determination of β-Amyloid 42 Peptides, a Biomarker of Neuro-Degenerative Disorders, in PBS and Human Serum Using a Simple, Cost-Effective Thin Gold Film Biosensor.

    PubMed

    Dai, Yifan; Molazemhosseini, Alireza; Liu, Chung Chiun

    2017-07-20

    A simple in vitro biosensor for the detection of β-amyloid 42 in phosphate-buffered saline (PBS) and undiluted human serum was fabricated and tested based on our platform sensor technology. The bio-recognition mechanism of this biosensor was based on the effect of the interaction between antibody and antigen of β-amyloid 42 to the redox couple probe of K₄Fe(CN)₆ and K₃Fe(CN)₆. Differential pulse voltammetry (DPV) served as the transduction mechanism measuring the current output derived from the redox coupling reaction. The biosensor was a three-electrode electrochemical system, and the working and counter electrodes were 50 nm thin gold film deposited by a sputtering technique. The reference electrode was a thick-film printed Ag/AgCl electrode. Laser ablation technique was used to define the size and structure of the biosensor. Cost-effective roll-to-roll manufacturing process was employed in the fabrication of the biosensor, making it simple and relatively inexpensive. Self-assembled monolayers (SAM) of 3-Mercaptopropionic acid (MPA) was employed to covalently immobilize the thiol group on the gold working electrode. A carbodiimide conjugation approach using N -(3-dimethylaminopropyl)- N '-ethylcarbodiimide hydrochloride (EDC) and N -hydroxysuccinimide (NHS) was undertaken for cross-linking antibody of β-amyloid 42 to the carboxylic groups on one end of the MPA. The antibody concentration of β-amyloid 42 used was 18.75 µg/mL. The concentration range of β-amyloid 42 in this study was from 0.0675 µg/mL to 0.5 µg/mL for both PBS and undiluted human serum. DPV measurements showed excellent response in this antigen concentration range. Interference study of this biosensor was carried out in the presence of Tau protein antigen. Excellent specificity of this β-amyloid 42 biosensor was demonstrated without interference from other species, such as T-tau protein.

  6. Salinity alters curcumin, essential oil and chlorophyll of turmeric (Curcuma longa L.).

    PubMed

    Mostajeran, A; Gholaminejad, A; Asghari, G

    2014-01-01

    Turmeric (Curcuma longa L.) is a perennial rhizomatous plant from the family of Zingibraceae, native in South Asia. The main components of turmeric are curcuminoids and essential oil which are responsible for turmeric characteristic such as odor and taste. Due to the large areas of saline land in Iran and less information related to cultivation of turmeric, in this research, the effect of salinity on growth, curcumin and essential oil of turmeric was evaluated. Rhizomes were planted in coco peat and perlite for germination. Then uniform germinated rhizomes transferred to hydroponic condition containing Hoagland's solution. Two months old plants were exposed to salinity (0, 20, 60 and 100 mM NaCl) for two months via hydroponic media using Hoagland's solution. Then dry weight of different plant parts, chlorophyll, curcumin and essential oil components of turmeric were determined. The result indicated that, dry weight reductions in 100 mM NaCl were 191%, 141%, 56%, 30% in leaf, pseudo-stem, root and rhizome, respectively (This is almost equal to 6.9, 2.87, 0.34 and 0.23 mg plant(-1) mM(-1)NaCl reduction of dry weight, respectively). The reductions in chlorophyll a and b are almost 3.32 and 0.79 μg/gFW respectively due to one unit addition of NaCl (P < 0.05). The addition of curcumin of rhizome for four months old plant versus three months were almost 5 fold for 0 mM NaCl and 2 fold for 100 mM NaCl due to one month of delay in harvest. Low salinity has positive effect in curcumin production but higher salinity (higher than 60 mM) had adverse effect and causes 24% reduction of curcumin compared to control plants. There were more para-cymene and terpineol in volatile oils of turmeric rhizome than the other components, most of the volatile oil compounds were unchanged or varied slightly as salinity changed.

  7. Salinity alters curcumin, essential oil and chlorophyll of turmeric (Curcuma longa L.)

    PubMed Central

    Mostajeran, A.; Gholaminejad, A.; Asghari, G.

    2014-01-01

    Turmeric (Curcuma longa L.) is a perennial rhizomatous plant from the family of Zingibraceae, native in South Asia. The main components of turmeric are curcuminoids and essential oil which are responsible for turmeric characteristic such as odor and taste. Due to the large areas of saline land in Iran and less information related to cultivation of turmeric, in this research, the effect of salinity on growth, curcumin and essential oil of turmeric was evaluated. Rhizomes were planted in coco peat and perlite for germination. Then uniform germinated rhizomes transferred to hydroponic condition containing Hoagland's solution. Two months old plants were exposed to salinity (0, 20, 60 and 100 mM NaCl) for two months via hydroponic media using Hoagland's solution. Then dry weight of different plant parts, chlorophyll, curcumin and essential oil components of turmeric were determined. The result indicated that, dry weight reductions in 100 mM NaCl were 191%, 141%, 56%, 30% in leaf, pseudo-stem, root and rhizome, respectively (This is almost equal to 6.9, 2.87, 0.34 and 0.23 mg plant-1 mM-1NaCl reduction of dry weight, respectively). The reductions in chlorophyll a and b are almost 3.32 and 0.79 μg/gFW respectively due to one unit addition of NaCl (P < 0.05). The addition of curcumin of rhizome for four months old plant versus three months were almost 5 fold for 0 mM NaCl and 2 fold for 100 mM NaCl due to one month of delay in harvest. Low salinity has positive effect in curcumin production but higher salinity (higher than 60 mM) had adverse effect and causes 24% reduction of curcumin compared to control plants. There were more para-cymene and terpineol in volatile oils of turmeric rhizome than the other components, most of the volatile oil compounds were unchanged or varied slightly as salinity changed. PMID:25598799

  8. Effect of Temperature, Light and Salinity on Seed Germination and Radicle Growth of the Geographically Widespread Halophyte Shrub Halocnemum strobilaceum

    PubMed Central

    Qu, Xiao-Xia; Huang, Zhen-Ying; Baskin, Jerry M.; Baskin, Carol C.

    2008-01-01

    Background and Aims The small leafy succulent shrub Halocnemum strobilaceum occurs in saline habitats from northern Africa and Mediterranean Europe to western Asia, and it is a dominant species in salt deserts such as those of north-west China. The effects of temperature, light/darkness and NaCl salinity were tested on seed germination, and the effects of salinity were tested on seed germination recovery, radicle growth and radicle elongation recovery, using seeds from north-west China; the results were compared with those previously reported on this species from ‘salt steppes’ in the Mediterranean region of Spain. Methods Seed germination was tested over a range of temperatures in light and in darkness and over a range of salinities at 25 °C in the light. Seeds that did not germinate in the NaCl solutions were tested for germination in deionized water. Seeds from which radicles had barely emerged in deionized water were transferred to NaCl solutions for 10 d and then back to deionized water for 10 d to test for radicle growth and recovery. Key Results Seeds germinated to higher percentages in light than in darkness and at high than at low temperatures. Germination percentages decreased with an increase in salinity from 0·1 to 0·75 m NaCl. Seeds that did not germinate in NaCl solutions did so after transfer to deionized water. Radicle elongation was increased by low salinity, and then it decreased with an increase in salinity, being completely inhibited by ≥2·0 m NaCl. Elongation of radicles from salt solutions <3·0 m resumed after seedlings were transferred to deionized water. Conclusions The seed and early seedling growth stages of the life cycle of H. strobilaceum are very salt tolerant, and their physiological responses differ somewhat between the Mediterranean ‘salt steppe’ of Spain and the inland cold salt desert of north-west China. PMID:17428834

  9. Fully Enzymatic Membraneless Glucose|Oxygen Fuel Cell That Provides 0.275 mA cm(-2) in 5 mM Glucose, Operates in Human Physiological Solutions, and Powers Transmission of Sensing Data.

    PubMed

    Ó Conghaile, Peter; Falk, Magnus; MacAodha, Domhnall; Yakovleva, Maria E; Gonaus, Christoph; Peterbauer, Clemens K; Gorton, Lo; Shleev, Sergey; Leech, Dónal

    2016-02-16

    Coimmobilization of pyranose dehydrogenase as an enzyme catalyst, osmium redox polymers [Os(4,4'-dimethoxy-2,2'-bipyridine)2(poly(vinylimidazole))10Cl](+) or [Os(4,4'-dimethyl-2,2'-bipyridine)2(poly(vinylimidazole))10Cl](+) as mediators, and carbon nanotube conductive scaffolds in films on graphite electrodes provides enzyme electrodes for glucose oxidation. The recombinant enzyme and a deglycosylated form, both expressed in Pichia pastoris, are investigated and compared as biocatalysts for glucose oxidation using flow injection amperometry and voltammetry. In the presence of 5 mM glucose in phosphate-buffered saline (PBS) (50 mM phosphate buffer solution, pH 7.4, with 150 mM NaCl), higher glucose oxidation current densities, 0.41 mA cm(-2), are obtained from enzyme electrodes containing the deglycosylated form of the enzyme. The optimized glucose-oxidizing anode, prepared using deglycosylated enzyme coimmobilized with [Os(4,4'-dimethyl-2,2'-bipyridine)2(poly(vinylimidazole))10Cl](+) and carbon nanotubes, was coupled with an oxygen-reducing bilirubin oxidase on gold nanoparticle dispersed on gold electrode as a biocathode to provide a membraneless fully enzymatic fuel cell. A maximum power density of 275 μW cm(-2) is obtained in 5 mM glucose in PBS, the highest to date under these conditions, providing sufficient power to enable wireless transmission of a signal to a data logger. When tested in whole human blood and unstimulated human saliva maximum power densities of 73 and 6 μW cm(-2) are obtained for the same fuel cell configuration, respectively.

  10. Case study on combined CO₂ sequestration and low-salinity water production potential in a shallow saline aquifer in Qatar.

    PubMed

    Ahmed, Tausif Khizar; Nasrabadi, Hadi

    2012-10-30

    CO₂ is one of the byproducts of natural gas production in Qatar. The high rate of natural gas production from Qatar's North Field (world's largest non-associated gas field) has led to the production of significant amounts of CO₂. The release of CO₂ into the atmosphere may be harmful from the perspective of global warming. In this work, we study the CO₂ sequestration potential in Qatar's Aruma aquifer. The Aruma aquifer is a saline aquifer in the southwest of Qatar. It occupies an area of approximately 1985 km₂ on land (16% of Qatar's total area). We have developed a compositional model for CO₂ sequestration in the Aruma aquifer on the basis of available log and flow test data. We suggest water production at some distance from the CO₂ injection wells as a possible way to control the pore pressure. This method increases the potential for safe sequestration of CO₂ in the aquifer without losing integrity of the caprock and without any CO₂ leakage. The water produced from this aquifer is considerably less saline than seawater and could be a good water source for the desalination process, which is currently the main source of water in Qatar. The outcome of the desalination process is water with higher salinity than the seawater that is currently discharged into the sea. This discharge can have negative long-term environmental effects. The water produced from the Aruma aquifer is considerably less saline than seawater and can be a partial solution to this problem. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Role of xylo-oligosaccharides in protection against salinity-induced adversities in Chinese cabbage.

    PubMed

    Chen, Weiwei; Guo, Chen; Hussain, Saddam; Zhu, Bingxin; Deng, Fang; Xue, Yan; Geng, Mingjian; Wu, Lishu

    2016-01-01

    Soil salinity is a stringent abiotic constraint limiting crop growth and productivity. The present study was carried out to appraise the role of xylo-oligosaccharides (XOSs) in improving the salinity tolerance of Chinese cabbage. Salinity stress (0.5% NaCl solution) and four levels (0, 40, 80, 120 mg L(-1)) of XOSs were imposed on 20-day-old plants cultured under controlled conditions. Salinity stress decreased the aboveground fresh biomass, photosynthesis, transpiration rate, stomatal conductance, internal CO2 concentration, water use efficiency, and chlorophyll contents but increased the stomatal limitation value of Chinese cabbage compared with control. Such physiological interferences, disturbances in plant water relations, and visually noticeable growth reductions in Chinese cabbage were significantly alleviated by the addition of XOSs under salinity stress. Under salinity stress, application of XOSs significantly enhanced the activities of enzymatic (superoxide dismutase, peroxidase, catalase) and non-enzymatic (ascorbate, carotene) antioxidants and reduced the malondialdehyde content in the leaves of Chinese cabbage. The XOS-applied plants under salinity stress also recorded higher soluble sugars, proline, and soluble protein content in their leaves. Exposure of salinity stress increased the ratio of Na(+)/K(+), Na(+)/Ca(2+), and Na(+)/Mg(2+) in shoot as well as root of Chinese cabbage, however, XOS application significantly reduced these ratios particularly in shoot. Lower levels of XOSs (40 or 80 mg L(-1)) were more effective for most of the studied attributes. The greater salinity tolerance and better growth in these treatments were related with enhanced antioxidative defense system, reduced lipid peroxidation, increased osmolyte accumulation, and maintenance of ionic balance.

  12. A comparison of equivolume, equiosmolar solutions of hypertonic saline and mannitol for brain relaxation during elective supratentorial craniotomy.

    PubMed

    Hernández-Palazón, Joaquín; Fuentes-García, Diego; Doménech-Asensi, Paloma; Piqueras-Pérez, Claudio; Falcón-Araña, Luis; Burguillos-López, Sebastián

    2016-01-01

    Hyperosmolar solutions have been used in neurosurgery to reduce brain volume and facilitate surgical exposure. The purpose of this study was to compare the effects of equivolume, equiosmolar solutions of mannitol and hypertonic saline (HS) on brain relaxation, intensive care unit (ICU) and hospital stay, postoperative outcomes and incidence of side-effects in patients undergoing elective supratentorial craniotomy. In a randomised, prospective, double-blind study, 60 patients undergoing elective supratentorial craniotomy were randomised 1:1 to receive 3 ml/kg of either 20% mannitol or 3% HS. The primary outcome was the surgical condition of the brain assessed by the neurosurgeon using a 4-point scale after opening the dura (1 = relaxed, 2 = satisfactory, 3 = firm and 4 = bulging). Secondary outcomes were electrolytes, blood gases, plasma osmolality and haemodynamic variables measured at 0 min, 30 min, 2 h and 6 h after infusion. Also, predefined postoperative complications, length of ICU and hospital stay were recorded. Appropriate statistical tests were used for comparison; p < 0.05 was considered significant. There was no difference in brain relaxation [mannitol, 1(1-3) versus HS, 1(1.4) points; p = 0.55]. Patients with brain midline shift showed a worse response to hyperosmolar solutions than those without midline shift: 37% versus 8%, respectively; OR = 6.6 (95% CI, 1.54-28.83); p = 0.006. Plasma osmolality increased during the study period (6 h) in both the groups (p < 0.05 compared with baseline). No significant differences in postoperative complications or length of ICU and hospital stay were observed between the groups. Single doses of 3 ml/kg of 20% mannitol and 3% HS are safe and effective for intraoperative brain debulking during elective supratentorial craniotomy, but less effective in patients with pre-existing mass effect and midline shift.

  13. Electron-Phonon Coupling and Resonant Relaxation from 1D and 1P States in PbS Quantum Dots.

    PubMed

    Kennehan, Eric R; Doucette, Grayson S; Marshall, Ashley R; Grieco, Christopher; Munson, Kyle T; Beard, Matthew C; Asbury, John B

    2018-05-31

    Observations of the hot-phonon bottleneck, which is predicted to slow the rate of hot carrier cooling in quantum confined nanocrystals, have been limited to date for reasons that are not fully understood. We used time-resolved infrared spectroscopy to directly measure higher energy intraband transitions in PbS colloidal quantum dots. Direct measurements of these intraband transitions permitted detailed analysis of the electronic overlap of the quantum confined states that may influence their relaxation processes. In smaller PbS nanocrystals, where the hot-phonon bottleneck is expected to be most pronounced, we found that relaxation of parity selection rules combined with stronger electron-phonon coupling led to greater spectral overlap of transitions among the quantum confined states. This created pathways for fast energy transfer and relaxation that may bypass the predicted hot-phonon bottleneck. In contrast, larger, but still quantum confined nanocrystals did not exhibit such relaxation of the parity selection rules and possessed narrower intraband states. These observations were consistent with slower relaxation dynamics that have been measured in larger quantum confined systems. These findings indicated that, at small radii, electron-phonon interactions overcome the advantageous increase in energetic separation of the electronic states for PbS quantum dots. Selection of appropriately sized quantum dots, which minimize spectral broadening due to electron-phonon interactions while maximizing electronic state separation, is necessary to observe the hot-phonon bottleneck. Such optimization may provide a framework for achieving efficient hot carrier collection and multiple exciton generation.

  14. Equal volumes of undiluted nalbuphine and lidocaine and normal diluted saline prevents nalbuphine-induced injection pain.

    PubMed

    Wang, Fu-Yuan; Shen, Ya-Chun; Chen, Mao-Kai; Chau, Siu-Wah; Ku, Chia-Ling; Feng, Yu-Tung; Cheng, Kuang-I

    2011-12-01

    To determine if the intravenous co-administration of equal volumes of lidocaine and nalbuphine, with undiluted normal saline, prevents injection pain caused by nalbuphine. Eighty adult patients who were scheduled for minor surgeries under general anesthesia delivered via a laryngeal mask airway (LMA) were enrolled in this prospective, randomized, single-blind clinical trial. In the saline group (control) (n = 40), 1 mL (10 mg) nalbuphine was diluted with 9 mL normal saline. In the lidocaine group (experimental) (n = 40), 1 mL (10 mg) nalbuphine was diluted with 1 mL lidocaine (20 mg). The two respective nalbuphine solutions were injected into the cephalic vein at a rate of 20 mL/minute (0.33 mL/second). Pain scores were categorized into five grades. Pain responses upon intravenous injection of nalbuphine, site of cannulation, size of the catheter, and hemodynamic responses to nalbuphine were also recorded. Overall, the median pain score of patients in the lidocaine group was lower than that of the saline group (p < 0.001). In addition, the incidence of injection pain was lower in the lidocaine group than the saline group (2.5% vs. 30%, p = 0.001). A solution of equal volumes of lidocaine and nalbuphine can decrease intravenous nalbuphine-induced injection pain. Copyright © 2011. Published by Elsevier B.V.

  15. Evaporation of NaCl solution from porous media with mixed wettability

    NASA Astrophysics Data System (ADS)

    Bergstad, Mina; Shokri, Nima

    2016-05-01

    Evaporation of saline water from porous media is ubiquitous in many processes including soil salinization, crop production, and CO2 sequestration in deep saline acquirer. It is controlled by the transport properties of porous media, atmospheric conditions, and properties of the evaporating saline solution. In the present study, the effects of mixed wettability conditions on the general dynamics of water evaporation from porous media saturated with NaCl solution were investigated. To do so, we conducted a comprehensive series of evaporation experiments using sand mixtures containing different fractions of hydrophobic grains saturated with NaCl solutions. Our results showed that increasing fraction of hydrophobic grains in the mixed wettability sand pack had minor impact on the evaporative mass losses due to the presence of salt whose precipitation patterns were significantly influenced by the mixed wettability condition. Through macroscale and microscale investigations, we found formation of patchy efflorescence in the case of mixed wettability sand pack as opposed to crusty efflorescence in the case of completely hydrophilic porous media. Furthermore, the presence of salty water and hydrophobic grains in the sand pack significantly influenced the general dynamics and morphology of the receding drying front. Our results extend the understanding of the saline water evaporation from porous media with direct applications to various hydrological and engineering processes.

  16. Corneal epithelial cell biocompatibility to silicone hydrogel and conventional hydrogel contact lens packaging solutions

    PubMed Central

    Tanti, N.C.; Jones, L.; Sheardown, H.

    2010-01-01

    Purpose Although all contact lenses (CLs) are applied initially to the eye directly from a packaging solution, little is known about the effects of these solutions on human corneal epithelial cells (HCECs). Due to the porous nature of CL materials, they have the potential to sorb components of the packaging solution during storage, which could then be subsequently released upon insertion of the CL on the eye. The purpose of this study was to investigate the effect of various packaging solutions on HCECs, using an in vitro model. Methods An in vitro assay was developed whereby various silicone hydrogels and conventional, poly-2-hydroxyethylmethacrylate  (polyHEMA)-based lens materials were removed directly from their packaging and then incubated for up to 24 h with HCECs. The effect of the retained and released packaging solution components on HCECs was assessed by measuring cell viability, adhesion phenotype, and apoptosis. Results Incubation of HCECs with CLs stored in borate-buffered packaging solutions resulted in a significant reduction in cell viability. Adherent cells incubated with these CLs also exhibited reduced levels of β1 and α3 integrin. Soaking borate-buffered packaged CLs in PBS before cell incubation resolved viability and integrin expression in all cases, with the exception of galyfilcon A and balafilcon A, from which a 20% reduction in cell viability was still observed. In comparison, CLs stored in phosphate-buffered packaging solutions had cellular viability and expression of integrins similar to control cells (cells incubated in the absence of a lens). When incubated with cells at a 10% concentration in serum-free medium, borate-buffered packaging solutions and borate-containing saline (Unisol 4) significantly reduced cell viability and integrin expression. Neither caspase activation nor annexin V binding was observed on cells following exposure to borate buffer solution. However, a significant decrease in reactive oxygen species was observed

  17. A novel submucosal injection solution for endoscopic resection of large colorectal lesions: a randomized, double-blind trial.

    PubMed

    Repici, Alessandro; Wallace, Michael; Sharma, Prateek; Bhandari, Pradeep; Lollo, Gianluca; Maselli, Roberta; Hassan, Cesare; Rex, Douglas K

    2018-05-08

    SIC-8000 (Eleview) is a new FDA-approved solution for submucosal injection developed to provide long-lasting cushion to facilitate endoscopic resection maneuvers. Our aim was to compare the efficacy and safety of SIC-8000 with those of saline solution, when performing endoscopic mucosal resection (EMR) of large colorectal lesions. In a randomized double-blind trial, patients undergoing EMR for ≥20 mm colorectal non-pedunculated lesions were randomized in a 1:1 ratio between SIC-8000 and saline solution as control solution in 5 tertiary centers. Endoscopists and patients were blinded to the type of submucosal solution used. Total volume to complete EMR and per lesion size and time of resection were primary end-points, whereas the Sydney Resection Quotient (SRQ), as well as other EMR outcomes, and the rate of adverse events were secondary. A 30-day telephone follow up was performed. An alpha level <0.05 was considered as statistically significant (NCT 02654418). Of the 327 patients screened, 226 (mean age: 66±10; males: 56%) were enrolled in the study and randomized between the 2 submucosal agents. Of these, 211 patients (mean size of the lesions 33±13 mm; I-s: 36%; proximal colon: 74%) entered in the final analysis (SIC-8000: 102; saline solution: 109). EMR was complete in all cases. The total volume needed for EMR was significantly less in the SIC-8000 arm compared with saline solution (16.1±9.8 mL vs 31.6±32.0 mL; p<0.001). This corresponded to an average volume per lesion size of 0.5±0.3 mL/mm and 0.9±0.6 mL/mm with SIC-8000 and saline solution, respectively, (p<0.001). The mean time to completely resect the lesion tended to be lower with SIC-8000 as compared with saline solution (19.1±16.8 minutes vs 29.7±68.9 minutes; p=0.1). The SRQ was significantly higher with SIC-8000 as compared with saline solution (10.3±8.1 vs 8.0±5.7; p=0.04) with a trend for a lower number of resected pieces (5.7±6.0 vs 6.5±5.04; p=0.052) and a higher rate of en bloc

  18. Chlorophyll Fluorescence as a Possible Tool for Salinity Tolerance Screening in Barley (Hordeum vulgare L.).

    PubMed Central

    Belkhodja, R.; Morales, F.; Abadia, A.; Gomez-Aparisi, J.; Abadia, J.

    1994-01-01

    The application of chlorophyll fluorescence measurements to screening barley (Hordeum vulgare L.) genotypes for salinity tolerance has been investigated. Excised barley leaves were cut under water and incubated with the cut end immersed in water or in a 100-mM NaCl solution, either in the dark or in high light. Changes in rapid fluorescence kinetics occurred in excised barley leaves exposed to the saline solution only when the incubation was carried out in the presence of high light. Fluorescence changes consisted of decreases in the variable to maximum fluorescence ratio and in increases in the relative proportion of variable fluorescence leading to point I in the Kautsky fluorescence induction curve. These relative increases in fluorescence at point I appeared to arise from a delayed plastoquinone reoxidation in the dark, since they disappeared after short, far-red illumination, which is known to excite photosystem I preferentially. We show that a significant correlation existed between some fluorescence parameters, measured after a combined salt and high-light treatment, and other independent measurements of salinity tolerance. These results suggest that chlorophyll fluorescence, and especially the relative fluorescence at point I in the Kautsky fluorescence induction curve, could be used for the screening of barley genotypes for salinity tolerance. PMID:12232117

  19. Microbially Mediated Plant Salt Tolerance and Microbiome-based Solutions for Saline Agriculture.

    PubMed

    Qin, Yuan; Druzhinina, Irina S; Pan, Xueyu; Yuan, Zhilin

    2016-11-15

    Soil salinization adversely affects plant growth and has become one of the major limiting factors for crop productivity worldwide. The conventional approach, breeding salt-tolerant plant cultivars, has often failed to efficiently alleviate the situation. In contrast, the use of a diverse array of microorganisms harbored by plants has attracted increasing attention because of the remarkable beneficial effects of microorganisms on plants. Multiple advanced '-omics' technologies have enabled us to gain insights into the structure and function of plant-associated microbes. In this review, we first focus on microbe-mediated plant salt tolerance, in particular on the physiological and molecular mechanisms underlying root-microbe symbiosis. Unfortunately, when introducing such microbes as single strains to soils, they are often ineffective in improving plant growth and stress tolerance, largely due to competition with native soil microbial communities and limited colonization efficiency. Rapid progress in rhizosphere microbiome research has revived the belief that plants may benefit more from association with interacting, diverse microbial communities (microbiome) than from individual members in a community. Understanding how a microbiome assembles in the continuous compartments (endosphere, rhizoplane, and rhizosphere) will assist in predicting a subset of core or minimal microbiome and thus facilitate synthetic re-construction of microbial communities and their functional complementarity and synergistic effects. These developments will open a new avenue for capitalizing on the cultivable microbiome to strengthen plant salt tolerance and thus to refine agricultural practices and production under saline conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. De Novo Transcriptional Analysis of Alfalfa in Response to Saline-Alkaline Stress.

    PubMed

    An, Yi-Min; Song, Li-Li; Liu, Ying-Rui; Shu, Yong-Jun; Guo, Chang-Hong

    2016-01-01

    Saline-alkaline stress, caused by high levels of harmful carbonate salts and high soil pH, is a major abiotic stress that affects crop productivity. Alfalfa is a widely cultivated perennial forage legume with some tolerance to biotic and abiotic stresses, especially to saline-alkaline stress. To elucidate the mechanism underlying plant saline-alkaline tolerance, we conducted transcriptome analysis of whole alfalfa seedlings treated with saline-alkaline solutions for 0 day (control), 1 day (short-term treatment), and 7 days (long-term treatment) using ion torrent sequencing technology. A transcriptome database dataset of 53,853 unigenes was generated, and 2,286 and 2,233 genes were differentially expressed in the short-term and long-term treatment, respectively. Gene ontology analysis revealed 14 highly enriched pathways and demonstrated the differential response of metabolic pathways between the short-term and long-term treatment. The expression levels of 109 and 96 transcription factors were significantly altered significantly after 1 day and 7 days of treatment, respectively. Specific responses of peroxidase, flavonoids, and the light pathway component indicated that the antioxidant capacity was one of the central mechanisms of saline-alkaline stress tolerance response in alfalfa. Among the 18 differentially expressed genes examined by real time PCR, the expression levels of eight genes, including inositol transporter, DNA binding protein, raffinose synthase, ferritin, aldo/keto reductase, glutathione S-transferase, xyloglucan endotrans glucosylase, and a NAC transcription factor, exhibited different patterns in response to saline and alkaline stress. The expression levels of the NAC transcription factor and glutathione S-transferase were altered significantly under saline stress and saline-alkaline stress; they were upregulated under saline-alkaline stress and downregulated under salt stress. Physiology assays showed an increased concentration of reactive oxygen

  1. De Novo Transcriptional Analysis of Alfalfa in Response to Saline-Alkaline Stress

    PubMed Central

    An, Yi-Min; Song, Li-Li; Liu, Ying-Rui; Shu, Yong-Jun; Guo, Chang-Hong

    2016-01-01

    Saline-alkaline stress, caused by high levels of harmful carbonate salts and high soil pH, is a major abiotic stress that affects crop productivity. Alfalfa is a widely cultivated perennial forage legume with some tolerance to biotic and abiotic stresses, especially to saline-alkaline stress. To elucidate the mechanism underlying plant saline-alkaline tolerance, we conducted transcriptome analysis of whole alfalfa seedlings treated with saline-alkaline solutions for 0 day (control), 1 day (short-term treatment), and 7 days (long-term treatment) using ion torrent sequencing technology. A transcriptome database dataset of 53,853 unigenes was generated, and 2,286 and 2,233 genes were differentially expressed in the short-term and long-term treatment, respectively. Gene ontology analysis revealed 14 highly enriched pathways and demonstrated the differential response of metabolic pathways between the short-term and long-term treatment. The expression levels of 109 and 96 transcription factors were significantly altered significantly after 1 day and 7 days of treatment, respectively. Specific responses of peroxidase, flavonoids, and the light pathway component indicated that the antioxidant capacity was one of the central mechanisms of saline-alkaline stress tolerance response in alfalfa. Among the 18 differentially expressed genes examined by real time PCR, the expression levels of eight genes, including inositol transporter, DNA binding protein, raffinose synthase, ferritin, aldo/keto reductase, glutathione S-transferase, xyloglucan endotrans glucosylase, and a NAC transcription factor, exhibited different patterns in response to saline and alkaline stress. The expression levels of the NAC transcription factor and glutathione S-transferase were altered significantly under saline stress and saline-alkaline stress; they were upregulated under saline-alkaline stress and downregulated under salt stress. Physiology assays showed an increased concentration of reactive oxygen

  2. AND logic-like pH- and light-dual controlled drug delivery by surface modified mesoporous silica nanoparticles.

    PubMed

    Zhao, Junwei; He, Zhaoshuai; Li, Biao; Cheng, Tanyu; Liu, Guohua

    2017-04-01

    Recently, the controlled drug delivery system has become a potential platform for biomedical application. Herein, we developed a pH and light-dual controlled cargo release system exhibiting AND logic based on MCM-41 mesoporous silica nanoparticles, which was surface modified using β-cyclodextrin (β-CD) with imine bond and azobenzene derivative. The complex of β-CD and azobenzene derivative effectively blocked the cargo delivery in pH=7.0 phosphate buffered saline (PBS) solution without 365nm UV light irradiation. The cargo was fully released when both factors of acidic environment (pH=5.0 PBS) and 365nm UV light irradiation were satisfied, meanwhile only very little cargo was delivered if one factor was satisfied. The result also demonstrates that the opening/closing of the gate and the release of the cargo in small portions can be controlled. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. ‘Green’-synthesized near-infrared PbS quantum dots with silica-PEG dual-layer coating: ultrastable and biocompatible optical probes for in vivo animal imaging

    NASA Astrophysics Data System (ADS)

    Wang, D.; Qian, J.; Cai, F.; He, S.; Han, S.; Mu, Y.

    2012-06-01

    In this paper, PbS semiconductor quantum dots (QDs) with near-infrared (NIR) photoluminescence were synthesized in oleic acid and paraffin liquid mixture by using an easily handled and ‘green’ approach. Surface functionalization of the QDs was accomplished with a silica and polyethylene glycol (PEG) phospholipid dual-layer coating and the excellent chemical stability of the nanoparticles is demonstrated. We then successfully applied the ultrastable PbS QDs to in vivo sentinel lymph node (SLN) mapping of mice. Histological analyses were also carried out to ensure that the intravenously injected nanoparticles did not produce any toxicity to the organism of mice. These experimental results suggested that our ultrastable NIR PbS QDs can serve as biocompatible and efficient probes for in vivo optical bioimaging and has great potentials for disease diagnosis and clinical therapies in the future.

  4. [Effect of compound hypertonic saline solution on septic rats].

    PubMed

    Dong, Fang; Xu, Liang; Xu, Gang; Wang, Huabing; Lu, Huizhi; Cai, Liping

    2015-01-01

    To study the effect of compound hypertonic saline solution ( HSD ) on sepsis. 133 male Wistar rats were divided into four groups, sham operation group ( n = 15 ), cecal ligation and puncture ( CLP ) group ( n = 45 ), CLP plus normal saline ( NS ) group ( n = 45 ), and CLP plus HSD group ( n = 28 ). A rat model of sepsis was reproduced by CLP, and the rats in sham operation group received celiotomy without ligation and puncture. All rats in four groups received subcutaneous injection of 30 mL/kg 0.9% sodium chloride after laparotomy. The rats in CLP plus NS group and CLP plus HSD group received infusion of 5 mL/kg 0.9% sodium chloride or 7.5% sodium chloride/6% dextran post CLP via jugular vein for 3 hours, with the infusion rate of 0.4 mL×kg(-1)×min(-1). The survival rate of each group was observed 9 hours and 18 hours after laparotomy. Mean arterial pressure ( MAP ) at 0, 9, 18 hours were monitored. Blood specimens were collected from all rats 0, 9 and 18 hours after laparotomy, respectively, for measurement of the plasma levels of tumor necrosis factor-α ( TNF-α), interleukin-1β ( IL-1β ), and procalcitonin ( PCT ). The rats were all sacrificed, and their lung tissues were harvested for the neutrophil count in bronchoalveolar lavage fluid ( BALF ), myeloperoxidase ( MPO ) activity in lung tissue, wet/dry weight ratio ( W/D ) of lung, and pathological changes in lung tissue. There was no death in the sham operation group. The survival rates at 9 hours and 18 hours were 62.2% and 31.1% in the CLP group, 57.8% and 35.6% in the CLP plus NS group, 85.7% and 64.3% in the CLP plus HSD group, and they were all significantly higher compared with those of the CLP group and the CLP plus NS group ( P<0.05 or P<0.01 ). MAP levels in the CLP group and the CLP plus NS group were significantly lower than those in sham operation group, and the plasma levels of TNF-α, IL-1β and PCT were significantly higher compared with those of sham operation group, while there was no

  5. RNS60, a charge-stabilized nanostructure saline alters Xenopus Laevis oocyte biophysical membrane properties by enhancing mitochondrial ATP production

    PubMed Central

    Choi, Soonwook; Yu, Eunah; Kim, Duk-Soo; Sugimori, Mutsuyuki; Llinás, Rodolfo R

    2015-01-01

    We have examined the effects of RNS60, a 0.9% saline containing charge-stabilized oxygen nanobubble-based structures. RNS60 is generated by subjecting normal saline to Taylor–Couette–Poiseuille (TCP) flow under elevated oxygen pressure. This study, implemented in Xenopus laevis oocytes, addresses both the electrophysiological membrane properties and parallel biological processes in the cytoplasm. Intracellular recordings from defolliculated X. laevis oocytes were implemented in: (1) air oxygenated standard Ringer's solution, (2) RNS60-based Ringer's solution, (3) RNS10.3 (TCP-modified saline without excess oxygen)-based Ringer's, and (4) ONS60 (saline containing high pressure oxygen without TCP modification)-based Ringer's. RNS60-based Ringer's solution induced membrane hyperpolarization from the resting membrane potential. This effect was prevented by: (1) ouabain (a blocker of the sodium/potassium ATPase), (2) rotenone (a mitochondrial electron transfer chain inhibitor preventing usable ATP synthesis), and (3) oligomycin A (an inhibitor of ATP synthase) indicating that RNS60 effects intracellular ATP levels. Increased intracellular ATP levels following RNS60 treatment were directly demonstrated using luciferin/luciferase photon emission. These results indicate that RNS60 alters intrinsic the electrophysiological properties of the X. laevis oocyte membrane by increasing mitochondrial-based ATP synthesis. Ultrastructural analysis of the oocyte cytoplasm demonstrated increased mitochondrial length in the presence of RNS60-based Ringer's solution. It is concluded that the biological properties of RNS60 relate to its ability to optimize ATP synthesis. PMID:25742953

  6. [Effect of hypertonic saline solution on the viscoelasticities of erythrocyte membrane in rats subjected to hemorrhagic shock].

    PubMed

    Zhou, X; Hu, D; Liu, L; Wu, Z; Qin, J; Cai, S

    2001-12-01

    We have studied the effect of hypertonic saline solution on the viscoelasticities of erythrocyte membrane in hemorrhage-shocked rats using micropippette aspiration technique. Wistar rats were randomly divided into three groups of 0.9% NaCl(NS), 7.5% NaCl (HS) and 5% NaCl-3.5% NaAc (HSA), respectively. The animals were bled to reach a mean arterial pressure of 5.3 kPa in 10 minutes and maintained in shock for 90 minutes. 4 ml/kg NS, HS and HSA was given intravenously and respectively in 5 minutes following hemorrhagic shock. The blood was collected to determine the viscoelasticities of erythrocyte membrane at baseline, shock and after treatment. The results showed that the elastic moduli and viscous coefficients of erythrocyte membrane were increased obviously following hemorrhagic shock. HS raised elastic moduli and reduced viscous coefficients significantly compared with NS after treatment. The elastic moduli and viscous coefficients of erythrocyte membrane were decreased remarkably in HSA group than in NS and HS group. These data suggested that HSA could improve the viscoelasticities of erythrocyte membrane significantly in rats subjected to hemorrhagic shock.

  7. Realization of PbS thin films by reactive evaporation technique for possible opto-electronic applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    A, Abhilash, E-mail: abhiltp@cusat.ac.in; Nair, Aparna S.; S, Rajasree

    2015-06-24

    Stoichiometric Lead sulphide (PbS) thin films were successfully prepared on glass substrates by reactive evaporation technique. Elemental evaporation of lead and sulphur taken in different sources onto substrates held at temperature of 400±5K employed in the present study. The structural as well as compositional studies compromises compound formation. Electrical transport properties and optical co-efficient were evaluated from appropriate characterization techniques.

  8. Improved electrical performance and bias stability of solution-processed active bilayer structure of indium zinc oxide based TFT.

    PubMed

    Seo, Jin-Suk; Bae, Byeong-Soo

    2014-09-10

    We fabricated active single- and bilayer structure thin film transistors (TFTs) with aluminum or gallium doped (IZO:Al or IZO:Ga) and undoped indium zinc oxide (IZO) thin film layers using an aqueous solution process. The electrical performance and bias stability of these active single- and bilayer structure TFTs were investigated and compared to reveal the effects of Al/Gal doping and bilayer structure. The single-layer structure IZO TFT shows a high mobility of 19 cm(2)/V · s with a poor positive bias stability (PBS) of ΔVT + 3.4 V. However, Al/Ga doped in IZO TFT reduced mobility to 8.5-9.9 cm(2)/V · s but improved PBS to ΔVT + 1.6-1.7 V due to the reduction of oxygen vacancy. Thus, it is found the bilayer structure TFTs with a combination of bottom- and top-layer compositions modify both the mobility and bias stability of the TFTs to be optimized. The bilayer structure TFT with an IZO:X bottom layer possess high mobility and an IZO bottom layer improves the PBS.

  9. Colorimetric detection of mercury(II) in a high-salinity solution using gold nanoparticles capped with 3-mercaptopropionate acid and adenosine monophosphate.

    PubMed

    Yu, Cheng-Ju; Tseng, Wei-Lung

    2008-11-04

    A new colorimetric sensor for sensing Hg2+ in a high-salinity solution has been developed using gold nanoparticles (AuNPs) decorated with 3-mercaptopropionate acid (MPA) and adenosine monophosphate (AMP). Because of the high negative charge density of AMP on each AuNP surface, MPA/AMP-capped AuNPs are well dispersed in a high-salt solution. In contrast, the aggregation of MPA-capped AuNPs was induced by sodium ions, which shield the negative charges of the carboxylic groups of MPA. Through the coordination between the carboxylic group of MPA and Hg2+, the selectivity of MPA/AMP-capped AuNPs for Hg2+ in a high-salt solution is remarkably high over that of the other metals without the addition of a masking agent or a change in the temperature. We have carefully investigated the effect of the AMP concentration on the stability and sensitivity of MPA/AMP-capped AuNPs. Under optimum conditions, the lowest detectable concentration of Hg2+ using this probe was 500 nM on the basis of the measurement of the ratio of absorption at 620 nm to that at 520 nm. The sensitivity to Hg2+ can be further improved by modifying the MPA/AMP-capped AuNPs with highly fluorescent rhodamine 6G (R6G). By monitoring the fluorescence enhancement, the lowest detectable concentration of Hg2+ using R6G/MPA/AMP-capped AuNPs was 50 nM.

  10. Ion association in water solution of soil and vadose zone of chestnut saline solonetz as a driver of terrestrial carbon sink

    NASA Astrophysics Data System (ADS)

    Batukaev, Abdul-Malik A.; Endovitsky, Anatoly P.; Andreev, Andrey G.; Kalinichenko, Valery P.; Minkina, Tatiana M.; Dikaev, Zaurbek S.; Mandzhieva, Saglara S.; Sushkova, Svetlana N.

    2016-03-01

    The assessment of soil and vadose zone as the drains for carbon sink and proper modeling of the effects and extremes of biogeochemical cycles in the terrestrial biosphere are the key components to understanding the carbon cycle, global climate system, and aquatic and terrestrial system uncertainties. Calcium carbonate equilibrium causes saturation of solution with CaCO3, and it determines its material composition, migration and accumulation of salts. In a solution electrically neutral ion pairs are formed: CaCO30, CaSO40, MgCO30, and MgSO40, as well as charged ion pairs CaHCO3+, MgHCO3+, NaCO3-, NaSO4-, CaOH+, and MgOH+. The calcium carbonate equilibrium algorithm, mathematical model and original software to calculate the real equilibrium forms of ions and to determine the nature of calcium carbonate balance in a solution were developed. This approach conducts the quantitative assessment of real ion forms of solution in solonetz soil and vadose zone of dry steppe taking into account the ion association at high ionic strength of saline soil solution. The concentrations of free and associated ion form were calculated according to analytical ion concentration in real solution. In the iteration procedure, the equations were used to find the following: ion material balance, a linear interpolation of equilibrium constants, a method of ionic pairs, the laws of initial concentration preservation, operating masses of equilibrium system, and the concentration constants of ion pair dissociation. The coefficient of ion association γe was determined as the ratio of ions free form to analytical content of ion γe = Cass/Can. Depending on soil and vadose zone layer, concentration and composition of solution in the ionic pair's form are 11-52 % Ca2+; 22.2-54.6 % Mg2+; 1.1-10.5 % Na+; 3.7-23.8 HCO3-, 23.3-61.6 % SO42-, and up to 85.7 % CO32-. The carbonate system of soil and vadose zone water solution helps to explain the evolution of salted soils, vadose and saturation zones, and

  11. Polyamidoamine dendrimer hydrogel for enhanced delivery of antiglaucoma drugs.

    PubMed

    Holden, Christopher A; Tyagi, Puneet; Thakur, Ashish; Kadam, Rajendra; Jadhav, Gajanan; Kompella, Uday B; Yang, Hu

    2012-07-01

    Dendrimer hydrogel (DH), made from ultraviolet-cured polyamidoamine dendrimer G3.0 tethered with three polyethylene glycol (PEG, 12,000 Da)-acrylate chains (8.1% w/v) in pH 7.4 phosphate buffered saline (PBS), was studied for the delivery of brimonidine (0.1% w/v) and timolol maleate (0.5% w/v), two antiglaucoma drugs. DH was found to be mucoadhesive to mucin particles and nontoxic to human corneal epithelial cells. DH increased the PBS solubility of brimonidine by 77.6% and sustained the in vitro release of both drugs over 56-72 hours. As compared to eye drop formulations (PBS-drug solutions), DH brought about substantially higher human corneal epithelial cells uptake and significantly increased bovine corneal transport for both drugs. DH increased timolol maleate uptake in bovine corneal epithelium, stroma, and endothelium by 0.4- to 4.6-fold. This work demonstrated that DH can enhance the delivery of antiglaucoma drugs in multiple aspects and represents a novel platform for ocular drug delivery. Dendrimer hydrogel was studied as agent for simultaneous delivery of two anti-glaucoma drugs, one hydrophobic and one hydrophilic. Superiority over standard PBS-based formulation was clearly demonstrated for both drugs. The work may be a novel platform for ocular drug delivery. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Effect of perfusion of bile salts solutions into the oesophagus of hiatal hernia patients and controls.

    PubMed Central

    Bachir, G S; Collis, J L

    1976-01-01

    Tests of the response to perfusion of the oesophagus were made in 54 patients divided into three groups. Group I consisted of patients with symptomatic hiatal hernia, group II hiatal hernia patients with peptic stricture, and group III normal individuals. Each individual oesophagus was perfused at a rate of 45-65 drops per minute over 25 minutes with six solutions: normal saline, N/10 HCl, taurine conjugates of bile salts in normal saline, taurine conjugates of bile salts in N/10 HCl, glycine conjugates of bile salts in normal saline, and taurine and glycine conjugates in a ratio of 1 to 2 in normal saline. It was found that acidified taurine solutions were more irritating than acid alone. With a 2mM/l solution of taurine in acid, symptoms are produced even in controls. With a 1 mM/l solution of the same conjugates, the majority of normal people feel slight heartburn or nothing, and therefore perfusion into the oesophagus of such a solution could be used as a test for oesophagitis. PMID:941112

  13. The occurrence and behavior of radium in saline formation water of the U.S. Gulf Coast region.

    USGS Publications Warehouse

    Kraemer, T.F.; Reid, D.F.

    1984-01-01

    Ra was measured in deep saline formation waters produced from a variety of US Gulf Coast subsurface environments, including oil and gas reservoirs, and water-producing geopressured aquifers. A strong positive correlation was found between formation-water salinity and Ra activity, resulting from the interaction of formation water with aquifer matrix. Ra isotopes enter the fluid phase after being produced by the decay of parent elements U and Th on and within the solid matrix. The processes believed to be primarily responsible for transfering Ra from matrix to formation water are chemical leaching and alpha -particle recoil. Factors controlling the observed salinity-Ra relationship may be one or a combination of the following: 1) ion exchange; 2) increased solubility of matrix silica surrounding Ra atoms, coupled with a salinity-controlled rate of re-equilibration of silica between solution and quartz grains; and 3) the equilibration of Ra in solution with detrital baryte within the aquifer. No difference was found in the brine-Ra relation in water produced from oil or gas wells and water produced from wells penetrating only water-bearing aquifers, although the relation was more highly correlated for water-bearing aquifers than hydrocarbon-containing reservoirs.-P.Br.

  14. Morphology and Kinetics of Growth of CaCO3 Precipitates Formed in Saline Water at 30°C

    NASA Astrophysics Data System (ADS)

    Sui, Xin; Wang, Baohui; Wu, Haiming

    2018-02-01

    The crystallization kinetics and morphology of CaCO3 crystals precipitated from the high salinity oilfield water were studied. The crystallization kinetics measurements show that nucleation and nuclei growth obey the first order reaction kinetics. The induction period of precipitation is extended in the high salinity solutions. Morphological studies show that impurity ions remain mostly in the solution phase instead of filling the CaCO3 crystal lattice. The morphology of CaCO3 precipitates can be changed from a smooth surface (calcite) to rough spheres (vaterite), and spindle rod bundles, or spherical, ellipsoid, flowers, plates and other shapes (aragonite).

  15. The Transcriptional Regulator, CosR, Controls Compatible Solute Biosynthesis and Transport, Motility and Biofilm Formation in Vibrio cholerae

    PubMed Central

    Shikuma, Nicholas J.; Davis, Kimberly R.; Fong, Jiunn N. C.; Yildiz, Fitnat H.

    2012-01-01

    SUMMARY Vibrio cholerae inhabits aquatic environments and colonizes the human digestive tract to cause the disease cholera. In these environments, V. cholerae copes with fluctuations in salinity and osmolarity by producing and transporting small, organic, highly soluble molecules called compatible solutes, which counteract extracellular osmotic pressure. Currently, it is unclear how V. cholerae regulates the expression of genes important for the biosynthesis or transport of compatible solutes in response to changing salinity or osmolarity conditions. Through a genome-wide transcriptional analysis of the salinity response of V. cholerae, we identified a transcriptional regulator we name CosR for compatible solute regulator. The expression of cosR is regulated by ionic strength and not osmolarity. A transcriptome analysis of a ΔcosR mutant revealed that CosR represses genes involved in ectoine biosynthesis and compatible solute transport in a salinity-dependent manner. When grown in salinities similar to estuarine environments, CosR activates biofilm formation and represses motility independently of its function as an ectoine regulator. This is the first study to characterize a compatible solute regulator in V. cholerae and couples the regulation of osmotic tolerance with biofilm formation and motility. PMID:22690884

  16. In-Fiber Optic Salinity Sensing: A Potential Application for Offshore Concrete Structure Protection.

    PubMed

    Luo, Dong; Li, Peng; Yue, Yanchao; Ma, Jianxun; Yang, Hangzhou

    2017-05-04

    The protection of concrete structures against corrosion in marine environments has always been a challenge due to the presence of a saline solution-A natural corrosive agent to the concrete paste and steel reinforcements. The concentration of salt is a key parameter influencing the rate of corrosion. In this paper, we propose an optical fiber-based salinity sensor based on bundled multimode plastic optical fiber (POF) as a sensor probe and a concave mirror as a reflector in conjunction with an intensity modulation technique. A refractive index (RI) sensing approach is analytically investigated and the findings are in agreement with the experimental results. A maximum sensitivity of 14,847.486/RIU can be achieved at RI = 1.3525. The proposed technique is suitable for in situ measurement and monitoring of salinity in liquid.

  17. Saline-water bioleaching of chalcopyrite with thermophilic, iron(II)- and sulfur-oxidizing microorganisms.

    PubMed

    Watling, Helen R; Collinson, David M; Corbett, Melissa K; Shiers, Denis W; Kaksonen, Anna H; Watkin, Elizabeth L J

    2016-09-01

    The application of thermoacidophiles for chalcopyrite (CuFeS2) bioleaching in hot, acidic, saline solution was investigated as a possible process route for rapid Cu extraction. The study comprised a discussion of protective mechanisms employed for the survival and/or adaptation of thermoacidophiles to osmotic stress, a compilation of chloride tolerances for three genera of thermoacidophiles applied in bioleaching and an experimental study of the activities of three species in a saline bioleaching system. The data showed that the oxidation rates of iron(II) and reduced inorganic sulfur compounds (tetrathionate) were reduced in the presence of chloride levels well below chloride concentrations in seawater, limiting the applicability of these microorganisms in the bioleaching of CuFeS2 in saline water. Copyright © 2016. Published by Elsevier Masson SAS.

  18. Additive effects of Na+ and Cl– ions on barley growth under salinity stress

    PubMed Central

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

    2011-01-01

    Soil salinity affects large areas of the world's cultivated land, causing significant reductions in crop yield. Despite the fact that most plants accumulate both sodium (Na+) and chloride (Cl–) ions in high concentrations in their shoot tissues when grown in saline soils, most research on salt tolerance in annual plants has focused on the toxic effects of Na+ accumulation. It has previously been suggested that Cl– toxicity may also be an important cause of growth reduction in barley plants. Here, the extent to which specific ion toxicities of Na+ and Cl– reduce the growth of barley grown in saline soils is shown under varying salinity treatments using four barley genotypes differing in their salt tolerance in solution and soil-based systems. High Na+, Cl–, and NaCl separately reduced the growth of barley, however, the reductions in growth and photosynthesis were greatest under NaCl stress and were mainly additive of the effects of Na+ and Cl– stress. The results demonstrated that Na+ and Cl– exclusion among barley genotypes are independent mechanisms and different genotypes expressed different combinations of the two mechanisms. High concentrations of Na+ reduced K+ and Ca2+ uptake and reduced photosynthesis mainly by reducing stomatal conductance. By comparison, high Cl– concentration reduced photosynthetic capacity due to non-stomatal effects: there was chlorophyll degradation, and a reduction in the actual quantum yield of PSII electron transport which was associated with both photochemical quenching and the efficiency of excitation energy capture. The results also showed that there are fundamental differences in salinity responses between soil and solution culture, and that the importance of the different mechanisms of salt damage varies according to the system under which the plants were grown. PMID:21273334

  19. Influence of Ophthalmic Solutions on Tear Components.

    PubMed

    Shigeyasu, Chika; Yamada, Masakazu; Akune, Yoko

    2016-11-01

    Tear fluids are a mixture of secretions derived from lacrimal glands, accessory lacrimal glands, conjunctiva, and meibomian glands. Compositional changes to tears occur in the normal state and during ocular surface disease, such as dry eye conditions. We have investigated compositional changes to tears after topical application of ophthalmic solutions, with regard to tear-specific proteins (secretory immunoglobulin A, lactoferrin, lipocalin-1, and lysozyme) and ocular surface mucin in normal and dry eye conditions using high-performance liquid chromatography. After application of saline solution (0.9% sodium chloride) in normal subjects, transient but significant decreases in all tear components were observed. The recovery of protein concentrations took up to 30 minutes and lasted longer when the saline solution was applied more frequently. When applying ophthalmic solutions, a balance between washout and dilutional effects should be considered in addition to the therapeutic effect. Investigation of the effect of diquafosol solution (3%) in normal subjects revealed a significant increase in sialic acid concentration, a marker of ocular mucin, at 5 minutes after application, whereas a significant decrease was observed with saline. This result indicates the accelerated secretion of mucin from ocular tissues induced by diquafosol. A clinical study to determine the efficacy of diquafosol in patients with dry eye revealed improvements in tear breakup time, keratoconjunctival staining scores, and Schirmer test score, accompanied by an increase in sialic acid concentration in tears. Investigating normal and dry eye conditions through tear analysis may clarify the pathophysiology of dry eye conditions and support the efficacy of treatments.

  20. The influence of closed brine pockets and permeable brine channels on the thermo-elastic properties of saline ice

    PubMed Central

    Lishman, Ben

    2017-01-01

    A model of the thermo-elastic behaviour of saline ice is formulated, and model solutions describing thermo-elastic waves (TEW) propagating into a half-space of the ice are investigated. The model is based on a proposal that saline ice is a matrix, which encompasses both closed brine pockets and permeable channels filled with brine. Experiments on the thermal expansion of saline ice samples, and on TEW in saline ice, have been performed in the cold laboratories of the University Centre in Svalbard and in University College London. The experimental data are compared with theoretical conclusions. The experimental data support our hypothesis that the brine in saline ice is divided between closed pockets and open, permeable channels. This article is part of the themed issue ‘Microdynamics of ice’. PMID:28025299

  1. Normal saline solution nasal-pharyngeal irrigation improves chronic cough associated with allergic rhinitis.

    PubMed

    Lin, Lin; Chen, Zhongchun; Cao, Yitan; Sun, Guangbin

    2017-03-01

    Upper airway inflammation is one of the most commonly identified causes of chronic cough, although the underlying mechanism is not clear. This study compared normal saline solution nasal-pharyngeal irrigation (NSNPI) and fluticasone propionate nasal spray (FPNS) treatment for chronic cough associated with allergic rhinitis (AR). Patients with suspected AR to house-dust mite were enrolled, and the symptom of cough was assessed by a cough symptom score and the Leicester Cough Questionnaire, and cough response to capsaicin was evaluated. AR was assessed by using the visual analog scale (VAS) and the Mini Juniper Rhinoconjunctivitis Quality of Life Questionnaire (MiniRQLQ). Mediators, including histamine, leukotriene C4, and prostaglandin D2, and the major basic protein from nasal lavage fluid (NLF) were examined. The patients were treated with NSNPI (the NSNPI group) or FPNS (the FPNS group) for 30 days, after which they were reassessed. Forty-five of 50 patients completed this study. The scores of the cough symptom and the Leicester Cough Questionnaire, and the capsaicin cough threshold all improved statistically after NSNPI but did not change after FPNS. There were statistically significant changes in the evaluations of the MiniRQLQ and the mediators, including histamine and leukotriene C4, in the NLF in the NSNPI group. However, significant changes were found in the assessments of VAS, MiniRQLQ, and all above mediators including histamine, leukotriene C4, and prostaglandin D2, and the major basic protein in the NLF of the FPNS group. Furthermore, the assessments of VAS and all the mediators were reduced more in the FPNS group compared with those in the NSNPI group. The patients with suspected AR to house-dust mite reported a better relief of the cough symptom after 30 days of treatment with NSNPI compared with that after nasal corticosteroid.

  2. In Vivo and In Vitro Nitinol Corrosion Properties

    NASA Astrophysics Data System (ADS)

    Lonn, Melissa K.; Metcalf, Justin M.; Choules, Brian D.

    2015-09-01

    Regulatory authorities often require in vitro testing on medical devices prior to approval. Current standardized corrosion testing methods (ASTM F2129) require testing in a non-physiologic, de-oxygenated solution for a pre-exposure time of ≤1 h; however, no correlations between the prescribed simulated environment and whole blood conditions have been elucidated. This study compared open circuit potential (OCP), breakdown potentials (Eb), Eb - OCP, and cyclic polarization curves tested in vivo (OCP only) and in vitro in whole blood to those tested in phosphate-buffered saline (PBS). Two oxide thicknesses of Nitinol, two solution oxygen contents (deaerated and aerated solutions), and two pre-exposure durations (acute and chronic) were investigated. The in vitro OCP in whole blood was not significantly different than the in vivo OCP, suggesting that whole blood in vitro can be used to determine baseline corrosion behavior of medical implants. Eb - OCP tested per ASTM F2129 was comparable to acute whole blood and was conservative compared to chronic whole blood for both oxide thicknesses. However, OCP, Eb, and cyclic polarization curves were not always comparable to whole blood. Testing in aerated PBS achieved Eb, Eb - OCP, and cyclic polarization curves that were comparable to or more conservative than whole blood testing, regardless of pre-exposure duration and oxide thickness.

  3. Slime coating of kaolinite on chalcopyrite in saline water flotation

    NASA Astrophysics Data System (ADS)

    Li, Zhi-li; Rao, Feng; Song, Shao-xian; Li, Yan-mei; Liu, Wen-biao

    2018-05-01

    In saline water flotation, the salinity can cause a distinguishable slime coating of clay minerals on chalcopyrite particles through its effect on their electrical double layers in aqueous solutions. In this work, kaolinite was used as a representative clay mineral for studying slime coating during chalcopyrite flotation. The flotation of chalcopyrite in the presence and absence of kaolinite in tap water, seawater, and gypsum-saturated water and the stability of chalcopyrite and kaolinite particles in slurries are presented. Zeta-potential distributions and scanning electron microscopy images were used to characterize and explain the different slime coating degrees and the different flotation performances. Kaolinite particles induced slime coating on chalcopyrite surfaces and reduced chalcopyrite floatability to the greatest extent when the pH value was in the alkaline range. At 0.24wt% of kaolinite, the chalcopyrite floatability was depressed by more than 10% at alkaline pH levels in tap water. Salinity in seawater and gypsum-saturated water compressed the electrical double layers and resulted in extensive slime coating.

  4. An inorganic CO2 diffusion and dissolution process explains negative CO2 fluxes in saline/alkaline soils.

    PubMed

    Ma, Jie; Wang, Zhong-Yuan; Stevenson, Bryan A; Zheng, Xin-Jun; Li, Yan

    2013-01-01

    An 'anomalous' negative flux, in which carbon dioxide (CO2) enters rather than is released from the ground, was studied in a saline/alkaline soil. Soil sterilization disclosed an inorganic process of CO2 dissolution into (during the night) and out of (during the day) the soil solution, driven by variation in soil temperature. Experimental and modeling analysis revealed that pH and soil moisture were the most important determinants of the magnitude of this inorganic CO2 flux. In the extreme cases of air-dried saline/alkaline soils, this inorganic process was predominant. While the diurnal flux measured was zero sum, leaching of the dissolved inorganic carbon in the soil solution could potentially effect net carbon ecosystem exchange. This finding implies that an inorganic module should be incorporated when dealing with the CO2 flux of saline/alkaline land. Neglecting this inorganic flux may induce erroneous or misleading conclusions in interpreting CO2 fluxes of these ecosystems.

  5. An inorganic CO2 diffusion and dissolution process explains negative CO2 fluxes in saline/alkaline soils

    PubMed Central

    Ma, Jie; Wang, Zhong-Yuan; Stevenson, Bryan A.; Zheng, Xin-Jun; Li, Yan

    2013-01-01

    An ‘anomalous' negative flux, in which carbon dioxide (CO2) enters rather than is released from the ground, was studied in a saline/alkaline soil. Soil sterilization disclosed an inorganic process of CO2 dissolution into (during the night) and out of (during the day) the soil solution, driven by variation in soil temperature. Experimental and modeling analysis revealed that pH and soil moisture were the most important determinants of the magnitude of this inorganic CO2 flux. In the extreme cases of air-dried saline/alkaline soils, this inorganic process was predominant. While the diurnal flux measured was zero sum, leaching of the dissolved inorganic carbon in the soil solution could potentially effect net carbon ecosystem exchange. This finding implies that an inorganic module should be incorporated when dealing with the CO2 flux of saline/alkaline land. Neglecting this inorganic flux may induce erroneous or misleading conclusions in interpreting CO2 fluxes of these ecosystems. PMID:23778238

  6. The Photosynthesis, Na+/K+ Homeostasis and Osmotic Adjustment of Atriplex canescens in Response to Salinity

    PubMed Central

    Pan, Ya-Qing; Guo, Huan; Wang, Suo-Min; Zhao, Bingyu; Zhang, Jin-Lin; Ma, Qing; Yin, Hong-Ju; Bao, Ai-Ke

    2016-01-01

    Atriplex canescens (fourwing saltbush) is a C4 perennial fodder shrub with excellent resistance to salinity. However, the mechanisms underlying the salt tolerance in A. canescens are poorly understood. In this study, 5-weeks-old A. canescens seedlings were treated with various concentrations of external NaCl (0–400 mM). The results showed that the growth of A. canescens seedlings was significantly stimulated by moderate salinity (100 mM NaCl) and unaffected by high salinity (200 or 400 mM NaCl). Furthermore, A. canescens seedlings showed higher photosynthetic capacity under NaCl treatments (except for 100 mM NaCl treatment) with significant increases in net photosynthetic rate and water use efficiency. Under saline conditions, the A. canescens seedlings accumulated more Na+ in either plant tissues or salt bladders, and also retained relatively constant K+ in leaf tissues and bladders by enhancing the selective transport capacity for K+ over Na+ (ST value) from stem to leaf and from leaf to bladder. External NaCl treatments on A. canescens seedlings had no adverse impact on leaf relative water content, and this resulted from lower leaf osmotic potential under the salinity conditions. The contribution of Na+ to the leaf osmotic potential (Ψs) was sharply enhanced from 2% in control plants to 49% in plants subjected to 400 mM NaCl. However, the contribution of K+ to Ψs showed a significant decrease from 34% (control) to 9% under 400 mM NaCl. Interestingly, concentrations of betaine and free proline showed significant increase in the leaves of A. canescens seedlings, these compatible solutes presented up to 12% of contribution to Ψs under high salinity. These findings suggest that, under saline environments, A. canescens is able to enhance photosynthetic capacity, increase Na+ accumulation in tissues and salt bladders, maintain relative K+ homeostasis in leaves, and use inorganic ions and compatible solutes for osmotic adjustment which may contribute to the

  7. Influence of Soil Solution Salinity on Molybdenum Adsorption by Soils

    USDA-ARS?s Scientific Manuscript database

    Molybdenum (Mo) adsorption on five arid-zone soils from California was investigated as a function of equilibrium solution Mo concentration (0-30 mg L-1), solution pH (4-8), and electrical conductivity (EC = 0.3 or 8 dS m-1). Molybdenum adsorption decreased with increasing pH. An adsorption maximum...

  8. Development of an enzyme-linked immunosorbent assay for seven sulfonamide residues and investigation of matrix effects from different food samples.

    PubMed

    Zhang, Hongyan; Wang, Lei; Zhang, Yan; Fang, Guozhen; Zheng, Wenjie; Wang, Shuo

    2007-03-21

    Direct competitive enzyme-linked immunosorbent assays (ELISA) were developed to detect a broad range of sulfonamides in various matrices. Screening for this class of antibiotics in pig muscle, chicken muscle, fish, and egg extracts was accomplished by simple, rapid extraction methods carried out with only phosphate-buffered saline (PBS) buffer. Twenty milliliters of extract solution was added to 4 g of sample to extract the sulfonamide residues, and sample extracts diluted with assay buffer were directly analyzed by ELISA; matrix effects could be avoided with 1:5 dilution of pig muscle, chicken muscle, and egg extracts with PBS and 1:5 dilution of fish extract with 1% bovine serum albumin (BSA)-PBS. For liver sample, the extraction method was a little more complicated; 2 g of sample was added to 20 mL of ethanol, mixed, and then centrifuged. The solvent of 10 mL of the upper liquid was removed, and the residues were dissolved in 10 mL of PBS and then filtered; the filtrate was diluted two-fold with 0.5% BSA-PBS for ELISA. These common methods were able to detect seven sulfonamide residues such as sulfisozole, sulfathiazole, sufameter, sulfamethoxypyridazine, sulfapyridine, sulfamethizole, and sulfachlorpyridazine in pig muscle, liver, chicken muscle, egg, and fish. The assay's detection limits for these compounds were less than 100 microg kg-1. Various extraction methods were tested, and the average recovery (n=3) of 100 microg kg-1 for the matrices was found to range from 77.3 to 123.7%.

  9. The effect of PbS nanocrystal additives on the charge transfer state recombination in a bulk heterojunction blend

    NASA Astrophysics Data System (ADS)

    Abdu-Aguye, Mustapha; Protesescu, Loredana; Dirin, Dmitry N.; Kovalenko, Maksym V.; Loi, Maria Antonietta

    2018-05-01

    A persistent limitation of organic semiconductors is their low dielectric constant єr, which limits the performance of bulk heterojunction (BHJ) solar cells. One way to increase єr is to employ high-єr additives, such as PbS nanocrystals (QDs) to BHJ blends. In this work, we use the recombination of the interfacial charge transfer (CT) state as a means to study the effects of PbS nanocrystals on blends of a narrow bandgap copolymer: poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1- b;3,4-b']dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT), and phenyl-C61-butyric acid methyl ester (PCBM). We show that at low dilution levels (0.25% - 0.75% by weight), there is a decrease in the relative weight of the CT recombination lifetime (longer decay component); suggesting that there is an increase in the local єr of the ternary blend.

  10. Balanced Crystalloids versus Saline in the Intensive Care Unit. The SALT Randomized Trial.

    PubMed

    Semler, Matthew W; Wanderer, Jonathan P; Ehrenfeld, Jesse M; Stollings, Joanna L; Self, Wesley H; Siew, Edward D; Wang, Li; Byrne, Daniel W; Shaw, Andrew D; Bernard, Gordon R; Rice, Todd W

    2017-05-15

    Saline is the intravenous fluid most commonly administered to critically ill adults, but it may be associated with acute kidney injury and death. Whether use of balanced crystalloids rather than saline affects patient outcomes remains unknown. To pilot a cluster-randomized, multiple-crossover trial using software tools within the electronic health record to compare saline to balanced crystalloids. This was a cluster-randomized, multiple-crossover trial among 974 adults admitted to a tertiary medical intensive care unit from February 3, 2015 to May 31, 2015. The intravenous crystalloid used in the unit alternated monthly between saline (0.9% sodium chloride) and balanced crystalloids (lactated Ringer's solution or Plasma-Lyte A). Enrollment, fluid delivery, and data collection were performed using software tools within the electronic health record. The primary outcome was the difference between study groups in the proportion of isotonic crystalloid administered that was saline. The secondary outcome was major adverse kidney events within 30 days (MAKE30), a composite of death, dialysis, or persistent renal dysfunction. Patients assigned to saline (n = 454) and balanced crystalloids (n = 520) were similar at baseline and received similar volumes of crystalloid by 30 days (median [interquartile range]: 1,424 ml [500-3,377] vs. 1,617 ml [500-3,628]; P = 0.40). Saline made up a larger proportion of the isotonic crystalloid given in the saline group than in the balanced crystalloid group (91% vs. 21%; P < 0.001). MAKE30 did not differ between groups (24.7% vs. 24.6%; P = 0.98). An electronic health record-embedded, cluster-randomized, multiple-crossover trial comparing saline with balanced crystalloids can produce well-balanced study groups and separation in crystalloid receipt. Clinical trial registered with www.clinicaltrials.gov (NCT 02345486).

  11. Groundwater flow and solute transport at the Mourquong saline-water disposal basin, Murray Basin, southeastern Australia

    NASA Astrophysics Data System (ADS)

    Simmons, Craig; Narayan, Kumar; Woods, Juliette; Herczeg, Andrew

    2002-03-01

    Saline groundwater and drainage effluent from irrigation are commonly stored in some 200 natural and artificial saline-water disposal basins throughout the Murray-Darling Basin of Australia. Their impact on underlying aquifers and the River Murray, one of Australia's major water supplies, is of serious concern. In one such scheme, saline groundwater is pumped into Lake Mourquong, a natural groundwater discharge complex. The disposal basin is hydrodynamically restricted by low-permeability lacustrine clays, but there are vulnerable areas in the southeast where the clay is apparently missing. The extent of vertical and lateral leakage of basin brines and the processes controlling their migration are examined using (1) analyses of chloride and stable isotopes of water (2H/1H and 18O/16O) to infer mixing between regional groundwater and lake water, and (2) the variable-density groundwater flow and solute-transport code SUTRA. Hydrochemical results indicate that evaporated disposal water has moved at least 100 m in an easterly direction and that there is negligible movement of brines in a southerly direction towards the River Murray. The model is used to consider various management scenarios. Salt-load movement to the River Murray was highest in a "worst-case" scenario with irrigation employed between the basin and the River Murray. Present-day operating conditions lead to little, if any, direct movement of brine from the basin into the river. Résumé. Les eaux souterraines salées et les effluents de drainage de l'irrigation sont stockés dans environ 200 bassins naturels ou artificiels destinés à retenir les eaux salines dans tout le bassin de Murray-Darling, en Australie. Leur impact sur les aquifères sous-jacents et sur la rivière Murray, l'une des principales ressources en eau d'Australie, constitue un problème grave. Dans une telle situation, les eaux souterraines salines sont pompées dans le lac Mourquong, complexe dans lequel les nappes se d

  12. Leaf water relations and net gas exchange responses of salinized Carrizo citrange seedlings during drought stress and recovery.

    PubMed

    Pérez-Pérez, J G; Syvertsen, J P; Botía, P; García-Sánchez, F

    2007-08-01

    Since salinity and drought stress can occur together, an assessment was made of their interacting effects on leaf water relations, osmotic adjustment and net gas exchange in seedlings of the relatively chloride-sensitive Carrizo citrange, Citrus sinensis x Poncirus trifoliata. Plants were fertilized with nutrient solution with or without additional 100 mm NaCl (salt and no-salt treatments). After 7 d, half of the plants were drought stressed by withholding irrigation water for 10 d. Thus, there were four treatments: salinized and non-salinized plants under drought-stress or well-watered conditions. After the drought period, plants from all stressed treatments were re-watered with nutrient solution without salt for 8 d to study recovery. Leaf water relations, gas exchange parameters, chlorophyll fluorescence, proline, quaternary ammonium compounds and leaf and root concentrations of Cl(-) and Na(+) were measured. Salinity increased leaf Cl(-) and Na(+) concentrations and decreased osmotic potential (Psi(pi)) such that leaf relative water content (RWC) was maintained during drought stress. However, in non-salinized drought-stressed plants, osmotic adjustment did not occur and RWC decreased. The salinity-induced osmotic adjustment was not related to any accumulation of proline, quaternary ammonium compounds or soluble sugars. Net CO(2) assimilation rate (A(CO2)) was reduced in leaves from all stressed treatments but the mechanisms were different. In non-salinized drought-stressed plants, lower A(CO2) was related to low RWC, whereas in salinized plants decreased A(CO2) was related to high levels of leaf Cl(-) and Na(+). A(CO2) recovered after irrigation in all the treatments except in previously salinized drought-stressed leaves which had lower RWC and less chlorophyll but maintained high levels of Cl(-), Na(+) and quaternary ammonium compounds after recovery. High leaf levels of Cl(-) and Na(+) after recovery apparently came from the roots. Plants preconditioned by

  13. Light Scattering Characterization of Elastin-Like Polypeptide Trimer Micelles

    NASA Astrophysics Data System (ADS)

    Tsuper, Ilona; Terrano, Daniel; Maraschky, Adam; Holland, Nolan; Streletzky, Kiril

    The elastin-like polypeptides (ELP) nanoparticles are composed of three-armed star polypeptides connected by a negatively charged foldon. Each of the three arms extending from the foldon domain includes 20 repeats of the (GVGVP) amino acid sequence. The ELP polymer chains are soluble at room temperature and become insoluble at the transition temperature (close to 50 ° C), forming micelles. The size and shape of the micelle are dependent on the temperature and the pH of the solution, and on the concentration of the phosphate buffered saline (PBS). The depolarized dynamic light scattering (DDLS) was employed to study the structure and dynamics of micelles at 62 ° C. The solution was maintained at an approximate pH level of 7.3 - 7.5, while varying PBS concentration. At low salt concentrations (<15 mM), the micelle radius was about 10nm but not very reproducible on account of unstable pH levels arising from low buffer concentrations. At intermediate salt concentrations (15 - 60 mM), the system formed spherically-shaped micelles, exhibiting a steady growth in the hydrodynamic radius (Rh) from 10 to 21 nm, with increasing PBS concentration. Interestingly, higher salt concentrations (>60 mM) displayed an apparent elongation of the micelles evident by a significant VH signal, along with a surge in the apparent Rh. A model of micelle growth (and potential elongation) with increase in salt concentration is considered.

  14. Practical salinity management for leachate irrigation to poplar trees.

    PubMed

    Smesrud, Jason K; Duvendack, George D; Obereiner, James M; Jordahl, James L; Madison, Mark F

    2012-01-01

    fifteen year record of monitoring and operational data are presented that can be used by others in managing irrigation of saline water to poplar trees. When salinity is carefully managed, tree systems can help to provide sustainable leachate management solutions for landfills.

  15. Seasonal induced changes in spinach rhizosphere microbial community structure with varying salinity and drought.

    PubMed

    Mark Ibekwe, A; Ors, Selda; Ferreira, Jorge F S; Liu, Xuan; Suarez, Donald L

    2017-02-01

    Salinity is a common problem under irrigated agriculture, especially in low rainfall and high evaporative demand areas of southwestern United States and other semi-arid regions around the world. However, studies on salinity effects on soil microbial communities are relatively few while the effects of irrigation-induced salinity on soil chemical and physical properties and plant growth are well documented. In this study, we examined the effects of salinity, temperature, and temporal variability on soil and rhizosphere microbial communities in sand tanks irrigated with prepared solutions designed to simulate saline wastewater. Three sets of experiments with spinach (Spinacia oleracea L., cv. Racoon) were conducted under saline water during different time periods (early winter, late spring, and early summer). Bacterial 16S V4 rDNA region was amplified utilizing fusion primers designed against the surrounding conserved regions using MiSeq® Illumina sequencing platform. Across the two sample types, bacteria were relatively dominant among three phyla-the Proteobacteria, Cyanobacteria, and Bacteroidetes-accounted for 77.1% of taxa detected in the rhizosphere, while Proteobacteria, Bacteroidetes, and Actinobacteria accounted for 55.1% of taxa detected in soil. The results were analyzed using UniFrac coupled with principal coordinate analysis (PCoA) to compare diversity, abundance, community structure, and specific bacterial groups in soil and rhizosphere samples. Permutational analysis of variance (PERMANOVA) analysis showed that soil temperature (P=0.001), rhizosphere temperature (P=0.001), rhizosphere salinity (P=0.032), and evapotranspiration (P=0.002) significantly affected beta diversity of soil and rhizosphere microbial communities. Furthermore, salinity had marginal effects (P=0.078) on soil beta diversity. However, temporal variability differentially affected rhizosphere microbial communities irrigated with saline wastewater. Therefore, microbial communities in

  16. Hydrogen isotope response to changing salinity and rainfall in Australian mangroves.

    PubMed

    Ladd, S Nemiah; Sachs, Julian P

    2015-12-01

    Hydrogen isotope ratios ((2) H/(1) H, δ(2) H) of leaf waxes covary with those in precipitation and are therefore a useful paleohydrologic proxy. Mangroves are an exception to this relationship because their δ(2) H values are also influenced by salinity. The mechanisms underlying this response were investigated by measuring leaf lipid δ(2) H and leaf and xylem water δ(2) H and δ(18) O values from three mangrove species over 9.5 months in a subtropical Australian estuary. Net (2) H/(1) H fractionation between surface water and leaf lipids decreased by 0.5-1.0‰ ppt(-1) for n-alkanes and 0.4-0.8‰ ppt(-1) for isoprenoids. Xylem water was (2) H depleted relative to surface water, reflecting (2) H discrimination of 4-10‰ during water uptake at all salinities and opportunistic uptake of freshwater at high salinity. However, leaf water (2) H enrichment relative to estuary water was insensitive to salinity and identical for all species. Therefore, variations in leaf and xylem water δ(2) H values cannot explain the salinity-dependent (2) H depletion in leaf lipids, nor the 30‰ range in leaf lipid δ(2) H values among species. Biochemical changes in direct response to salt stress, such as increased compatible solute production or preferential use of stored carbohydrates, and/or the timing of lipid production and subsequent turnover rates, are more likely causes. © 2015 John Wiley & Sons Ltd.

  17. Salinity stress inhibits bean leaf expansion by reducing turgor, not wall extensibility

    NASA Technical Reports Server (NTRS)

    Neumann, P. M.; Van Volkenburgh, E.; Cleland, R. E.

    1988-01-01

    Treatment of bean (Phaseolus vulgaris L.) seedlings with low levels of salinity (50 or 100 millimolar NaCl) decreased the rate of light-induced leaf cell expansion in the primary leaves over a 3 day period. This decrease could be due to a reduction in one or both of the primary cellular growth parameters: wall extensibility and cell turgor. Wall extensibility was assessed by the Instron technique. Salinity did not decrease extensibility and caused small increases relative to the controls after 72 hours. On the other hand, 50 millimolar NaCl caused a significant reduction in leaf bulk turgor at 24 hours; adaptive decreases in leaf osmotic potential (osmotic adjustment) were more than compensated by parallel decreases in xylem tension potential and the leaf apoplastic solute potential, resulting in a decreased leaf water potential. It is concluded that in bean seedlings, mild salinity initially affects leaf growth rate by a decrease in turgor rather than by a reduction in wall extensibility. Moreover, long-term salinization (10 days) resulted in an apparent mechanical adjustment, i.e. an increase in wall extensibility, which may help counteract reductions in turgor and maintain leaf growth rates.

  18. Cadillac Desert: Water and the Transformation of Nature. A Discussion and Viewer's Guide to the PBS Series.

    ERIC Educational Resources Information Center

    McDowell, Ceasar L.; Reisner, Marc; Bonk, Laura; Wisehart, Bob

    Cadillac Desert is a four-part Public Broadcasting Service (PBS) video series on the remaking of America's West through startling feats of engineering and the consequences that this manipulation of water and nature has wrought. This guide is meant to serve as a resource for discussing the issues raised in the series. The first part of the guide…

  19. Development of Pinhole-Free Amorphous Aluminum Oxide Protective Layers for Biomedical Device Applications

    PubMed Central

    Litvinov, Julia; Wang, Yi-Ju; George, Jinnie; Chinwangso, Pawilai; Brankovic, Stanko; Willson, Richard C.; Litvinov, Dmitri

    2013-01-01

    This paper describes synthesis of ultrathin pinhole-free insulating aluminum oxide layers for electronic device protection in corrosive liquid environments, such as phosphate buffered saline (PBS) or clinical fluids, to enable emerging biomedical applications such as biomolecular sensors. A pinhole-free 25-nm thick amorphous aluminum oxide layer has been achieved using ultra-high vacuum DC magnetron reactive sputtering of aluminum in oxygen/argon plasma followed by oxygen plasma post-processing. Deposition parameters were optimized to achieve the best corrosion protection of lithographically defined device structures. Electrochemical deposition of copper through the aluminum oxide layers was used to detect the presence (or absence) of pinholes. FTIR, XPS, and spectroscopic ellipsometry were used to characterize the material properties of the protective layers. Electrical resistance of the copper device structures protected by the aluminum oxide layers and exposed to a PBS solution was used as a metric to evaluate the long-term stability of these device structures. PMID:23682201

  20. Novel ZnO/MgO/Fe2O3 composite optomagnetic nanoparticles.

    PubMed

    Kamińska, I; Sikora, B; Fronc, K; Dziawa, P; Sobczak, K; Minikayev, R; Paszkowicz, W; Elbaum, D

    2013-05-15

    A facile sol-gel synthesis of novel ZnO/MgO/Fe2O3 nanoparticles (NPs) is reported and their performance is compared to that of ZnO/MgO. Powder x-ray diffraction (XRD) patterns reveal the crystal structure of the prepared samples. The average particle size of the sample was found to be 4.8 nm. The optical properties were determined by UV-vis absorption and fluorescence measurements. The NPs are stable in biologically relevant solutions (phosphate buffered saline (PBS), 20 mM, pH = 7.0) contrary to ZnO/MgO NPs which degrade in the presence of inorganic phosphate. Superparamagnetic properties were determined with a superconducting quantum interference device (SQUID). Biocompatible and stable in PBS ZnO/MgO/Fe2O3 core/shell composite nanocrystals show luminescent and magnetic properties confined to a single NP at room temperature (19-24 ° C), which may render the material to be potentially useful for biomedical applications.

  1. The transcriptional regulator, CosR, controls compatible solute biosynthesis and transport, motility and biofilm formation in Vibrio cholerae.

    PubMed

    Shikuma, Nicholas J; Davis, Kimberly R; Fong, Jiunn N C; Yildiz, Fitnat H

    2013-05-01

    Vibrio cholerae inhabits aquatic environments and colonizes the human digestive tract to cause the disease cholera. In these environments, V. cholerae copes with fluctuations in salinity and osmolarity by producing and transporting small, organic, highly soluble molecules called compatible solutes, which counteract extracellular osmotic pressure. Currently, it is unclear how V. cholerae regulates the expression of genes important for the biosynthesis or transport of compatible solutes in response to changing salinity or osmolarity conditions. Through a genome-wide transcriptional analysis of the salinity response of V. cholerae, we identified a transcriptional regulator we name CosR for compatible solute regulator. The expression of cosR is regulated by ionic strength and not osmolarity. A transcriptome analysis of a ΔcosR mutant revealed that CosR represses genes involved in ectoine biosynthesis and compatible solute transport in a salinity-dependent manner. When grown in salinities similar to estuarine environments, CosR activates biofilm formation and represses motility independently of its function as an ectoine regulator. This is the first study to characterize a compatible solute regulator in V. cholerae and couples the regulation of osmotic tolerance with biofilm formation and motility. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  2. Mantle wedge infiltrated with saline fluids from dehydration and decarbonation of subducting slab

    PubMed Central

    Kawamoto, Tatsuhiko; Yoshikawa, Masako; Kumagai, Yoshitaka; Mirabueno, Ma. Hannah T.; Okuno, Mitsuru; Kobayashi, Tetsuo

    2013-01-01

    Slab-derived fluids play an important role in heat and material transfer in subduction zones. Dehydration and decarbonation reactions of minerals in the subducting slab have been investigated using phase equilibria and modeling of fluid flow. Nevertheless, direct observations of the fluid chemistry and pressure–temperature conditions of fluids are few. This report describes CO2-bearing saline fluid inclusions in spinel-harzburgite xenoliths collected from the 1991 Pinatubo pumice deposits. The fluid inclusions are filled with saline solutions with 5.1 ± 1.0% (wt) NaCl-equivalent magnesite crystals, CO2-bearing vapor bubbles, and a talc and/or chrysotile layer on the walls. The xenoliths contain tremolite amphibole, which is stable in temperatures lower than 830 °C at the uppermost mantle. The Pinatubo volcano is located at the volcanic front of the Luzon arc associated with subduction of warm oceanic plate. The present observation suggests hydration of forearc mantle and the uppermost mantle by slab-derived CO2-bearing saline fluids. Dehydration and decarbonation take place, and seawater-like saline fluids migrate from the subducting slab to the mantle wedge. The presence of saline fluids is important because they can dissolve more metals than pure H2O and affect the chemical evolution of the mantle wedge. PMID:23716664

  3. Mantle wedge infiltrated with saline fluids from dehydration and decarbonation of subducting slab.

    PubMed

    Kawamoto, Tatsuhiko; Yoshikawa, Masako; Kumagai, Yoshitaka; Mirabueno, Ma Hannah T; Okuno, Mitsuru; Kobayashi, Tetsuo

    2013-06-11

    Slab-derived fluids play an important role in heat and material transfer in subduction zones. Dehydration and decarbonation reactions of minerals in the subducting slab have been investigated using phase equilibria and modeling of fluid flow. Nevertheless, direct observations of the fluid chemistry and pressure-temperature conditions of fluids are few. This report describes CO2-bearing saline fluid inclusions in spinel-harzburgite xenoliths collected from the 1991 Pinatubo pumice deposits. The fluid inclusions are filled with saline solutions with 5.1 ± 1.0% (wt) NaCl-equivalent magnesite crystals, CO2-bearing vapor bubbles, and a talc and/or chrysotile layer on the walls. The xenoliths contain tremolite amphibole, which is stable in temperatures lower than 830 °C at the uppermost mantle. The Pinatubo volcano is located at the volcanic front of the Luzon arc associated with subduction of warm oceanic plate. The present observation suggests hydration of forearc mantle and the uppermost mantle by slab-derived CO2-bearing saline fluids. Dehydration and decarbonation take place, and seawater-like saline fluids migrate from the subducting slab to the mantle wedge. The presence of saline fluids is important because they can dissolve more metals than pure H2O and affect the chemical evolution of the mantle wedge.

  4. The low salinity effect at high temperatures

    DOE PAGES

    Xie, Quan; Brady, Patrick V.; Pooryousefy, Ehsan; ...

    2017-04-05

    The mechanism(s) of low salinity water flooding (LSWF) must be better understood at high temperatures and pressures if the method is to be applied in high T/P kaolinite-bearing sandstone reservoirs. We measured contact angles between a sandstone and an oil (acid number, AN = 3.98 mg KOH/g, base number, BN = 1.3 mg KOH/g) from a reservoir in the Tarim Field in western China in the presence of various water chemistries. We examined the effect of aqueous ionic solutions (formation brine, 100X diluted formation brine, and softened water), temperature (60, 100 and 140 °C) and pressure (20, 30, 40, andmore » 50 MPa) on the contact angle. We also measured the zeta potential of the oil/water and water/rock interfaces to calculate oil/brine/rock disjoining pressures. A surface complexation model was developed to interpret contact angle measurements and compared with DLVO theory predictions. Contact angles were greatest in formation water, followed by the softened water, and low salinity water at the same pressure and temperature. Contact angles increased slightly with temperature, whereas pressure had little effect. DLVO and surface complexation modelling predicted similar wettability trends and allow reasonably accurate interpretation of core-flood results. Water chemistry has a much larger impact on LSWF than reservoir temperature and pressure. As a result, low salinity water flooding should work in high temperature and high pressure kaolinite-bearing sandstone reservoirs.« less

  5. The low salinity effect at high temperatures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xie, Quan; Brady, Patrick V.; Pooryousefy, Ehsan

    The mechanism(s) of low salinity water flooding (LSWF) must be better understood at high temperatures and pressures if the method is to be applied in high T/P kaolinite-bearing sandstone reservoirs. We measured contact angles between a sandstone and an oil (acid number, AN = 3.98 mg KOH/g, base number, BN = 1.3 mg KOH/g) from a reservoir in the Tarim Field in western China in the presence of various water chemistries. We examined the effect of aqueous ionic solutions (formation brine, 100X diluted formation brine, and softened water), temperature (60, 100 and 140 °C) and pressure (20, 30, 40, andmore » 50 MPa) on the contact angle. We also measured the zeta potential of the oil/water and water/rock interfaces to calculate oil/brine/rock disjoining pressures. A surface complexation model was developed to interpret contact angle measurements and compared with DLVO theory predictions. Contact angles were greatest in formation water, followed by the softened water, and low salinity water at the same pressure and temperature. Contact angles increased slightly with temperature, whereas pressure had little effect. DLVO and surface complexation modelling predicted similar wettability trends and allow reasonably accurate interpretation of core-flood results. Water chemistry has a much larger impact on LSWF than reservoir temperature and pressure. As a result, low salinity water flooding should work in high temperature and high pressure kaolinite-bearing sandstone reservoirs.« less

  6. Remote sensing of salinity

    NASA Technical Reports Server (NTRS)

    Thomann, G. C.

    1975-01-01

    The complex dielectric constant of sea water is a function of salinity at 21 cm wavelength, and sea water salinity can be determined by a measurement of emissivity at 21 cm along with a measurement of thermodynamic temperature. Three aircraft and one helicopter experiments using two different 21 cm radiometers were conducted under different salinity and temperature conditions. Single or multiple ground truth measurements were used to calibrate the data in each experiment. It is inferred from these experiments that accuracies of 1 to 2%/OO are possible with a single surface calibration point necessary only every two hours if the following conditions are met--water temperatures above 20 C, salinities above 10%/OO, and level plane flight. More frequent calibration, constraint of the aircraft's orientation to the same as it was during calibration, and two point calibration (at a high and low salinity level) rather than single point calibration may give even better accuracies in some instances.

  7. Acclimation of CO2 Assimilation in Cotton Leaves to Water Stress and Salinity 1

    PubMed Central

    Plaut, Zvi; Federman, Evelyn

    1991-01-01

    Cotton (Gossypium hirsutum L. cv Acala SJ2) plants were exposed to three levels of osmotic or matric potentials. The first was obtained by salt and the latter by withholding irrigation water. Plants were acclimated to the two stress types by reducing the rate of stress development by a factor of 4 to 7. CO2 assimilation was then determined on acclimated and nonacclimated plants. The decrease of CO2 assimilation in salinity-exposed plants was significantly less in acclimated as compared with nonacclimated plants. Such a difference was not found under water stress at ambient CO2 partial pressure. The slopes of net CO2 assimilation versus intercellular CO2 partial pressure, for the initial linear portion of this relationship, were increased in plants acclimated to salinity of −0.3 and −0.6 megapascal but not in nonacclimated plants. In plants acclimated to water stress, this change in slopes was not significant. Leaf osmotic potential was reduced much more in acclimated than in nonacclimated plants, resulting in turgor maintenance even at −0.9 megapascal. In nonacclimated plants, turgor pressure reached zero at approximately −0.5 megapascal. The accumulation of Cl− and Na+ in the salinity-acclimated plants fully accounted for the decrease in leaf osmotic potential. The rise in concentration of organic solutes comprised only 5% of the total increase in solutes in salinity-acclimated and 10 to 20% in water-stress-acclimated plants. This acclimation was interpreted in light of the higher protein content per unit leaf area and the enhanced ribulose bisphosphate carboxylase activity. At saturating CO2 partial pressure, the declined inhibition in CO2 assimilation of stress-acclimated plants was found for both salinity and water stress. ImagesFigure 2 PMID:16668429

  8. The occurrence and behavior of radium in saline formation water of the U.S. Gulf Coast region

    USGS Publications Warehouse

    Kraemer, T.F.; Reid, D.F.

    1984-01-01

    Radium has been measured in deep saline formation waters produced from a variety of U.S. Gulf Coast subsurface environments, including oil reservoirs, gas reservoirs and water-producing geopressured aquifers. A strong positive correlation has been found between formation-water salinity and Ra activity, resulting from the interaction of formation water with aquifer matrix. Ra isotopes enter the fluid phase after being produced by the decay of parent elements U and Th, which are located at sites on and within the solid matrix. Processes that are belived to be primarily responsible for transferring Ra from matrix to formation water are chemical leaching and alpha-particle recoil. Factors controlling the observed salinity-Ra relationship may be one or a combination of the following factors: (a) ion exchange; (b) increased solubility of matrix silica surrounding Ra atoms, coupled with a salinity-controlled rate of reequilibration of silica between solution and quartz grains; and (c) the equilibration of Ra in solution with detrial barite within the aquifer. No difference was found in the brine-Ra relation in water produced from oil or gas wells and water produced from wells penetrating only water-bearing aquifers, although the relation was more highly correlated for water-bearing aquifers than hydrocarbon-containing reservoirs. ?? 1984.

  9. Cullin 5 Expression in the Rat: Cellular and Tissue Distribution, and Changes in Response to Water Deprivation and Hemorrhagic Shock

    DTIC Science & Technology

    2003-02-28

    of Health p53 tumor suppressor PBS phosphate buffered saline PCO2 partial pressure of carbon dioxide PO2 partial pressure of oxygen PCR...buffered saline TTBS tween-20 tris buffered saline TonEBP tonicity-response enhancer binding protein TSNRP TriService Nursing Research Program...growth and metabolism (Hochstrasser, 1995; Deshaies, 1999). Although traditionally seen as no more than a means of eliminating no longer needed

  10. Covalent conjugation of graphene oxide with methotrexate and its antitumor activity

    NASA Astrophysics Data System (ADS)

    Wojtoniszak, M.; Urbas, K.; Perużyńska, M.; Kurzawski, M.; Droździk, M.; Mijowska, E.

    2013-05-01

    Here, we have functionalized graphene oxide with anticancer drug methotrexate through amide bonding. A kinetics of the drug release from graphene oxide in physiological solution - phosphate buffered saline (PBS) containing different biocompatible polymers have been investigated. Dispersion of MTX-GO in poly sodium-4-styrene sulfonate and poly ethylene glycol resulted in increase of the release time. The material was characterized with transmission electron microscopy, atomic force microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy and UV-vis spectroscopy. Furthermore, antineoplastic action against human breast adenocarcinoma cell line MCF7 of MTX-GO and empty graphene oxide was explored.

  11. The Effect of Light Intensity, Temperature, and Oxygen Pressure on the Photo-Oxidation Rate of Bare PbS Quantum Dots.

    PubMed

    Liu, Huiyan; Dong, Qian; Lopez, Rene

    2018-05-18

    The oxidation speed of PbS quantum dots has been a subject of controversy for some time. In this study, we reveal the precise functional form of the oxidation rate constant for bare quantum dots through analysis of their photoluminescence as a function of temperature, oxygen pressure, and excitation-laser intensity. The combined effect of these factors results in a reduced energy barrier that allows the oxidation to proceed at a high rate. Each absorbed photon is found to have a 10 -8 probability of oxidizing a PbS atomic pair. This highlights the importance of photo-excitation on the speed of the oxidation process, even at low illumination conditions. The procedure used here may set up a quantitative standard useful for characterizing the stability of quantum dots coated with ligands/linkers, and to compare different protection schemes in a fair quantitative way.

  12. Polyelectrolyte-coated carbons used in the generation of blue energy from salinity differences.

    PubMed

    Ahualli, S; Jiménez, M L; Fernández, M M; Iglesias, G; Brogioli, D; Delgado, A V

    2014-12-14

    In this work we present a method for the production of clean, renewable electrical energy from the exchange of solutions with different salinities. Activated carbon films are coated with negatively or positively charged polyelectrolytes using well-established adsorption methods. When two oppositely charged coated films are placed in contact with an ionic solution, the potential difference between them will be equal to the difference between their Donnan potentials, and hence, energy can be extracted by building an electrochemical cell with such electrodes. A model is elaborated on the operation of the cell, based on the electrokinetic theory of soft particles. All the features of the model are experimentally reproduced, although a small quantitative difference concerning the maximum open-circuit voltage is found, suggesting that the coating is the key point to improve the efficiency. In the experimental conditions used, we obtain a power of 12.1 mW m(-2). Overall, the method proves to be a fruitful and simple approach to salinity-gradient energy production.

  13. Preparation of PbS Nanoparticles by Phase-Transfer Method and Application to Pb2+-Selective Electrode Based on PVC Membrane

    PubMed Central

    Song, Weihong; Wu, Chunhui; Yin, Hongzong; Liu, Xiaoyan; Sa, Panpan; Hu, Jinyang

    2008-01-01

    A novel approach to prepare homogeneous PbS nanoparticles by phase-transfer method was developed. The preparatory conditions were studied in detail, and the nanoparticles were characterized by transmission electron microscopy (TEM) and UV-vis spectroscopy. Then a novel lead ion-selective electrode of polyvinyl chloride (PVC) membrane based on these lead sulfide nanoparticles was prepared, and the optimum ratio of components in the membrane was determined. The results indicated that the sensor exhibited a wide concentration range of 1.0×10−5 to 1.0×10−2 mol.L−1. The response time of the electrode was about 10 s, and the optimal pH in which the electrode could be used was from 3.0 to 7.0. Selectivity coefficients indicated that the electrode was selective to the primary ion over the interfering ion. The electrode can be used for at least 3 months without any divergence in potential. It was successfully applied to directly determine lead ions in solution and used as an indicator electrode in potentiometric titration of lead ions with EDTA. PMID:19112518

  14. Assessment on Experimental Bacterial Biofilms and in Clinical Practice of the Efficacy of Sampling Solutions for Microbiological Testing of Endoscopes

    PubMed Central

    Aumeran, C.; Thibert, E.; Chapelle, F. A.; Hennequin, C.; Lesens, O.

    2012-01-01

    Opinions differ on the value of microbiological testing of endoscopes, which varies according to the technique used. We compared the efficacy on bacterial biofilms of sampling solutions used for the surveillance of the contamination of endoscope channels. To compare efficacy, we used an experimental model of a 48-h Pseudomonas biofilm grown on endoscope internal tubing. Sampling of this experimental biofilm was performed with a Tween 80-lecithin-based solution, saline, and sterile water. We also performed a randomized prospective study during routine clinical practice in our hospital sampling randomly with two different solutions the endoscopes after reprocessing. Biofilm recovery expressed as a logarithmic ratio of bacteria recovered on bacteria initially present in biofilm was significantly more effective with the Tween 80-lecithin-based solution than with saline solution (P = 0.002) and sterile water (P = 0.002). There was no significant difference between saline and sterile water. In the randomized clinical study, the rates of endoscopes that were contaminated with the Tween 80-lecithin-based sampling solution and the saline were 8/25 and 1/25, respectively (P = 0.02), and the mean numbers of bacteria recovered were 281 and 19 CFU/100 ml (P = 0.001), respectively. In conclusion, the efficiency and therefore the value of the monitoring of endoscope reprocessing by microbiological cultures is dependent on the sampling solutions used. A sampling solution with a tensioactive action is more efficient than saline in detecting biofilm contamination of endoscopes. PMID:22170930

  15. Electronic structure calculations of PbS quantum rods and tubes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pimachev, Artem; Dahnovsky, Yuri, E-mail: yurid@uwyo.edu

    2014-01-28

    We study absorption spectra, optical and HOMO-LUMO gaps, and the density of states for PbS quantum rods (QRs) and tubes (QTs). We find some similarities and also differences in QR and QT properties. For both QRs and QTs, the optical and HOMO-LUMO gaps reach the plateaus for small lengths. We find that tubes are as stable as rods. The optical spectra exhibit a peak that can be due to the electron-hole interaction or be a prototype of an S{sub e}–S{sub h} transition in the effective mass approximation. We also calculate the density of states by the density functional theory (DFT)more » and time-dependent density functional theory (TDDFT) methods. The TDDFT density of states function is shifted towards the red side by 0.5 eV indicating the strong e-h interaction.« less

  16. Optical Absorbance Enhancement in PbS QD/Cinnamate Ligand Complexes.

    PubMed

    Kroupa, Daniel M; Vörös, Márton; Brawand, Nicholas P; Bronstein, Noah; McNichols, Brett W; Castaneda, Chloe V; Nozik, Arthur J; Sellinger, Alan; Galli, Giulia; Beard, Matthew C

    2018-06-08

    We studied the optical absorption enhancement in colloidal suspensions of PbS quantum dots (QD) upon ligand exchange from oleate to a series of cinnamate ligands. By combining experiments and ab initio simulations, we elucidate physical parameters that govern the optical absorption enhancement. We find that, within the cinnamate/PbS QD system, the optical absorption enhancement scales linearly with the electronic gap of the ligand, indicating that the ligand/QD coupling occurs equally efficient between the QD and ligand HOMO and their respective LUMO levels. Disruption of the conjugation that connects the aromatic ring and its substituents to the QD core causes a reduction of the electronic coupling. Our results further support the notion that the ligand/QD complex should be considered as a distinct chemical system with emergent behavior rather than a QD core with ligands whose sole purpose is to passivate surface dangling bonds and prevent agglomeration.

  17. Salinity of the Delaware Estuary

    USGS Publications Warehouse

    Cohen, Bernard; McCarthy, Leo T.

    1962-01-01

    The purpose of this investigation was to obtain data on and study the factors affecting the salinity of the Delaware River from Philadelphia, Pa., to the Appoquinimink River, Del. The general chemical quality of water in the estuary is described, including changes in salinity in the river cross section and profile, diurnal and seasonal changes, and the effects of rainfall, sea level, and winds on salinity. Relationships are established of the concentrations of chloride and dissolved solids to specific conductance. In addition to chloride profiles and isochlor plots, time series are plotted for salinity or some quantity representing salinity, fresh-water discharge, mean river level, and mean sea level. The two major variables which appear to have the greatest effect on the salinity of the estuary are the fresh-water flow of the river and sea level. The most favorable combination of these variables for salt-water encroachment occurs from August to early October and the least favorable combination occurs between December and May.

  18. Salinity Trends in the Upper Colorado River Basin Upstream From the Grand Valley Salinity Control Unit, Colorado, 1986-2003

    USGS Publications Warehouse

    Leib, Kenneth J.; Bauch, Nancy J.

    2008-01-01

    In 1974, the Colorado River Basin Salinity Control Act was passed into law. This law was enacted to address concerns regarding the salinity content of the Colorado River. The law authorized various construction projects in selected areas or 'units' of the Colorado River Basin intended to reduce the salinity load in the Colorado River. One such area was the Grand Valley Salinity Control Unit in western Colorado. The U. S. Geological Survey has done extensive studies and research in the Grand Valley Salinity Control Unit that provide information to aid the U.S. Bureau of Reclamation and the Natural Resources Conservation Service in determining where salinity-control work may provide the best results, and to what extent salinity-control work was effective in reducing salinity concentrations and loads in the Colorado River. Previous studies have indicated that salinity concentrations and loads have been decreasing downstream from the Grand Valley Salinity Control Unit, and that the decreases are likely the result of salinity control work in these areas. Several of these reports; however, also document decreasing salinity loads upstream from the Grand Valley Salinity Control Unit. This finding was important because only a small amount of salinity-control work was being done in areas upstream from the Grand Valley Salinity Control Unit at the time the findings were reported (late 1990?s). As a result of those previous findings, the U.S. Bureau of Reclamation entered into a cooperative agreement with the U.S. Geological Survey to investigate salinity trends in selected areas bracketing the Grand Valley Salinity Control Unit and regions upstream from the Grand Valley Salinity Control Unit. The results of the study indicate that salinity loads were decreasing upstream from the Grand Valley Salinity Control Unit from 1986 through 2003, but the rates of decrease have slowed during the last 10 years. The average rate of decrease in salinity load upstream from the Grand Valley

  19. Measuring Salinity by Conductivity.

    ERIC Educational Resources Information Center

    Lapworth, C. J.

    1981-01-01

    Outlines procedures for constructing an instrument which uses an electrode and calibration methods to measure the salinity of waters in environments close to and affected by a saline estuary. (Author/DC)

  20. A broadband helical saline water liquid antenna for wearable systems

    NASA Astrophysics Data System (ADS)

    Li, Gaosheng; Huang, Yi; Gao, Gui; Yang, Cheng; Lu, Zhonghao; Liu, Wei

    2018-04-01

    A broadband helical liquid antenna made of saline water is proposed. A transparent hollow support is employed to fabricate the antenna. The rotation structure is fabricated with a thin flexible tube. The saline water with a concentration of 3.5% can be injected into or be extracted out from the tube to change the quantity of the solution. Thus, the tunability of the radiation pattern could be realised by applying the fluidity of the liquid. The radiation feature of the liquid antenna is compared with that of a metal one, and fairly good agreement has been achieved. Furthermore, three statements of the radiation performance corresponding to the ratio of the diameter to the wavelength of the helical saline water antenna have been proposed. It has been found that the resonance frequency increases when the length of the feeding probe or the radius of the vertical part of the liquid decreases. The fractional bandwidth can reach over 20% with a total height of 185 mm at 1.80 GHz. The measured results indicate reasonable approximation to the simulated. The characteristics of the liquid antenna make it a good candidate for various wireless applications, especially the wearable systems.

  1. Sub-lethal heat treatment affects the tolerance of Cronobacter sakazakii BCRC 13988 to various organic acids, simulated gastric juice and bile solution.

    PubMed

    Hsiao, Wan-Ling; Ho, Wei-Li; Chou, Cheng-Chun

    2010-12-15

    Cronobacter spp., formerly Enterobacter sakazakii, are considered emerging opportunistic pathogens and the etiological agent of life-threatening bacterial infections in infants. In the present study, C. sakazakii BCRC 13988 was first subjected to sub-lethal heat treatment at 47°C for 15min. Survival rates of the heat-shocked and non-shocked C. sakazakii cells in phosphate buffer solution (PBS, pH 4.0) containing organic acids (e.g. acetic, propionic, citric, lactic or tartaric acid), simulated gastric juice (pH 2.0-4.0), and bile solution (0.5 and 2.0%) were examined. Results revealed that sub-lethal heat treatment enhanced the test organism's tolerance to organic acids, although the extent of increased acid tolerance varied with the organic acid examined. Compared with the control cells, heat-shocked C. sakazakii cells after 120-min of exposure, exhibited the largest increase in tolerance in the lactic acid-containing PBS. Furthermore, although heat shock did not affect the behavior of C. sakazakii in bile solution, it increased the test organism's survival when exposed to simulated gastric juice with a pH of 3.0-4.0. Copyright © 2010. Published by Elsevier B.V.

  2. Fluid resuscitation with lactated Ringer’s solution vs normal saline in acute pancreatitis: A triple-blind, randomized, controlled trial

    PubMed Central

    Herrera-Marante, Iván; González-Camacho, Verónica; Bonjoch, Laia; Quesada-Vázquez, Noé; Almenta-Saavedra, Isabel; Miralles-Maciá, Cayetano; Acevedo-Piedra, Nelly G; Roger-Ibáñez, Manuela; Sánchez-Marin, Claudia; Osuna-Ligero, Rosa; Gracia, Ángel; Llorens, Pere; Zapater, Pedro; Singh, Vikesh K; Moreu-Martín, Rocío; Closa, Daniel

    2017-01-01

    Background Little is known regarding the optimal type of fluid resuscitation in acute pancreatitis (AP). Objective The objective of this article was to compare the effect of lactated Ringer’s solution (LR) vs normal saline (NS) in the inflammatory response in AP. Methods We conducted a triple-blind, randomized, controlled trial. Patients ≥ 18 admitted with AP were eligible. Patients were randomized to receive LR or NS. Primary outcome variables were number of systemic inflammatory response syndrome (SIRS) criteria at 24 hours, 48 hours and 72 hours and blood C-reactive protein (CRP) levels at 48 hours and 72 hours. In vitro complementary experiments were performed to further explore the interaction between pH, lactate and inflammation. Results Nineteen patients receiving LR and 21 receiving NS were analyzed. The median (p25–p75) number of SIRS criteria at 48 hours were 1 (1–2) for NS vs 1 (0–1) for LR, p = 0.060. CRP levels (mg/l) were as follows: at 48 hours NS 166 (78–281) vs LR 28 (3–124), p = 0.037; at 72 hours NS 217 (59–323) vs LR 25 (3–169), p = 0.043. In vitro, LR inhibited the induction of inflammatory phenotype of macrophages and NF-κB activation. This effect was not observed when using Ringer’s solution without lactate, suggesting a direct anti-inflammatory effect of lactate. Conclusions Lactated Ringer’s is associated with an anti-inflammatory effect in patients with acute pancreatitis. PMID:29435315

  3. Analysis of the Dielectric constant of saline-alkali soils and the effect on radar backscattering coefficient: a case study of soda alkaline saline soils in Western Jilin Province using RADARSAT-2 data.

    PubMed

    Li, Yang-yang; Zhao, Kai; Ren, Jian-hua; Ding, Yan-ling; Wu, Li-li

    2014-01-01

    Soil salinity is a global problem, especially in developing countries, which affects the environment and productivity of agriculture areas. Salt has a significant effect on the complex dielectric constant of wet soil. However, there is no suitable model to describe the variation in the backscattering coefficient due to changes in soil salinity content. The purpose of this paper is to use backscattering models to understand behaviors of the backscattering coefficient in saline soils based on the analysis of its dielectric constant. The effects of moisture and salinity on the dielectric constant by combined Dobson mixing model and seawater dielectric constant model are analyzed, and the backscattering coefficient is then simulated using the AIEM. Simultaneously, laboratory measurements were performed on ground samples. The frequency effect of the laboratory results was not the same as the simulated results. The frequency dependence of the ionic conductivity of an electrolyte solution is influenced by the ion's components. Finally, the simulated backscattering coefficients measured from the dielectric constant with the AIEM were analyzed using the extracted backscattering coefficient from the RADARSAT-2 image. The results show that RADARSAT-2 is potentially able to measure soil salinity; however, the mixed pixel problem needs to be more thoroughly considered.

  4. [Investigation and canonical correspondence analysis of salinity contents in secondary salinization greenhouse soils in Shanghai suburb].

    PubMed

    Tang, Dong; Mao, Liang; Zhi, Yue-e; Zhang, Jin-Zhong; Zhou, Pei; Chai, Xiao-Tong

    2014-12-01

    The salinity characteristics of greenhouse soils with cropping obstacles in Shanghai suburb were investigated and analyzed. The salinity contents of the salinization greenhouse soils showed a trend of first increasing and then decreasing with the increasing cropping duration. The salinized soils mainly included slightly salted, mildly salted and salted soils, which accounted for 17.39%, 56.52% and 13.04%, respectively. Among them, the degree of salinity in greenhouse soil planted with asparagus in Chongming County was the highest. Among the salt ions in greenhouse soils, the cations were mainly Ca2+ and Na+, while the anions were mainly NO3- and SO4(2-). The degree of salinity was mainly influenced by fertilization mode, cropping duration, crop type and management level, which led to the great variation in the salinity contents and salt ions. Canonical correspondence analysis found that the contents of Ca2+, Mg2+ and NO3- in greenhouse soils were greatly affected by cropping duration, and the degree of salinity would be enhanced and attenuated with long-term application of single fertilizer and mixed application of chemical fertilizer and organic manure, respectively. The greenhouse soils in Shanghai suburb could be classified as four patterns influenced by the relationship between salinity ions and samples, and the most soils were influenced by Ca2+, Mg2+, NO3- and Cl-, which required to be primarily controlled.

  5. Solution stability of Captisol-stabilized melphalan (Evomela) versus Propylene glycol-based melphalan hydrochloride injection.

    PubMed

    Singh, Ramsharan; Chen, Jin; Miller, Teresa; Bergren, Michael; Mallik, Rangan

    2016-12-14

    The objective of this study was to compare the stability of recently approved Captisol-stabilized propylene glycol-free melphalan injection (Evomela™) against currently marketed propylene glycol-based melphalan injection. The products were compared as reconstituted solutions in vials as well as admixture solutions prepared from normal saline in infusion bags. Evomela and propylene glycol-based melphalan injection were reconstituted in normal saline and organic custom diluent, respectively, according to their package insert instructions. The reconstituted solutions were diluted in normal saline to obtain drug admixture solutions at specific drug concentrations. Stability of the solutions was studied at room temperature by assay of melphalan and determination of melphalan-related impurities. Results show that based on the increase in total impurities in propylene glycol-based melphalan injection at 0.45 mg/mL, Evomela admixture solutions are about 5, 9, 15 and 29 times more stable at concentrations of 0.45, 1.0, 2.0 and 5.0 mg/mL, respectively. Results confirmed that reconstituted Evomela solution can be stored in the vial for up to 1 h at RT or for up to 24 h at refrigerated temperature (2-8 °C) with no significant degradation. After storage in the vial, it remains stable for an additional 3-29 h after preparation of admixture solution in infusion bags at concentrations of 0.25-5.0 mg/mL, respectively. In addition, Evomela solution in saline, at concentration of 5.0 mg/mL melphalan was bacteriostatic through 72 h storage at 2-8 °C. Formulation of melphalan with Captisol technology significantly improved stability compared to melphalan hydrochloride reconstituted with propylene-glycol based diluents.

  6. Mapping Spatial Variability of Soil Salinity in a Coastal Paddy Field Based on Electromagnetic Sensors

    PubMed Central

    Guo, Yan; Huang, Jingyi; Shi, Zhou; Li, Hongyi

    2015-01-01

    In coastal China, there is an urgent need to increase land area for agricultural production and urban development, where there is a rapid growing population. One solution is land reclamation from coastal tidelands, but soil salinization is problematic. As such, it is very important to characterize and map the within-field variability of soil salinity in space and time. Conventional methods are often time-consuming, expensive, labor-intensive, and unpractical. Fortunately, proximal sensing has become an important technology in characterizing within-field spatial variability. In this study, we employed the EM38 to study spatial variability of soil salinity in a coastal paddy field. Significant correlation relationship between ECa and EC1:5 (i.e. r >0.9) allowed us to use EM38 data to characterize the spatial variability of soil salinity. Geostatistical methods were used to determine the horizontal spatio-temporal variability of soil salinity over three consecutive years. The study found that the distribution of salinity was heterogeneous and the leaching of salts was more significant in the edges of the study field. By inverting the EM38 data using a Quasi-3D inversion algorithm, the vertical spatio-temporal variability of soil salinity was determined and the leaching of salts over time was easily identified. The methodology of this study can be used as guidance for researchers interested in understanding soil salinity development as well as land managers aiming for effective soil salinity monitoring and management practices. In order to better characterize the variations in soil salinity to a deeper soil profile, the deeper mode of EM38 (i.e., EM38v) as well as other EMI instruments (e.g. DUALEM-421) can be incorporated to conduct Quasi-3D inversions for deeper soil profiles. PMID:26020969

  7. Mapping spatial variability of soil salinity in a coastal paddy field based on electromagnetic sensors.

    PubMed

    Guo, Yan; Huang, Jingyi; Shi, Zhou; Li, Hongyi

    2015-01-01

    In coastal China, there is an urgent need to increase land area for agricultural production and urban development, where there is a rapid growing population. One solution is land reclamation from coastal tidelands, but soil salinization is problematic. As such, it is very important to characterize and map the within-field variability of soil salinity in space and time. Conventional methods are often time-consuming, expensive, labor-intensive, and unpractical. Fortunately, proximal sensing has become an important technology in characterizing within-field spatial variability. In this study, we employed the EM38 to study spatial variability of soil salinity in a coastal paddy field. Significant correlation relationship between ECa and EC1:5 (i.e. r >0.9) allowed us to use EM38 data to characterize the spatial variability of soil salinity. Geostatistical methods were used to determine the horizontal spatio-temporal variability of soil salinity over three consecutive years. The study found that the distribution of salinity was heterogeneous and the leaching of salts was more significant in the edges of the study field. By inverting the EM38 data using a Quasi-3D inversion algorithm, the vertical spatio-temporal variability of soil salinity was determined and the leaching of salts over time was easily identified. The methodology of this study can be used as guidance for researchers interested in understanding soil salinity development as well as land managers aiming for effective soil salinity monitoring and management practices. In order to better characterize the variations in soil salinity to a deeper soil profile, the deeper mode of EM38 (i.e., EM38v) as well as other EMI instruments (e.g. DUALEM-421) can be incorporated to conduct Quasi-3D inversions for deeper soil profiles.

  8. TU-H-BRC-03: Evaluation of Very High-Energy Electron (VHEE) Beams in Comparison to VMAT and PBS Treatment Plans

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schueler, E; Loo, B; Maxim, P

    2016-06-15

    Purpose: The aim of this study was to evaluate the performance of very high-energy electron (VHEE) beams in comparison to clinically delivered treatment plans generated with volumetric modulated arc therapy (VMAT) and proton pencil beam scanning (PBS) technology. Methods: Three clinical cases were selected (prostate, lung, and pediatric CNS). The VHEE plans were calculated in the Monte Carlo EGSnrc code and pencil beam doses were calculated using the DOSxyznrc MC code for 100 and 200 MeV beams. Treatment plans with VHEE, VMAT, and PBS were optimized in a research version of RayStation using an in house build script in ordermore » to minimize operator bias between the different techniques. Results: For the prostate cancer case, the PBS plan showed lower mean organ at risk (OAR) doses compared to the other modalities. An exception was the femoral heads, due to the lateral beam arrangements. The VMAT plan showed lower mean doses to the rectum and the bladder compared to the 100 MeV VHEE plan. The lung cancer case showed minor differences between the three modalities. However, the PBS plan showed a lower contralateral lung dose. The pediatric CNS case showed a better conformity and lower spinal cord dose for the 100 MeV VHEE plan. For all cases, the 200 MeV VHEE plans were found to be similar to or better than the 100 MeV VHEE plans. Conclusion: The present study showed that VHEE plans are similar or superior to VMAT plans with reduced mean OAR dose and increased target conformity for a variety of clinical cases. With increased VHEE energy, better conformity and even higher reductions in mean OAR doses can be achieved. Funding: DoD, Award#:W81XWH-13-1-0165, Weston Havens Foundation, Bio-X (Stanford University), the Office of the Dean of the Medical School, the Office of the Provost (Stanford University), and the Swedish Childhood Cancer Foundation. BL and PM are founders of TibaRay,Inc. BL and PM have received research grants from Varian and RaySearch Laboratory.« less

  9. Using p-type PbS Quantum Dots to Quench Photocurrent of Fullerene-Au NP@MoS2 Composite Structure for Ultrasensitive Photoelectrochemical Detection of ATP.

    PubMed

    Li, Meng-Jie; Zheng, Ying-Ning; Liang, Wen-Bin; Yuan, Ruo; Chai, Ya-Qin

    2017-12-06

    Ultrasensitive and rapid quantification of the universal energy currency adenosine triphosphate (ATP) is an extremely critical mission in clinical applications. In this work, a "signal-off" photoelectrochemical (PEC) biosensor was designed for ultrasensitive ATP detection based on a fullerene (C 60 )-decorated Au nanoparticle@MoS 2 (C 60 -Au NP@MoS 2 ) composite material as a signal indicator and a p-type PbS quantum dot (QD) as an efficient signal quencher. Modification of wide band gap C 60 with narrow band gap MoS 2 to form an ideal PEC signal indicator was proposed, which could significantly improve photocurrent conversion efficiency, leading to a desirable PEC signal. In the presence of p-type PbS QDs, the PEC signal of n-type C 60 -Au NP@MoS 2 was effectively quenched because p-type PbS QDs could compete with C 60 -Au NP@MoS 2 to consume light energy and electron donor. Besides, the conversion of a limited amount of target ATP into an amplified output PbS QD-labeled short DNA sequence (output S 1 ) was achieved via target-mediated aptazyme cycling amplification strategy, facilitating ultrasensitive ATP detection. The proposed signal-off PEC strategy exhibited a wide linear range from 1.00 × 10 -2 pM to 100 nM with a low detection limit of 3.30 fM. Importantly, this proposed strategy provides a promising platform to detect ATP at ultralow levels and has potential applications, including diagnosis of ATP-related diseases, monitoring of diseases progression and evaluation of prognosis.

  10. Urethral hydrodistension for management of urethral hypoplasia in prune belly syndrome: long-term results.

    PubMed

    Kajbafzadeh, Abdol-Mohammad; Rasouli, Mohammad Reza; Dianat, SeyedSaeid; Nezami, Behtash G; Mahboubi, Amir Hassan; Sina, Alireza

    2010-11-01

    The aim of the study was to evaluate the efficacy and safety of urethral hydrodistension for management of urethral hypoplasia in prune belly syndrome (PBS). During a 10-year period, 7 infants with PBS and urethral hypoplasia presented either with open urachus or surgically created urinary diversion referred to our hospital. Five milliliters of normal saline was pushed via a 22-gauge plastic angiocatheter into the urethra with simultaneous finger pressure on the perineum to occlude the proximal urethra that was repeated with higher volumes of the solution (up to 20 mL). The procedure was continued until a 6F or 8F feeding tube catheter confirmed the urethral patency. Hydrodistension was repeated in 3-month intervals till complete patency was confirmed by imaging. Median age of the infants was 6 (1-8) months. All urethral hydrodistension were successful after 1 to 3 sessions. Follow-up imaging studies showed significant improvement in all patients except one. Natural and surgically created urinary diversions were closed in 6 infants. The hydrodistension create an equal and constant pressure into the urethral wall without any urethral damage. This technique can be considered along with the other available methods for management of urethral hypoplasia in selected cases of PBS. Copyright © 2010 Elsevier Inc. All rights reserved.

  11. Metabolic Fingerprinting to Assess the Impact of Salinity on Carotenoid Content in Developing Tomato Fruits

    PubMed Central

    Van Meulebroek, Lieven; Hanssens, Jochen; Steppe, Kathy; Vanhaecke, Lynn

    2016-01-01

    As the presence of health-promoting substances has become a significant aspect of tomato fruit appreciation, this study investigated nutrient solution salinity as a tool to enhance carotenoid accumulation in cherry tomato fruit (Solanum lycopersicum L. cv. Juanita). Hereby, a key objective was to uncover the underlying mechanisms of carotenoid metabolism, moving away from typical black box research strategies. To this end, a greenhouse experiment with five salinity treatments (ranging from 2.0 to 5.0 decisiemens (dS) m−1) was carried out and a metabolomic fingerprinting approach was applied to obtain valuable insights on the complicated interactions between salinity treatments, environmental conditions, and the plant’s genetic background. Hereby, several hundreds of metabolites were attributed a role in the plant’s salinity response (at the fruit level), whereby the overall impact turned out to be highly depending on the developmental stage. In addition, 46 of these metabolites embraced a dual significance as they were ascribed a prominent role in carotenoid metabolism as well. Based on the specific mediating actions of the retained metabolites, it could be determined that altered salinity had only marginal potential to enhance carotenoid accumulation in the concerned tomato fruit cultivar. This study invigorates the usefulness of metabolomics in modern agriculture, for instance in modeling tomato fruit quality. Moreover, the metabolome changes that were caused by the different salinity levels may enclose valuable information towards other salinity-related plant processes as well. PMID:27240343

  12. Comparison of the effects of a balanced crystalloid-based and a saline-based tetrastarch solution on canine whole blood coagulation and platelet function.

    PubMed

    Reuteler, Annina; Axiak-Flammer, Shannon; Howard, Judith; Adamik, Katja-Nicole

    2017-01-01

    To evaluate the effects of a 6% hydroxyethyl starch (130/0.42) solution in either a buffered, electrolyte-balanced (HES-BAL), or a saline (HES-SAL) carrier solution on canine platelet function and whole blood coagulation. Prospective, randomized study. University teaching hospital. Thirty-seven client-owned dogs undergoing general anesthesia for arthroscopy or imaging studies. Dogs received a 15 mL/kg intravenous bolus of HES-SAL (n = 13), HES-BAL (n = 14), or a modified Ringer's solution (n = 10) over 30-40 minutes. Coagulation was analyzed using a Platelet Function Analyzer-100 (closure time [Ct PFA ]), and whole blood thromboelastometry (ROTEM) with extrinsically (ex-tem and fib-tem) and intrinsically (in-tem) activated assays, which assessed clotting time (CT), clot formation time (CFT), maximal clot firmness (MCF), and lysis index (LI). Coagulation samples were assayed prior to fluid administration (T0), and 5 minutes (T1), and 3 hours (T2) following fluid bolus administration, respectively. Both HES solutions resulted in impaired platelet function as indicated by a significant prolongation of Ct PFA at T1 as compared to T0, but which resolved by T2. An IV bolus of Ringer's solution did not alter platelet function. In both HES groups, whole blood coagulation was significantly impaired at T1 as indicated by a significant increase in in-tem CFT, and a significant decrease in ex-tem, in-tem, and fib-tem MCF compared to T0. Furthermore, a significant increase in ex-tem CFT at T1 compared to T0 was found in the HES-SAL group. With the exception of in-tem MCF after HES-BAL, these effects were not present at T2. No significant differences were found in Ct PFA or any ROTEM variable at any time point between HES-SAL and HES-BAL. Administration of a single bolus of 15 mL/kg 6% HES 130/0.42 results in significant but short-lived impairment of canine platelet function and whole blood coagulation, regardless of carrier solution. © Veterinary Emergency and Critical Care

  13. SU-F-T-185: Study of the Robustness of a Proton Arc Technique Based On PBS Beams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, Z; Zheng, Y

    Purpose: One potential technique to realize proton arc is through using PBS beams from many directions to form overlaid Bragg peak (OBP) spots and placing these OBP spots throughout the target volume to achieve desired dose distribution. In this study, we analyzed the robustness of this proton arc technique. Methods: We used a cylindrical water phantom of 20 cm in radius in our robustness analysis. To study the range uncertainty effect, we changed the density of the phantom by ±3%. To study the setup uncertainty effect, we shifted the phantom by 3 & 5 mm. We also combined the rangemore » and setup uncertainties (3mm/±3%). For each test plan, we performed dose calculation for the nominal and 6 disturbed scenarios. Two test plans were used, one with single OBP spot and the other consisting of 121 OBP spots covering a 10×10cm{sup 2} area. We compared the dose profiles between the nominal and disturbed scenarios to estimate the impact of the uncertainties. Dose calculation was performed with Gate/GEANT based Monte Carlo software in cloud computing environment. Results: For each of the 7 scenarios, we simulated 100k & 10M events for plans consisting of single OBP spot and 121 OBP spots respectively. For single OBP spot, the setup uncertainty had minimum impact on the spot’s dose profile while range uncertainty had significant impact on the dose profile. For plan consisting of 121 OBP spots, similar effect was observed but the extent of disturbance was much less compared to single OBP spot. Conclusion: For PBS arc technique, range uncertainty has significantly more impact than setup uncertainty. Although single OBP spot can be severely disturbed by the range uncertainty, the overall effect is much less when a large number of OBP spots are used. Robustness optimization for PBS arc technique should consider range uncertainty with priority.« less

  14. On the Balancing of the SMOS Ocean Salinity Retrieval Cost Function

    NASA Astrophysics Data System (ADS)

    Sabia, R.; Camps, A.; Portabella, M.; Talone, M.; Ballabrera, J.; Gourrion, J.; Gabarró, C.; Aretxabaleta, A. L.; Font, J.

    2009-04-01

    The Soil Moisture and Ocean Salinity (SMOS) mission will be launched in mid 2009 to provide synoptic sea surface salinity (SSS) measurements with good temporal resolution [1]. To obtain a proper estimation of the SSS fields derived from the multi-angular brightness temperatures (TB) measured by the Microwave Interferometric Radiometer by Aperture Synthesis (MIRAS) sensor, a comprehensive inversion procedure has been defined [2]. Nevertheless, several salinity retrieval issues remain critical, namely: 1) Scene-dependent bias in the simulated TBs, 2) L-band forward geophysical model function definition, 3) Auxiliary data uncertainties, 4) Constraints in the cost function (inversion), especially in salinity term, and 5) Adequate spatio-temporal averaging. These issues will have to be properly addressed in order to meet the proposed accuracy requirement of the mission: a demanding 0.1 psu (practical salinity units) after averaging in a 30-day and 2°x2° spatio-temporal boxes. The salinity retrieval cost function minimizes the difference between the multi-angular measured SMOS TBs (yet simulated, so far) and the modeled TBs, weighted by the corresponding radiometric noise of the measurements. Furthermore, due to the fact that the minimization problem is both non-linear and ill-posed, background reference terms are needed to nudge the solution and ensuring convergence at the same time [3]. Constraining terms in SSS, sea surface temperature (SST) and wind speed are considered with their respective uncertainties. Moreover, whether SSS constraints have to be included or not as part of the retrieval procedure is still a matter of debate. On one hand, neglecting background reference information on SSS might prevent from retrieving salinity with the prescribed accuracy or at least within reasonable error. Conversely, including constraints in SSS, relying for instance on the climatology, may force the retrieved value to be too close to the reference prior values, thus

  15. Simulated effects of irrigation on salinity in the Arkansas River Valley in Colorado

    USGS Publications Warehouse

    Goff, K.; Lewis, M.E.; Person, M.A.; Konikow, Leonard F.

    1998-01-01

    Agricultural irrigation has a substantial impact on water quantity and quality in the lower Arkansas River valley of southeastern Colorado. A two-dimensional flow and solute transport model was used to evaluate the potential effects of changes in irrigation on the quantity and quality of water in the alluvial aquifer and in the Arkansas River along an 17.7 km reach of the fiver. The model was calibrated to aquifer water level and dissolved solids concentration data collected throughout the 24 year study period (197195). Two categories of irrigation management were simulated with the calibrated model: (1) a decrease in ground water withdrawals for irrigation; and (2) cessation of all irrigation from ground water and surface water sources. In the modeled category of decreased irrigation from ground water pumping, there was a resulting 6.9% decrease in the average monthly ground water salinity, a 0.6% decrease in average monthly river salinity, and an 11.1% increase in ground water return flows to the river. In the modeled category of the cessation of all irrigation, average monthly ground water salinity decreased by 25%; average monthly river salinity decreased by 4.4%; and ground water return flows to the river decreased by an average of 64%. In all scenarios, simulated ground water salinity decreased relative to historical conditions for about 12 years before reaching a new dynamic equilibrium condition. Aquifer water levels were not sensitive to any of the modeled scenarios. These potential changes in salinity could result in improved water quality for irrigation purposes downstream from the affected area.

  16. Comparative Evaluation of Three Homogenization Methods for Isolating Middle East Respiratory Syndrome Coronavirus Nucleic Acids From Sputum Samples for Real-Time Reverse Transcription PCR.

    PubMed

    Sung, Heungsup; Yong, Dongeun; Ki, Chang Seok; Kim, Jae Seok; Seong, Moon Woo; Lee, Hyukmin; Kim, Mi Na

    2016-09-01

    Real-time reverse transcription PCR (rRT-PCR) of sputum samples is commonly used to diagnose Middle East respiratory syndrome coronavirus (MERS-CoV) infection. Owing to the difficulty of extracting RNA from sputum containing mucus, sputum homogenization is desirable prior to nucleic acid isolation. We determined optimal homogenization methods for isolating viral nucleic acids from sputum. We evaluated the following three sputum-homogenization methods: proteinase K and DNase I (PK-DNase) treatment, phosphate-buffered saline (PBS) treatment, and N-acetyl-L-cysteine and sodium citrate (NALC) treatment. Sputum samples were spiked with inactivated MERS-CoV culture isolates. RNA was extracted from pretreated, spiked samples using the easyMAG system (bioMérieux, France). Extracted RNAs were then subjected to rRT-PCR for MERS-CoV diagnosis (DiaPlex Q MERS-coronavirus, SolGent, Korea). While analyzing 15 spiked sputum samples prepared in technical duplicate, false-negative results were obtained with five (16.7%) and four samples (13.3%), respectively, by using the PBS and NALC methods. The range of threshold cycle (Ct) values observed when detecting upE in sputum samples was 31.1-35.4 with the PK-DNase method, 34.7-39.0 with the PBS method, and 33.9-38.6 with the NALC method. Compared with the control, which were prepared by adding a one-tenth volume of 1:1,000 diluted viral culture to PBS solution, the ranges of Ct values obtained by the PBS and NALC methods differed significantly from the mean control Ct of 33.2 (both P<0.0001). The PK-DNase method is suitable for homogenizing sputum samples prior to RNA extraction.

  17. A tension insensitive PbS fiber temperature sensor based on Sagnac interferometer

    NASA Astrophysics Data System (ADS)

    Fu, Xing-hu; Zhang, Jiang-peng; Yang, Kai-li; Dong, Yan-hua; Wen, Jian-xiang; Fu, Guang-wei; Bi, Wei-hong

    2017-03-01

    In this paper, a tension insensitive PbS fiber temperature sensor based on Sagnac interferometer is proposed and demonstrated. The sensing mechanism of tension and temperature is analyzed. The relationships between the interference spectrum, temperature and tension are analyzed, respectively. The experimental temperature range is 36—70 °C. The experimental results show that the interference spectrum is red shifted, and its sensitivity is 53.89 pm/°C. In tension experiment, the tension range is 0—1 400 μɛ. The experimental results show that there is no wavelength shift in the interference spectrum. The sensor is immune to tension cross-sensitivity compared with other sensors. It can be used for temperature testing in aerospace, chemistry and pharmacy.

  18. Saline Sinus Rinse Recipe

    MedlinePlus

    ... Menu Search Main navigation Skip to content Conditions & Treatments Allergies Asthma Primary Immunodeficiency Disease Related Conditions Drug Guide ... Expert Search Search AAAAI Breadcrumb navigation Home ▸ Conditions & Treatments ▸ Library ▸ Allergy Library ▸ Saline Sinus Rinse Recipe Share | Saline Sinus ...

  19. Durum wheat seedlings in saline conditions: Salt spray versus root-zone salinity

    NASA Astrophysics Data System (ADS)

    Spanò, Carmelina; Bottega, Stefania

    2016-02-01

    Salinity is an increasingly serious problem with a strong negative impact on plant productivity. Though many studies have been made on salt stress induced by high NaCl concentrations in the root-zone, few data concern the response of plants to saline aerosol, one of the main constraints in coastal areas. In order to study more in depth wheat salinity tolerance and to evaluate damage and antioxidant response induced by various modes of salt application, seedlings of Triticum turgidum ssp. durum, cv. Cappelli were treated for 2 and 7 days with salt in the root-zone (0, 50 and 200 mM NaCl) or with salt spray (400 mM NaCl + 0 or 200 mM NaCl in the root-zone). Seedlings accumulated Na+ in their leaves and therefore part of their ability to tolerate high salinity seems to be due to Na+ leaf tissue tolerance. Durum wheat, confirmed as a partially tolerant plant, shows a higher damage under airborne salinity, when both an increase in TBA-reactive material (indicative of lipid peroxidation) and a decrease in root growth were recorded. A different antioxidant response was activated, depending on the type of salt supply. Salt treatment induced a depletion of the reducing power of both ascorbate and glutathione while the highest contents of proline were detected under salt spray conditions. In the short term catalase and ascorbate peroxidase co-operated with glutathione peroxidase in the scavenging of hydrogen peroxide, in particular in salt spray-treated plants. From our data, the durum wheat cultivar Cappelli seems to be sensitive to airborne salinity.

  20. Impact of Variable-Density Flow on the Value-of-Information from Pressure and Concentration Data for Saline Aquifer Characterization

    NASA Astrophysics Data System (ADS)

    Yoon, S.; Williams, J. R.; Juanes, R.; Kang, P. K.

    2017-12-01

    Managed aquifer recharge (MAR) is becoming an important solution for ensuring sustainable water resources and mitigating saline water intrusion in coastal aquifers. Accurate estimates of hydrogeological parameters in subsurface flow and solute transport models are critical for making predictions and managing aquifer systems. In the presence of a density difference between the injected freshwater and ambient saline groundwater, the pressure field is coupled to the spatial distribution of salinity distribution, and therefore experiences transient changes. The variable-density effects can be quantified by a mixed convection ratio between two characteristic types of convection: free convection due to density contrast, and forced convection due to a hydraulic gradient. We analyze the variable-density effects on the value-of-information of pressure and concentration data for saline aquifer characterization. An ensemble Kalman filter is used to estimate permeability fields by assimilating the data, and the performance of the estimation is analyzed in terms of the accuracy and the uncertainty of estimated permeability fields and the predictability of arrival times of breakthrough curves in a realistic push-pull setting. This study demonstrates that: 1. Injecting fluids with the velocity that balances the two characteristic convections maximizes the value of data for saline aquifer characterization; 2. The variable-density effects on the value of data for the inverse estimation decrease as the permeability heterogeneity increases; 3. The advantage of joint inversion of pressure and concentration data decreases as the coupling effects between flow and transport increase.

  1. A global algorithm for estimating Absolute Salinity

    NASA Astrophysics Data System (ADS)

    McDougall, T. J.; Jackett, D. R.; Millero, F. J.; Pawlowicz, R.; Barker, P. M.

    2012-12-01

    The International Thermodynamic Equation of Seawater - 2010 has defined the thermodynamic properties of seawater in terms of a new salinity variable, Absolute Salinity, which takes into account the spatial variation of the composition of seawater. Absolute Salinity more accurately reflects the effects of the dissolved material in seawater on the thermodynamic properties (particularly density) than does Practical Salinity. When a seawater sample has standard composition (i.e. the ratios of the constituents of sea salt are the same as those of surface water of the North Atlantic), Practical Salinity can be used to accurately evaluate the thermodynamic properties of seawater. When seawater is not of standard composition, Practical Salinity alone is not sufficient and the Absolute Salinity Anomaly needs to be estimated; this anomaly is as large as 0.025 g kg-1 in the northernmost North Pacific. Here we provide an algorithm for estimating Absolute Salinity Anomaly for any location (x, y, p) in the world ocean. To develop this algorithm, we used the Absolute Salinity Anomaly that is found by comparing the density calculated from Practical Salinity to the density measured in the laboratory. These estimates of Absolute Salinity Anomaly however are limited to the number of available observations (namely 811). In order to provide a practical method that can be used at any location in the world ocean, we take advantage of approximate relationships between Absolute Salinity Anomaly and silicate concentrations (which are available globally).

  2. Effect of salinity on tomato (Lycopersicon esculentum Mill.) during seed germination stage.

    PubMed

    Singh, Jogendra; Sastry, E V Divakar; Singh, Vijayata

    2012-01-01

    A study was conducted using ten genetically diverse genotypes along with their 45F1 (generated by diallel mating) under normal and salt stress conditions. Although, tomato (Lycopersicon esculentum Mill.) is moderately sensitive to salinity but more attention to salinity is yet to be required in the production of tomato. In present study, germination rate, speed of germination, dry weight ratio and Na(+)/K(+) ratio in root and shoot, were the parameters assayed on three salinity levels; control, 1.0 % NaCl and 3.0 % NaCl with Hoagland's solution. Increasing salt stress negatively affected growth and development of tomato. When salt concentration increased, germination of tomato seed was reduced and the time needed to complete germination lengthened, root/shoot dry weight ratio was higher and Na(+) content increased but K(+) content decreased. Among the varieties, Sel-7 followed by Arka Vikas and crosses involving them as a parent were found to be the more tolerant genotypes in the present study on the basis of studied parameters.

  3. Comparison of irrigation solutions and devices in a contaminated musculoskeletal wound survival model.

    PubMed

    Owens, Brett D; White, Daniel W; Wenke, Joseph C

    2009-01-01

    There is much to learn about the effectiveness of different methods currently used for the irrigation of open wounds. The purpose of this study was to compare various approaches in a survival animal model. We used an established goat model involving the creation of a reproducible complex musculoskeletal wound followed by inoculation with Pseudomonas aeruginosa (lux) bacteria. This genetically altered luminescent bacterium provides the ability for quantitative analysis with a photon-counting camera system. For Study 1, wound irrigation was performed six hours after the injury and inoculation; the goats were assigned to four treatment groups: normal saline solution, bacitracin solution, castile soap, and benzalkonium chloride. All wounds received sharp débridement and irrigation with use of a pulsatile lavage device (19 psi). Images and photon counts were obtained prior to irrigation, after irrigation, and forty-eight hours after injury and inoculation. For Study 2, we used the same animal model and compared bulb syringe and pulsatile lavage irrigation with saline solution. In Study 1, the irrigation treatment lowered the bacterial counts in all treatment groups. The greatest reduction was seen with castile soap, which lowered the photon count to 13% of the pretreatment level. This was followed by benzalkonium chloride, bacitracin, and saline solution at 18%, 22%, and 29%, respectively. At forty-eight hours, imaging showed a rebound in bacterial counts in every group. The highest rebound was measured in the castile soap group, which rebounded to 120% of the pretreatment level. The benzalkonium chloride group experienced a rebound to 94% of the pretreatment level. These were followed by bacitracin solution (89%) and normal saline solution (68%). In Study 2, both treatment methods were effective in removing 75% of the bacteria initially. At forty-eight hours, the bacterial levels in the pulsed lavage group rebounded to 94% of the original levels (compared with 48% in

  4. Reinforcement of spinal anesthesia by epidural injection of saline: a comparison of hyperbaric and isobaric tetracaine.

    PubMed

    Yamazaki, Y; Mimura, M; Hazama, K; Namiki, A

    2000-04-25

    An epidural injection of saline was reported to extend spinal anesthesia because of a volume effect. The aim of this study was to evaluate the influence of the baricity of spinal local anesthetics upon the extension of spinal anesthesia by epidural injection of saline. Forty patients undergoing elective lower-limb surgery were randomly allocated to four groups of 10 patients each. Group A received no epidural injection after the spinal administration of hyperbaric tetracaine (dissolved in 10% glucose). Group B received an epidural injection of 8 ml of physiological saline 20 min after spinal hyperbaric tetracaine. Group C received no epidural injection after spinal isobaric tetracaine (dissolved in physiological saline). Group D received an epidural injection of 8 ml of saline 20 min after spinal isobaric tetracaine. The level of analgesia was examined by the pinprick method at 5-min intervals. The levels of analgesia 20 min after spinal anesthesia were significantly higher in hyperbaric groups than in isobaric groups [T5 (T2-L2) vs. T7 (T3-12)]. After epidural injection of saline, the levels of analgesia in groups B and D were significantly higher than in groups A and C. The segmental increases after epidural saline injection were 2 (0-3) in group B and 2 (1-7) in group D. Sensation in the sacral area remained 20 min after spinal block in one patient in group D; however, it disappeared after epidural saline injection. In this study, 8 ml of epidural saline extended spinal analgesia. However, there was no difference between the augmenting effect in isobaric and hyperbaric spinal anesthesia. We conclude that the reinforcement of spinal anesthesia by epidural injection of saline is not affected by the baricity of the spinal anesthetic solution used.

  5. Saline-water resources of Texas

    USGS Publications Warehouse

    Winslow, Allen George; Kister, Lester Ray

    1956-01-01

    Most of the aquifers in Texas contain saline water in some parts, and a few are capable of producing large quantities of saline water. Of the early Paleozoic formations, the Hickory sandstone member of the Riley formation of Cambrian age and the Ellenburger group of Ordovician age are potential sources of small to moderate supplies of saline water in parts of central and west-central Texas.

  6. Coastal hazards and groundwater salinization on low coral islands.

    NASA Astrophysics Data System (ADS)

    Terry, James P.; Chui, T. F. May

    2016-04-01

    Remote oceanic communities living on low-lying coral islands (atolls) without surface water rely for their survival on the continuing viability of fragile groundwater resources. These exist in the form of fresh groundwater lenses (FGLs) that develop naturally within the porous coral sand and gravel substrate. Coastal hazards such as inundation by high-energy waves driven by storms and continuing sea-level rise (SLR) are among many possible threats to viable FGL size and quality on atolls. Yet, not much is known about the combined effects of wave washover during powerful storms and SLR on different sizes of coral island, nor conversely how island size influences lens resilience against damage. This study investigates FGL damage by salinization (and resilience) caused by such coastal hazards using a modelling approach. Numerical modelling is carried out to generate steady-state FGL configurations at three chosen island sizes (400, 600 and 800 m widths). Steady-state solutions reveal how FGL dimensions are related in a non-linear manner to coral island size, such that smaller islands develop much more restricted lenses than larger islands. A 40 cm SLR scenario is then imposed. This is followed by transient simulations to examine storm-induced wave washover and subsequent FGL responses to saline damage over a 1 year period. Smaller FGLs display greater potential for disturbance by SLR, while larger and more robust FGLs tend to show more resilience. Further results produce a somewhat counterintuitive finding: in the post-SLR condition, FGL vulnerability to washover salinization may actually be reduced, owing to the thinner layer of unsaturated substrate lying above the water table into which saline water can infiltrate during a storm event. Nonetheless, combined washover and SLR impacts imply overall that advancing groundwater salinization may lead to some coral islands becoming uninhabitable long before they are completely submerged by sea-level rise, thereby calling

  7. Effect of weakly ionized plasma on osmotic pressure on cell membranes in a saline

    NASA Astrophysics Data System (ADS)

    Shneider, M. N.; Pekker, M.

    2018-05-01

    In this paper, attention is drawn to the importance of accounting for osmotic pressure when analyzing physiological effects on cellular structures in plasma medicine. Interaction of a weakly ionized plasma jet with a saline solution leads to detectable changes in the saline's ion-molecular composition and hence changes in the osmotic pressure. This, in turn, leads to a stretching or compression of the membrane, depending on the difference of total external and internal pressures. The selective effect of plasma on cells, observed in experiments, is associated with the change in the mechanical properties of membranes (and thereby, a weakening of their protective properties). Corresponding estimates are given in the article.

  8. Transmission of Microsporidian Parasites of Mosquitoes.

    DTIC Science & Technology

    1982-01-01

    finely drawn capillary tube calibrated to approximately 1 il. Cholesterol and 20-hydroxyecdysone were dissolved in insect saline with 10% ethanol... saline . Sharpened jeweler’s forceps were then used to remove the ovaries through single ventral incisions between the 6th and 7th abdominal sternites... saline (PBS) in a tissue grinder and then subjected to 2 cycles of differential centrifugation. The spores are then layered onto 0-10% Ludox IIS-40

  9. Transcriptome analysis of salinity responsiveness in contrasting genotypes of finger millet (Eleusine coracana L.) through RNA-sequencing.

    PubMed

    Rahman, Hifzur; Jagadeeshselvam, N; Valarmathi, R; Sachin, B; Sasikala, R; Senthil, N; Sudhakar, D; Robin, S; Muthurajan, Raveendran

    2014-07-01

    Finger millet (Eleusine coracana L.) is a hardy cereal known for its superior level of tolerance against drought, salinity, diseases and its nutritional properties. In this study, attempts were made to unravel the physiological and molecular basis of salinity tolerance in two contrasting finger millet genotypes viz., CO 12 and Trichy 1. Physiological studies revealed that the tolerant genotype Trichy 1 had lower Na(+) to K(+) ratio in leaves and shoots, higher growth rate (osmotic tolerance) and ability to accumulate higher amount of total soluble sugar in leaves under salinity stress. We sequenced the salinity responsive leaf transcriptome of contrasting finger millet genotypes using IonProton platform and generated 27.91 million reads. Mapping and annotation of finger millet transcripts against rice gene models led to the identification of salinity responsive genes and genotype specific responses. Several functional groups of genes like transporters, transcription factors, genes involved in cell signaling, osmotic homeostasis and biosynthesis of compatible solutes were found to be highly up-regulated in the tolerant Trichy 1. Salinity stress inhibited photosynthetic capacity and photosynthesis related genes in the susceptible genotype CO 12. Several genes involved in cell growth and differentiation were found to be up-regulated in both the genotypes but more specifically in tolerant genotype. Genes involved in flavonoid biosynthesis were found to be down-regulated specifically in the salinity tolerant Trichy 1. This study provides a genome-wide transcriptional analysis of two finger millet genotypes differing in their level of salinity tolerance during a gradually progressing salinity stress under greenhouse conditions.

  10. Zwitterionic Antifouling Coatings for the Purification of High-Salinity Shale Gas Produced Water.

    PubMed

    Yang, Rong; Goktekin, Esma; Gleason, Karen K

    2015-11-03

    Fouling refers to the undesirable attachment of organic molecules and microorganisms to submerged surfaces. It is an obstacle to the purification of shale gas produced water and is currently without an effective solution due to the highly contaminated nature of produced water. Here, we demonstrate the direct vapor application of a robust zwitterionic coating to a variety of substrates. The coating remains unprecedentedly hydrophilic, smooth, and effectively antifouling in extremely high salinity solutions (with salt concentration of 200,000 ppm). The fouling resistance is assessed rapidly and quantitatively with a molecular force spectroscopy-based method and corroborated using quartz crystal microbalance system with dissipation monitoring. Grazing angle attenuated total reflectance Fourier transform infrared is used in combination with X-ray photoelectron spectroscopy, atomic force microscope, and in situ spectroscopic ellipsometry to lend insight into the underlying mechanism for the exceptional stability and effectiveness of the zwitterionic coating under high-salinity conditions. A unique coating architecture, where the surface is concentrated with mobile zwitterionic moieties while the bulk is cross-linked to enhance coating durability, was discovered to be the origin of its stable fouling resistance under high salinity. Combined with previously reported exceptional stability in highly oxidative environments and strong fouling resistance to oil and grease, the zwitterionic surface here has the potential to enable low-cost, membrane-based techniques for the purification of produced water and to eventually balance the favorable economics and the concerning environmental impacts of the hydraulic fracturing industry.

  11. Silicon decreases chloride transport in rice (Oryza sativa L.) in saline conditions.

    PubMed

    Shi, Yu; Wang, Yichao; Flowers, Timothy J; Gong, Haijun

    2013-06-15

    Silicon can alleviate salt damage to plants, although the mechanism(s) still remains to be elucidated. In this paper, we report the effect of silicon on chloride transport in rice (Oryza sativa L.) seedlings in saline conditions. In the absence of salinity, silicon enhanced the growth of shoots, but not roots in three cultivars (cv. GR4, IR36, and CSR10). Salinity reduced the growth of both shoots and roots in all three genotypes. In saline conditions, addition of silicon to the culture solution again improved the growth of shoots, but not of roots. Under these saline conditions, the concentrations of chloride in the shoot were markedly decreased by adding silicon and the ratio of K(+)/Cl(-) was significantly increased, while the concentration of chloride in the roots was unchanged. The decrease in chloride concentration in the shoot was correlated with the decrease in transpirational bypass flow in rice, as shown by the transport of the apoplastic tracer trisodium-8-hydroxy-1,3,6-pyrenetrisulphonic acid (PTS). Addition of silicon increased the net photosynthetic rate, stomata conductance, and transpiration of salt-stressed plants in cv. IR36, indicating that the reduction of chloride (and sodium) uptake by silicon was not through a reduction in transpiration rate. Silicon addition also increased the instantaneous water use efficiency of salt-stressed plants, while it did not change the relative growth rate of shoots. The results suggest that silicon addition decreased transpirational bypass flow in the roots, and therefore decreased the transport of chloride to the shoot. Copyright © 2013 Elsevier GmbH. All rights reserved.

  12. Confocal raman microscopy as a non-invasive tool to investigate the phase composition of frozen complex cryopreservation media.

    PubMed

    Kreiner-Møller, A; Stracke, F; Zimmermann, H

    2013-01-01

    Various cryoprotective agents (CPA) are added to cell media in order to avoid cell injury during cryo preservation. The resulting complex environment of the preserved cell, consisting of crystalline and liquid phases can however not be investigated non-invasively by established methods in cryobiology. This study shows how scanning confocal Raman microscopy can non-invasively extract information on chemical composition, phase domain and distribution at cryogenic temperatures. The formation of the salt hydrate, hydrohalite NaCl∙H2O, in solutions comprised of phosphate buffered saline (PBS) and dimethyl sulphoxide (DMSO) is studied in particular. Scanning confocal Raman microscopy can be used to unambiguously identify hydrohalite in a medium containing DMSO and saline. The confocal Raman microscopy imaging along with differential scanning calorimetric measurements further show that the hydrohalite is formed without eutectic formation. This method also allows for discrimination between closely packed hydrohalite crystals that are oriented differently.

  13. The Arabidopsis thaliana HAK5 K+ transporter is required for plant growth and K+ acquisition from low K+ solutions under saline conditions.

    PubMed

    Nieves-Cordones, Manuel; Alemán, Fernando; Martínez, Vicente; Rubio, Francisco

    2010-03-01

    K(+) uptake in the high-affinity range of concentrations and its components have been widely studied. In Arabidposis thaliana, the AtHAK5 transporter and the AtAKT1 channel have been shown to be the main transport proteins involved in this process. Here, we study the role of these two systems under two important stress conditions: low K(+) supply or the presence of salinity. T-DNA insertion lines disrupting AtHAK5 and AtAKT1 are employed for long-term experiments that allow physiological characterization of the mutant lines. We found that AtHAK5 is required for K(+) absorption necessary to sustain plant growth at low K(+) in the absence as well as in the presence of salinity. Salinity greatly reduced AtHAK5 transcript levels and promoted AtAKT1-mediated K(+) efflux, resulting in an important impairment of K(+) nutrition. Although having a limited capacity, AtHAK5 plays a major role for K(+) acquisition from low K(+) concentrations in the presence of salinity.

  14. Improving 4D plan quality for PBS-based liver tumour treatments by combining online image guided beam gating with rescanning

    NASA Astrophysics Data System (ADS)

    Zhang, Ye; Knopf, Antje-Christin; Weber, Damien Charles; Lomax, Antony John

    2015-10-01

    Pencil beam scanned (PBS) proton therapy has many advantages over conventional radiotherapy, but its effectiveness for treating mobile tumours remains questionable. Gating dose delivery to the breathing pattern is a well-developed method in conventional radiotherapy for mitigating tumour-motion, but its clinical efficiency for PBS proton therapy is not yet well documented. In this study, the dosimetric benefits and the treatment efficiency of beam gating for PBS proton therapy has been comprehensively evaluated. A series of dedicated 4D dose calculations (4DDC) have been performed on 9 different 4DCT(MRI) liver data sets, which give realistic 4DCT extracting motion information from 4DMRI. The value of 4DCT(MRI) is its capability of providing not only patient geometries and deformable breathing characteristics, but also includes variations in the breathing patterns between breathing cycles. In order to monitor target motion and derive a gating signal, we simulate time-resolved beams’ eye view (BEV) x-ray images as an online motion surrogate. 4DDCs have been performed using three amplitude-based gating window sizes (10/5/3 mm) with motion surrogates derived from either pre-implanted fiducial markers or the diaphragm. In addition, gating has also been simulated in combination with up to 19 times rescanning using either volumetric or layered approaches. The quality of the resulting 4DDC plans has been quantified in terms of the plan homogeneity index (HI), total treatment time and duty cycle. Results show that neither beam gating nor rescanning alone can fully retrieve the plan homogeneity of the static reference plan. Especially for variable breathing patterns, reductions of the effective duty cycle to as low as 10% have been observed with the smallest gating rescanning window (3 mm), implying that gating on its own for such cases would result in much longer treatment times. In addition, when rescanning is applied on its own, large differences between volumetric

  15. Estuarine Salinity Mapping From Airborne Radiometry

    NASA Astrophysics Data System (ADS)

    Walker, J. P.; Gao, Y.; Cook, P. L. M.; Ye, N.

    2016-12-01

    Estuaries are critical ecosystems providing both ecological habitat and human amenity including boating and recreational fishing. Salinity gradients, caused by the mixing of fresh and salt water, exert an overwhelming control on estuarine ecology and biogeochemistry as well as being a key tracer for model calibration. At present, salinity monitoring within estuaries typically uses point measurements or underway boat-based methods, which makes sensing of localised phenomena such as upwelling of saline bottom water difficult. This study has pioneered the use of airborne radiometry (passive microwave) sensing as a new method to remotely quantify estuarine salinity, allowing rapid production of high resolution surface salinity maps. The airborne radiometry mapping was conducted for the Gippsland Lakes, the largest estuary in Australia, in February, July, October and November of 2015, using the Polarimetric L-band Microwave Radiometer (PLMR). Salinity was retrieved from the brightness temperature collected by PLMR with results validated against boat sampling conducted concurrently with each flight. Results showed that the retrieval accuracy of the radiative transfer model was better than 5 ppt for most flights. The spatial, temporal and seasonal variations of salinity observed in this study are also analysed and discussed.

  16. Hypertonic Saline Suppresses NADPH Oxidase-Dependent Neutrophil Extracellular Trap Formation and Promotes Apoptosis.

    PubMed

    Nadesalingam, Ajantha; Chen, Jacky H K; Farahvash, Armin; Khan, Meraj A

    2018-01-01

    solutions do not suppress NOX2-independent NETosis. Although hypertonic saline partially suppresses ionomycin-induced NETosis, it enhances A23187-induced NETosis, and it does not alter S. aureus -induced NETosis. Overall, this study determined that hypertonic saline suppresses NOX2-dependent NETosis induced by several agonists; in contrast, it has variable effects on neutrophil death induced by NOX2-independent NETosis agonists. These findings are important in understanding the regulation of NETosis and apoptosis in neutrophils.

  17. Salinity Management in Agriculture

    USDA-ARS?s Scientific Manuscript database

    Existing guidelines and standards for reclamation of saline soils and management to control salinity exist but have not been updated for over 25 years. In the past few years a looming water scarcity has resulted in questioning of the long term future of irrigation projects in arid and semi arid regi...

  18. Chloride and sulfate salinity effects on selenium accumulation by tall fescue. [Festuca arundinacea Schreb

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lin Wu; Zhang-Zhi Huang

    The discovery of high levels of Se in soil and water samples from the San Joaquin Valley, California, and of its responsibility for deformity and death of wildlife at Kesterson National Wildlife Refuge have renewed interest in the bioaccumulation of this element. Greenhouse nutrient solution culture and field experiments were conducted to examine the effects of Cl and SO{sub 4} salt on growth and Se accumulation in tall fescue (Festuca arundinacea Schreb.) cultivars Alta, Falcon, and Olympic. Sulfate salt substantially reduced growth inhibition and Se accumulation. Tall fescue from the field irrigated with water low in salinity had higher tissuemore » Se concentration than plants from the field irrigated with water high in salinity. No difference in tissue Se concentration was found among the three tall fescue cultivars; however, forage-type Alta produced the most shoot biomass and accumulated the most total Se. The soil irrigated with water high in salinity had 10 times higher Se concentration than soil irrigated with water low in salinity. The highest soil Se concentration was found in the top 15 cm of soil. Growing fescue for one year reduced soil Se by 50%. Selenium concentrations below 15-cm depth were lower and similar between the bare soil and the soil under tall fescue. Both the high and low salinity water irrigations did not cause high levels of Se accumulation by the tall fescue cultivars unless there was continual addition of Se into the system. This study generated important information for Se bioaccumulation management in soils with elevated salinity and Se levels.« less

  19. In vitro analysis of the physical properties of contact lens blister pack solutions.

    PubMed

    Menzies, Kara L; Jones, Lyndon

    2011-04-01

    Since the initial development of silicone hydrogels, many modifications to the bulk and surface properties of the lenses have been undertaken to improve the wettability and comfort of the lenses. Recently, manufacturers have incorporated various "wetting agents" or surface-active agents into the blister packaging solutions (BPSs) of the lenses to improve initial comfort of the lens on eye. The purpose of this study was to measure and compare the pH, surface tension (ST), viscosity, and osmolality of BPSs for a variety of silicone hydrogel and polyHEMA-based hydrogel lenses. In addition, two saline solutions were tested for comparison purposes. The pH, osmolality, ST, and viscosity were measured for the BPSs for lotrafilcon B and lotrafilcon A and lotrafilcon B with a "modified BPS" (m-lotrafilcon A, m-lotrafilcon B) (CIBA Vision, Duluth, GA); balafilcon A (Bausch & Lomb, Rochester, NY); galyfilcon A, senofilcon A, and narafilcon A (Johnson & Johnson, Jacksonville, FL); and comfilcon A and enfilcon A (CooperVision, Pleasanton, CA) and BPSs from two conventional polyHEMA-based materials-etafilcon A (Johnson & Johnson) and omafilcon A (CooperVision). The two saline solutions tested were Unisol (Alcon, Fort Worth, TX) and Softwear Saline (CIBA Vision). The pH results for the two saline solutions and all BPSs remained in the pH range of tears (6.6-7.8). The ST of the modified BPS was significantly lower (p < 0.01) than the original non-modified BPS. Viscosity measurements ranged between 0.90 and 1.00 cP for all BPSs and saline solutions, except for the modified BPS, which had significantly higher viscosities (p < 0.001). Osmolality measurements were not significantly different (p > 0.05) between BPSs made by the same manufacturer but were significantly different compared with BPSs made by different manufacturers (p < 0.05). The incorporation of wetting agents and surfactants into BPSs does alter the physical properties of the BPSs, which may have clinical implications

  20. Hypoxia-induced angiogenesis is increased by the controlled release of deferoxiamine from gelatin hydrogels.

    PubMed

    Saito, Takashi; Tabata, Yasuhiko

    2014-08-01

    The objective of this study is to design biodegradable hydrogels for the controlled release of deferoxiamine (DFO) and evaluate their biological activity. When the DFO was added to human umbilical vein endothelial cells cultured in 5.0% O2, the level of hypoxia-inducible factor-1α and vascular endothelial growth factor significantly increased compared with that without DFO. The expression of angiogenesis-related genes was accordingly increased by the DFO addition. An aqueous solution of mixed gelatin and DFO was freeze-dried, and dehydrothermally treated at 140°C for 24h to prepare a gelatin hydrogel incorporating DFO. In the release test with phosphate-buffered saline solution (PBS) at 37°C, an initial DFO release of 60% was observed, followed by no release. When placed in PBS containing collagenase, the hydrogel was enzymatically degraded with time, and consequently released DFO in a degradation-dependent manner. After the hydrogel incorporating DFO was injected intramuscularly into a mouse model of hind limb ischemia, the number of new blood vessels formed was significantly higher than that with free DFO and DFO-free hydrogel. It is concluded that the DFO-containing hydrogel shows promising for inducing angiogenesis locally. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  1. Design of a QA method to characterize submillimeter-sized PBS beam properties using a 2D ionization chamber array

    NASA Astrophysics Data System (ADS)

    Lin, Yuting; Bentefour, Hassan; Flanz, Jacob; Kooy, Hanne; Clasie, Benjamin

    2018-05-01

    Pencil beam scanning (PBS) periodic quality assurance (QA) programs ensure the beam delivered to patients is within technical specifications. Two critical specifications for PBS delivery are the beam width and position. The aim of this study is to investigate whether a 2D ionization chamber array, such as the MatriXX detector (IBA Dosimetry, Schwarzenbruck, Germany), can be used to characterize submillimeter-sized PBS beam properties. The motivation is to use standard equipment, which may have pixel spacing coarser than the pencil beam size, and simplify QA workflow. The MatriXX pixels are cylindrical in shape with 4.5 mm diameter and are spaced 7.62 mm from center to center. Two major effects limit the ability of using the MatriXX to measure the spot position and width accurately. The first effect is that too few pixels sample the Gaussian shaped pencil beam profile and the second effect is volume averaging of the Gaussian profile over the pixel sensitive volumes. We designed a method that overcomes both limitations and hence enables the use of the MatriXX to characterize sub-millimeter-sized PBS beam properties. This method uses a cross-like irradiation pattern that is designed to increase the number of sampling data points and a modified Gaussian fitting technique to correct for volume averaging effects. Detector signals were calculated in this study and random noise and setup errors were added to simulate measured data. With the techniques developed in this work, the MatriXX detector can be used to characterize the position and width of sub-millimeter, σ  =  0.7 mm, sized pencil beams with uncertainty better than 3% relative to σ. With the irradiation only covering 60% of the MatriXX, the position and width of σ  =  0.9 mm sized pencil beams can be determined with uncertainty better than 3% relative to σ. If one were to not use a cross-like irradiation pattern, then the position and width of σ  =  3.6 mm sized pencil beams

  2. Design of a QA method to characterize submillimeter-sized PBS beam properties using a 2D ionization chamber array.

    PubMed

    Lin, Yuting; Bentefour, Hassan; Flanz, Jacob; Kooy, Hanne; Clasie, Benjamin

    2018-05-15

    Pencil beam scanning (PBS) periodic quality assurance (QA) programs ensure the beam delivered to patients is within technical specifications. Two critical specifications for PBS delivery are the beam width and position. The aim of this study is to investigate whether a 2D ionization chamber array, such as the MatriXX detector (IBA Dosimetry, Schwarzenbruck, Germany), can be used to characterize submillimeter-sized PBS beam properties. The motivation is to use standard equipment, which may have pixel spacing coarser than the pencil beam size, and simplify QA workflow. The MatriXX pixels are cylindrical in shape with 4.5 mm diameter and are spaced 7.62 mm from center to center. Two major effects limit the ability of using the MatriXX to measure the spot position and width accurately. The first effect is that too few pixels sample the Gaussian shaped pencil beam profile and the second effect is volume averaging of the Gaussian profile over the pixel sensitive volumes. We designed a method that overcomes both limitations and hence enables the use of the MatriXX to characterize sub-millimeter-sized PBS beam properties. This method uses a cross-like irradiation pattern that is designed to increase the number of sampling data points and a modified Gaussian fitting technique to correct for volume averaging effects. Detector signals were calculated in this study and random noise and setup errors were added to simulate measured data. With the techniques developed in this work, the MatriXX detector can be used to characterize the position and width of sub-millimeter, σ  =  0.7 mm, sized pencil beams with uncertainty better than 3% relative to σ. With the irradiation only covering 60% of the MatriXX, the position and width of σ  =  0.9 mm sized pencil beams can be determined with uncertainty better than 3% relative to σ. If one were to not use a cross-like irradiation pattern, then the position and width of σ  =  3.6 mm sized pencil beams

  3. Soil transport parameters of potassium under a tropical saline soil condition using STANMOD

    NASA Astrophysics Data System (ADS)

    Suzanye da Silva Santos, Rafaelly; Honorio de Miranda, Jarbas; Previatello da Silva, Livia

    2015-04-01

    Environmental responsibility and concerning about the final destination of solutes in soil, so more studies allow a better understanding about the solutes behaviour in soil. Potassium is a macronutrient that is required in high concentrations, been an extremely important nutrient for all agricultural crops. It plays essential roles in physiological processes vital for plant growth, from protein synthesis to maintenance of plant water balance, and is available to plants dissolved in soil water while exchangeable K is loosely held on the exchange sites on the surface of clay particles. K will tend to be adsorbed onto the surface of negatively charged soil particles. Potassium uptake is vital for plant growth but in saline soils sodium competes with potassium for uptake across the plasma membrane of plant cells. This can result in high Na+:K+ ratios that reduce plant growth and eventually become toxic. This study aimed to obtain soil transport parameters of potassium in saline soil, such as: pore water velocity in soil (v), retardation factor (R), dispersivity (λ) and dispersion coefficient (D), in a disturbed sandy soil with different concentrations of potassium chlorate solution (KCl), which is one of the most common form of potassium fertilizer. The experiment was carried out using soil samples collected in a depth of 0 to 20 cm, applying potassium chlorate solution containing 28.6, 100, 200 and 500 mg L-1 of K. To obtain transport parameters, the data were adjusted with the software STANMOD. At low concentrations, interaction between potassium and soil occur more efficiently. It was observed that only the breakthrough curve prepared with solution of 500 mg L-1 reached the applied concentration, and the solution of 28.6 mg L-1 overestimated the parameters values. The STANMOD proved to be efficient in obtaining potassium transport parameters; KCl solution to be applied should be greater than 500 mg L-1; solutions with low concentrations tend to overestimate

  4. Effects of salinity on baldcypress seedlings: Physiological responses and their relation to salinity tolerance

    USGS Publications Warehouse

    Allen, J.A.; Chambers, J.L.; Pezeshki, S.R.

    1997-01-01

    Growth and physiological responses of 15 open-pollinated families of baldcypress (Taxodium distichum var. distichum) subjected to flooding with saline water were evaluated in this study. Ten of the families were from coastal sites in Louisiana and Alabama, USA that have elevated levels of soil-water salinity. The other five families were from inland, freshwater sites in Louisiana. Seedlings from all families tolerated flooding with water of low (2 g l-1) salinity. Differences in biomass among families became most apparent at the highest salinity levels (6 and 8 g l-1). Overall, increasing salinity reduced leaf biomass more than root biomass, which in turn was reduced more than stem biomass. A subset of seedlings from the main greenhouse experiment was periodically placed indoors under artificial light, and measurements were made of gas exchange and leaf water potential. Also, tissue concentrations of Cl-, Na+, K+, and Ca2+ were determined at the end of the greenhouse experiment. Significant intraspecific variation was found for nearly all the physiological parameters evaluated, but only leaf concentrations of Na+ and Cl- were correlated with an index of family-level differences in salt tolerance.

  5. Physiological and biochemical perspectives of non-salt tolerant plants during bacterial interaction against soil salinity.

    PubMed

    Radhakrishnan, Ramalingam; Baek, Kwang Hyun

    2017-07-01

    Climatic changes on earth affect the soil quality of agricultural lands, especially by increasing salt deposition in soil, which results in soil salinity. Soil salinity is a major challenge to growth and reproduction among glycophytes (including all crop plants). Soil bacteria present in the rhizosphere and/or roots naturally protect plants from the adverse effects of soil salinity by reprogramming the stress-induced physiological changes in plants. Bacteria can enrich the soil with major nutrients (nitrogen, phosphorus, and potassium) in a form easily available to plants and prevent the transport of excess sodium to roots (exopolysaccharides secreted by bacteria bind with sodium ions) for maintaining ionic balance and water potential in cells. Salinity also affects plant growth regulators and suppresses seed germination and root and shoot growth. Bacterial secretion of indole-3-acetic acid and gibberellins compensates for the salt-induced hormonal decrease in plants, and bacterial 1-aminocyclopropane-1-carboxylate (ACC) deaminase synthesis decreases ethylene production to stimulate plant growth. Furthermore, bacteria modulate the redox state of salinity-affected plants by enhancing antioxidants and polyamines, which leads to increased photosynthetic efficiency. Bacteria-induced accumulation of compatible solutes in stressed plants regulates plant cellular activities and prevents salt stress damage. Plant-bacterial interaction reprograms the expression of salt stress-responsive genes and proteins in salinity-affected plants, resulting in a precise stress mitigation metabolism as a defense mechanism. Soil bacteria increase the fertility of soil and regulate the plant functions to prevent the salinity effects in glycophytes. This review explains the current understanding about the physiological changes induced in glycophytes during bacterial interaction to alleviate the adverse effects of soil salinity stress. Copyright © 2017 Elsevier Masson SAS. All rights

  6. Clarification of the recovery mechanism of Escherichia coli after hydrostatic pressure treatment

    NASA Astrophysics Data System (ADS)

    Ohshima, Shuto; Nomura, Kazuki; Iwahashi, Hitoshi

    2013-06-01

    High hydrostatic pressure (HP) technology has gained more attention as a non-thermal food pasteurization technology. Recently, a limitation of the HP technology was reported by Koseki and Yamamoto [Recovery of Escherichia coli ATCC 25922 in phosphate buffered saline after treatment with high hydrostatic pressure. Int. J. Food Microbiol. 2006;110:108-111], who completely recovered Escherichia coli species after HP treatment. We investigated the recovery mechanism of E. coli after HP treatment. The cells were treated with 200-300 MPa at 0-25°C for 24 h. The HP-treated E. coli was recovered in phosphate-buffered saline (PBS) during 120 h of incubation at 25°C, confirming the results reported by them. However, E. coli did not grow in PBS but grew with inactivated cells in PBS. In addition, the results of our "population size experiments" demonstrated that the recovery of E. coli cells depended on both the degree of pressure and the population size. These results suggest that some portion of cells recovered from the damage and then grew by using inactivated cells.

  7. Optimal control solutions to sodic soil reclamation

    NASA Astrophysics Data System (ADS)

    Mau, Yair; Porporato, Amilcare

    2016-05-01

    We study the reclamation process of a sodic soil by irrigation with water amended with calcium cations. In order to explore the entire range of time-dependent strategies, this task is framed as an optimal control problem, where the amendment rate is the control and the total rehabilitation time is the quantity to be minimized. We use a minimalist model of vertically averaged soil salinity and sodicity, in which the main feedback controlling the dynamics is the nonlinear coupling of soil water and exchange complex, given by the Gapon equation. We show that the optimal solution is a bang-bang control strategy, where the amendment rate is discontinuously switched along the process from a maximum value to zero. The solution enables a reduction in remediation time of about 50%, compared with the continuous use of good-quality irrigation water. Because of its general structure, the bang-bang solution is also shown to work for the reclamation of other soil conditions, such as saline-sodic soils. The novelty in our modeling approach is the capability of searching the entire "strategy space" for optimal time-dependent protocols. The optimal solutions found for the minimalist model can be then fine-tuned by experiments and numerical simulations, applicable to realistic conditions that include spatial variability and heterogeneities.

  8. New steady-state models for water-limited cropping systems using saline irrigation waters: Analytical solutions and applications

    USDA-ARS?s Scientific Manuscript database

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mod...

  9. New steady-state models for water-limited cropping systems using saline irrigation waters: Analytical solutions and applications

    USDA-ARS?s Scientific Manuscript database

    Due to the diminishing availability of good quality water for irrigation, it is increasingly important that irrigation and salinity management tools be able to target submaximal crop yields and support the use of marginal quality waters. In this work, we present a steady-state irrigated systems mode...

  10. The extent of variation in salinity tolerance of the minicore collection of finger millet (Eleusine coracana L. Gaertn.) germplasm.

    PubMed

    Krishnamurthy, Lakshmanan; Upadhyaya, Hari Deo; Purushothaman, Ramamoorthy; Gowda, Cholenahalli Lakkegowda Laxmipathi; Kashiwagi, Junichi; Dwivedi, Sangam Lal; Singh, Sube; Vadez, Vincent

    2014-10-01

    Finger millet (Eleusine coracana L. Gaertn.) ranks third in production among the dry land cereals. It is widely cultivated in Africa and South Asia where soil salinization is a major production constraint. It is a potential crop for salt affected soils. To identify salt tolerant germplasm, the minicore finger millet germplasm (n=80) was screened for grain yield performance in a soil saturated with NaCl solution of 100 or 125mM. Genotype effect was significant for most traits, while salinity×genotype interaction was significant only in one year. Salinity delayed phenology, marginally reduced shoot biomass and grain yield. There was a large range of genotypic variation in grain yield under salinity and other traits. The yield loss was higher in accessions with prolific growth and yield potential was associated with saline yields. Based on saline yields, accessions were grouped in to four groups and the top tolerant group had 22 accessions with IE 4797 remaining at the top. Salinity had no adverse impact on grain yield of five accessions. Root anatomy in selected genotype of pearl and finger millet showed presence of porous cortex and well fortified endodermis in finger millet that can exclude Na(+) and enhance N absorption. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. Cognitive changes after saline or plasmalyte infusion in healthy volunteers: a multiple blinded, randomized, cross-over trial.

    PubMed

    Story, David A; Lees, Lucy; Weinberg, Laurence; Teoh, Soon-Yee; Lee, Katherine J; Velissaris, Sarah; Bellomo, Rinaldo; Wilson, Sarah J

    2013-09-01

    In an incidental finding, during a study of plasma chemistry after crystalloid infusion, participants reported subjective cognitive changes, particularly slower thinking, after saline but not Hartmann's (Ringer's lactate) solution. The authors tested the hypothesis that saline infusion would produce greater adverse cognitive changes than Plasmalyte infusion. The authors conducted a randomized, cross-over, multiple blinded study of healthy adult volunteers. On separate days, participants received 30 ml/kg over 1 h of either 0.9% saline or Plasmalyte with the order randomly allocated. Plasma chemistry was tested on venous samples. As part of a battery of cognitive tests our primary endpoint was the reaction time index after infusion. The authors studied 25 participants. Plasma chloride was greater after saline than after Plasmalyte: mean difference 5.4 mM (95% CI, 4.1-6.6 mM; P < 0.001). Saline was also associated with greater metabolic acidosis: base-excess 2.5 mM more negative (95% CI, 1.9-3.0 mM more negative; P < 0.001). There was no evidence of a difference in the reaction time index between the two interventions: mean reaction time index 394 ms (SD, 72) after saline versus 385 ms (SD, 55) after Plasmalyte. Difference: saline 9 ms slower (95% CI, 30 ms slower to 12 ms faster; P = 0.39). There were minimal differences in the other cognitive and mood tests. Despite expected differences in plasma chemistry, the authors found that measures of cognition did not differ after infusions of Plasmalyte or saline.

  12. Preliminary study on the dynamics of heavy metals in saline wastewater treated in constructed wetland mesocosms or microcosms filled with porous slag.

    PubMed

    Liang, Yinxiu; Zhu, Hui; Bañuelos, Gary; Xu, Yingying; Yan, Baixing; Cheng, Xianwei

    2018-06-07

    This study aims to evaluate the practical potential of using constructed wetlands (CWs) for treating saline wastewater containing various heavy metals. The results demonstrated that CWs growing Canna indica with porous slag as substrate could efficiently remove heavy metals (Cu, Zn, Cd, and Pb) from saline wastewater at an electrical conductivity (EC) of 7 mS/cm, especially under low influent load. Salts with salinity level (characterized as EC) of 30 mS/cm suppressed the removal of some heavy metals, dependent on heavy metal species and their influent concentrations. The presence of salts in CWs can improve the accumulation of Cu, Zn, and Pb in plant tissues as compared to control treatment, irrespective of metal concentrations in solution. The influence of salts on Cd accumulation depended on both salinity levels and Cd concentrations in solution. Although more heavy metals were accumulated in roots than in shoots, the harvesting of aboveground plant materials is still efficient addition for heavy metal removal due to the greater biomass and growth rate of aboveground plant material. Furthermore, replacing all plants instead of preserving roots from harvested plants in CWs over a period of time is essential for heavy metal removal, because the continued accumulation by roots can be inhibited by the increasing accumulated heavy metals from saline wastewater.

  13. Water and mineral relations of Atriplex canescens and A. cuneata on saline processed oil shale

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Richardson, S.G.

    1979-01-01

    Growth, mineral uptake and water relations of Atriplex canescens and A. cuneata, both native to the arid oil shale region of northeastern Utah, were studied in the greenhouse and laboratory as affected by various salinity levels and specific ions in processed oil shale. Salinity of the shale was manipulated by moistening leached processed oil shale to near field capacity (20% H/sub 2/O by weight) with solutions of shale leachate, sodium sulfate, magnesium sulfate or sodium chloride at equiosmotic concentrations ranging from 0 to -30 bars. Although shale salinity did not affect osmotic adjustment, zero turgor points of A. canescens becamemore » more negative with reductions in shale moisture percentage. Differences in plant growth due to differet ions in the soil solution could not be explained by effects on osmotic adjustment. However, greater growth of A. canescens in Na/sub 2/SO/sub 4/ treated than MgSO/sub 4/ treated leached shale was associated with greater leaf succulence, greater lamina lengths and lamina widths and lower diffusive leaf resistances. Potassium added to leached and unleached processed oil shale increased shoot and root biomass production, shoot/root ratio, leaf K content, and water use efficiency of a sodium-excluding Atriplex canescens biotype but did not increase growth of a sodium-accumulating biotype.« less

  14. Structure, transport and photoconductance of PbS quantum dot monolayers functionalized with a copper phthalocyanine derivative.

    PubMed

    André, A; Theurer, C; Lauth, J; Maiti, S; Hodas, M; Samadi Khoshkhoo, M; Kinge, S; Meixner, A J; Schreiber, F; Siebbeles, L D A; Braun, K; Scheele, M

    2017-01-31

    We simultaneously surface-functionalize PbS nanocrystals with Cu 4,4',4'',4'''-tetraaminophthalocyanine and assemble this hybrid material into macroscopic monolayers. Electron microscopy and X-ray scattering reveal a granular mesocrystalline structure with strong coherence between the atomic lattice and the superlattice of nanocrystals within each domain. Terahertz spectroscopy and field-effect transistor measurements indicate efficient coupling of holes throughout the hybrid thin film, in conjunction with a pronounced photoresponse. We demonstrate the potential of this material for optoelectronic applications by fabricating a light-effect transistor.

  15. Spatial variability of soil salinity in coastal saline soil at different scales in the Yellow River Delta, China.

    PubMed

    Wang, Zhuoran; Zhao, Gengxing; Gao, Mingxiu; Chang, Chunyan

    2017-02-01

    The objectives of this study were to explore the spatial variability of soil salinity in coastal saline soil at macro, meso and micro scales in the Yellow River delta, China. Soil electrical conductivities (ECs) were measured at 0-15, 15-30, 30-45 and 45-60 cm soil depths at 49 sampling sites during November 9 to 11, 2013. Soil salinity was converted from soil ECs based on laboratory analyses. Our results indicated that at the macro scale, soil salinity was high with strong variability in each soil layer, and the content increased and the variability weakened with increasing soil depth. From east to west in the region, the farther away from the sea, the lower the soil salinity was. The degrees of soil salinization in three deeper soil layers are 1.14, 1.24 and 1.40 times higher than that in the surface soil. At the meso scale, the sequence of soil salinity in different topographies, soil texture and vegetation decreased, respectively, as follows: depression >flatland >hillock >batture; sandy loam >light loam >medium loam >heavy loam >clay; bare land >suaeda salsa >reed >cogongrass >cotton >paddy >winter wheat. At the micro scale, soil salinity changed with elevation in natural micro-topography and with anthropogenic activities in cultivated land. As the study area narrowed down to different scales, the spatial variability of soil salinity weakened gradually in cultivated land and salt wasteland except the bare land.

  16. Study of Exciton Hopping Transport in PbS Colloidal Quantum Dot Thin Films Using Frequency- and Temperature-Scanned Photocarrier Radiometry

    NASA Astrophysics Data System (ADS)

    Hu, Lilei; Mandelis, Andreas; Melnikov, Alexander; Lan, Xinzheng; Hoogland, Sjoerd; Sargent, Edward H.

    2017-01-01

    Solution-processed colloidal quantum dots (CQDs) are promising materials for realizing low-cost, large-area, and flexible photovoltaic devices. The study of charge carrier transport in quantum dot solids is essential for understanding energy conversion mechanisms. Recently, solution-processed two-layer oleic-acid-capped PbS CQD solar cells with one layer treated with tetrabutylammonium iodide (TBAI) serving as the main light-absorbing layer and the other treated with 1,2-ethanedithiol (EDT) acting as an electron-blocking/hole-extraction layer were reported. These solar cells demonstrated a significant improvement in power conversion efficiency of 8.55% and long-term air stability. Coupled with photocarrier radiometry measurements, this work used a new trap-state mediated exciton hopping transport model, specifically for CQD thin films, to unveil and quantify exciton transport mechanisms through the extraction of hopping transport parameters including exciton lifetimes, hopping diffusivity, exciton detrapping time, and trap-state density. It is shown that PbS-TBAI has higher trap-state density than PbS-EDT that results in higher PbS-EDT exciton lifetimes. Hopping diffusivities of both CQD thin film types show similar temperature dependence, particularly higher temperatures yield higher hopping diffusivity. The higher diffusivity of PbS-TBAI compared with PbS-EDT indicates that PbS-TBAI is a much better photovoltaic material than PbS-EDT. Furthermore, PCR temperature spectra and deep-level photothermal spectroscopy provided additional insights to CQD surface trap states: PbS-TBAI thin films exhibit a single dominant trap level, while PbS-EDT films with lower trap-state densities show multiple trap levels.

  17. Optimization of rhamnolipid production from Pseudomonas aeruginosa PBS towards application for microbial enhanced oil recovery.

    PubMed

    Sharma, Rajni; Singh, Jagdish; Verma, Neelam

    2018-01-01

    The present work reveals the potential of biosurfactant producing P. aeruginosa PBS for microbial enhanced oil recovery (MEOR). The biosurfactant production medium and culture conditions were optimized using response surface methodology. The optimization of media components and process parameters was consecutively executed in two sets of experimental runs designed by central composite rotatable design (CCRD). The maximum biosurfactant yield was attained with 2% fresh inoculum of P. aeruginosa PBS in minimal salt medium (pH 7), possessing 2.17% sodium citrate as C-source and 0.5% yeast extract as N-source, after 48 h upon incubation at 30 °C/150 rpm. Under optimum conditions, biosurfactant yield was increased more than threefold and turned out to be 2.65 g/L as compared to 0.82 g/L under previous conditions. The biosurfactant was characterized as a glycolipid comprising of four rhamnolipid homologs (RhaRhaC 10 C 10 , RhaRhaC 8 C 10 , RhaRhaC 12 C 10 /RhaRhaC 10 C 12 , RhaC 10 C 10 ) by thin layer chromatography, fourier transform infrared spectroscopy, nuclear magnetic resonance and mass spectrometry. The produced biosurfactant was highly efficient for oil recovery application showing extreme reduction in surface tension of medium (71.80 to 23.76 mN/m), immense hydrocarbons emulsification capacity (50-60%) and greater stability at wide range of temperature (4-100 °C) and pH (4-10) along with an excellent (56.18 ± 1.59%) additional oil recovery in sand-pack column lab test.

  18. pH Sensing Properties of Flexible, Bias-Free Graphene Microelectrodes in Complex Fluids: From Phosphate Buffer Solution to Human Serum.

    PubMed

    Ping, Jinglei; Blum, Jacquelyn E; Vishnubhotla, Ramya; Vrudhula, Amey; Naylor, Carl H; Gao, Zhaoli; Saven, Jeffery G; Johnson, Alan T Charlie

    2017-08-01

    Advances in techniques for monitoring pH in complex fluids can have a significant impact on analytical and biomedical applications. This study develops flexible graphene microelectrodes (GEs) for rapid (<5 s), very-low-power (femtowatt) detection of the pH of complex biofluids by measuring real-time Faradaic charge transfer between the GE and a solution at zero electrical bias. For an idealized sample of phosphate buffer solution (PBS), the Faradaic current is varied monotonically and systematically with the pH, with a resolution of ≈0.2 pH unit. The current-pH dependence is well described by a hybrid analytical-computational model, where the electric double layer derives from an intrinsic, pH-independent (positive) charge associated with the graphene-water interface and ionizable (negative) charged groups. For ferritin solution, the relative Faradaic current, defined as the difference between the measured current response and a baseline response due to PBS, shows a strong signal associated with ferritin disassembly and the release of ferric ions at pH ≈2.0. For samples of human serum, the Faradaic current shows a reproducible rapid (<20 s) response to pH. By combining the Faradaic current and real-time current variation, the methodology is potentially suitable for use to detect tumor-induced changes in extracellular pH. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Bacterial responses to fluctuations and extremes in temperature and brine salinity at the surface of Arctic winter sea ice.

    PubMed

    Ewert, Marcela; Deming, Jody W

    2014-08-01

    Wintertime measurements near Barrow, Alaska, showed that bacteria near the surface of first-year sea ice and in overlying saline snow experience more extreme temperatures and salinities, and wider fluctuations in both parameters, than bacteria deeper in the ice. To examine impacts of such conditions on bacterial survival, two Arctic isolates with different environmental tolerances were subjected to winter-freezing conditions, with and without the presence of organic solutes involved in osmoprotection: proline, choline, or glycine betaine. Obligate psychrophile Colwellia psychrerythraea strain 34H suffered cell losses under all treatments, with maximal loss after 15-day exposure to temperatures fluctuating between -7 and -25 °C. Osmoprotectants significantly reduced the losses, implying that salinity rather than temperature extremes presents the greater stress for this organism. In contrast, psychrotolerant Psychrobacter sp. strain 7E underwent miniaturization and fragmentation under both fluctuating and stable-freezing conditions, with cell numbers increasing in most cases, implying a different survival strategy that may include enhanced dispersal. Thus, the composition and abundance of the bacterial community that survives in winter sea ice may depend on the extent to which overlying snow buffers against extreme temperature and salinity conditions and on the availability of solutes that mitigate osmotic shock, especially during melting. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  20. Mechanical properties and bio-tribological behaviors of novel beta-Zr-type Zr-Al-Fe-Nb alloys for biomedical applications.

    PubMed

    Hua, Nengbin; Chen, Wenzhe; Zhang, Lei; Li, Guanghui; Liao, Zhenlong; Lin, Yan

    2017-07-01

    The present study prepares novel Zr 70+x Al 5 Fe 15-x Nb 10 (x=0, 5) alloys by arc-melting for potential biomedical application. The mechanical properties and bio-tribological behaviors of the Zr-based alloys are evaluated and compared with biomedical pure Zr. The as-prepared alloys exhibit a microstructure containing a micrometer-sized dendritic beta-Zr phase dispersed in a Zr 2 Fe-typed matrix. It is found that increasing the content of Zr is favorable for the mechanical compatibility with a combination of low Young's modulus, large plasticity, and high compressive strength. The wear resistance of the Zr-Al-Fe-Nb alloys in air and phosphate buffer saline (PBS) solution is superior to that of pure Zr. The wear mechanism of Zr-based alloys sliding in air is controlled by oxidation and abrasive wear whereas that sliding in PBS is controlled by synergistic effects of the abrasive and corrosive wear. Electrochemical measurements demonstrate that the Zr-based alloys are corrosion resistant in PBS. Their bio-corrosion resistance is improved with the increase in Zr content, which is attributed to the enrichment in Zr and decrease in Al concentration in the surface passive film of alloys. The Zr 75 Al 5 Fe 10 Nb 10 exhibits the best corrosion resistance in PBS, which contributes to its superior wear resistance in a simulated body environment. The combination of good mechanical properties, corrosion resistance, and biotribological behaviors of the Zr-Al-Fe-Nb alloys offers them potential advantages in biomedical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. In vitro corrosion study by EIS of a nickel-free stainless steel for orthopaedic applications.

    PubMed

    Rondelli, G; Torricelli, P; Fini, M; Giardino, R

    2005-03-01

    The electrochemical impedance spectroscopy (EIS) technique was used for the study of the electrochemical behaviour of Ni-free austenitic stainless steel for orthopaedic applications. Experiments were carried out using four different test solutions: (i) phosphate-buffered saline (PBS), (ii) minimum essential medium (MEM), (iii) MEM + 10% fetal calf serum (FCS), (iv) MEM + 10% fetal calf serum + L929 fibroblast cell line (Cell). Bode-phase spectra showed the presence of two maxima and were fitted with an equivalent circuit characterized by two parallel combinations (Resistance, Constant Phase Element). The (R(1), CPE(1)) branch was assigned to the inner compact passive film and the (R(2), CPE(2)) branch to the external porous film. The resistance of the inner film R(1), here directly related to the material's uniform corrosion resistance, raised with the immersion time and increased in the following order: PBS

  2. Gold nanoparticle incorporated polymer/bioactive glass composite for controlled drug delivery application.

    PubMed

    Jayalekshmi, A C; Sharma, Chandra P

    2015-02-01

    The present study discusses the development of a biodegradable polymer encapsulated-nanogold incorporated-bioactive glass composite (AuPBG) by a low-temperature method. The composite was analyzed by atomic force microscopy (AFM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetry (TG), fluorescence and dissolution analysis. The composite exhibited aggregation behaviour in solid and solution states and exhibited negative zeta potential (-13.3 ± 1.4 mV). The composite exhibited fast degradation starting from the 5(th) day onwards in phosphate buffered saline (PBS) for a period of 14 days. The composite showed fluorescence quenching effect at pH 7 and the fluorescence recovered at pH 5. The composite has been found to be suitable for the release of doxorubicin at high rates at acidic pH (∼ 5) which is the intracellular pH of tumour cells. The drug loading ratio is also high and it exhibited a controlled release for a period of 8 days in PBS. The system serves as a promising material for targeted drug delivery applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. High-performance ionic diode membrane for salinity gradient power generation.

    PubMed

    Gao, Jun; Guo, Wei; Feng, Dan; Wang, Huanting; Zhao, Dongyuan; Jiang, Lei

    2014-09-03

    Salinity difference between seawater and river water is a sustainable energy resource that catches eyes of the public and the investors in the background of energy crisis. To capture this energy, interdisciplinary efforts from chemistry, materials science, environmental science, and nanotechnology have been made to create efficient and economically viable energy conversion methods and materials. Beyond conventional membrane-based processes, technological breakthroughs in harvesting salinity gradient power from natural waters are expected to emerge from the novel fluidic transport phenomena on the nanoscale. A major challenge toward real-world applications is to extrapolate existing single-channel devices to macroscopic materials. Here, we report a membrane-scale nanofluidic device with asymmetric structure, chemical composition, and surface charge polarity, termed ionic diode membrane (IDM), for harvesting electric power from salinity gradient. The IDM comprises heterojunctions between mesoporous carbon (pore size ∼7 nm, negatively charged) and macroporous alumina (pore size ∼80 nm, positively charged). The meso-/macroporous membrane rectifies the ionic current with distinctly high ratio of ca. 450 and keeps on rectifying in high-concentration electrolytes, even in saturated solution. The selective and rectified ion transport furthermore sheds light on salinity-gradient power generation. By mixing artificial seawater and river water through the IDM, substantially high power density of up to 3.46 W/m(2) is discovered, which largely outperforms some commercial ion-exchange membranes. A theoretical model based on coupled Poisson and Nernst-Planck equations is established to quantitatively explain the experimental observations and get insights into the underlying mechanism. The macroscopic and asymmetric nanofluidic structure anticipates wide potentials for sustainable power generation, water purification, and desalination.

  4. Effect of bioactive glass-containing resin composite on dentin remineralization.

    PubMed

    Lee, Myoung Geun; Jang, Ji-Hyun; Ferracane, Jack L; Davis, Harry; Bae, Han Eul; Choi, Dongseok; Kim, Duck-Su

    2018-05-25

    The purpose of this study was to evaluate the effect of bioactive glass (BAG)-containing composite on dentin remineralization. Sixty-six dentin disks with 3 mm thickness were prepared from thirty-three bovine incisors. The following six experimental groups were prepared according to type of composite (control and experimental) and storage solutions (simulated body fluid [SBF] and phosphate-buffered saline [PBS]): 1 (undemineralized); 2 (demineralized); 3 (demineralized with control in SBF); 4 (demineralized with control in PBS); 5 (demineralized with experimental composite in SBF); and 6 (demineralized with experimental composite in PBS). BAG65S (65% Si, 31% Ca, and 4% P) was prepared via the sol-gel method. The control composite was made with a 50:50 Bis-GMA:TEGDMA resin matrix, 57 wt% strontium glass, and 15 wt% aerosol silica. The experimental composite had the same resin and filler, but with 15 wt% BAG65S replacing the aerosol silica. For groups 3-6, composite disks (20 × 10 × 2 mm) were prepared and approximated to the dentin disks and stored in PBS or SBF for 2 weeks. Micro-hardness measurements, attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) and field-emission scanning electron microscopy (FE-SEM) was investigated. The experimental BAG-containing composite significantly increased the micro-hardness of the adjacent demineralized dentin. ATR-FTIR revealed calcium phosphate peaks on the surface of the groups which used experimental composite. FE-SEM revealed surface deposits partially occluding the dentin surface. No significant difference was found between SBF and PBS storage. BAG-containing composites placed in close proximity can partially remineralize adjacent demineralized dentin. Copyright © 2018. Published by Elsevier Ltd.

  5. Comparative Evaluation of Three Homogenization Methods for Isolating Middle East Respiratory Syndrome Coronavirus Nucleic Acids From Sputum Samples for Real-Time Reverse Transcription PCR

    PubMed Central

    Yong, Dongeun; Ki, Chang-Seok; Kim, Jae-Seok; Seong, Moon-Woo; Lee, Hyukmin

    2016-01-01

    Background Real-time reverse transcription PCR (rRT-PCR) of sputum samples is commonly used to diagnose Middle East respiratory syndrome coronavirus (MERS-CoV) infection. Owing to the difficulty of extracting RNA from sputum containing mucus, sputum homogenization is desirable prior to nucleic acid isolation. We determined optimal homogenization methods for isolating viral nucleic acids from sputum. Methods We evaluated the following three sputum-homogenization methods: proteinase K and DNase I (PK-DNase) treatment, phosphate-buffered saline (PBS) treatment, and N-acetyl-L-cysteine and sodium citrate (NALC) treatment. Sputum samples were spiked with inactivated MERS-CoV culture isolates. RNA was extracted from pretreated, spiked samples using the easyMAG system (bioMérieux, France). Extracted RNAs were then subjected to rRT-PCR for MERS-CoV diagnosis (DiaPlex Q MERS-coronavirus, SolGent, Korea). Results While analyzing 15 spiked sputum samples prepared in technical duplicate, false-negative results were obtained with five (16.7%) and four samples (13.3%), respectively, by using the PBS and NALC methods. The range of threshold cycle (Ct) values observed when detecting upE in sputum samples was 31.1–35.4 with the PK-DNase method, 34.7–39.0 with the PBS method, and 33.9–38.6 with the NALC method. Compared with the control, which were prepared by adding a one-tenth volume of 1:1,000 diluted viral culture to PBS solution, the ranges of Ct values obtained by the PBS and NALC methods differed significantly from the mean control Ct of 33.2 (both P<0.0001). Conclusions The PK-DNase method is suitable for homogenizing sputum samples prior to RNA extraction. PMID:27374711

  6. Infra-red photoresponse of mesoscopic NiO-based solar cells sensitized with PbS quantum dot

    PubMed Central

    Raissi, Mahfoudh; Pellegrin, Yann; Jobic, Stéphane; Boujtita, Mohammed; Odobel, Fabrice

    2016-01-01

    Sensitized NiO based photocathode is a new field of investigation with increasing scientific interest in relation with the development of tandem dye-sensitized solar cells (photovoltaic) and dye-sensitized photoelectrosynthetic cells (solar fuel). We demonstrate herein that PbS quantum dots (QDs) represent promising inorganic sensitizers for NiO-based quantum dot-sensitized solar cells (QDSSCs). The solar cell sensitized with PbS quantum dot exhibits significantly higher photoconversion efficiency than solar cells sensitized with a classical and efficient molecular sensitizer (P1 dye = 4-(Bis-{4-[5-(2,2-dicyano-vinyl)-thiophene-2-yl]-phenyl}-amino)-benzoic acid). Furthermore, the system features an IPCE (Incident Photon-to-Current Efficiency) spectrum that spreads into the infra-red region, reaching operating wavelengths of 950 nm. The QDSSC photoelectrochemical device works with the complexes tris(4,4′-ditert-butyl-2,2′-bipyridine)cobalt(III/II) redox mediators, underscoring the formation of a long-lived charge-separated state. The electrochemical impedance spectrocopy measurements are consistent with a high packing of the QDs upon the NiO surface, the high density of which limits the access of the electrolyte and results in favorable light absorption cross-sections and a significant hole lifetime. These notable results highlight the potential of NiO-based photocathodes sensitized with quantum dots for accessing and exploiting the low-energy part of the solar spectrum in photovoltaic and photocatalysis applications. PMID:27125454

  7. Last Glacial Maximum Salinity Reconstruction

    NASA Astrophysics Data System (ADS)

    Homola, K.; Spivack, A. J.

    2016-12-01

    It has been previously demonstrated that salinity can be reconstructed from sediment porewater. The goal of our study is to reconstruct high precision salinity during the Last Glacial Maximum (LGM). Salinity is usually determined at high precision via conductivity, which requires a larger volume of water than can be extracted from a sediment core, or via chloride titration, which yields lower than ideal precision. It has been demonstrated for water column samples that high precision density measurements can be used to determine salinity at the precision of a conductivity measurement using the equation of state of seawater. However, water column seawater has a relatively constant composition, in contrast to porewater, where variations from standard seawater composition occur. These deviations, which affect the equation of state, must be corrected for through precise measurements of each ion's concentration and knowledge of apparent partial molar density in seawater. We have developed a density-based method for determining porewater salinity that requires only 5 mL of sample, achieving density precisions of 10-6 g/mL. We have applied this method to porewater samples extracted from long cores collected along a N-S transect across the western North Atlantic (R/V Knorr cruise KN223). Density was determined to a precision of 2.3x10-6 g/mL, which translates to salinity uncertainty of 0.002 gms/kg if the effect of differences in composition is well constrained. Concentrations of anions (Cl-, and SO4-2) and cations (Na+, Mg+, Ca+2, and K+) were measured. To correct salinities at the precision required to unravel LGM Meridional Overturning Circulation, our ion precisions must be better than 0.1% for SO4-/Cl- and Mg+/Na+, and 0.4% for Ca+/Na+, and K+/Na+. Alkalinity, pH and Dissolved Inorganic Carbon of the porewater were determined to precisions better than 4% when ratioed to Cl-, and used to calculate HCO3-, and CO3-2. Apparent partial molar densities in seawater were

  8. Study on improving viscosity of polymer solution based on complex reaction

    NASA Astrophysics Data System (ADS)

    Sun, G.; Li, D.; Zhang, D.; Xu, T. H.

    2018-05-01

    The current status of polymer flooding Technology on high salinity oil reservoir is not ideal. A method for increasing the viscosity of polymer solutions is urgently needed. This paper systematically studied the effect of ions with different mass concentrations on the viscosity of polymer solutions. Based on the theory of complex reaction, a countermeasure of increasing viscosity of polymer solution under conditions of high salinity reservoir was proposed. The results show that Ca2+ and Mg2+ have greater influence on the solution viscosity than K+ and Na+. When the concentration of divalent ions increases from 0 mg/L to 80 mg/L, the viscosity of the polymer solution decreases from 210 mPa·s to 38.6 mPa·s. The viscosity of the polymer solution prepared from the sewage treated with the Na2C2O4 increased by 25.3%. Atomic force microscopy test results show that Na2C2O4 can effectively shield the divalent metal ions, so that the polymer molecules in the solution stretch more, thereby increasing the solution viscosity. Atomic force microscopy test results show that Na2C2O4 can effectively shield the divalent metal ions, so that the polymer molecules in the solution stretch more, thereby increasing the solution viscosity.

  9. Evaluating physiological responses of plants to salinity stress

    PubMed Central

    Negrão, S.; Schmöckel, S. M.; Tester, M.

    2017-01-01

    Background Because soil salinity is a major abiotic constraint affecting crop yield, much research has been conducted to develop plants with improved salinity tolerance. Salinity stress impacts many aspects of a plant’s physiology, making it difficult to study in toto. Instead, it is more tractable to dissect the plant’s response into traits that are hypothesized to be involved in the overall tolerance of the plant to salinity. Scope and conclusions We discuss how to quantify the impact of salinity on different traits, such as relative growth rate, water relations, transpiration, transpiration use efficiency, ionic relations, photosynthesis, senescence, yield and yield components. We also suggest some guidelines to assist with the selection of appropriate experimental systems, imposition of salinity stress, and obtaining and analysing relevant physiological data using appropriate indices. We illustrate how these indices can be used to identify relationships amongst the proposed traits to identify which traits are the most important contributors to salinity tolerance. Salinity tolerance is complex and involves many genes, but progress has been made in studying the mechanisms underlying a plant’s response to salinity. Nevertheless, several previous studies on salinity tolerance could have benefited from improved experimental design. We hope that this paper will provide pertinent information to researchers on performing proficient assays and interpreting results from salinity tolerance experiments. PMID:27707746

  10. Salinity control in a clay soil beneath an orchard irrigated with treated waste water in the presence of a high water table: A numerical study

    NASA Astrophysics Data System (ADS)

    Russo, David; Laufer, Asher; Bardhan, Gopali; Levy, Guy J.

    2015-12-01

    A citrus orchard planted on a structured, clay soil associated with a high water table, irrigated by drip irrigation system using treated waste water (TWW) and local well water (LWW) was considered here. The scope of the present study was to analyze transport of mixed-ion, interacting salts in a combined vadose zone-groundwater flow system focusing on the following issues: (i) long-term effects of irrigation with TWW on the response of the flow system, identifying the main factors (e.g., soil salinity, soil sodicity) that control these effects, and (ii) salinity control aiming at improving both crop productivity and groundwater quality. To pursue this two-fold goal, 3-D numerical simulations of field-scale flow and transport were performed for an extended period of time, considering realistic features of the soil, water table, crop, weather and irrigation, and the coupling between the flow and the transport through the dependence of the soil hydraulic functions, K(ψ) and θ(ψ), on soil solution concentration C, and sodium adsorption ratio, SAR. Results of the analyses suggest that in the case studied, the long-term effect of irrigation with TWW on the response of the flow system is attributed to the enhanced salinity of the TWW, and not to the increase in soil sodicity. The latter findings are attributed to: (i) the negative effect of soil salinity on water uptake, and the tradeoff between water uptake and drainage flux, and, concurrently, solute discharge below the root zone; and, (ii) the tradeoff between the effects of C and SAR on K(ψ) and θ(ψ). Furthermore, it was demonstrated that a data-driven protocol for soil salinity control, based on alternating irrigation water quality between TWW and desalinized water, guided by the soil solution salinity at the centroid of the soil volume active in water uptake, may lead to a substantial increase in crop yield, and to a substantial decrease in the salinity load in the groundwater.

  11. Salinity Gradient Energy from Expansion and Contraction of Poly(allylamine hydrochloride) Hydrogels.

    PubMed

    Bui, Tri Quang; Cao, Vinh Duy; Do, Nu Bich Duyen; Christoffersen, Trine Eker; Wang, Wei; Kjøniksen, Anna-Lena

    2018-06-22

    Salinity gradients exhibit a great potential for production of renewable energy. Several techniques such as pressure-retarded osmosis and reverse electrodialysis have been employed to extract this energy. Unfortunately, these techniques are restricted by the high costs of membranes and problems with membrane fouling. However, the expansion and contraction of hydrogels can be a new and cheaper way to harvest energy from salinity gradients since the hydrogels swell in freshwater and shrink in saltwater. We have examined the effect of cross-linker concentration and different external loads on the energy recovered for this type of energy-producing systems. Poly(allylamine hydrochloride) hydrogels were cross-linked with glutaraldehyde to produce hydrogels with excellent expansion and contraction properties. Increasing the cross-linker concentration markedly improved the energy that could be recovered from the hydrogels, especially at high external loads. A swollen hydrogel of 60 g could recover more than 1800 mJ when utilizing a high cross-linker concentration, and the maximum amount of energy produced per gram of polymer was 3.4 J/g. Although more energy is recovered at high cross-linking densities, the maximum amount of energy produced per gram of polymer is highest at an intermediate cross-linking concentration. Energy recovery was reduced when the salt concentration was increased for the low-concentration saline solution. The results illustrate that hydrogels are promising for salinity gradient energy recovery, and that optimizing the systems significantly increases the amount of energy that can be recovered.

  12. Mechanical Properties in a Bamboo Fiber/PBS Biodegradable Composite

    NASA Astrophysics Data System (ADS)

    Ogihara, Shinji; Okada, Akihisa; Kobayashi, Satoshi

    In recent years, biodegradable plastics which have low effect on environment have been developed. However, many of them have lower mechanical properties than conventional engineering plastics. Reinforcing them with a natural fiber is one of reinforcing methods without a loss of their biodegradability. In the present study, we use a bamboo fiber as the reinforcement and polybutylenesuccinate (PBS) as the matrix. We fabricate long fiber unidirectional composites and cross-ply laminate with different fiber weight fractions (10, 20, 30, 40 and 50wt%). We conduct tensile tests to evaluate the mechanical properties of these composites. In addition, we measure bamboo fiber strength distribution. We discuss the experimentally-obtained properties based on the mechanical properties of the constituent materials. Young's modulus and tensile strength in unidirectional composite and cross-ply laminate increase with increasing fiber weight fraction. However, the strain at fracture showed decreasing tendency. Young's modulus in fiber and fiber transverse directions are predictable by the rules of mixture. Tensile strength in fiber direction is lower than Curtin's prediction of strength which considers distribution of fiber strength. Young's modulus in cross-ply laminate is predictable by the laminate theory. However, analytical prediction of Poisson's ratio in cross-ply laminate by the laminate theory is lower than the experimental results.

  13. Colloidal PbS nanocrystals integrated to Si-based photonics for applications at telecom wavelengths

    NASA Astrophysics Data System (ADS)

    Humer, M.; Guider, R.; Jantsch, W.; Fromherz, T.

    2013-05-01

    In the last decade, Si based photonics has made major advances in terms of design, fabrication, and device implementation. But due to Silicon's indirect bandgap, it still remains a challenge to create efficient Si-based light emitting devices. In order to overcome this problem, an approach is to develop hybrid systems integrating light-emitting materials into Si. A promising class of materials for this purpose is the class of semiconducting nanocrystal quantum dots (NCs) that are synthesized by colloidal chemistry. As their absorption and emission wavelength depends on the dot size, which can easily be controlled during synthesis, they are extremely attractive as building blocks for nanophotonic applications. For applications in telecom wavelength, Lead chalcogenide colloidal NCs are optimum materials due to their unique optical, electronic and nonlinear properties. In this work, we experimentally demonstrate the integration of PbS nanocrystals into Si-based photonic structures like slot waveguides and ring resonators as optically pumped emitters for room temperature applications. In order to create such hybrid structures, the NCs were dissolved into polymer resists and drop cast on top of the device. Upon optical pumping, intense photoluminescence emission from the resonating modes is recorded at the output of the waveguide with transmission quality factors up to 14000. The polymer host material was investigated with respect to its ability to stabilize the NC's photoluminescence emission against degradation under ambient conditions. The waveguide-ring coupling efficiency was also investigated as function of the NCs concentrations blended into the polymer matrix. The integration of colloidal quantum dots into Silicon photonic structures as demonstrated in this work is a very versatile technique and thus opens a large range of applications utilizing the linear and nonlinear optical properties of PbS NCs at telecom wavelengths.

  14. Effects of salinity on establishment of Populus fremontii (cottonwood) and Tamarix ramosissima (saltcedar) in southwestern United States

    USGS Publications Warehouse

    Shafroth, Patrick B.; Friedman, Jonathan M.; Ischinger, Lee S.

    1995-01-01

    The exotic shrub Tamarix ramosissima (saltcedar) has replaced the native Populus fremontii(cottonwood) along many streams in southwestern United States. We used a controlled outdoor experiment to examine the influence of river salinity on germination and first year survival of P. fremontii var. wislizenii (Rio Grande cottonwood) and T. ramosissima on freshly deposited alluvial bars. We grew both species from seed in planters of sand subjected to a declining water table and solutions containing 0, 1, 3, and 5 times the concentrations of major ions in the Rio Grande at San Marcia, NM (1.2, 10.0, 25.7 and 37.4 meq 1-1; 0.11, 0.97, 2.37, and 3.45 dS m-1). Germination of P. fremontii declined by 35% with increasing salinity (P = .008). Germination of T. ramosissima was not affected. There were no significant effects of salinity on morality or above- and belowground growth of either species. In laboratory tests the same salinities had no effect onP. fremontii germination. P. fremontii germination is more sensitive to salinity outdoors than in covered petri dishes, probably because water scarcity resulting from eavaportion intensifies the low soil water potential associated with high salinity. River salinity appears to play only a minor role in determining relative numbers of P. fremontii and T. ramosissima seedlings on freshly deposited sandbars. However, over many years salt becomes concentrated on floodplains as a result of evaporation and salt extrusion from saltcedar leaves. T. ramosissima is known to be more tolerant of the resulting extreme salinities than P. fremontii. Therefore, increases in river salinities could indirectly contribute to decline of P. fremontii forests by exacerbating salt accumulation on floodplains.

  15. Electrochemical studies on zirconium and its biocompatible alloys Ti-50Zr at.% and Zr-2.5Nb wt.% in simulated physiologic media.

    PubMed

    Oliveira, Nilson T C; Biaggio, Sonia R; Rocha-Filho, Romeu C; Bocchi, Nerilso

    2005-09-01

    Different electrochemical studies were carried out for Zr and its biocompatible alloys Ti-50Zr at.% and Zr-2.5Nb wt.% in solutions simulating physiologic media, Ringer and PBS (phosphate buffered saline) solutions. The results from rest-potential measurements showed that the three materials are spontaneously passivated in both solutions and that the Ti-50Zr alloy has the greatest tendency for spontaneous oxide formation. Some corrosion parameters (such as the pitting and repassivation potentials) were obtained via cyclic voltammetry in both solutions, revealing that the Ti-50Zr has the best corrosion protection while Zr has the worst. On the other hand, the pre-anodization (up to 8 V vs. SCE) of the alloys in a 0.15 mol/L Na2SO4 solution led to a significant improvement in their protection against pitting corrosion when exposed to the Ringer solution. Elemental analyses by EDX showed that during pitting corrosion, there is no preferential corrosion of any of the alloying elements (Zr, Ti, Nb). Copyright (c) 2005 Wiley Periodicals, Inc.

  16. Effect of hypersaline cooling canals on aquifer salinization

    USGS Publications Warehouse

    Hughes, Joseph D.; Langevin, Christian D.; Brakefield-Goswami, Linzy

    2010-01-01

    The combined effect of salinity and temperature on density-driven convection was evaluated in this study for a large (28 km2) cooling canal system (CCS) at a thermoelectric power plant in south Florida, USA. A two-dimensional cross-section model was used to evaluate the effects of hydraulic heterogeneities, cooling canal salinity, heat transport, and cooling canal geometry on aquifer salinization and movement of the freshwater/saltwater interface. Four different hydraulic conductivity configurations, with values ranging over several orders of magnitude, were evaluated with the model. For all of the conditions evaluated, aquifer salinization was initiated by the formation of dense, hypersaline fingers that descended downward to the bottom of the 30-m thick aquifer. Saline fingers reached the aquifer bottom in times ranging from a few days to approximately 5 years for the lowest hydraulic conductivity case. Aquifer salinization continued after saline fingers reached the aquifer bottom and coalesced by lateral movement away from the site. Model results showed that aquifer salinization was most sensitive to aquifer heterogeneity, but was also sensitive to CCS salinity, temperature, and configuration.

  17. Microstrip Patch Sensor for Salinity Determination.

    PubMed

    Lee, Kibae; Hassan, Arshad; Lee, Chong Hyun; Bae, Jinho

    2017-12-18

    In this paper, a compact microstrip feed inset patch sensor is proposed for measuring the salinities in seawater. The working principle of the proposed sensor depends on the fact that different salinities in liquid have different relative permittivities and cause different resonance frequencies. The proposed sensor can obtain better sensitivity to salinity changes than common sensors using conductivity change, since the relative permittivity change to salinity is 2.5 times more sensitive than the conductivity change. The patch and ground plane of the proposed sensor are fabricated by conductive copper spray coating on the masks made by 3D printer. The fabricated patch and the ground plane are bonded to a commercial silicon substrate and then attached to 5 mm-high chamber made by 3D printer so that it contains only 1 mL seawater. For easy fabrication and testing, the maximum resonance frequency was selected under 3 GHz and to cover salinities in real seawater, it was assumed that the salinity changes from 20 to 35 ppt. The sensor was designed by the finite element method-based ANSYS high-frequency structure simulator (HFSS), and it can detect the salinity with 0.01 ppt resolution. The designed sensor has a resonance frequency separation of 37.9 kHz and reflection coefficients under -20 dB at the resonant frequencies. The fabricated sensor showed better performance with average frequency separation of 48 kHz and maximum reflection coefficient of -35 dB. By comparing with the existing sensors, the proposed compact and low-cost sensor showed a better detection capability. Therefore, the proposed patch sensor can be utilized in radio frequency (RF) tunable sensors for salinity determination.

  18. Response of Stream Biodiversity to Increasing Salinization

    NASA Astrophysics Data System (ADS)

    Hawkins, C. P.; Vander Laan, J. J.; Olson, J. R.

    2014-12-01

    We used a large data set of macroinvertebrate samples collected from streams in both reference-quality (n = 68) and degraded (n = 401) watersheds in the state of Nevada, USA to assess relationships between stream biodiversity and salinity. We used specific electrical conductance (EC)(μS/cm) as a measure of salinity, and applied a previously developed EC model to estimate natural, baseflow salinity at each stream. We used the difference between observed and predicted salinity (EC-Diff) as a measure of salinization associated with watershed degradation. Observed levels of EC varied between 22 and 994 μS/cm across reference sites and 22 to 3,256 uS/cm across non-reference sites. EC-Diff was as high as 2,743 μS/cm. We used a measure of local biodiversity completeness (ratio of observed to expected number of taxa) to assess ecological response to salinity. This O/E index decreased nearly linearly up to about 25% biodiversity loss, which occurred at EC-Diff of about 300 μS/cm. Too few sites had EC-Diff greater than 300 μS/cm to draw reliable inferences regarding biodiversity response to greater levels of salinization. EC-Diff increased with % agricultural land use, mine density, and % urban land use in the watersheds implying that human activities have been largely responsible for increased salinization in Nevada streams and rivers. Comparison of biological responses to EC and other stressors indicates that increased salinization may be the primary stressor causing biodiversity loss in these streams and that more stringent salinity water quality standards may be needed to protect aquatic life.

  19. Hurricane-induced failure of low salinity wetlands

    PubMed Central

    Howes, Nick C.; FitzGerald, Duncan M.; Hughes, Zoe J.; Georgiou, Ioannis Y.; Kulp, Mark A.; Miner, Michael D.; Smith, Jane M.; Barras, John A.

    2010-01-01

    During the 2005 hurricane season, the storm surge and wave field associated with Hurricanes Katrina and Rita eroded 527 km2 of wetlands within the Louisiana coastal plain. Low salinity wetlands were preferentially eroded, while higher salinity wetlands remained robust and largely unchanged. Here we highlight geotechnical differences between the soil profiles of high and low salinity regimes, which are controlled by vegetation and result in differential erosion. In low salinity wetlands, a weak zone (shear strength 500–1450 Pa) was observed ∼30 cm below the marsh surface, coinciding with the base of rooting. High salinity wetlands had no such zone (shear strengths > 4500 Pa) and contained deeper rooting. Storm waves during Hurricane Katrina produced shear stresses between 425–3600 Pa, sufficient to cause widespread erosion of the low salinity wetlands. Vegetation in low salinity marshes is subject to shallower rooting and is susceptible to erosion during large magnitude storms; these conditions may be exacerbated by low inorganic sediment content and high nutrient inputs. The dramatic difference in resiliency of fresh versus more saline marshes suggests that the introduction of freshwater to marshes as part of restoration efforts may therefore weaken existing wetlands rendering them vulnerable to hurricanes. PMID:20660777

  20. Aggregation and Particle Formation of Therapeutic Proteins in Contact With a Novel Fluoropolymer Surface Versus Siliconized Surfaces: Effects of Agitation in Vials and in Prefilled Syringes.

    PubMed

    Teska, Brandon M; Brake, Jeffrey M; Tronto, Gregory S; Carpenter, John F

    2016-07-01

    We examined the effects of an accelerated agitation protocol on 2 protein therapeutics, intravenous immunoglobulin (IVIG) and Avastin (bevacizumab), in contact with a novel fluoropolymer surface and more typical siliconized surfaces. The fluoropolymer surface provides "solid-phase" lubrication for the syringe plunger-obviating the need for silicone oil lubrication in prefilled syringes. We tested the 2 surfaces in a vial system and in prefilled glass syringes. We also examined the effects of 2 buffers, phosphate-buffered saline (PBS) and 0.2-M glycine, with and without the addition of polysorbate 20, on agitation-induced aggregation of IVIG. Aggregation was monitored by measuring subvisible particle formation and soluble protein loss. In both vials and syringes, protein particle formation was much lower during agitation with the fluoropolymer surface than with the siliconized surface. Also, particle formation was greater in PBS than in glycine buffer, an effect attributed to lower colloidal stability of IVIG in PBS. Polysorbate 20 in the formulation greatly inhibited protein particle formation. Overall, the fluoropolymer plunger surface in an unsiliconized glass barrel was demonstrated to be a viable solution for eliminating silicone oil droplets from prefilled syringe formulations and providing a consistent system for rationale formulation development and simplified particle analysis. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  1. Heparin Saline Versus Normal Saline for Flushing and Locking Peripheral Venous Catheters in Decompensated Liver Cirrhosis Patients

    PubMed Central

    Wang, Rui; Zhang, Ming-Guang; Luo, Ou; He, Liu; Li, Jia-Xin; Tang, Yun-Jing; Luo, Yan-Li; Zhou, Min; Tang, Li; Zhang, Zong-Xia; Wu, Hao; Chen, Xin-Zu

    2015-01-01

    Abstract A prospective randomized, controlled, single-blinded trial to compare the effectiveness and safety of heparin saline (HS) to those of normal saline (NS) as flushing and locking solutions for peripheral venous catheter (PVC) in decompensated liver cirrhosis (DLC) patients. Patients with DLC at our institution between April 2012 and March 2013 were enrolled after obtaining informed consent. The patients were randomly allocated into 2 groups: the NS group received preservative-free 0.9% sodium chloride as the flushing and locking solution, while the HS group received HS (50 U/mL). PVC-related events and the duration of PVC maintenance were compared between the 2 groups. Moreover, the preinfusion and postinfusion levels of prothrombin time (PT), activated partial thromboplastin time (APTT), and platelet (PLT) were also compared. A total of 32 and 36 DLC patients in the NS (125 PVCs) and HS (65 PVCs) groups, respectively, were analyzed. Baseline characteristics, including gender, age, Child–Pugh grade, PVC type and administration of anticoagulant, and irritant agents, were comparable between the 2 groups (P > 0.05). The maintenance times of the HS and NS groups were 80.27 ± 26.47 and 84.19 ± 29.32 hours, respectively (P = 0.397). Removal of PVC for abnormal reasons occurred in 30.7% and 22.4% of patients in the HS and NS groups (P = 0.208). The PVC occlusion rates were 6.2% and 5.6% in the HS and NS groups, respectively (OR = 1.11, 95% CI 0.31–3.92). The PT, APTT, and PLT levels were comparable between the 2 groups both before and after infusion (P > 0.05). Incremental analyses showed that Child–Pugh grade C might be a risk factor for the suppression of PLT in the HS group. We consider NS to be as effective as and safer than conventional HS for flushing and locking PVC in decompensated liver cirrhosis patients. PMID:26252305

  2. Serum Proteins Enhance Dispersion Stability and Influence the Cytotoxicity and Dosimetry of ZnO Nanoparticles in Suspension and Adherent Cancer Cell Models.

    PubMed

    Anders, Catherine B; Chess, Jordan J; Wingett, Denise G; Punnoose, Alex

    2015-12-01

    Agglomeration and sedimentation of nanoparticles (NPs) within biological solutions is a major limitation in their use in many downstream applications. It has been proposed that serum proteins associate with the NP surface to form a protein corona that limits agglomeration and sedimentation. Here, we investigate the effect of fetal bovine serum (FBS) proteins on the dispersion stability, dosimetry, and NP-induced cytotoxicity of cationic zinc oxide nanoparticles (nZnO) synthesized via forced hydrolysis with a core size of 10 nm. Two different in vitro cell culture models, suspension and adherent, were evaluated by comparing a phosphate buffered saline (PBS) nZnO dispersion (nZnO/PBS) and an FBS-stabilized PBS nZnO dispersion (nZnO - FBS/PBS). Surface interactions of FBS on nZnO were analyzed via spectroscopic and optical techniques. Fourier transformed infrared spectroscopy (FTIR) confirmed the adsorption of negatively charged protein components on the cationic nZnO surface through the disappearance of surfaced-adsorbed carboxyl functional groups and the subsequent detection of vibrational modes associated with the protein backbone of FBS-associated proteins. Further confirmation of these interactions was noted in the isoelectric point shift of the nZnO from the characteristic pH of 9.5 to a pH of 6.1. In nZnO - FBS/PBS dispersions, the FBS reduced agglomeration and sedimentation behaviors to impart long-term improvements (>24 h) to the nZnO dispersion stability. Furthermore, mathematical dosimetry models indicate that nZnO - FBS/PBS dispersions had consistent NP deposition patterns over time unlike unstable nZnO/PBS dispersions. In suspension cell models, the stable nZnO - FBS/PBS dispersion resulted in a ~33 % increase in the NP-induced cytotoxicity for both Jurkat leukemic and Hut-78 lymphoma cancer cells. In contrast, the nZnO - FBS/PBS dispersion resulted in 49 and 71 % reductions in the cytotoxicity observed towards the adherent breast (T-47D) and prostate

  3. Serum Proteins Enhance Dispersion Stability and Influence the Cytotoxicity and Dosimetry of ZnO Nanoparticles in Suspension and Adherent Cancer Cell Models

    NASA Astrophysics Data System (ADS)

    Anders, Catherine B.; Chess, Jordan J.; Wingett, Denise G.; Punnoose, Alex

    2015-11-01

    Agglomeration and sedimentation of nanoparticles (NPs) within biological solutions is a major limitation in their use in many downstream applications. It has been proposed that serum proteins associate with the NP surface to form a protein corona that limits agglomeration and sedimentation. Here, we investigate the effect of fetal bovine serum (FBS) proteins on the dispersion stability, dosimetry, and NP-induced cytotoxicity of cationic zinc oxide nanoparticles (nZnO) synthesized via forced hydrolysis with a core size of 10 nm. Two different in vitro cell culture models, suspension and adherent, were evaluated by comparing a phosphate buffered saline (PBS) nZnO dispersion (nZnO/PBS) and an FBS-stabilized PBS nZnO dispersion (nZnO - FBS/PBS). Surface interactions of FBS on nZnO were analyzed via spectroscopic and optical techniques. Fourier transformed infrared spectroscopy (FTIR) confirmed the adsorption of negatively charged protein components on the cationic nZnO surface through the disappearance of surfaced-adsorbed carboxyl functional groups and the subsequent detection of vibrational modes associated with the protein backbone of FBS-associated proteins. Further confirmation of these interactions was noted in the isoelectric point shift of the nZnO from the characteristic pH of 9.5 to a pH of 6.1. In nZnO - FBS/PBS dispersions, the FBS reduced agglomeration and sedimentation behaviors to impart long-term improvements (>24 h) to the nZnO dispersion stability. Furthermore, mathematical dosimetry models indicate that nZnO - FBS/PBS dispersions had consistent NP deposition patterns over time unlike unstable nZnO/PBS dispersions. In suspension cell models, the stable nZnO - FBS/PBS dispersion resulted in a ~33 % increase in the NP-induced cytotoxicity for both Jurkat leukemic and Hut-78 lymphoma cancer cells. In contrast, the nZnO - FBS/PBS dispersion resulted in 49 and 71 % reductions in the cytotoxicity observed towards the adherent breast (T-47D) and prostate

  4. Effects of salinity on baldcypress seedlings: responses and their relation to salinity tolerance physiological

    Treesearch

    James A. Allen; Jim L. Chambers; S. Reza Pezeshki

    1997-01-01

    Taxodium distichum var.distichum) subjected to flooding with saline water were evaluated in this study. Ten of the families were from coastal sites in Louisiana and Alabama, USA that have elevated levels of soil-water salinity. The other five families were from inland, freshwater sites in Louisiana. Seedlings from all families...

  5. Transcriptome Exploration in Leymus chinensis under Saline-Alkaline Treatment Using 454 Pyrosequencing

    PubMed Central

    Sun, Yepeng; Wang, Fawei; Wang, Nan; Dong, Yuanyuan; Liu, Qi; Zhao, Lei; Chen, Huan; Liu, Weican; Yin, Hailong; Zhang, Xiaomei; Yuan, Yanxi; Li, Haiyan

    2013-01-01

    Background Leymus chinensis (Trin.) Tzvel. is a high saline-alkaline tolerant forage grass genus of the tribe Gramineae family, which also plays an important role in protection of natural environment. To date, little is known about the saline-alkaline tolerance of L. chinensis on the molecular level. To better understand the molecular mechanism of saline-alkaline tolerance in L. chinensis, 454 pyrosequencing was used for the transcriptome study. Results We used Roche-454 massive parallel pyrosequencing technology to sequence two different cDNA libraries that were built from the two samples of control and under saline-alkaline treatment (optimal stress concentration-Hoagland solution with 100 mM NaCl and 200 mM NaHCO3). A total of 363,734 reads in control group and 526,267 reads in treatment group with an average length of 489 bp and 493 bp were obtained, respectively. The reads were assembled into 104,105 unigenes with MIRA sequence assemable software, among which, 73,665 unigenes were in control group, 88,016 unigenes in treatment group and 57,576 unigenes in both groups. According to the comparative expression analysis between the two groups with the threshold of “log2 Ratio ≥1”, there were 36,497 up-regulated unegenes and 18,218 down-regulated unigenes predicted to be the differentially expressed genes. After gene annotation and pathway enrichment analysis, most of them were involved in stress and tolerant function, signal transduction, energy production and conversion, and inorganic ion transport. Furthermore, 16 of these differentially expressed genes were selected for real-time PCR validation, and they were successfully confirmed with the results of 454 pyrosequencing. Conclusions This work is the first time to study the transcriptome of L. chinensis under saline-alkaline treatment based on the 454-FLX massively parallel DNA sequencing platform. It also deepened studies on molecular mechanisms of saline-alkaline in L. chinensis, and constituted a

  6. The origin and mechanisms of salinization of the Lower Jordan River

    USGS Publications Warehouse

    Farber, E.; Vengosh, A.; Gavrieli, I.; Marie, Amarisa; Bullen, T.D.; Mayer, B.; Holtzman, R.; Segal, M.; Shavit, U.

    2004-01-01

    The chemical and isotopic (87Sr/86Sr, ??11B, ??34Ssulfate, ??18Owater, ??15Nnitrate) compositions of water from the Lower Jordan River and its major tributaries between the Sea of Galilee and the Dead Sea were determined in order to reveal the origin of the salinity of the Jordan River. We identified three separate hydrological zones along the flow of the river: (1) A northern section (20 km downstream of its source) where the base flow composed of diverted saline and wastewaters is modified due to discharge of shallow sulfate-rich groundwater, characterized by low 87Sr/86Sr (0.7072), ??34Ssulfate (-2???), high ??11B (???36???), ??15Nnitrate (???15???) and high ??18Owater (-2 to-3???) values. The shallow groundwater is derived from agricultural drainage water mixed with natural saline groundwater and discharges to both the Jordan and Yarmouk rivers. The contribution of the groundwater component in the Jordan River flow, deduced from mixing relationships of solutes and strontium isotopes, varies from 20 to 50% of the total flow. (2) A central zone (20-50 km downstream from its source) where salt variations are minimal and the rise of 87Sr/86Sr and SO4/Cl ratios reflects predominance of eastern surface water flows. (3) A southern section (50-100 km downstream of its source) where the total dissolved solids of the Jordan River increase, particularly during the spring (70-80 km) and summer (80-100 km) to values as high as 11.1 g/L. Variations in the chemical and isotopic compositions of river water along the southern section suggest that the Zarqa River (87Sr/86Sr???0.70865; ??11B???25???) has a negligible affect on the Jordan River. Instead, the river quality is influenced primarily by groundwater discharge composed of sulfate-rich saline groundwater (Cl-=31-180 mM; SO4/Cl???0.2-0.5; Br/Cl???2-3??10-3; 87Sr/86Sr???0.70805; ??11B???30???; ??15Nnitrate ???17???, ??34Ssulfate=4-10???), and Ca-chloride Rift valley brines (Cl-=846-1500 mM; Br/Cl???6-8??10-3; 87Sr/86Sr???0

  7. Does salinity change determine zooplankton variability in the saline Qarun Lake (Egypt)?

    NASA Astrophysics Data System (ADS)

    El-Shabrawy, Gamal M.; Anufriieva, Elena V.; Germoush, Mousa O.; Goher, Mohamed E.; Shadrin, Nickolai V.

    2015-11-01

    Zooplankton and 14 abiotic variables were studied during August 2011 at 10 stations in Lake Qarun, Egypt. Stations with the lowest salinity and highest nutrient concentrations and turbidity were close to the discharge of waters from the El-Bats and El-Wadi drainage systems. A total of 15 holozooplankton species were identified. The salinity in Lake Qarun increased and fluctuated since 1901: 12 g/L in 1901; 8.5 g/L in 1905; 12.0 g/L in 1922; 30.0 g/L in 1985; 38.7 g/L in 1994; 35.3 g/L in 2006, and 33.4 g/L in 2011. The mean concentration of nutrients (nitrate, nitrite and orthophosphate) gradually increased from 35, 0.16 and 0.38 µg/L, respectively, in 1953-1955 to 113, 16.4, and 30.26 µg/L in 2011. From 1999-2003 some decrease of species diversity occurred. Average total zooplankton density was 30 000 ind./m3 in 1974-1977; 356 125 ind./m3 in 1989; 534 000 ind./m3 in 1994-1995; from 965 000 to 1 452 000 ind./m3 in 2006, and 595 000 ind./m3 in 2011. A range of long-term summer salinity variability during the last decades was very similar to a range of salinity spatial variability in summer 2011. There is no significant correlation between zooplankton abundance and salinity in spatial and long-term changes. We conclude that salinity fluctuations since at least 1955 did not directly drive the changes of composition and abundance of zooplankton in the lake. A marine community had formed in the lake, and it continues to change. One of the main drivers of this change is a regular introduction and a pressure of alien species on the existent community. Eutrophication also plays an important role. The introduction of Mnemiopsis leidyi, first reported in 2014, may lead to a start of a new stage of the biotic changes in Lake Qarun, when eutrophication and the population dynamics of this ctenophore will be main drivers of the ecosystem change.

  8. Response to non-uniform salinity in the root zone of the halophyte Atriplex nummularia: growth, photosynthesis, water relations and tissue ion concentrations.

    PubMed

    Bazihizina, Nadia; Colmer, Timothy D; Barrett-Lennard, Edward G

    2009-09-01

    Soil salinity is often heterogeneous, yet the physiology of halophytes has typically been studied with uniform salinity treatments. An evaluation was made of the growth, net photosynthesis, water use, water relations and tissue ions in the halophytic shrub Atriplex nummularia in response to non-uniform NaCl concentrations in a split-root system. Atriplex nummularia was grown in a split-root system for 21 d, with either the same or two different NaCl concentrations (ranging from 10 to 670 mm), in aerated nutrient solution bathing each root half. Non-uniform salinity, with high NaCl in one root half (up to 670 mm) and 10 mm in the other half, had no effect on shoot ethanol-insoluble dry mass, net photosynthesis or shoot pre-dawn water potential. In contrast, a modest effect occurred for leaf osmotic potential (up to 30 % more solutes compared with uniform 10 mm NaCl treatment). With non-uniform NaCl concentrations (10/670 mm), 90 % of water was absorbed from the low salinity side, and the reduction in water use from the high salinity side caused whole-plant water use to decrease by about 30 %; there was no compensatory water uptake from the low salinity side. Leaf Na(+) and Cl(-) concentrations were 1.9- to 2.3-fold higher in the uniform 670 mm treatment than in the 10/670 mm treatment, whereas leaf K(+) concentrations were 1.2- to 2.0-fold higher in the non-uniform treatment. Atriplex nummularia with one root half in 10 mm NaCl maintained net photosynthesis, shoot growth and shoot water potential even when the other root half was exposed to 670 mm NaCl, a concentration that inhibits growth by 65 % when uniform in the root zone. Given the likelihood of non-uniform salinity in many field situations, this situation would presumably benefit halophyte growth and physiology in saline environments.

  9. Response to non-uniform salinity in the root zone of the halophyte Atriplex nummularia: growth, photosynthesis, water relations and tissue ion concentrations

    PubMed Central

    Bazihizina, Nadia; Colmer, Timothy D.; Barrett-Lennard, Edward G.

    2009-01-01

    Background and Aims Soil salinity is often heterogeneous, yet the physiology of halophytes has typically been studied with uniform salinity treatments. An evaluation was made of the growth, net photosynthesis, water use, water relations and tissue ions in the halophytic shrub Atriplex nummularia in response to non-uniform NaCl concentrations in a split-root system. Methods Atriplex nummularia was grown in a split-root system for 21 d, with either the same or two different NaCl concentrations (ranging from 10 to 670 mm), in aerated nutrient solution bathing each root half. Key Results Non-uniform salinity, with high NaCl in one root half (up to 670 mm) and 10 mm in the other half, had no effect on shoot ethanol-insoluble dry mass, net photosynthesis or shoot pre-dawn water potential. In contrast, a modest effect occurred for leaf osmotic potential (up to 30 % more solutes compared with uniform 10 mm NaCl treatment). With non-uniform NaCl concentrations (10/670 mm), 90 % of water was absorbed from the low salinity side, and the reduction in water use from the high salinity side caused whole-plant water use to decrease by about 30 %; there was no compensatory water uptake from the low salinity side. Leaf Na+ and Cl− concentrations were 1·9- to 2·3-fold higher in the uniform 670 mm treatment than in the 10/670 mm treatment, whereas leaf K+ concentrations were 1·2- to 2·0-fold higher in the non-uniform treatment. Conclusions Atriplex nummularia with one root half in 10 mm NaCl maintained net photosynthesis, shoot growth and shoot water potential even when the other root half was exposed to 670 mm NaCl, a concentration that inhibits growth by 65 % when uniform in the root zone. Given the likelihood of non-uniform salinity in many field situations, this situation would presumably benefit halophyte growth and physiology in saline environments. PMID:19556265

  10. Estuarine turbidity, flushing, salinity, and circulation

    NASA Technical Reports Server (NTRS)

    Pritchard, D. W.

    1972-01-01

    The effects of estuarine turbidity, flushing, salinity, and circulation on the ecology of the Chesapeake Bay are discussed. The sources of fresh water, the variations in salinity, and the circulation patterns created by temperature and salinity changes are analyzed. The application of remote sensors for long term observation of water temperatures is described. The sources of sediment and the biological effects resulting from increased sediments and siltation are identified.

  11. A study of lateral fall-off (penumbra) optimisation for pencil beam scanning (PBS) proton therapy

    NASA Astrophysics Data System (ADS)

    Winterhalter, C.; Lomax, A.; Oxley, D.; Weber, D. C.; Safai, S.

    2018-01-01

    The lateral fall-off is crucial for sparing organs at risk in proton therapy. It is therefore of high importance to minimize the penumbra for pencil beam scanning (PBS). Three optimisation approaches are investigated: edge-collimated uniformly weighted spots (collimation), pencil beam optimisation of uncollimated pencil beams (edge-enhancement) and the optimisation of edge collimated pencil beams (collimated edge-enhancement). To deliver energies below 70 MeV, these strategies are evaluated in combination with the following pre-absorber methods: field specific fixed thickness pre-absorption (fixed), range specific, fixed thickness pre-absorption (automatic) and range specific, variable thickness pre-absorption (variable). All techniques are evaluated by Monte Carlo simulated square fields in a water tank. For a typical air gap of 10 cm, without pre-absorber collimation reduces the penumbra only for water equivalent ranges between 4-11 cm by up to 2.2 mm. The sharpest lateral fall-off is achieved through collimated edge-enhancement, which lowers the penumbra down to 2.8 mm. When using a pre-absorber, the sharpest fall-offs are obtained when combining collimated edge-enhancement with a variable pre-absorber. For edge-enhancement and large air gaps, it is crucial to minimize the amount of material in the beam. For small air gaps however, the superior phase space of higher energetic beams can be employed when more material is used. In conclusion, collimated edge-enhancement combined with the variable pre-absorber is the recommended setting to minimize the lateral penumbra for PBS. Without collimator, it would be favourable to use a variable pre-absorber for large air gaps and an automatic pre-absorber for small air gaps.

  12. Low temperature regulated growth of PbS quantum dots by wet chemical method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kumar, Hitanshu, E-mail: hitanshuminhas@gmail.com; Barman, P. B.; Singh, Ragini Raj

    2015-08-28

    Narrow size distribution with regulated synthesis of lead sulfide (PbS) quantum dots (QDs) was achieved through wet chemical method. Different concentrations of 2-mercaptoethanol (capping agent) were used for tailoring the QDs size. Transmission electron microscopy and X-ray diffraction studies revealed that the QDs have mean diameters between 6 to 15 nm. The optical absorption spectra were compared to the predictions of a theoretical model for the electronic structure. The theory agrees well with experiment for QDs larger than 7 nm, but for smaller dots there is some deviation from the theoretical predictions. Consequently, the produced particles are having monodispersity, good water solubility,more » stability and may be good arguments to be biologically compatible due to the use of 2-mercaptoethanol.« less

  13. Salinity and turbidity distributions in the Brisbane River estuary, Australia

    NASA Astrophysics Data System (ADS)

    Yu, Yingying; Zhang, Hong; Lemckert, Charles

    2014-11-01

    The Brisbane River estuary (BRE) in Australia not only plays a vital role in ecosystem health, but is also of importance for people who live nearby. Comprehensive investigations, both in the short- and long-term, into the salinity and turbidity distributions in the BRE were conducted. Firstly, the analysis of numerical results revealed that the longitudinal salinity varied at approximately 0.45 and 0.61 psu/h during neap and spring tides, respectively. The turbidity stayed at a higher level and was less impacted by tide in the upper estuary, however, the water cleared up while the tide changed from flood to ebb in the mid and lower estuary. The second investigation into the seasonal variations of salinity and turbidity in the BRE was conducted, using ten-year field measurement data. A fourth-order polynomial equation was proposed, describing the longitudinal variation in salinity dilution changes as the upstream distance in the BRE during the wet and dry seasons. From the observation, the mid and upper estuaries were vertically well-mixed during both seasons, but the lower BRE was stratified, particularly during the wet season. The estuary turbidity maximum (ETM) zone was about 10 km longer during the wet season than the dry season. Particular emphasis was given to the third investigation into the use of satellite remote sensing techniques for estimation of the turbidity level in the BRE. A linear relationship between satellite observed water reflectance and surface turbidity level in the BRE was validated with an R2 of 0.75. The application of satellite-observed water reflectance therefore provided a practical solution for estimating surface turbidity levels of estuarine rivers not only under normal weather conditions, but also during flood events. The results acquired from this study are valuable for further hydrological research in the BRE and particularly prominent for immediate assessment of flood impacts.

  14. Balanced versus chloride-rich solutions for fluid resuscitation in brain-injured patients: a randomised double-blind pilot study

    PubMed Central

    2013-01-01

    Introduction We sought to investigate whether the use of balanced solutions reduces the incidence of hyperchloraemic acidosis without increasing the risk for intracranial hypertension in patients with severe brain injury. Methods We conducted a single-centre, two-arm, randomised, double-blind, pilot controlled trial in Nantes, France. Patients with severe traumatic brain injury (Glasgow Coma Scale score ≤8) or subarachnoid haemorrhage (World Federation of Neurosurgical Society grade III or higher) who were mechanically ventilated were randomised within the first 12 hours after brain injury to receive either isotonic balanced solutions (crystalloid and hydroxyethyl starch; balanced group) or isotonic sodium chloride solutions (crystalloid and hydroxyethyl starch; saline group) for 48 hours. The primary endpoint was the occurrence of hyperchloraemic metabolic acidosis within 48 hours. Results Forty-two patients were included, of whom one patient in each group was excluded (one consent withdrawn and one use of forbidden therapy). Nineteen patients (95%) in the saline group and thirteen (65%) in the balanced group presented with hyperchloraemic acidosis within the first 48 hours (hazard ratio = 0.28, 95% confidence interval [CI] = 0.11 to 0.70; P = 0.006). In the saline group, pH (P = .004) and strong ion deficit (P = 0.047) were lower and chloraemia was higher (P = 0.002) than in the balanced group. Intracranial pressure was not different between the study groups (mean difference 4 mmHg [-1;8]; P = 0.088). Seven patients (35%) in the saline group and eight (40%) in the balanced group developed intracranial hypertension (P = 0.744). Three patients (14%) in the saline group and five (25%) in the balanced group died (P = 0.387). Conclusions This study provides evidence that balanced solutions reduce the incidence of hyperchloraemic acidosis in brain-injured patients compared to saline solutions. Even if the study was not powered sufficiently for this endpoint

  15. Saline Systems highlights for 2005

    PubMed Central

    2006-01-01

    On the 4th of July, 2005, the Saline Systems editorial group launched the new online open access journal, Saline Systems, with BioMed Central as the publisher. The scope of the journal includes both basic and applied research on halophilic organisms and saline environments, from gene systems to ecosystems. The stated goal of the journal is to meet publication needs for researchers working in coastal and inland saline environments and provide an interdisciplinary and readily accessible forum for scientists worldwide. The inaugural volume of the journal contains a significant number of high quality original research papers and reviews on a wide range of relevant topics. At the end of the launch period, from January 1, 2006 onwards, the journal will be introducing article-processing charges to cover the cost of publication. Charges will be partly or completely waived for authors from BioMed Central institutional subscribers and in cases of financial hardship. PMID:16417635

  16. A global perspective on wetland salinization: ecological consequences of a growing threat to freshwater wetlands

    DOE PAGES

    Herbert, Ellen R.; Boon, Paul; Burgin, Amy J.; ...

    2015-10-29

    Salinization, a widespread threat to the structure and ecological functioning of inland and coastal wetlands, is currently occurring at an unprecedented rate and geographic scale. The causes of salinization are diverse and include alterations to freshwater flows, land-clearance, irrigation, disposal of wastewater effluent, sea level rise, storm surges, and applications of de-icing salts. Climate change and anthropogenic modifications to the hydrologic cycle are expected to further increase the extent and severity of wetland salinization. Salinization alters the fundamental physicochemical nature of the soil-water environment, increasing ionic concentrations and altering chemical equilibria and mineral solubility. Increased concentrations of solutes, especially sulfate,more » alter the biogeochemical cycling of major elements including carbon, nitrogen, phosphorus, sulfur, iron, and silica. The effects of salinization on wetland biogeochemistry typically include decreased inorganic nitrogen removal (with implications for water quality and climate regulation), decreased carbon storage (with implications for climate regulation and wetland accretion), and increased generation of toxic sulfides (with implications for nutrient cycling and the health/functioning of wetland biota). Indeed, increased salt and sulfide concentrations induce physiological stress in wetland biota and ultimately can result in large shifts in wetland communities and their associated ecosystem functions. The productivity and composition of freshwater species assemblages will be highly altered, and there is a high potential for the disruption of existing interspecific interactions. Although there is a wealth of information on how salinization impacts individual ecosystem components, relatively few studies have addressed the complex and often non-linear feedbacks that determine ecosystem-scale responses or considered how wetland salinization will affect landscape-level processes. Although the

  17. A global perspective on wetland salinization: ecological consequences of a growing threat to freshwater wetlands

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Herbert, Ellen R.; Boon, Paul; Burgin, Amy J.

    Salinization, a widespread threat to the structure and ecological functioning of inland and coastal wetlands, is currently occurring at an unprecedented rate and geographic scale. The causes of salinization are diverse and include alterations to freshwater flows, land-clearance, irrigation, disposal of wastewater effluent, sea level rise, storm surges, and applications of de-icing salts. Climate change and anthropogenic modifications to the hydrologic cycle are expected to further increase the extent and severity of wetland salinization. Salinization alters the fundamental physicochemical nature of the soil-water environment, increasing ionic concentrations and altering chemical equilibria and mineral solubility. Increased concentrations of solutes, especially sulfate,more » alter the biogeochemical cycling of major elements including carbon, nitrogen, phosphorus, sulfur, iron, and silica. The effects of salinization on wetland biogeochemistry typically include decreased inorganic nitrogen removal (with implications for water quality and climate regulation), decreased carbon storage (with implications for climate regulation and wetland accretion), and increased generation of toxic sulfides (with implications for nutrient cycling and the health/functioning of wetland biota). Indeed, increased salt and sulfide concentrations induce physiological stress in wetland biota and ultimately can result in large shifts in wetland communities and their associated ecosystem functions. The productivity and composition of freshwater species assemblages will be highly altered, and there is a high potential for the disruption of existing interspecific interactions. Although there is a wealth of information on how salinization impacts individual ecosystem components, relatively few studies have addressed the complex and often non-linear feedbacks that determine ecosystem-scale responses or considered how wetland salinization will affect landscape-level processes. Although the

  18. Pulp tissue dissolution capacity of QMix 2in1 irrigation solution.

    PubMed

    Arslan, Dilara; Guneser, Mehmet Burak; Kustarci, Alper; Er, Kursat; Siso, Seyda Herguner

    2015-01-01

    The aim of this study was to evaluate the tissue dissolution efficacy of four root canal irrigation solutions (sodium hypochlorite [NaOCl], chlorhexidine gluconate [CHX], Octenidine [OCT], and QMix 2in1) on bovine pulp tissue. Fifty bovine pulp tissue samples, each weighing 6.55 mg, were prepared and randomly divided into four experimental groups and one control group (n = 10) according to the dissolution irrigants used: (1) 5.25% NaOCl group; (2) 2% CHX group; (3) OCT group; (4) QMix 2in1 group; and (5) control group (saline solution). These samples were then placed into special bovine dentin reservoir models and immersed for 1 h with each test solution (0.1 mL of each) at room temperature. The pulp samples were then blotted dry and weighed again. The percentage of weight loss was calculated. Statistically analyzed with one-way analysis of variance and post-hoc Tukey tests (P = 0.05). Saline solution did not dissolve the bovine pulp tissue. All groups, except OCT, dissolved pulp samples more effectively than the control group (P < 0.05). The highest tissue dissolution was observed in 5.25% NaOCl group (P < 0.05). No statistically significant difference was found between the tissue-dissolving effect between QMix 2in1 and those of 2% CHX. Within the limitations of this in vitro study, NaOCl exhibited the best tissue-dissolving effect out of all solutions tested. CHX and QMix 2in1 were able to dissolve pulp tissue but less than NaOCl. OCT and saline solutions could not exhibit significantly tissue-dissolving effectiveness. This study shown that QMix 2in1 has little capacity to dissolve pulp tissue therefore used alone is not sufficient for this purpose.

  19. Pulp tissue dissolution capacity of QMix 2in1 irrigation solution

    PubMed Central

    Arslan, Dilara; Guneser, Mehmet Burak; Kustarci, Alper; Er, Kursat; Siso, Seyda Herguner

    2015-01-01

    Objective: The aim of this study was to evaluate the tissue dissolution efficacy of four root canal irrigation solutions (sodium hypochlorite [NaOCl], chlorhexidine gluconate [CHX], Octenidine [OCT], and QMix 2in1) on bovine pulp tissue. Materials and Methods: Fifty bovine pulp tissue samples, each weighing 6.55 mg, were prepared and randomly divided into four experimental groups and one control group (n = 10) according to the dissolution irrigants used: (1) 5.25% NaOCl group; (2) 2% CHX group; (3) OCT group; (4) QMix 2in1 group; and (5) control group (saline solution). These samples were then placed into special bovine dentin reservoir models and immersed for 1 h with each test solution (0.1 mL of each) at room temperature. The pulp samples were then blotted dry and weighed again. The percentage of weight loss was calculated. Statistically analyzed with one-way analysis of variance and post-hoc Tukey tests (P = 0.05). Results: Saline solution did not dissolve the bovine pulp tissue. All groups, except OCT, dissolved pulp samples more effectively than the control group (P < 0.05). The highest tissue dissolution was observed in 5.25% NaOCl group (P < 0.05). No statistically significant difference was found between the tissue-dissolving effect between QMix 2in1 and those of 2% CHX. Conclusions: Within the limitations of this in vitro study, NaOCl exhibited the best tissue-dissolving effect out of all solutions tested. CHX and QMix 2in1 were able to dissolve pulp tissue but less than NaOCl. OCT and saline solutions could not exhibit significantly tissue-dissolving effectiveness. This study shown that QMix 2in1 has little capacity to dissolve pulp tissue therefore used alone is not sufficient for this purpose. PMID:26430374

  20. Physiological and leaf metabolome changes in the xerohalophyte species Atriplex halimus induced by salinity.

    PubMed

    Bendaly, Alia; Messedi, Dorsaf; Smaoui, Abderrazak; Ksouri, Riadh; Bouchereau, Alain; Abdelly, Chedly

    2016-06-01

    Atriplex halimus is a xerohalophyte plant, which could be used as cash crops. This plant was integrated in Tunisian government programs the aim of which is to rehabilitate saline areas and desert. To investigate its strategies involved in salt tolerance, A. halimus was grown hydroponically under controlled conditions with increasing salinity. Plants were harvested and analyzed after 60 days of treatment. The biomass of A. halimus increased by moderate salinity and decreased significantly at high salinity compared to control plants at 400 mM. Despite of the large amounts of Na(+) observed in the leaves of Atriplex plants, leaf water contents and leaf succulence kept on increasing in treated plants and decreased over 150 mM NaCl. This confirmed the compartmentation and the efficient contribution of Na(+) in the osmotic adjustment. Analysis of the metabolic profiles showed an accumulation of carbohydrates and amino acids. The leaf tissues preferentially stored proline, α alanine and sucrose. Increasing NaCl levels were also accompanied by a significant accumulation of malate in leaves. Involvement of these solutes in osmotic adjustment was considered low. Nevertheless, they seemed to have an important role in controlling photosynthesis which capacity was enhanced by low salinity and decreased with increasing salinity (evaluated by actual photochemical efficiency of photosystem II and chlorophyll contents). The unchanged maximum photochemical efficiency of photosystem II accompanied by the increase of the non-photochemical quenching, the enhancement of the total antioxidant activity and the decrease of the malondialdehyde contents in leaves showed efficient protection of membranes and photosystem II from photo-oxidative damage. This protection seemed to be attributed to proline and sucrose largely accumulated in leaves treated with salt. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  1. Salinity: Electrical conductivity and total dissolved solids

    USDA-ARS?s Scientific Manuscript database

    The measurement of soil salinity is a quantification of the total salts present in the liquid portion of the soil. Soil salinity is important in agriculture because salinity reduces crop yields by reducing the osmotic potential making it more difficult for the plant to extract water, by causing spe...

  2. On the evolution of the adaptation of Lophopyrum elongatum to growth in saline environments

    PubMed Central

    Dvořák, Jan; Edge, Mark; Ross, Kathleen

    1988-01-01

    Most species of the genus Lophopyrum Löve (Agropyron Geartn.) grow in saline environments and are more tolerant of saline stress than the species of the related genus Triticum L. A 56-chromosome amphiploid from the cross Triticum aestivum cv. Chinese Spring × Lophopyrum elongatum exceeded Chinese Spring in salt tolerance, measured as plant dry-matter production and seed yield in solution cultures with 250 mM NaCl. Thus, the adaptation of Lophopyrum to saline environments is expressed in the wheat genetic background. None of the disomic additions or substitutions of L. elongatum chromosomes in Chinese Spring showed a similar level of saline stress tolerance, which indicates that the trait depends on the activity of genes on more than one chromosome. Comparisons of disomic additions, double monosomic additions from half-diallel crosses among disomic additions, and disomic substitutions of L. elongatum chromosomes in Chinese Spring with Chinese Spring indicated that the enhanced salt tolerance of the amphiploid is primarily controlled by genes with minor effects on three of the seven chromosomes, 3E, 4E, and 7E, interacting in a largely additive manner. The salt tolerance of L. elongatum additionally depends on several minor nonadditive gene interactions. It is concluded that the adaptation of L. elongatum to growth in saline environments evolved by accumulation of new alleles in a number of loci, each with a relatively small effect on salt tolerance. It is further inferred that most of these new alleles were codominant to the original alleles and were able to act independently in enhancing salt tolerance. PMID:16593932

  3. Electrospun PVA/Bentonite Nanocomposites Mats for Drug Delivery

    PubMed Central

    Ferrández-Rives, Mariola; Gómez Ribelles, José Luis

    2017-01-01

    Electrospun mats and films of polyvinyl alcohol (PVA) hydrogel are produced for drug delivery. To provide mechanical consistency to the gel a reinforcement by nanoclays is introduced in the polymer matrix. Four different suspensions of nanoparticles in the polymer solution are prepared in an adequate solvent. These suspensions are subjected to an electrospinning process to produce the nanofiber mat, while films are produced by casting. The influence of the process parameters over the nanofibers microstructure is analyzed by scanning electron microscopy (SEM). The effectiveness of nanoclay encapsulation in the nanocomposites is tested by a thermogravimetric analysis. A crosslinking reaction in solution is carried out to prevent the dissolution of the nanocomposites in aqueous media. A model protein (bovine serum albumin, BSA) is absorbed in the nanocomposites to characterize the release kinetics in phosphate-buffered saline (PBS). PMID:29261123

  4. Influence of silica nanospheres on corrosion behavior of magnesium matrix syntactic foam

    NASA Astrophysics Data System (ADS)

    Qureshi, W.; Kannan, S.; Vincent, S.; Eddine, N. N.; Muhammed, A.; Gupta, M.; Karthikeyan, R.; Badari, V.

    2018-04-01

    Over the years, the development of Magnesium alloys as biodegradable implants has seen significant advancements. Magnesium based materials tend to provide numerous advantages in the field of biomedical implants over existing materials such as titanium or stainless steel. The present research focuses on corrosive behavior of Magnesium reinforced with different volume percentages of Hollow Silica Nano Spheres (HSNS). These behaviors were tested in two different simulated body fluids (SBF) namely, Hank’s Buffered Saline Solution (HBSS) and Phosphate Buffered Solution (PBS). This corrosion study was done using the method of electrochemical polarization with a three-electrode configuration. Comparative studies were established by testing pure Mg which provided critical information on the effects of the reinforcing material. The HSNS reinforced Mg displayed desirable characteristics after corrosion experiments; increased corrosion resistance was witnessed with higher volume percentage of HSNS.

  5. Continuous salinity and temperature data from san francisco estuary, 19822002: Trends and the salinity-freshwater inflow relationship

    USGS Publications Warehouse

    Shellenbarger, G.G.; Schoellhamer, D.H.

    2011-01-01

    The U.S. Geological Survey and other federal and state agencies have been collecting continuous temperature and salinity data, two critical estuarine habitat variables, throughout San Francisco estuary for over two decades. Although this dynamic, highly variable system has been well studied, many questions remain relating to the effects of freshwater inflow and other physical and biological linkages. This study examines up to 20 years of publically available, continuous temperature and salinity data from 10 different San Francisco Bay stations to identify trends in temperature and salinity and quantify the salinityfreshwater inflow relationship. Several trends in the salinity and temperature records were identified, although the high degree of daily and interannual variability confounds the analysis. In addition, freshwater inflow to the estuary has a range of effects on salinity from -0.0020 to -0.0096 (m3 s-1) -1 discharge, depending on location in the estuary and the timescale of analyzed data. Finally, we documented that changes in freshwater inflow to the estuary that are within the range of typical management actions can affect bay-wide salinities by 0.61.4. This study reinforces the idea that multidecadal records are needed to identify trends from decadal changes in water management and climate and, therefore, are extremely valuable. ?? 2011 Coastal Education & Research Foundation.

  6. The U.S. Salinity Laboratory (USDA-ARS) guidelines for assessing multi-scale soil salinity with proximal and remote sensing

    USDA-ARS?s Scientific Manuscript database

    Soil salinity is a major threat to sustainable agriculture, especially in arid and semi-arid regions. Updated and accurate inventories of salinity in agronomically and environmentally relevant ranges (i.e., <20 dS/m, when salinity is measured as electrical conductivity of the saturation extract, ECe...

  7. Soil salinity decreases global soil organic carbon stocks.

    PubMed

    Setia, Raj; Gottschalk, Pia; Smith, Pete; Marschner, Petra; Baldock, Jeff; Setia, Deepika; Smith, Jo

    2013-11-01

    Saline soils cover 3.1% (397 million hectare) of the total land area of the world. The stock of soil organic carbon (SOC) reflects the balance between carbon (C) inputs from plants, and losses through decomposition, leaching and erosion. Soil salinity decreases plant productivity and hence C inputs to the soil, but also microbial activity and therefore SOC decomposition rates. Using a modified Rothamsted Carbon model (RothC) with a newly introduced salinity decomposition rate modifier and a plant input modifier we estimate that, historically, world soils that are currently saline have lost an average of 3.47 tSOC ha(-1) since they became saline. With the extent of saline soils predicted to increase in the future, our modelling suggests that world soils may lose 6.8 Pg SOC due to salinity by the year 2100. Our findings suggest that current models overestimate future global SOC stocks and underestimate net CO2 emissions from the soil-plant system by not taking salinity effects into account. From the perspective of enhancing soil C stocks, however, given the lower SOC decomposition rate in saline soils, salt tolerant plants could be used to sequester C in salt-affected areas. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Sources of salinity and boron in the Gaza strip: Natural contaminant flow in the southern Mediterranean coastal aquifer

    NASA Astrophysics Data System (ADS)

    Vengosh, Avner; Kloppmann, Wolfram; Marei, Amer; Livshitz, Yakov; Gutierrez, Alexis; Banna, Mazen; Guerrot, Catherine; Pankratov, Irena; Raanan, Hadas

    2005-01-01

    Salinization in coastal aquifers is a global phenomenon resulting from the overexploitation of scarce water resources. The Gaza Strip is one of the most severe cases of salinization, as accelerated degradation of the water quality endangers the present and future water supply for over 1 million people. We investigate the chemical and isotopic (87Sr/86Sr, δ11B, δ18O, δ2H, and δ34SSO4) compositions of groundwater from the southern Mediterranean coastal aquifer (Israel) and the Gaza Strip in order to elucidate the origin of salinity and boron contamination. The original salinity in the eastern part of the aquifer is derived from discharge of saline groundwater from the adjacent Avedat aquitard (Na/Cl < 1, 87Sr/86Sr ˜ 0.7079, and δ11B ˜ 40‰). As the groundwater flows to the central part of the aquifer, a dramatic change in its composition occurs (Na/Cl > 1, high B/Cl, SO4/Cl, and HCO3, 87Sr/86Sr ˜ 0.7083; δ11B ˜ 48‰), although the δ18O-δ2H slope is identical to that of the Avedat aquitard. The geochemical data suggest that dissolution of pedogenic carbonate and gypsum minerals in the overlying loessial sequence generated the Ca-rich solution that triggered base exchange reactions and produced Na- and B-rich groundwater. The geochemical data show that most of the salinization process in the Gaza Strip is derived from the lateral flow of the Na-rich saline groundwater, superimposed with seawater intrusion and anthropogenic nitrate pollution. The methodology of identification of multiple salinity sources can be used to establish a long-term management plan for the Gaza Strip and can also be implemented to understand complex salinization processes in other similarly stressed coastal aquifers.

  9. Sources of salinity and boron in the Gaza strip: Natural contaminant flow in the southern Mediterranean coastal aquifer

    NASA Astrophysics Data System (ADS)

    Vengosh, Avner; Kloppmann, Wolfram; Marei, Amer; Livshitz, Yakov; Gutierrez, Alexis; Banna, Mazen; Guerrot, Catherine; Pankratov, Irena; Raanan, Hadas

    2005-01-01

    Salinization in coastal aquifers is a global phenomenon resulting from the overexploitation of scarce water resources. The Gaza Strip is one of the most severe cases of salinization, as accelerated degradation of the water quality endangers the present and future water supply for over 1 million people. We investigate the chemical and isotopic (87Sr/86Sr, δ11B, δ18O, δ2H, and δ34SSO4) compositions of groundwater from the southern Mediterranean coastal aquifer (Israel) and the Gaza Strip in order to elucidate the origin of salinity and boron contamination. The original salinity in the eastern part of the aquifer is derived from discharge of saline groundwater from the adjacent Avedat aquitard (Na/Cl < 1, 87Sr/86Sr ~ 0.7079, and δ11B ~ 40‰). As the groundwater flows to the central part of the aquifer, a dramatic change in its composition occurs (Na/Cl > 1, high B/Cl, SO4/Cl, and HCO3, 87Sr/86Sr ~ 0.7083; δ11B ~ 48‰), although the δ18O-δ2H slope is identical to that of the Avedat aquitard. The geochemical data suggest that dissolution of pedogenic carbonate and gypsum minerals in the overlying loessial sequence generated the Ca-rich solution that triggered base exchange reactions and produced Na- and B-rich groundwater. The geochemical data show that most of the salinization process in the Gaza Strip is derived from the lateral flow of the Na-rich saline groundwater, superimposed with seawater intrusion and anthropogenic nitrate pollution. The methodology of identification of multiple salinity sources can be used to establish a long-term management plan for the Gaza Strip and can also be implemented to understand complex salinization processes in other similarly stressed coastal aquifers.

  10. Resource competition model predicts zonation and increasing nutrient use efficiency along a wetland salinity gradient

    USGS Publications Warehouse

    Schoolmaster, Donald; Stagg, Camille L.

    2018-01-01

    A trade-off between competitive ability and stress tolerance has been hypothesized and empirically supported to explain the zonation of species across stress gradients for a number of systems. Since stress often reduces plant productivity, one might expect a pattern of decreasing productivity across the zones of the stress gradient. However, this pattern is often not observed in coastal wetlands that show patterns of zonation along a salinity gradient. To address the potentially complex relationship between stress, zonation, and productivity in coastal wetlands, we developed a model of plant biomass as a function of resource competition and salinity stress. Analysis of the model confirms the conventional wisdom that a trade-off between competitive ability and stress tolerance is a necessary condition for zonation. It also suggests that a negative relationship between salinity and production can be overcome if (1) the supply of the limiting resource increases with greater salinity stress or (2) nutrient use efficiency increases with increasing salinity. We fit the equilibrium solution of the dynamic model to data from Louisiana coastal wetlands to test its ability to explain patterns of production across the landscape gradient and derive predictions that could be tested with independent data. We found support for a number of the model predictions, including patterns of decreasing competitive ability and increasing nutrient use efficiency across a gradient from freshwater to saline wetlands. In addition to providing a quantitative framework to support the mechanistic hypotheses of zonation, these results suggest that this simple model is a useful platform to further build upon, simulate and test mechanistic hypotheses of more complex patterns and phenomena in coastal wetlands.

  11. UV/TiO₂ photocatalytic oxidation of recalcitrant organic matter: effect of salinity and pH.

    PubMed

    Muthukumaran, Shobha; Song, Lili; Zhu, Bo; Myat, Darli; Chen, Jin-Yuan; Gray, Stephen; Duke, Mikel

    2014-01-01

    Photocatalytic oxidation processes have interest for water treatment since these processes can remove recalcitrant organic compounds and operate at mild conditions of temperature and pressure. However, performance under saline conditions present in many water resources is not well known. This study aims to explore the basic effects of photocatalysis on the removal of organic matter in the presence of salt. A laboratory-scale photocatalytic reactor system, employing ultraviolet (UV)/titanium dioxide (TiO₂) photocatalysis was evaluated for its ability to remove the humic acid (HA) from saline water. The particle size and zeta potential of TiO₂ under different conditions including solution pH and sodium chloride (NaCl) concentrations were characterized. The overall degradation of organics over the NaCl concentration range of 500-2,000 mg/L was found to be 80% of the non-saline equivalent after 180 min of the treatment. The results demonstrated that the adsorption of HA onto the TiO₂ particles was dependent on both the pH and salinity due to electrostatic interaction and highly unstable agglomerated dispersion. This result supports UV/TiO₂ as a viable means to remove organic compounds, but the presence of salt in waters to be treated will influence the performance of the photocatalytic oxidation process.

  12. Coordinating management of water, salinity and trace elements for cotton under mulched drip irrigation with brackish water

    NASA Astrophysics Data System (ADS)

    Jin, M.; Chen, W.; Liang, X.

    2016-12-01

    Rational irrigation with brackish water can increase crop production, but irrational use may cause soil salinization. In order to understand the relationships among water, salt, and nutrient (including trace elements) and find rational schemes to manage water, salinity and nutrient in cotton fields, field and pot experiments were conducted in an arid area of southern Xinjiang, northwest China. Field experiments were performed from 2008 to 2015, and involved mulched drip irrigation during the growing season and flood irrigation afterwards. The average cotton yield of seven years varied between 3,575 and 5,095 kg/ha, and the irrigation water productivity between 0.91 and 1.16 kg/m3. With the progress of brackish water irrigation, Cu, Fe, Mn, and Na showed strong aggregation in topsoil at the narrow row, whereas the contents of Ca and K decreased in the order of inter-mulch gap, the wide inter row, and the narrow row. The contents of Cu, Fe, Mn, Ca and K in root soil reduced with cotton growth, whereas Na increased. Although mulched drip irrigation during the growing season resulted in an increase in salinity in the root zone, flood irrigation after harvesting leached the accumulated salts below background levels. Based on experiments a scheme for coordinating management of soil water, salt, and nutrient is proposed, that is, under the planting pattern of one mulch, two drip lines and four rows, the alternative irrigation plus a flood irrigation after harvesting or before seeding was the ideal scheme. Numerical simulations using solute transport model coupled with the root solute uptake based on the experiments and extended by another 20 years, suggest that the mulched drip irrigation using alternatively fresh and brackish water during the growing season and flood irrigation with fresh water after harvesting, is a sustainable irrigation practice that should not lead to soil salinization. Pot experiments with trace elements and different saline water showed

  13. Inferring soil salinity in a drip irrigation system from multi-configuration EMI measurements using adaptive Markov chain Monte Carlo

    NASA Astrophysics Data System (ADS)

    Zaib Jadoon, Khan; Umer Altaf, Muhammad; McCabe, Matthew Francis; Hoteit, Ibrahim; Muhammad, Nisar; Moghadas, Davood; Weihermüller, Lutz

    2017-10-01

    A substantial interpretation of electromagnetic induction (EMI) measurements requires quantifying optimal model parameters and uncertainty of a nonlinear inverse problem. For this purpose, an adaptive Bayesian Markov chain Monte Carlo (MCMC) algorithm is used to assess multi-orientation and multi-offset EMI measurements in an agriculture field with non-saline and saline soil. In MCMC the posterior distribution is computed using Bayes' rule. The electromagnetic forward model based on the full solution of Maxwell's equations was used to simulate the apparent electrical conductivity measured with the configurations of EMI instrument, the CMD Mini-Explorer. Uncertainty in the parameters for the three-layered earth model are investigated by using synthetic data. Our results show that in the scenario of non-saline soil, the parameters of layer thickness as compared to layers electrical conductivity are not very informative and are therefore difficult to resolve. Application of the proposed MCMC-based inversion to field measurements in a drip irrigation system demonstrates that the parameters of the model can be well estimated for the saline soil as compared to the non-saline soil, and provides useful insight about parameter uncertainty for the assessment of the model outputs.

  14. Evaluation of soil salinity amelioration technologies in Timpaki, Crete: a participatory approach

    NASA Astrophysics Data System (ADS)

    Panagea, I. S.; Daliakopoulos, I. N.; Tsanis, I. K.; Schwilch, G.

    2015-10-01

    Soil salinity management can be complex, expensive and time demanding, especially in arid and semi-arid regions. Besides taking no action, possible management strategies include amelioration and adaptation measures. Here we use the World Overview of Conservation Approaches and Technologies (WOCAT) framework for the systematic analysis and evaluation of soil salinisation amelioration technologies in close collaboration with stakeholders. The participatory approach is applied in the RECARE Project Case Study of Timpaki, a semi-arid region in south-central Crete (Greece) where the main land use is horticulture in greenhouses irrigated by groundwater. Excessive groundwater abstractions have resulted in a drop of the groundwater level in the coastal part of the aquifer, thus leading to seawater intrusion and in turn to soil salinisation. The documented technologies are evaluated for their impacts on ecosystem services, cost and input requirements using a participatory approach and field evaluations. Results show that technologies which promote maintaining existing crop types while enhancing productivity and decreasing soil salinity are preferred by the stakeholders. The evaluation concludes that rain water harvesting is the optimal solution for direct soil salinity mitigation, whereas green manuring and the use of biological agents can support increasing production/efficiency and improving soil properties.

  15. Reconstructing Past Ocean Salinity ((delta)18Owater)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Guilderson, T P; Pak, D K

    2005-11-23

    Temperature and salinity are two of the key properties of ocean water masses. The distribution of these two independent but related characteristics reflects the interplay of incoming solar radiation (insolation) and the uneven distribution of heat loss and gain by the ocean, with that of precipitation, evaporation, and the freezing and melting of ice. Temperature and salinity to a large extent, determine the density of a parcel of water. Small differences in temperature and salinity can increase or decrease the density of a water parcel, which can lead to convection. Once removed from the surface of the ocean where 'local'more » changes in temperature and salinity can occur, the water parcel retains its distinct relationship between (potential) temperature and salinity. We can take advantage of this 'conservative' behavior where changes only occur as a result of mixing processes, to track the movement of water in the deep ocean (Figure 1). The distribution of density in the ocean is directly related to horizontal pressure gradients and thus (geostrophic) ocean currents. During the Quaternary when we have had systematic growth and decay of large land based ice sheets, salinity has had to change. A quick scaling argument following that of Broecker and Peng [1982] is: the modern ocean has a mean salinity of 34.7 psu and is on average 3500m deep. During glacial maxima sea level was on the order of {approx}120m lower than present. Simply scaling the loss of freshwater (3-4%) requires an average increase in salinity a similar percentage or to {approx}35.9psu. Because much of the deep ocean is of similar temperature, small changes in salinity have a large impact on density, yielding a potentially different distribution of water masses and control of the density driven (thermohaline) ocean circulation. It is partly for this reason that reconstructions of past salinity are of interest to paleoceanographers.« less

  16. Runoff and solute mobilization processes in a semiarid headwater catchment

    NASA Astrophysics Data System (ADS)

    Hughes, Justin D.; Khan, Shahbaz; Crosbie, Russell S.; Helliwell, Stuart; Michalk, David L.

    2007-09-01

    Runoff and solute transport processes contributing to streamflow were determined in a small headwater catchment in the eastern Murray-Darling Basin of Australia using hydrometric and tracer methods. Streamflow and electrical conductivity were monitored from two gauges draining a portion of the upper catchment area (UCA) and a saline scalded area, respectively. Runoff in the UCA was related to the formation of a seasonally perched aquifer in the near-surface zone (0-0.4 m). A similar process was responsible for runoff generation in the saline scalded area. However, saturation in the scald area was related to the proximity of groundwater rather than low subsurface hydraulic conductivity. Because of higher antecedent water content, runoff commenced earlier in winter from the scald than did the UCA. Additionally, areal runoff from the scald was far greater than from the UCA. Total runoff from the UCA was higher than the scald (15.7 versus 3.5 mL), but salt export was far lower (0.6 and 5.4 t for the UCA and scald area, respectively) since salinity of the scald runoff was far higher than that from the UCA, indicating the potential impact of saline scalded areas at the catchment scale. End-member mixing analysis modeling using six solutes indicated that most runoff produced from the scald was "new" (40-71%) despite the proximity of the groundwater surface and the high antecedent moisture levels. This is a reflection of the very low hydraulic conductivity of soils in the study area. Nearly all chloride exported to the stream from the scald emanated from the near-surface zone (77-87%). Runoff and solute mobilization processes depend upon seasonal saturation occurring in the near-surface zone during periods of low evaporative demand and generation of saturated overland flow.

  17. Effect of water content on the glass transition temperature of mixtures of sugars, polymers, and penetrating cryoprotectants in physiological buffer.

    PubMed

    Drake, Andrew C; Lee, Youngjoo; Burgess, Emma M; Karlsson, Jens O M; Eroglu, Ali; Higgins, Adam Z

    2018-01-01

    Long-term storage of viable mammalian cells is important for applications ranging from in vitro fertilization to cell therapy. Cryopreservation is currently the most common approach, but storage in liquid nitrogen is relatively costly and the requirement for low temperatures during shipping is inconvenient. Desiccation is an alternative strategy with the potential to enable viable cell preservation at more convenient storage temperatures without the need for liquid nitrogen. To achieve stability during storage in the dried state it is necessary to remove enough water that the remaining matrix forms a non-crystalline glassy solid. Thus, the glass transition temperature is a key parameter for design of cell desiccation procedures. In this study, we have investigated the effects of moisture content on the glass transition temperature (Tg) of mixtures of sugars (trehalose or raffinose), polymers (polyvinylpyrrolidone or Ficoll), penetrating cryoprotectants (ethylene glycol, propylene glycol, or dimethyl sulfoxide), and phosphate buffered saline (PBS) solutes. Aqueous solutions were dried to different moisture contents by equilibration with saturated salt solutions, or by baking at 95°C. The glass transition temperatures of the dehydrated samples were then measured by differential scanning calorimetry. As expected, Tg increased with decreasing moisture content. For example, in a desiccation medium containing 0.1 M trehalose in PBS, Tg ranged from about 360 K for a completely dry sample to about 220 K at a water mass fraction of 0.4. Addition of polymers to the solutions increased Tg, while addition of penetrating cryoprotectants decreased Tg. Our results provide insight into the relationship between relative humidity, moisture content and glass transition temperature for cell desiccation solutions containing sugars, polymers and penetrating cryoprotectants.

  18. Effect of water content on the glass transition temperature of mixtures of sugars, polymers, and penetrating cryoprotectants in physiological buffer

    PubMed Central

    Burgess, Emma M.; Karlsson, Jens O. M.; Eroglu, Ali

    2018-01-01

    Long-term storage of viable mammalian cells is important for applications ranging from in vitro fertilization to cell therapy. Cryopreservation is currently the most common approach, but storage in liquid nitrogen is relatively costly and the requirement for low temperatures during shipping is inconvenient. Desiccation is an alternative strategy with the potential to enable viable cell preservation at more convenient storage temperatures without the need for liquid nitrogen. To achieve stability during storage in the dried state it is necessary to remove enough water that the remaining matrix forms a non-crystalline glassy solid. Thus, the glass transition temperature is a key parameter for design of cell desiccation procedures. In this study, we have investigated the effects of moisture content on the glass transition temperature (Tg) of mixtures of sugars (trehalose or raffinose), polymers (polyvinylpyrrolidone or Ficoll), penetrating cryoprotectants (ethylene glycol, propylene glycol, or dimethyl sulfoxide), and phosphate buffered saline (PBS) solutes. Aqueous solutions were dried to different moisture contents by equilibration with saturated salt solutions, or by baking at 95°C. The glass transition temperatures of the dehydrated samples were then measured by differential scanning calorimetry. As expected, Tg increased with decreasing moisture content. For example, in a desiccation medium containing 0.1 M trehalose in PBS, Tg ranged from about 360 K for a completely dry sample to about 220 K at a water mass fraction of 0.4. Addition of polymers to the solutions increased Tg, while addition of penetrating cryoprotectants decreased Tg. Our results provide insight into the relationship between relative humidity, moisture content and glass transition temperature for cell desiccation solutions containing sugars, polymers and penetrating cryoprotectants. PMID:29304068

  19. Microfluidic Fabrication of Cell Adhesive Chitosan Microtubes

    PubMed Central

    Oh, Jonghyun; Kim, Keekyoung; Won, Sung Wook; Cha, Chaenyung; Gaharwar, Akhilesh; Selimović, Šeila; Bae, Hojae; Lee, Kwang Ho; Lee, Dong Hwan; Lee, Sang-Hoon; Khademhosseini, Ali

    2013-01-01

    Chitosan has been used as a scaffolding material in tissue engineering due to its mechanical properties and biocompatibility. With increased appreciation of the effect of micro- and nanoscale environments on cellular behavior, there is increased emphasis on generating microfabricated chitosan structures. Here we employed a microfluidic coaxial flow-focusing system to generate cell adhesive chitosan microtubes of controlled sizes by modifying the flow rates of a chitosan pre-polymer solution and phosphate buffered saline (PBS). The microtubes were extruded from a glass capillary with a 300 μm inner diameter. After ionic crosslinking with sodium tripolyphosphate (TPP), fabricated microtubes had inner and outer diameter ranges of 70-150 μm and 120-185 μm. Computational simulation validated the controlled size of microtubes and cell attachment. To enhance cell adhesiveness on the microtubes, we mixed gelatin with the chitosan pre-polymer solution and adjusted the pH values of the chitosan pre-polymer solution with gelatin and TPP. During the fabrication of microtubes, fibroblasts suspended in core PBS flow adhered to the inner surface of chitosan-gelatin microtubes. To achieve physiological pH values, we adjusted pH values of chiotsan pre-polymer solution and TPP. In particular, we were able to improve cell viability to 92% with pH values of 5.8 and 7.4 for chitosan and TPP solution respectively. Cell culturing for three days showed that the addition of the gelatin enhanced cell spreading and proliferation inside the chitosan-gelatin microtubes. The microfluidic fabrication method for ionically crosslinked chitosan microtubes at physiological pH can be compatible with a variety of cells and used as a versatile platform for microengineered tissue engineering. PMID:23355068

  20. A novel polarization demodulation method using polarization beam splitter (PBS) for dynamic pressure sensor

    NASA Astrophysics Data System (ADS)

    Su, Yang; Zhou, Hua; Wang, Yiming; Shen, Huiping

    2018-03-01

    In this paper we propose a new design to demodulate polarization properties induced by pressure using a PBS (polarization beam splitter), which is different with traditional polarimeter based on the 4-detector polarization measurement approach. The theoretical model is established by Muller matrix method. Experimental results confirm the validity of our analysis. Proportional relationships and linear fit are found between output signal and applied pressure. A maximum sensitivity of 0.092182 mv/mv is experimentally achieved and the frequency response exhibits a <0.14 dB variation across the measurement bandwidth. The sensitivity dependence on incident SOP (state of polarization) is investigated. The simple and all-fiber configuration, low-cost and high speed potential make it promising for fiber-based dynamic pressure sensing.