Operando Spectromicroscopy of Sulfur Species in Lithium-Sulfur Batteries

DOE PAGES

Miller, Elizabeth C.; Kasse, Robert M.; Heath, Khloe N.; ...

2017-11-03

Here, a novel cross-sectional battery cell was developed to characterize lithium-sulfur batteries using X-ray spectromicroscopy. Chemically sensitive X-ray maps were collected operando at energies relevant to the expected sulfur species and were used to correlate changes in sulfur species with electrochemistry. Significant changes in the sulfur/carbon composite electrode were observed from cycle to cycle including rearrangement of the elemental sulfur matrix and PEO10LiTFSI binder. Polysulfide concentration and area of spatial diffusion increased with cycling, indicating that some polysulfide dissolution is irreversible, leading to polysulfide shuttle. Fitting of the maps using standard sulfur and polysulfide XANES spectra indicated that upon subsequentmore » discharge/charge cycles, the initial sulfur concentration was not fully recovered; polysulfides and lithium sulfide remained at the cathodes with higher order polysulfides as the primary species in the region of interest. Quantification of the polysulfide concentration across the electrolyte and electrode interfaces shows that the polysulfide concentration before the first discharge and after the third charge is constant within the electrolyte, but while cycling, a significant increase in polysulfides and a gradient toward the lithium metal anode forms. Finally, this chemically and spatially sensitive characterization and analysis provides a foundation for further operando spectromicroscopy of lithium-sulfur batteries.« less

Quantitative determination of polysulfide in albumins, plasma proteins and biological fluid samples using a novel combined assays approach.

PubMed

Ikeda, Mayumi; Ishima, Yu; Shibata, Akitomo; Chuang, Victor T G; Sawa, Tomohiro; Ihara, Hideshi; Watanabe, Hiroshi; Xian, Ming; Ouchi, Yuya; Shimizu, Taro; Ando, Hidenori; Ukawa, Masami; Ishida, Tatsuhiro; Akaike, Takaaki; Otagiri, Masaki; Maruyama, Toru

2017-05-29

Hydrogen sulfide (H 2 S) signaling involves polysulfide (RSS n SR') formation on various proteins. However, the current lack of sensitive polysulfide detection assays poses methodological challenges for understanding sulfane sulfur homeostasis and signaling. We developed a novel combined assay by modifying Sulfide Antioxidant Buffer (SAOB) to produce an "Elimination Method of Sulfide from Polysulfide" (EMSP) treatment solution that liberates sulfide, followed with methylene blue (MB) sulfide detection assay. The combined EMSP-MB sulfide detection assay performed on low molecular weight sulfur species showed that sulfide was produced from trisulfide compounds such as glutathione trisulfide and diallyl trisulfide, but not from the thiol compounds such as cysteine, cystine and glutathione. In the case of plasma proteins, this novel combined detection assay revealed that approximately 14.7, 1.7, 3.9, 3.7 sulfide mol/mol released from human serum albumin, α 1 -anti-trypsin, α 1 -acid glycoprotein and ovalbumin, respectively, suggesting that serum albumin is a major pool of polysulfide in human blood circulation. Taken together with the results of albumins of different species, the liberated sulfide has a good correlation with cysteine instead of methionine, indicating the site of incorporation of polysulfide is cysteine. With this novel sulfide detention assay, approximately 8,000, 120 and 1100 μM of polysulfide concentrations was quantitated in human healthy plasma, saliva and tear, respectively. Our promising polysulfide specific detection assay can be a very important tool because quantitative determination of polysulfide sheds light on the functional consequence of protein-bound cysteine polysulfide and expands the research area of reactive oxygen to reactive polysulfide species. Copyright © 2017 Elsevier B.V. All rights reserved.

High sulfur-containing carbon polysulfide polymer as a novel cathode material for lithium-sulfur battery.

PubMed

Zhang, Yiyong; Peng, Yueying; Wang, Yunhui; Li, Jiyang; Li, He; Zeng, Jing; Wang, Jing; Hwang, Bing Joe; Zhao, Jinbao

2017-09-12

The lithium-sulfur battery, which offers a high energy density and is environmental friendly, is a promising next generation of rechargeable energy storage system. However, despite these attractive attributes, the commercialization of lithium-sulfur battery is primarily hindered by the parasitic reactions between the Li metal anode and dissolved polysulfide species from the cathode during the cycling process. Herein, we synthesize the sulfur-rich carbon polysulfide polymer and demonstrate that it is a promising cathode material for high performance lithium-sulfur battery. The electrochemical studies reveal that the carbon polysulfide polymer exhibits superb reversibility and cycle stability. This is due to that the well-designed structure of the carbon polysulfide polymer has several advantages, especially, the strong chemical interaction between sulfur and the carbon framework (C-S bonds) inhibits the shuttle effect and the π electrons of the carbon polysulfide compound enhance the transfer of electrons and Li + . Furthermore, as-prepared carbon polysulfide polymer-graphene hybrid cathode achieves outstanding cycle stability and relatively high capacity. This work highlights the potential promise of the carbon polysulfide polymer as the cathode material for high performance lithium-sulfur battery.

Powering Lithium-Sulfur Battery Performance by Propelling Polysulfide Redox at Sulfiphilic Hosts.

PubMed

Yuan, Zhe; Peng, Hong-Jie; Hou, Ting-Zheng; Huang, Jia-Qi; Chen, Cheng-Meng; Wang, Dai-Wei; Cheng, Xin-Bing; Wei, Fei; Zhang, Qiang

2016-01-13

Lithium-sulfur (Li-S) battery system is endowed with tremendous energy density, resulting from the complex sulfur electrochemistry involving multielectron redox reactions and phase transformations. Originated from the slow redox kinetics of polysulfide intermediates, the flood of polysulfides in the batteries during cycling induced low sulfur utilization, severe polarization, low energy efficiency, deteriorated polysulfide shuttle, and short cycling life. Herein, sulfiphilic cobalt disulfide (CoS2) was incorporated into carbon/sulfur cathodes, introducing strong interaction between lithium polysulfides and CoS2 under working conditions. The interfaces between CoS2 and electrolyte served as strong adsorption and activation sites for polar polysulfides and therefore accelerated redox reactions of polysulfides. The high polysulfide reactivity not only guaranteed effective polarization mitigation and promoted energy efficiency by 10% but also promised high discharge capacity and stable cycling performance during 2000 cycles. A slow capacity decay rate of 0.034%/cycle at 2.0 C and a high initial capacity of 1368 mAh g(-1) at 0.5 C were achieved. Since the propelling redox reaction is not limited to Li-S system, we foresee the reported strategy herein can be applied in other high-power devices through the systems with controllable redox reactions.

Direct observation of lithium polysulfides in lithium-sulfur batteries using operando X-ray diffraction

NASA Astrophysics Data System (ADS)

Conder, Joanna; Bouchet, Renaud; Trabesinger, Sigita; Marino, Cyril; Gubler, Lorenz; Villevieille, Claire

2017-06-01

In the on going quest towards lithium-battery chemistries beyond the lithium-ion technology, the lithium-sulfur system is emerging as one of the most promising candidates. The major outstanding challenge on the route to commercialization is controlling the so-called polysulfide shuttle, which is responsible for the poor cycling efficiency of the current generation of lithium-sulfur batteries. However, the mechanistic understanding of the reactions underlying the polysulfide shuttle is still incomplete. Here we report the direct observation of lithium polysulfides in a lithium-sulfur cell during operation by means of operando X-ray diffraction. We identify signatures of polysulfides adsorbed on the surface of a glass-fibre separator and monitor their evolution during cycling. Furthermore, we demonstrate that the adsorption of the polysulfides onto SiO2 can be harnessed for buffering the polysulfide redox shuttle. The use of fumed silica as an electrolyte additive therefore significantly improves the specific charge and Coulombic efficiency of lithium-sulfur batteries.

Carbyne polysulfide as a novel cathode material for rechargeable magnesium batteries.

PubMed

NuLi, Yanna; Chen, Qiang; Wang, Weikun; Wang, Ying; Yang, Jun; Wang, Jiulin

2014-01-01

We report the formation of carbyne polysulfide by coheating carbon containing carbyne moieties and elemental sulfur. The product is proved to have a sp2 hybrid carbon skeleton with polysulfide attached on it. The electrochemical performance of carbyne polysulfide as a novel cathode material for rechargeable magnesium batteries is firstly investigated. The material exhibits a high discharge capacity of 327.7 mAh g(-1) at 3.9 mA g(-1). These studies show that carbyne polysulfide is a promising candidate as cathode material for rechargeable Mg batteries if the capacity retention can be significantly improved.

Zero VOC, Coal Tar Free Splash Zone Coating (SZC)

DTIC Science & Technology

2011-09-01

marketed a millable gum polysulfide known as the first synthetic rubber commercially made in the United States. Today, there are several liquid...polysulfide polymers have the same excellent overall solvent resistance properties as the millable gum polysulfides. However, the liquid polysulfides...to the epoxide group and displaces the tertiary amine to form a covalent sulfur-carbon bond. The tertiary amine is regenerated and is then available

Magnetic Field-Controlled Lithium Polysulfide Semiliquid Battery with Ferrofluidic Properties.

PubMed

Li, Weiyang; Liang, Zheng; Lu, Zhenda; Tao, Xinyong; Liu, Kai; Yao, Hongbin; Cui, Yi

2015-11-11

Large-scale energy storage systems are of critical importance for electric grids, especially with the rapid increasing deployment of intermittent renewable energy sources such as wind and solar. New cost-effective systems that can deliver high energy density and efficiency for such storage often involve the flow of redox molecules and particles. Enhancing the mass and electron transport is critical for efficient battery operation in these systems. Herein, we report the design and characterization of a novel proof-of-concept magnetic field-controlled flow battery using lithium metal-polysulfide semiliquid battery as an example. A biphasic magnetic solution containing lithium polysulfide and magnetic nanoparticles is used as catholyte, and lithium metal is used as anode. The catholyte is composed of two phases of polysulfide with different concentrations, in which most of the polysulfide molecules and the superparamagnetic iron oxide nanoparticles can be extracted together to form a high-concentration polysulfide phase, in close contact with the current collector under the influence of applied magnetic field. This unique feature can help to maximize the utilization of the polysulfide and minimize the polysulfide shuttle effect, contributing to enhanced energy density and Coulombic efficiency. Additionally, owing to the effect of the superparamagnetic nanoparticles, the concentrated polysulfide phase shows the behavior of a ferrofluid that is flowable with the control of magnetic field, which can be used for a hybrid flow battery without the employment of any pumps. Our innovative design provides new insight for a broad range of flow battery chemistries and systems.

A Novel Optical Diagnostic for In Situ Measurements of Lithium Polysulfides in Battery Electrolytes.

PubMed

Saqib, Najmus; Silva, Cody J; Maupin, C Mark; Porter, Jason M

2017-07-01

An optical diagnostic technique to determine the order and concentration of lithium polysulfides in lithium-sulfur (Li-S) battery electrolytes has been developed. One of the major challenges of lithium-sulfur batteries is the problem of polysulfide shuttling between the electrodes, which leads to self-discharge and loss of active material. Here we present an optical diagnostic for quantitative in situ measurements of lithium polysulfides using attenuated total reflection Fourier transform infrared (FT-IR) spectroscopy. Simulated infrared spectra of lithium polysulfide molecules were generated using computational quantum chemistry routines implemented in Gaussian 09. The theoretical spectra served as a starting point for experimental characterization of lithium polysulfide solutions synthesized by the direct reaction of lithium sulfide and sulfur. Attenuated total reflection FT-IR spectroscopy was used to measure absorption spectra. The lower limit of detection with this technique is 0.05 M. Measured spectra revealed trends with respect to polysulfide order and concentration, consistent with theoretical predictions, which were used to develop a set of equations relating the order and concentration of lithium polysulfides in a sample to the position and area of a characteristic infrared absorption band. The diagnostic routine can measure the order and concentration to within 5% and 0.1 M, respectively.

Carbyne Polysulfide as a Novel Cathode Material for Rechargeable Magnesium Batteries

PubMed Central

NuLi, Yanna; Chen, Qiang; Wang, Weikun; Wang, Ying; Yang, Jun; Wang, Jiulin

2014-01-01

We report the formation of carbyne polysulfide by coheating carbon containing carbyne moieties and elemental sulfur. The product is proved to have a sp2 hybrid carbon skeleton with polysulfide attached on it. The electrochemical performance of carbyne polysulfide as a novel cathode material for rechargeable magnesium batteries is firstly investigated. The material exhibits a high discharge capacity of 327.7 mAh g−1 at 3.9 mA g−1. These studies show that carbyne polysulfide is a promising candidate as cathode material for rechargeable Mg batteries if the capacity retention can be significantly improved. PMID:24587704

Improvement of Cycling Performance of Lithium-Sulfur Batteries by Using Magnesium Oxide as a Functional Additive for Trapping Lithium Polysulfide.

PubMed

Ponraj, Rubha; Kannan, Aravindaraj G; Ahn, Jun Hwan; Kim, Dong-Won

2016-02-17

Trapping lithium polysulfides formed in the sulfur positive electrode of lithium-sulfur batteries is one of the promising approaches to overcome the issues related to polysulfide dissolution. In this work, we demonstrate that intrinsically hydrophilic magnesium oxide (MgO) nanoparticles having surface hydroxyl groups can be used as effective additives to trap lithium polysulfides in the positive electrode. MgO nanoparticles were uniformly distributed on the surface of the active sulfur, and the addition of MgO into the sulfur electrode resulted in an increase in capacity retention of the lithium-sulfur cell compared to a cell with pristine sulfur electrode. The improvement in cycling stability was attributed to the strong chemical interactions between MgO and lithium polysulfide species, which suppressed the shuttling effect of lithium polysulfides and enhanced the utilization of the sulfur active material. To the best of our knowledge, this report is the first demonstration of MgO as an effective functional additive to trap lithium polysulfides in lithium-sulfur cells.

Elucidating the Electrochemical Activity of Electrolyte-Insoluble Polysulfide Species in Lithium-Sulfur Batteries

DOE PAGES

Klein, Michael J.; Goossens, Karel; Bielawski, Christopher W.; ...

2016-07-29

The direct synthesis of Li 2S 2, a proposed solid intermediate in the discharge of lithium-sulfur (Li-S) batteries, was accomplished by treating elemental lithium with sulfur in liquid ammonia at -41°C. The as-synthesized product was analyzed by X-ray photoelectron spectroscopy (XPS) as well as X-ray diffraction (XRD) and determined to be a mixture of crystalline Li 2S, amorphous Li 2S 2, and higher-order polysulfides (Li 2S x, x > 2). Monitored filtration followed by a tailored electrochemical approach was used to successfully remove the higher-order polysulfides and yielded a powder, which was determined by XPS to be comprised of ~9more » mol% insoluble polysulfide species (mainly Li 2S 2) and ~91 mol% Li 2S. Here, this material was discharged galvanostatically in an electrochemical cell and, despite the lack of soluble polysulfide species, was shown to exhibit a discharge plateau at ~2.1 V vs. Li/Li +. This result confirmed the electrochemical reducibility of electrolyte-insoluble polysulfides in Li-S batteries. Moreover, it was determined that the reduction of solid polysulfides was confined to areas where the sulfur-sulfur bonds were in intimate contact with the conductive current collector. Finally, it was observed that commercially available Li 2S samples contain significant quantities of polysulfide-type impurities.« less

Nucleophilic substitution between polysulfides and binders unexpectedly stabilizing lithium sulfur battery

DOE PAGES

Ling, Min; Zhang, Liang; Zheng, Tianyue; ...

2017-05-10

Polysulfide shuttling has been the primary cause of failure in lithium-sulfur (Li-S) battery cycling. In this paper, we demonstrate an nucleophilic substitution reaction between polysulfides and binder functional groups can unexpectedly immobilizes the polysulfides. The substitution reaction is verified by UV–visible spectra and X-ray photoelectron spectra. The immobilization of polysulfide is in situ monitored by synchrotron based sulfur K-edge X-ray absorption spectra. The resulting electrodes exhibit initial capacity up to 20.4 mAh/cm 2, corresponding to 1199.1 mAh/g based on a micron-sulfur mass loading of 17.0 mg/cm 2. The micron size sulfur transformed into nano layer coating on the cathode bindermore » during cycling. Directly usage of nano-size sulfur promotes higher capacity of 33.7 mAh/cm 2, which is the highest areal capacity reported in Li-S battery. Finally, this enhance performance is due to the reduced shuttle effect by covalently binding of the polysulfide with the polymer binder.« less

Nucleophilic substitution between polysulfides and binders unexpectedly stabilizing lithium sulfur battery

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

Ling, Min; Zhang, Liang; Zheng, Tianyue

Polysulfide shuttling has been the primary cause of failure in lithium-sulfur (Li-S) battery cycling. In this paper, we demonstrate an nucleophilic substitution reaction between polysulfides and binder functional groups can unexpectedly immobilizes the polysulfides. The substitution reaction is verified by UV–visible spectra and X-ray photoelectron spectra. The immobilization of polysulfide is in situ monitored by synchrotron based sulfur K-edge X-ray absorption spectra. The resulting electrodes exhibit initial capacity up to 20.4 mAh/cm 2, corresponding to 1199.1 mAh/g based on a micron-sulfur mass loading of 17.0 mg/cm 2. The micron size sulfur transformed into nano layer coating on the cathode bindermore » during cycling. Directly usage of nano-size sulfur promotes higher capacity of 33.7 mAh/cm 2, which is the highest areal capacity reported in Li-S battery. Finally, this enhance performance is due to the reduced shuttle effect by covalently binding of the polysulfide with the polymer binder.« less

Self-Assembled Protein Nanofilter for Trapping Polysulfides and Promoting Li+ Transport in Lithium-Sulfur Batteries.

PubMed

Fu, Xuewei; Li, Chunhui; Wang, Yu; Scudiero, Louis; Liu, Jin; Zhong, Wei-Hong

2018-05-17

The diffusion of polysulfides in lithium-sulfur (Li-S) batteries represents a critical issue deteriorating the electrochemical performance. Here, borrowing the concepts from air filtration, we design and fabricate a protein-based nanofilter for effectively trapping polysulfides but facilitating Li + transport. The unique porous structures are formed through a protein-directed self-assembly process, and the surfaces are functionalized by the protein residues. The experiments and molecular simulation results demonstrate that our polysulfide nanofilter can effectively trap the dissolved polysulfides and promote Li + transport in Li-S batteries. When the polysulfide nanofilter is added in a Li-S battery, the electrochemical performance of the battery is significantly improved. Moreover, the contribution of the protein nanofilter to the ion transport is further analyzed by correlating filter properties and battery performance. This study is of universal significance for the understanding, design, and fabrication of advanced battery interlayers that can help realize good management of the ion transport inside advanced energy storage devices.

Optimization of Pore Structure of Cathodic Carbon Supports for Solvate Ionic Liquid Electrolytes Based Lithium-Sulfur Batteries.

PubMed

Zhang, Shiguo; Ikoma, Ai; Li, Zhe; Ueno, Kazuhide; Ma, Xiaofeng; Dokko, Kaoru; Watanabe, Masayoshi

2016-10-04

Lithium-sulfur (Li-S) batteries are a promising energy-storage technology owing to their high theoretical capacity and energy density. However, their practical application remains a challenge because of the serve shuttle effect caused by the dissolution of polysulfides in common organic electrolytes. Polysulfide-insoluble electrolytes, such as solvate ionic liquids (ILs), have recently emerged as alternative candidates and shown great potential in suppressing the shuttle effect and improving the cycle stability of Li-S batteries. Redox electrochemical reactions in polysulfide-insoluble electrolytes occur via a solid-state process at the interphase between the electrolyte and the composite cathode; therefore, creating an appropriate interface between sulfur and a carbon support is of great importance. Nevertheless, the porous carbon supports established for conventional organic electrolytes may not be suitable for polysulfide-insoluble electrolytes. In this work, we investigated the effect of the porous structure of carbon materials on the Li-S battery performance in polysulfide-insoluble electrolytes using solvate ILs as a model electrolyte. We determined that the pore volume (rather than the surface area) exerts a major influence on the discharge capacity of S composite cathodes. In particular, inverse opal carbons with three-dimensionally ordered interconnected macropores and a large pore volume deliver the highest discharge capacity. The battery performance in both polysulfide-soluble electrolytes and solvate ILs was used to study the effect of electrolytes. We propose a plausible mechanism to explain the different porous structure requirements in polysulfide-soluble and polysulfide-insoluble electrolytes.

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Polysulfide polymer-polyepoxy resins. 177.1650... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1650 Polysulfide polymer...

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Polysulfide polymer-polyepoxy resins. 177.1650... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1650 Polysulfide polymer...

21 CFR 177.1650 - Polysulfide polymer-polyepoxy resins.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Polysulfide polymer-polyepoxy resins. 177.1650... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as Basic Components of Single and Repeated Use Food Contact Surfaces § 177.1650 Polysulfide polymer...

Polysulfide intercalated layered double hydroxides for metal capture applications

DOEpatents

Kanatzidis, Mercouri G.; Ma, Shulan

2017-04-04

Polysulfide intercalated layered double hydroxides and methods for their use in vapor and liquid-phase metal capture applications are provided. The layered double hydroxides comprise a plurality of positively charged host layers of mixed metal hydroxides separated by interlayer spaces. Polysulfide anions are intercalated in the interlayer spaces.

Surface Chemistry in Cobalt Phosphide-Stabilized Lithium-Sulfur Batteries.

PubMed

Zhong, Yiren; Yin, Lichang; He, Peng; Liu, Wen; Wu, Zishan; Wang, Hailiang

2018-01-31

Chemistry at the cathode/electrolyte interface plays an important role for lithium-sulfur batteries in which stable cycling of the sulfur cathode requires confinement of the lithium polysulfide intermediates and their fast electrochemical conversion on the electrode surface. While many materials have been found to be effective for confining polysulfides, the underlying chemical interactions remain poorly understood. We report a new and general lithium polysulfide-binding mechanism enabled by surface oxidation layers of transition-metal phosphide and chalcogenide materials. We for the first time find that CoP nanoparticles strongly adsorb polysulfides because their natural oxidation (forming Co-O-P-like species) activates the surface Co sites for binding polysulfides via strong Co-S bonding. With a surface oxidation layer capable of confining polysulfides and an inner core suitable for conducting electrons, the CoP nanoparticles are thus a desirable candidate for stabilizing and improving the performance of sulfur cathodes in lithium-sulfur batteries. We demonstrate that sulfur electrodes that hold a high mass loading of 7 mg cm -2 and a high areal capacity of 5.6 mAh cm -2 can be stably cycled for 200 cycles. We further reveal that this new surface oxidation-induced polysulfide-binding scheme applies to a series of transition-metal phosphide and chalcogenide materials and can explain their stabilizing effects for lithium-sulfur batteries.

Enhanced kinetics of polysulfide redox reactions on Mo2C/CNT in lithium-sulfur batteries.

PubMed

Razaq, Rameez; Sun, Dan; Xin, Ying; Li, Qian; Huang, Taizhong; Zheng, Lei; Zhang, Zhaoliang; Huang, Yunhui

2018-07-20

Among different energy storage devices, the lithium-sulfur (Li-S) battery is the subject of recent attention. However, the capacity decay caused by polysulfide shuttle leading to sluggish kinetics of polysulfide redox reactions is the main hindrance for its practical application in Li-S batteries. Herein, molybdenum carbide nanoparticles anchored on carbon nanotubes (Mo 2 C/CNT) are reported to serve as an efficient cathode material to enhance the electrochemical kinetics of polysulfide conversion in Li-S batteries. Mo 2 C/CNT shows strong adsorption and activation of polar polysulfides and therefore accelerates the redox kinetics of polysulfides, reduces the energy barrier, effectively mitigates the polarization and polysulfide shuttle, thus improving the electrochemical performance. The S-Mo 2 C/CNT composite with 70 wt% sulfur loading exhibits high specific discharge capacity (1206 mA h g -1 at 0.5 C), excellent high-rate performance, long cycle life (900 cycles), and outstanding Coulombic efficiency (∼100%) at a high rate (2 C) corresponding to a capacity decay of only 0.05%. Remarkably, the S-Mo 2 C/CNT cathode with high areal sulfur loading of 2.5 mg cm -2 exhibits high-rate capacities and stable cycling performance over 100 cycles, offering the potential for use in high energy Li-S batteries.

Enhanced kinetics of polysulfide redox reactions on Mo2C/CNT in lithium–sulfur batteries

NASA Astrophysics Data System (ADS)

Razaq, Rameez; Sun, Dan; Xin, Ying; Li, Qian; Huang, Taizhong; Zheng, Lei; Zhang, Zhaoliang; Huang, Yunhui

2018-07-01

Among different energy storage devices, the lithium–sulfur (Li–S) battery is the subject of recent attention. However, the capacity decay caused by polysulfide shuttle leading to sluggish kinetics of polysulfide redox reactions is the main hindrance for its practical application in Li–S batteries. Herein, molybdenum carbide nanoparticles anchored on carbon nanotubes (Mo2C/CNT) are reported to serve as an efficient cathode material to enhance the electrochemical kinetics of polysulfide conversion in Li–S batteries. Mo2C/CNT shows strong adsorption and activation of polar polysulfides and therefore accelerates the redox kinetics of polysulfides, reduces the energy barrier, effectively mitigates the polarization and polysulfide shuttle, thus improving the electrochemical performance. The S-Mo2C/CNT composite with 70 wt% sulfur loading exhibits high specific discharge capacity (1206 mA h g‑1 at 0.5 C), excellent high-rate performance, long cycle life (900 cycles), and outstanding Coulombic efficiency (∼100%) at a high rate (2 C) corresponding to a capacity decay of only 0.05%. Remarkably, the S-Mo2C/CNT cathode with high areal sulfur loading of 2.5 mg cm‑2 exhibits high-rate capacities and stable cycling performance over 100 cycles, offering the potential for use in high energy Li–S batteries.

A Lithium/Polysulfide Battery with Dual-Working Mode Enabled by Liquid Fuel and Acrylate-Based Gel Polymer Electrolyte.

PubMed

Liu, Ming; Ren, Yuxun; Zhou, Dong; Jiang, Haoran; Kang, Feiyu; Zhao, Tianshou

2017-01-25

The low density associated with low sulfur areal loading in the solid-state sulfur cathode of current Li-S batteries is an issue hindering the development of this type of battery. Polysulfide catholyte as a recyclable liquid fuel was proven to enhance both the energy density and power density of the battery. However, a critical barrier with this lithium (Li)/polysulfide battery is that the shuttle effect, which is the crossover of polysulfides and side deposition on the Li anode, becomes much more severe than that in conventional Li-S batteries with a solid-state sulfur cathode. In this work, we successfully applied an acrylate-based gel polymer electrolyte (GPE) to the Li/polysulfide system. The GPE layer can effectively block the detrimental diffusion of polysulfides and protect the Li metal from the side passivation reaction. Cathode-static batteries utilizing 2 M catholyte (areal sulfur loading of 6.4 mg cm -2 ) present superior cycling stability (727.4 mAh g -1 after 500 cycles at 0.2 C) and high rate capability (814 mAh g -1 at 2 C) and power density (∼10 mW cm -2 ), which also possess replaceable and encapsulated merits for mobile devices. In the cathode-flow mode, the Li/polysulfide system with catholyte supplied from an external tank demonstrates further improved power density (∼69 mW cm -2 ) and stable cycling performance. This novel and simple Li/polysulfide system represents a significant advancement of high energy density sulfur-based batteries for future power sources.

Molecularly Imprinted Polymer Enables High-Efficiency Recognition and Trapping Lithium Polysulfides for Stable Lithium Sulfur Battery.

PubMed

Liu, Jie; Qian, Tao; Wang, Mengfan; Liu, Xuejun; Xu, Na; You, Yizhou; Yan, Chenglin

2017-08-09

Using molecularly imprinted polymer to recognize various target molecules emerges as a fascinating research field. Herein, we applied this strategy for the first time to efficiently recognize and trap long-chain polysulfides (Li 2 S x , x = 6-8) in lithium sulfur battery to minimize the polysulfide shuttling between anode and cathode, which enables us to achieve remarkable electrochemical performance including a high specific capacity of 1262 mAh g -1 at 0.2 C and superior capacity retention of over 82.5% after 400 cycles at 1 C. The outstanding performance is attributed to the significantly reduced concentration of long-chain polysulfides in electrolyte as evidenced by in situ UV/vis spectroscopy and Li 2 S nucleation tests, which were further confirmed by density functional theory calculations. The molecular imprinting is demonstrated as a promising approach to effectively prevent the free diffusion of long-chain polysulfides, providing a new avenue to efficiently recognize and trap lithium polysulfides for high-performance lithium sulfur battery with greatly suppressed shuttle effect.

A sulfur host based on titanium monoxide@carbon hollow spheres for advanced lithium-sulfur batteries.

PubMed

Li, Zhen; Zhang, Jintao; Guan, Buyuan; Wang, Da; Liu, Li-Min; Lou, Xiong Wen David

2016-10-20

Lithium-sulfur batteries show advantages for next-generation electrical energy storage due to their high energy density and cost effectiveness. Enhancing the conductivity of the sulfur cathode and moderating the dissolution of lithium polysulfides are two key factors for the success of lithium-sulfur batteries. Here we report a sulfur host that overcomes both obstacles at once. With inherent metallic conductivity and strong adsorption capability for lithium-polysulfides, titanium monoxide@carbon hollow nanospheres can not only generate sufficient electrical contact to the insulating sulfur for high capacity, but also effectively confine lithium-polysulfides for prolonged cycle life. Additionally, the designed composite cathode further maximizes the lithium-polysulfide restriction capability by using the polar shells to prevent their outward diffusion, which avoids the need for chemically bonding all lithium-polysulfides on the surfaces of polar particles.

Pyrrole as a promising electrolyte additive to trap polysulfides for lithium-sulfur batteries

NASA Astrophysics Data System (ADS)

Yang, Wu; Yang, Wang; Song, Ailing; Gao, Lijun; Sun, Gang; Shao, Guangjie

2017-04-01

Lithium-sulfur batteries are a promising energy storage devices beyond conventional lithium ion batteries. However, the "shuttle effect" of soluble polysulfides is a major barrier between electrodes, resulting in rapid capacity fading. To address above issue, pyrrole has been investigated as an electrolyte additive to trap polysulfides. When pyrrole is added into electrolyte, a surface protective layer of polypyrrole can be formed on the sulfur cathode, which not only acts as a conductive agent to provide an effective electron conduction path but also acts as an absorbing agent and barrier layer suppressing the diffusion of polysulfide intermediates. The results demonstrate that an appropriate amount of pyrrole added into the electrolyte leads to excellent cycling stability and rate capability. Apparently, pyrrole is an effective additive for the entrapment of polysulfides of lithium-sulfur batteries.

A sulfur host based on titanium monoxide@carbon hollow spheres for advanced lithium-sulfur batteries

NASA Astrophysics Data System (ADS)

Li, Zhen; Zhang, Jintao; Guan, Buyuan; Wang, Da; Liu, Li-Min; Lou, Xiong Wen (David)

2016-10-01

Lithium-sulfur batteries show advantages for next-generation electrical energy storage due to their high energy density and cost effectiveness. Enhancing the conductivity of the sulfur cathode and moderating the dissolution of lithium polysulfides are two key factors for the success of lithium-sulfur batteries. Here we report a sulfur host that overcomes both obstacles at once. With inherent metallic conductivity and strong adsorption capability for lithium-polysulfides, titanium monoxide@carbon hollow nanospheres can not only generate sufficient electrical contact to the insulating sulfur for high capacity, but also effectively confine lithium-polysulfides for prolonged cycle life. Additionally, the designed composite cathode further maximizes the lithium-polysulfide restriction capability by using the polar shells to prevent their outward diffusion, which avoids the need for chemically bonding all lithium-polysulfides on the surfaces of polar particles.

Separator for lithium-sulfur battery based on polymer blend membrane

NASA Astrophysics Data System (ADS)

Freitag, Anne; Stamm, Manfred; Ionov, Leonid

2017-09-01

In this work we report a novel way of reducing the polysulfide shuttle in lithium-sulfur batteries by a new separator material. Polyvinylsulfate potassium salt (PVSK) as polymeric additive is introduced into a polyvinylidene fluoride-hexafluoropropylene (PVdF-HFP) matrix membrane to improve the battery performance. PVSK is expected to lower the polysulfide mobility due to interaction with the sulfonic group. PVdF-HFP/PVSK blend membranes are prepared and an UV/Vis polysulfide diffusion test clearly demonstrates the positive effect of PVSK. Electrochemical testing reveals a significant improvement of cycling stability up to more than 200 cycles. In addition, the effect of separator porosity to the polysulfide shuttle is investigated with PVdF-HFP membranes of different porosity. A simple polysulfide diffusion test and potentiostatic charge/discharge cycling clearly demonstrate that low separator porosity is favorable in a lithium-sulfur cell.

A sulfur host based on titanium monoxide@carbon hollow spheres for advanced lithium–sulfur batteries

PubMed Central

Li, Zhen; Zhang, Jintao; Guan, Buyuan; Wang, Da; Liu, Li-Min; Lou, Xiong Wen (David)

2016-01-01

Lithium–sulfur batteries show advantages for next-generation electrical energy storage due to their high energy density and cost effectiveness. Enhancing the conductivity of the sulfur cathode and moderating the dissolution of lithium polysulfides are two key factors for the success of lithium–sulfur batteries. Here we report a sulfur host that overcomes both obstacles at once. With inherent metallic conductivity and strong adsorption capability for lithium-polysulfides, titanium monoxide@carbon hollow nanospheres can not only generate sufficient electrical contact to the insulating sulfur for high capacity, but also effectively confine lithium-polysulfides for prolonged cycle life. Additionally, the designed composite cathode further maximizes the lithium-polysulfide restriction capability by using the polar shells to prevent their outward diffusion, which avoids the need for chemically bonding all lithium-polysulfides on the surfaces of polar particles. PMID:27762261

Reduction mechanism of sulfur in lithium-sulfur battery: From elemental sulfur to polysulfide

DOE PAGES

Zheng, Dong; Yang, Xuran; Zhang, Xiaoqing; ...

2015-10-30

In this study, the polysulfide ions formed during the first reduction wave of sulfur in Li–S battery were determined through both in-situ and ex-situ derivatization of polysulfides. By comparing the cyclic voltammetric results with and without the derivatization reagent (methyl triflate) as well as the in-situ and ex-situ derivatization results under potentiostatic condition, in-situ derivatization was found to be more appropriate than its ex-situ counterpart, since subsequent fast chemical reactions between the polysulfides and sulfur may occur during the timeframe of ex-situ procedures. It was found that the major polysulfide ions formed at the first reduction wave of elemental sulfurmore » were the S 4 2– and S 5 2– species, while the widely accepted reduction products of S 8 2– and S 6 2– for the first reduction wave were in low abundance.« less

A three-dimensional cathode matrix with bi-confinement effect of polysulfide for lithium-sulfur battery

NASA Astrophysics Data System (ADS)

Song, Ren-Sheng; Wang, Bo; Ruan, Ting-Ting; Wang, Lei; Luo, Hao; Wang, Fei; Gao, Tian-Tian; Wang, Dian-Long

2018-01-01

Soluble polysulfide shuttling is still the main cause of restricting the development of lithium-sulfur (Li-S) battery. Here, we propose a novel three-dimensional reduced graphene oxide@sulfur/nitrogen-doped porous carbon polyhedron/carbon nanotubes (rGO@S/NCP/CNTs) composite with bi-confinement effect of polysulfide as an effective cathode material. In rGO@S/NCP/CNTs, NCP provides physical confinement for sulfur and soluble polysulfide by its abundant micropores and mesopores, while oxygen functional groups of rGO provide strong chemical confinement to soluble polysulfide. Additionally, CNTs with one-dimensional conductivity enable facile transport of electrons. Therefore, the resulting rGO@S/NCP/CNTs composite shows an obvious enhancement in cycling performance for Li-S battery, and reversible capacities up to 738 mAh g-1 and 660 mAh g-1 over 100 and 200 cycles are remained at 0.2 C rate.

Ferrocene-Promoted Long-Cycle Lithium-Sulfur Batteries.

PubMed

Mi, Yingying; Liu, Wen; Yang, Ke R; Jiang, Jianbing; Fan, Qi; Weng, Zhe; Zhong, Yiren; Wu, Zishan; Brudvig, Gary W; Batista, Victor S; Zhou, Henghui; Wang, Hailiang

2016-11-14

Confining lithium polysulfide intermediates is one of the most effective ways to alleviate the capacity fade of sulfur-cathode materials in lithium-sulfur (Li-S) batteries. To develop long-cycle Li-S batteries, there is an urgent need for material structures with effective polysulfide binding capability and well-defined surface sites; thereby improving cycling stability and allowing study of molecular-level interactions. This challenge was addressed by introducing an organometallic molecular compound, ferrocene, as a new polysulfide-confining agent. With ferrocene molecules covalently anchored on graphene oxide, sulfur electrode materials with capacity decay as low as 0.014 % per cycle were realized, among the best of cycling stabilities reported to date. With combined spectroscopic studies and theoretical calculations, it was determined that effective polysulfide binding originates from favorable cation-π interactions between Li + of lithium polysulfides and the negatively charged cyclopentadienyl ligands of ferrocene. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Harmony of computational quantum chemistry and experimental chemistry: Comprehensive DFT studies, microsynthesis, and characterization of mustard gas polysulfide analogues

NASA Astrophysics Data System (ADS)

Saeidian, Hamid; Faraz, Sajjad Mousavi; Mirjafary, Zohreh; Babri, Mehran

2018-05-01

After microsynthesis, structures of mustard gas polysulfide analogues were characterized using electron impact (EI) mass spectrometry. General EI fragmentation pathways for such compounds are proposed. The structure of sulfur mustard (HD) and its two other polysulfide analogues have been examined through B3LYP/6-311++G(2d, 2p) calculations. Geometrical analysis of HD shows that the calculated bond distances are satisfactorily comparable with experimental results. Calculated NMR chemical shifts for HD also were compared with experimental data, indicating good agreement both for 1H and 13C atoms. The vibrational frequencies of HD and polysulfide analogues have been precisely assigned. At the end, based on visual inspection of lowest unoccupied molecular orbitals and the relative difference in the total energies of their episulfonium ions, relative reactivity of HD and its polysulfide analogues were investigated.

Mercury Methylation by Desulfovibrio desulfuricans ND132 in the Presence of Polysulfides

PubMed Central

Jay, Jenny Ayla; Murray, Karen J.; Gilmour, Cynthia C.; Mason, Robert P.; Morel, François M. M.; Roberts, A. Lynn; Hemond, Harold F.

2002-01-01

The extracellular speciation of mercury may control bacterial uptake and methylation. Mercury-polysulfide complexes have recently been shown to be prevalent in sulfidic waters containing zero-valent sulfur. Despite substantial increases in total dissolved mercury concentration, methylation rates in cultures of Desulfovibrio desulfuricans ND132 equilibrated with cinnabar did not increase in the presence of polysulfides, as expected due to the large size and charged nature of most of the complexes. In natural waters not at saturation with cinnabar, mercury-polysulfide complexes would be expected to shift the speciation of mercury from HgS0(aq) toward charged complexes, thereby decreasing methylation rates. PMID:12406773

Chemical Immobilization Effect on Lithium Polysulfides for Lithium-Sulfur Batteries.

PubMed

Li, Caixia; Xi, Zhucong; Guo, Dexiang; Chen, Xiangju; Yin, Longwei

2018-01-01

Despite great progress in lithium-sulfur batteries (LSBs), great obstacles still exist to achieve high loading content of sulfur and avoid the loss of active materials due to the dissolution of the intermediate polysulfide products in the electrolyte. Relationships between the intrinsic properties of nanostructured hosts and electrochemical performance of LSBs, especially, the chemical interaction effects on immobilizing polysulfides for LSB cathodes, are discussed in this Review. Moreover, the principle of rational microstructure design for LSB cathode materials with strong chemical interaction adsorbent effects on polysulfides, such as metallic compounds, metal particles, organic polymers, and heteroatom-doped carbon, is mainly described. According to the chemical immobilizing mechanism of polysulfide on LSB cathodes, three kinds of chemical immobilizing effects, including the strong chemical affinity between polar host and polar polysulfides, the chemical bonding effect between sulfur and the special function groups/atoms, and the catalytic effect on electrochemical reaction kinetics, are thoroughly reviewed. To improve the electrochemical performance and long cycling life-cycle stability of LSBs, possible solutions and strategies with respect to the rational design of the microstructure of LSB cathodes are comprehensively analyzed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Polysulfides capture-copper additive for long cycle life lithium sulfur batteries

DOE PAGES

Jia, Lei; Wu, Tianpin; Lu, Jun; ...

2016-10-18

Copper powder was introduced into the lithium sulfur battery system to capture intermediate polysulfides and Cu xS (x = 1 or 2) species was generated depending on the chain length of polysulfides. This phenomenon was verified by X-ray absorption near edge structure technique. The results indicated that copper can be oxidized to CuS by Li 2S x (x ≥ 6), and a mixture of Cu 2S and CuS was obtained when x ranges from 3 to 6. While Cu 2S is eventually formed in the presence of Li 2S 3. After several cycles activation, the polysulfide-shuttle effect and self-discharge phenomenonmore » which hinder the application of lithium sulfur batteries are found nearly eliminated Further experiments demonstrated that in the case of Cu 2S generation, a high specific sulfur capacity of 1300 mAh g –1 could be delivered, corresponding to 77.6% sulfur utilization, while the Coulombic efficiency approximates around 100%. As a result, self-discharge experiment further demonstrated that polysulfides almost disappear in the electrolyte, which verified the polysulfide-capture capability of copper.« less

[Risk assessment of rescue helicopter or ambulance transport of patients ingesting hazardous volatile materials].

PubMed

Takegawa, Ryosuke; Ohnishi, Mitsuo; Hirose, Tomoya; Hatano, Yayoi; Imada, Yuko; Endo, Yoko; Shimazu, Takeshi

2016-03-01

In cases of transport by rescue helicopter or ambulance of patients having ingested hazardous substances, medical personnel may be at a certain risk of inhaling the substances. However, few reports have addressed such risk of causing secondary casualties. This simulation study aimed to assess the risk of inhalation of hydrogen sulfide and chlo-opicrin in the cabin of a helicopter or an ambulance transporting a patient who has ingested calcium polysulfide or chloropicrin, which were previously reported to cause secondary casualties. Concentrations of hydrogen sulfide and chloropicrin were assessed on the following as-umptions :The patient ingested 100 mL of the causative or original chemical. All chemical substances reacted with the gastric juice or were thoroughly vomited and evaporated uniformly within the cabin space of the helicopter or ambulance. Environmental conditions were 20 *degrees at 1 atmosphere of pres-ure in a 5 m3 cabin volume in the helicopter and a 13.5 m3 cabin volume in the ambulance. In the case of calcium polysulfide ingestion which produced hydrogen sulfide, its concen-ration reached 774 ppm in the helicopter and 287 ppm in the ambulance. For chloropicrin ingestion, the concentrations were 4,824 ppm and 1,787 ppm, respectively. The simulated concentration of hydrogen sulfide was more than 500 ppm in the heli-opter, which may lead to respiratory paralysis and death. The simulated concentration of chloropicrin was more than 300 ppm, which has a risk of death within 10 minutes. Currently, as far as Japanese laws are concerned, there are no restrictions requiring pretransport assessment or setting criteria for transporting patients who might have ingested hazardous substances that could cause secondary casu-lties when vomited. When patients who might have ingested hazardous chemicals are transported, it is important to recognize the risk of causing secondary casualties by vomiting the chemicals.

Zero VOC, Coal Tar Free Splash Zone Coating (SZC)

DTIC Science & Technology

2010-12-01

polymer became commercially available in 1943, thirteen years after the Thiokol Corporation developed and marketed a millable gum polysulfide known...overall solvent resistance properties as the millable gum polysulfides. However, the liquid polysulfides have the advantage of being room temperature...amine to form a covalent sulfur-carbon bond. The tertiary amine is regenerated and is then available to react with another oxirane group. These

Quantitative and Qualitative Determination of Polysulfide Species in the Electrolyte of a Lithium-Sulfur Battery using HPLC ESI/MS with One-Step Derivatization

DOE PAGES

Zheng, Dong; Qu, Deyu; Yang, Xiao-Qing; ...

2015-01-29

The polysulfide species dissolved in aprotic solvents can be separated and analyzed by reverse phase (RP) high performance liquid chromatography (HPLC) in tandem with electrospray-mass spectroscopy. The relative distribution of polysulfide species in the electrolyte recovered from Li-S batteries is quantitatively and reliably determined for the first time.

Quantitative and Qualitative Determination of Polysulfide Species in the Electrolyte of a Lithium-Sulfur Battery using HPLC ESI/MS with One-Step Derivatization

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

Zheng, Dong; Qu, Deyu; Yang, Xiao-Qing

The polysulfide species dissolved in aprotic solvents can be separated and analyzed by reverse phase (RP) high performance liquid chromatography (HPLC) in tandem with electrospray-mass spectroscopy. The relative distribution of polysulfide species in the electrolyte recovered from Li-S batteries is quantitatively and reliably determined for the first time.

Polysulfide Speciation in the Bulk Electrolyte of a Lithium Sulfur Battery

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

McBrayer, Josefine D.; Beechem, Thomas E.; Perdue, Brian R.

In situ Raman microscopy was used to study polysulfide speciation in the bulk ether electrolyte during the discharge and charge of a Li-S electrochemical cell to assess the complex interplay between chemical and electrochemical reactions in solution. During discharge, long chain polysulfides and the S 3 - radical appear in the electrolyte at 2.4 V indicating a rapid equilibrium of the dissociation reaction to form S 3 -. When charging, however, an increase in the concentration of all polysulfide species was observed. This highlights the importance of the electrolyte to sulfur ratio and suggests a loss in the useful sulfurmore » inventory from the cathode to the electrolyte.« less

Polysulfide Speciation in the Bulk Electrolyte of a Lithium Sulfur Battery

DOE PAGES

McBrayer, Josefine D.; Beechem, Thomas E.; Perdue, Brian R.; ...

2018-03-23

In situ Raman microscopy was used to study polysulfide speciation in the bulk ether electrolyte during the discharge and charge of a Li-S electrochemical cell to assess the complex interplay between chemical and electrochemical reactions in solution. During discharge, long chain polysulfides and the S 3 - radical appear in the electrolyte at 2.4 V indicating a rapid equilibrium of the dissociation reaction to form S 3 -. When charging, however, an increase in the concentration of all polysulfide species was observed. This highlights the importance of the electrolyte to sulfur ratio and suggests a loss in the useful sulfurmore » inventory from the cathode to the electrolyte.« less

A highly efficient polysulfide mediator for lithium-sulfur batteries

NASA Astrophysics Data System (ADS)

Liang, Xiao; Hart, Connor; Pang, Quan; Garsuch, Arnd; Weiss, Thomas; Nazar, Linda F.

2015-01-01

The lithium-sulfur battery is receiving intense interest because its theoretical energy density exceeds that of lithium-ion batteries at much lower cost, but practical applications are still hindered by capacity decay caused by the polysulfide shuttle. Here we report a strategy to entrap polysulfides in the cathode that relies on a chemical process, whereby a host—manganese dioxide nanosheets serve as the prototype—reacts with initially formed lithium polysulfides to form surface-bound intermediates. These function as a redox shuttle to catenate and bind ‘higher’ polysulfides, and convert them on reduction to insoluble lithium sulfide via disproportionation. The sulfur/manganese dioxide nanosheet composite with 75 wt% sulfur exhibits a reversible capacity of 1,300 mA h g-1 at moderate rates and a fade rate over 2,000 cycles of 0.036%/cycle, among the best reported to date. We furthermore show that this mechanism extends to graphene oxide and suggest it can be employed more widely.

Separator Decoration with Cobalt/Nitrogen Codoped Carbon for Highly Efficient Polysulfide Confinement in Lithium-Sulfur Batteries.

PubMed

Hu, Wen; Hirota, Yuichiro; Zhu, Yexin; Yoshida, Nao; Miyamoto, Manabu; Zheng, Tao; Nishiyama, Norikazu

2017-09-22

A macro-/mesoporous Co-N-C-decorated separator is proposed to confine and reutilize migrating polysulfides. Endowed with a desirable structure and synchronous lithio- and sulfiphilic chemistry, the macro-/mesoporous Co-N-C interface manipulates large polysulfide adsorption uptake, enabling good polysulfide adsorption kinetics, reversible electrocatalysis toward redox of anchored polysulfides, and facile charge transport. It significantly boosts the performance of a simple 70 wt % S/MWCNTs (MWCNTs=multi-walled carbon nanotubes) cathode, achieving high initial capacities (e.g., 1406 mAh g -1 at 0.2C, 1203 mAh g -1 at 1C), nearly 100 % Coulombic efficiencies, and high reversible capacities after cycle tests (e.g., 828.4 mAh g -1 at 1C after 100 cycles) at both low and high current rates. These results demonstrate that decorating separator with macro-/mesoporous Co-N-C paves a feasible way for developing advanced Li-S batteries. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fluorescent Probes and Selective Inhibitors for Biological Studies of Hydrogen Sulfide- and Polysulfide-Mediated Signaling.

PubMed

Takano, Yoko; Echizen, Honami; Hanaoka, Kenjiro

2017-10-01

Hydrogen sulfide (H 2 S) plays roles in many physiological processes, including relaxation of vascular smooth muscles, mediation of neurotransmission, inhibition of insulin signaling, and regulation of inflammation. Also, hydropersulfide (R-S-SH) and polysulfide (-S-S n -S-) have recently been identified as reactive sulfur species (RSS) that regulate the bioactivities of multiple proteins via S-sulfhydration of cysteine residues (protein Cys-SSH) and show cytoprotection. Chemical tools such as fluorescent probes and selective inhibitors are needed to establish in detail the physiological roles of H 2 S and polysulfide. Recent Advances: Although many fluorescent probes for H 2 S are available, fluorescent probes for hydropersulfide and polysulfide have only recently been developed and used to detect these sulfur species in living cells. In this review, we summarize recent progress in developing chemical tools for the study of H 2 S, hydropersulfide, and polysulfide, covering fluorescent probes based on various design strategies and selective inhibitors of H 2 S- and polysulfide-producing enzymes (cystathionine γ-lyase, cystathionine β-synthase, and 3-mercaptopyruvate sulfurtransferase), and we summarize their applications in biological studies. Despite recent progress, the precise biological functions of H 2 S, hydropersulfide, and polysulfide remain to be fully established. Fluorescent probes and selective inhibitors are effective chemical tools to study the physiological roles of these sulfur molecules in living cells and tissues. Therefore, further development of a broad range of practical fluorescent probes and selective inhibitors as tools for studies of RSS biology is currently attracting great interest. Antioxid. Redox Signal. 27, 669-683.

Evaluating silicene as a potential cathode host to immobilize polysulfides in lithium–sulfur batteries

DOE PAGES

Liu, Zhixiao; Balbuena, Perla B.; Mukherjee, Partha P.

2016-05-27

The internal shuttle effect caused by polysulfides dissolution and migration negatively impacts lithium–sulfur battery performance. In this paper, a mesoscale simulation strategy, which involves atomistic calculation and coarse-grained molecular modeling, is employed to evaluate silicene as a potential cathode host material to immobilize polysulfides. Adsorption energies of insoluble polysulfides (Li 2S x with x =1, 2) and soluble polysulfide Li 2S 4 on pristine and doped silicene sheets are calculated. Results show that the adsorption is thermodynamically favorable and N-doped silicene is helpful in trapping intermediate discharge products, Li 2S 2 and Li 2S 4. The dissociation and reduction ofmore » long-chain polysulfides to short-chain polysulfides are observed. Electronic structure analysis shows that Li 2S x molecules interact with silicene via strong chemical bonds. The atomistic structure evolution of Li 2S layer formation on silicene is also investigated in this study. It is found that Li 2S (110) layer forms first, and then, it is converted to Li 2S (111) layer by introducing more Li 2S molecules to the substrate. Li 2S (111)/silicene interfacial structure is thermodynamically stable, and the interaction is dominated by Li–Si bonds. A coarse-grained model is developed to study and compare the growth of Li 2S on silicene and graphene. Lastly, Li 2S-induced surface coverage is faster on silicene than on graphene, which indicates that a silicene-based cathode host will experience more acute surface passivation, which will adversely affect cathode performance.« less

Toward a Molecular Understanding of Energetics in Li–S Batteries Using Nonaqueous Electrolytes: A High-Level Quantum Chemical Study

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

Assary, Rajeev S.; Curtiss, Larry A.; Moore, Jeffrey S.

2014-06-05

The Li-S battery (secondary cell or redox flow) technology is a promising future alternative to the present lithium intercalation-based energy storage and, therefore, a molecular level understanding of the chemical processes and properties such as stability of intermediates, reactivity of polysulfides and reactivity towards the non-aqueous electrolytes in the Li-S batteries is of great interest. In this paper, quantum chemical methods (G4MP2, MP2, and B3LYP) were utilized to compute reduction potentials of lithium polysulfides and polysulfide molecular clusters, energetics of disproportionation and association reactions of likely intermediates, and their reactions with ether-based electrolytes. Based on the computed reaction energetics inmore » solution, a probable mechanism during the discharge process for polysulfide anions and lithium polysulfides in solution is proposed and likely intermediates such as S42-,S32-, S22-, and S31- radical were identified. Additionally, the stability and reactivity of propylene carbonate and tetraglyme solvent molecules were assessed against the above-mentioned intermediates and other reactive species by computing the reaction energetics required to initiate the solvent decomposition reactions in solution. Calculations suggest that the propylene carbonate molecule is unstable against the polysulfide anions such as S22-, S32-, and S42- (ΔH† < 0.8 eV) and highly reactive towards Li2S2 and Li2S3. Even though the tetraglyme solvent molecule exhibits increased stability towards polysulfide anions compared to propylene carbonate, this molecule too is vulnerable to nucleophilic attack from Li2S2 and Li2S3 species in solutions. Hence, a long- term stability of the ether molecules is unlikely if high concentration of these reactive intermediates present in the Li-S energy storage systems.« less

Fluorescent Probes and Selective Inhibitors for Biological Studies of Hydrogen Sulfide- and Polysulfide-Mediated Signaling

PubMed Central

Takano, Yoko; Echizen, Honami

2017-01-01

Abstract Significance: Hydrogen sulfide (H2S) plays roles in many physiological processes, including relaxation of vascular smooth muscles, mediation of neurotransmission, inhibition of insulin signaling, and regulation of inflammation. Also, hydropersulfide (R−S−SH) and polysulfide (−S−Sn−S−) have recently been identified as reactive sulfur species (RSS) that regulate the bioactivities of multiple proteins via S-sulfhydration of cysteine residues (protein Cys−SSH) and show cytoprotection. Chemical tools such as fluorescent probes and selective inhibitors are needed to establish in detail the physiological roles of H2S and polysulfide. Recent Advances: Although many fluorescent probes for H2S are available, fluorescent probes for hydropersulfide and polysulfide have only recently been developed and used to detect these sulfur species in living cells. Critical Issues: In this review, we summarize recent progress in developing chemical tools for the study of H2S, hydropersulfide, and polysulfide, covering fluorescent probes based on various design strategies and selective inhibitors of H2S- and polysulfide-producing enzymes (cystathionine γ-lyase, cystathionine β-synthase, and 3-mercaptopyruvate sulfurtransferase), and we summarize their applications in biological studies. Future Directions: Despite recent progress, the precise biological functions of H2S, hydropersulfide, and polysulfide remain to be fully established. Fluorescent probes and selective inhibitors are effective chemical tools to study the physiological roles of these sulfur molecules in living cells and tissues. Therefore, further development of a broad range of practical fluorescent probes and selective inhibitors as tools for studies of RSS biology is currently attracting great interest. Antioxid. Redox Signal. 27, 669–683. PMID:28443673

Reaction between Lithium Anode and Polysulfide Ions in a Lithium-Sulfur Battery

DOE PAGES

Zheng, Dong; Yang, Xiao-Qing; Qu, Deyang

2016-08-18

Here, the reaction between polysulfides and a lithium anode in a Li–S battery was examined using HPLC. The results demonstrated that the polysulfide species with six sulfur atoms or more were reactive with regard to lithium metal. Although the reaction can be greatly inhibited by the addition of LiNO 3 in the electrolyte, LiNO 3 cannot form a stable protection layer on the Li anode to prevent the reaction during storage.

Reaction between Lithium Anode and Polysulfide Ions in a Lithium-Sulfur Battery

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

Zheng, Dong; Yang, Xiao-Qing; Qu, Deyang

Here, the reaction between polysulfides and a lithium anode in a Li–S battery was examined using HPLC. The results demonstrated that the polysulfide species with six sulfur atoms or more were reactive with regard to lithium metal. Although the reaction can be greatly inhibited by the addition of LiNO 3 in the electrolyte, LiNO 3 cannot form a stable protection layer on the Li anode to prevent the reaction during storage.

Polysulfide Anchoring Mechanism Revealed by Atomic Layer Deposition of V2O5 and Sulfur-Filled Carbon Nanotubes for Lithium-Sulfur Batteries.

PubMed

Carter, Rachel; Oakes, Landon; Muralidharan, Nitin; Cohn, Adam P; Douglas, Anna; Pint, Cary L

2017-03-01

Despite the promise of surface engineering to address the challenge of polysulfide shuttling in sulfur-carbon composite cathodes, melt infiltration techniques limit mechanistic studies correlating engineered surfaces and polysulfide anchoring. Here, we present a controlled experimental demonstration of polysulfide anchoring using vapor phase isothermal processing to fill the interior of carbon nanotubes (CNTs) after assembly into binder-free electrodes and atomic layer deposition (ALD) coating of polar V 2 O 5 anchoring layers on the CNT surfaces. The ultrathin submonolayer V 2 O 5 coating on the CNT exterior surface balances the adverse effect of polysulfide shuttling with the necessity for high sulfur utilization due to binding sites near the conductive CNT surface. The sulfur loaded into the CNT interior provides a spatially separated control volume enabling high sulfur loading with direct sulfur-CNT electrical contact for efficient sulfur conversion. By controlling ALD coating thickness, high initial discharge capacity of 1209 mAh/g S at 0.1 C and exceptional cycling at 0.2 C with 87% capacity retention after 100 cycles and 73% at 450 cycles is achieved and correlated to an optimal V 2 O 5 anchoring layer thickness. This provides experimental evidence that surface engineering approaches can be effective to overcome polysulfide shuttling by controlled design of molecular-scale building blocks for efficient binder free lithium sulfur battery cathodes.

Effective Trapping of Lithium Polysulfides Using a Functionalized Carbon Nanotube-Coated Separator for Lithium-Sulfur Cells with Enhanced Cycling Stability.

PubMed

Ponraj, Rubha; Kannan, Aravindaraj G; Ahn, Jun Hwan; Lee, Jae Hee; Kang, Joonhee; Han, Byungchan; Kim, Dong-Won

2017-11-08

The critical issues that hinder the practical applications of lithium-sulfur batteries, such as dissolution and migration of lithium polysulfides, poor electronic conductivity of sulfur and its discharge products, and low loading of sulfur, have been addressed by designing a functional separator modified using hydroxyl-functionalized carbon nanotubes (CNTOH). Density functional theory calculations and experimental results demonstrate that the hydroxyl groups in the CNTOH provoked strong interaction with lithium polysulfides and resulted in effective trapping of lithium polysulfides within the sulfur cathode side. The reduction in migration of lithium polysulfides to the lithium anode resulted in enhanced stability of the lithium electrode. The conductive nature of CNTOH also aided to efficiently reutilize the adsorbed reaction intermediates for subsequent cycling. As a result, the lithium-sulfur cell assembled with a functional separator exhibited a high initial discharge capacity of 1056 mAh g -1 (corresponding to an areal capacity of 3.2 mAh cm -2 ) with a capacity fading rate of 0.11% per cycle over 400 cycles at 0.5 C rate.

A natural carbonized leaf as polysulfide diffusion inhibitor for high-performance lithium-sulfur battery cells.

PubMed

Chung, Sheng-Heng; Manthiram, Arumugam

2014-06-01

Attracted by the unique tissue and functions of leaves, a natural carbonized leaf (CL) is presented as a polysulfide diffusion inhibitor in lithium-sulfur (Li-S) batteries. The CL that is covered on the pure sulfur cathode effectively suppresses the polysulfide shuttling mechanism and enables the use of pure sulfur as the cathode. A low charge resistance and a high discharge capacity of 1320 mA h g(-1) arise from the improved cell conductivity due to the innately integral conductive carbon network of the CL. The unique microstructure of CL leads to a high discharge/charge efficiency of >98 %, low capacity fade of 0.18 % per cycle, and good long-term cyclability over 150 cycles. The structural gradient and the micro/mesoporous adsorption sites of CL effectively intercept/trap the migrating polysulfides and facilitate their reutilization. The green CL polysulfide diffusion inhibitor thus offers a viable approach for developing high-performance lithium-sulfur batteries. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effective Dual Polysulfide Rejection by a Tannic Acid/FeIII Complex-Coated Separator in Lithium-Sulfur Batteries.

PubMed

Zhang, Hong; Lin, Chuner; Hu, Xuanhe; Zhu, Baoku; Yu, Dingshan

2018-04-18

The solubility behaviour of polysulfides in electrolyte solutions is a major bottleneck prior to the practical application of the lithium-sulfur battery. To address this issue, we fabricate a tannic acid/Fe III complex-coated polypropylene (PP) separator (TA/Fe III -PP separator) via a simple, fast, and green method. Benefiting from dual-confinement effects based on Lewis acid-base interactions between Fe III and polysulfides as well as the dipole-dipole interactions between rich phenol groups and polysulfides, the migration of polysulfides is effectively suppressed. Meanwhile, the porous structure of the PP separator is not destroyed by an additional coating layer. Thus, the TA/Fe III -PP separator can retain rapid lithium ion transport, eventually leading to a significant improvement in both the discharge capacity and rate performance of the corresponding lithium-sulfur cells. The cell with the TA/Fe III -PP separator presents a low capacity fade of 0.06% per cycle over 1000 cycles at 2.0 C, along with a high Coulombic efficiency of >97% over 300 cycles at 0.5 C. With respect to the one with the bare PP separator, the cell with the TA/Fe III -PP separator exhibits a 1.7-fold increase in the discharge capacity at 3.0 C. The proposed simple and economical approach shows great potential in constructing advanced separators to retard the shuttle effect of polysulfides for lithium-sulfur batteries.

Harvesting polysulfides by sealing the sulfur electrode in a composite ion-selective net

NASA Astrophysics Data System (ADS)

Chen, Yazhou; Li, Zhong; Li, Xuekui; Zeng, Danli; Xu, Guodong; Zhang, Yunfeng; Sun, Yubao; Ke, Hanzhong; Cheng, Hansong

2017-11-01

A cathode was prepared by sealing a carbon supported sulfur electrode inside a composite ion-selective net made of carbon, binder and lithiated ionomer to restrict shuttling of polysulfide anionic species. As a result, the soluble polysulfide anions become unable to escape from the composite ion-selective films due to the electrostatic repulsion between the immobilized single ion conducting ionomers and the polysulfides with no dead angles. Experimentally, lithiated 4,4‧-difluoro bis(benzene sulfonyl)imide and PEG200 were copolymerized to form a polyether based single ion conducting polymer. The ionic conductivity of the blend film made of ionomer and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) at a mass ratio of 1:1 is 0.57 mS cm-1 at room temperature. The battery capacity with the sealed sulfur electrode is 1412 mAh g-1 at 0.5 C, 1041 mAh g-1 at 1.0 C, 873 mAh g-1 at 2.0 C and 614 mAh g-1 at 5.0 C, significantly better than the results with lithiated Nafion especially at high C rates. In addition, a long cycling test at 2 C for 500 cycles gives rise to a stable capacity of 800 mAh g-1. The intrinsic electrostatic repulsion between polysulfide anions and the negatively charged electrolyte film, together with the overall sealed electrode configuration, is responsible for blocking the shuttling of polysulfides effectively.

Molecular Structural Characteristics of Polysaccharide Fractions from Canarium album (Lour.) Raeusch and Their Antioxidant Activities.

PubMed

Zeng, Hongliang; Miao, Song; Zheng, Baodong; Lin, Shan; Jian, Yeye; Chen, Shen; Zhang, Yi

2015-11-01

The objective of this study was to investigate the multiple relations between the preliminary molecular structural characteristics and antioxidant activities of polysaccharides from Canarium album (Lour.) Raeusch (CPS). Three polysaccharide fractions, CPS1, CPS2, and CPS3, were isolated from CPS by column chromatography. CPS1 and CPS3 were mainly composed of neutral polysaccharides linked by α- and β-glycosidic linkages while CPS2 was pectin polysaccharides mainly linked by β-glycosidic linkages. According to the SEC-MALLS-RI system, the molecular weight of CPS1 was greater compared to CPS2 and CPS3, and the molecular weight and radius of CPS did not display positive correlation. The chain conformation analysis indicated CPS1 and CPS2 were typical highly branched polysaccharides while CPS3 existed as a globular shape in aqueous. Furthermore, the antioxidant activity of CPS2 was better than that of CPS3, while that of CPS1 was the weakest. The antioxidant activities of polysaccharide fractions were affected by their monosaccharide composition, glycosidic linkage, molecular weight, and chain conformation. This functional property was a result of a combination of multiple molecular structural factors. CPS2 was the major antioxidant component of CPS and it could be exploited as a valued antioxidant product. The molecular structural characteristics, antioxidant activities, and structure-function relationships of polysaccharide fractions from Canarium album were first investigated in this study. The results provided background and practical knowledge for the deep-processed products of C. album with high added value. CPS2 was the major antioxidant component of CPS, which could be exploited as a valued antioxidant ingredient in food and pharmaceutical industries. © 2015 Institute of Food Technologists®

A novel strategy for high-stability lithium sulfur batteries by in situ formation of polysulfide adsorptive-blocking layer

NASA Astrophysics Data System (ADS)

Jin, Liming; Li, Gaoran; Liu, Binhong; Li, Zhoupeng; Zheng, Junsheng; Zheng, Jim P.

2017-07-01

Lithium sulfur (Lisbnd S) batteries are one of the most promising energy storage devices owing to their high energy and power density. However, the shuttle effect as a key barrier hinders its practical application by resulting in low coulombic efficiency and poor cycling performance. Herein, a novel design of in situ formed polysulfide adsorptive-blocking layer (PAL) on the cathode surface was developed to tame the polysulfide shuttling and promote the cycling stability for Lisbnd S batteries. The PAL is consisted of La2S3, which is capable to chemically adsorb polysulfide via the strong interaction of Lasbnd S bond and Ssbnd S bond, and build an effective barrier against sulfur escaping. Moreover, the La2S3 is capable to suppress the crystallization of Li2S and promote the ion transfer, which contributes to the reduced internal resistance of batteries. Furthermore, the by-product LiNO3 simultaneously forms a stable anode solid and electrolyte interface to further inhibit the polysulfide shuttle. By this simple and convenient method, the resultant Lisbnd S batteries achieved exceptional cycling stability with an ultralow decay rate of 0.055% since the 10th cycle.

Lightweight Reduced Graphene Oxide@MoS2 Interlayer as Polysulfide Barrier for High-Performance Lithium-Sulfur Batteries.

PubMed

Tan, Lei; Li, Xinhai; Wang, Zhixing; Guo, Huajun; Wang, Jiexi

2018-01-31

The further development of lithium-sulfur (Li-S) batteries is limited by the fact that the soluble polysulfide leads to the shuttle effect, thereby reducing the cycle stability and cycle life of the batteries. To address this issue, here a thin and lightweight (8 μm and 0.24 mg cm -2 ) reduced graphene oxide@MoS 2 (rGO@MoS 2 ) interlayer between the cathode and the commercial separator is developed as a polysulfide barrier. The rGO plays the roles of both a polysulfide physical barrier and an additional current collector, while MoS 2 has a high chemical adsorption for polysulfides. The experiments demonstrate that the Li-S cell constructed with an rGO@MoS 2 -coated separator shows a high reversible capacity of 1122 mAh g -1 at 0.2 C, a low capacity fading rate of 0.116% for 500 cycles at 1 C, and an outstanding rate performance (615 mAh g -1 at 2 C). Such an interlayer is expected to be ideal for lithium-sulfur battery applications because of its excellent electrochemical performance and simple synthesis process.

Molybdenum nitride fibers or tubes via ammonolysis of polysulfide precursor

NASA Astrophysics Data System (ADS)

Wang, Shutao; Zhang, Zude; Zhang, Yange; Qian, Yitai

2004-08-01

Millimeter-sized molybdenum nitride (MoN), in the forms of fiber-like prisms or hollow tubes, has been successfully synthesized via thermal ammonolysis of molybdenum polysulfide precursor. The initial morphology of the precursor is well preserved in the final product. This method could be expanded to preparation of other fiber-like nonmetal ceramics without addition of template. The polysulfide precursor (abbreviated to PS), hydrothermally prepared at 30°C (PS1) or 150°C (PS2), was characterized by various methods for better comprehension of the sulfide-nitride topotactic conversion model.

Sulfur‐Limonene Polysulfide: A Material Synthesized Entirely from Industrial By‐Products and Its Use in Removing Toxic Metals from Water and Soil

PubMed Central

Crockett, Michael P.; Evans, Austin M.; Worthington, Max J. H.; Albuquerque, Inês S.; Slattery, Ashley D.; Gibson, Christopher T.; Campbell, Jonathan A.; Lewis, David A.; Bernardes, Gonçalo J. L.

2015-01-01

Abstract A polysulfide material was synthesized by the direct reaction of sulfur and d‐limonene, by‐products of the petroleum and citrus industries, respectively. The resulting material was processed into functional coatings or molded into solid devices for the removal of palladium and mercury salts from water and soil. The binding of mercury(II) to the sulfur‐limonene polysulfide resulted in a color change. These properties motivate application in next‐generation environmental remediation and mercury sensing. PMID:26481099

Reaction between Lithium Anode and Polysulfide Ions in a Lithium-Sulfur Battery.

PubMed

Zheng, Dong; Yang, Xiao-Qing; Qu, Deyang

2016-09-08

The reaction between polysulfides and a lithium anode in a Li-S battery was examined using HPLC. The results demonstrated that the polysulfide species with six sulfur atoms or more were reactive with regard to lithium metal. Although the reaction can be greatly inhibited by the addition of LiNO3 in the electrolyte, LiNO3 cannot form a stable protection layer on the Li anode to prevent the reaction during storage. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Involvement of Intermediate Sulfur Species in Biological Reduction of Elemental Sulfur under Acidic, Hydrothermal Conditions

PubMed Central

Druschel, Gregory K.

2013-01-01

The thermoacidophile and obligate elemental sulfur (S80)-reducing anaerobe Acidilobus sulfurireducens 18D70 does not associate with bulk solid-phase sulfur during S80-dependent batch culture growth. Cyclic voltammetry indicated the production of hydrogen sulfide (H2S) as well as polysulfides after 1 day of batch growth of the organism at pH 3.0 and 81°C. The production of polysulfide is likely due to the abiotic reaction between S80 and the biologically produced H2S, as evinced by a rapid cessation of polysulfide formation when the growth temperature was decreased, inhibiting the biological production of sulfide. After an additional 5 days of growth, nanoparticulate S80 was detected in the cultivation medium, a result of the hydrolysis of polysulfides in acidic medium. To examine whether soluble polysulfides and/or nanoparticulate S80 can serve as terminal electron acceptors (TEA) supporting the growth of A. sulfurireducens, total sulfide concentration and cell density were monitored in batch cultures with S80 provided as a solid phase in the medium or with S80 sequestered in dialysis tubing. The rates of sulfide production in 7-day-old cultures with S80 sequestered in dialysis tubing with pore sizes of 12 to 14 kDa and 6 to 8 kDa were 55% and 22%, respectively, of that of cultures with S80 provided as a solid phase in the medium. These results indicate that the TEA existed in a range of particle sizes that affected its ability to diffuse through dialysis tubing of different pore sizes. Dynamic light scattering revealed that S80 particles generated through polysulfide rapidly grew in size, a rate which was influenced by the pH of the medium and the presence of organic carbon. Thus, S80 particles formed through abiological hydrolysis of polysulfide under acidic conditions appeared to serve as a growth-promoting TEA for A. sulfurireducens. PMID:23335768

The genetic organization of the capsular polysaccharide biosynthesis region of Actinobacillus pleuropneumoniae serotype 14

PubMed Central

ITO, Hiroya

2015-01-01

The genetic organization of the gene involved in the capsular polysaccharide (CPS) biosynthesis of Actinobacillus pleuropneumoniae serotype 14 has been determined. The DNA region for the CPS biosynthesis of serotype 14 (cps14) comprised 9 open reading frames, designated as cps14AB1B2B3CDEFG genes, encoding Cps14A to Cps14G protein, respectively. Cps14A was similar to CpsA of A. pleuropneumoniae serotypes 1, 4 and 12; the Cps14B1 and Cps14B2 were similar to CpsB of A. pleuropneumoniae serotypes 1, 4 and 12, suggesting that CPS structure of A. pleuropneumoniae serotype 14 would belong to Group I including A. pleuropneumoniae serotypes 1, 4, 12 and 15. Surprisingly, the overall nucleotide sequence, deduced amino acid sequence, and the genetic organization of the cps14 were nearly identical to those of Actinobacillus suis. This study will provide the molecular basic knowledge for development of diagnostics and vaccine of A. pleuropneumoniae serotype 14. PMID:25648373

Three-Dimensional Graphene-Carbon Nanotube-Ni Hierarchical Architecture as a Polysulfide Trap for Lithium-Sulfur Batteries.

PubMed

Gnana Kumar, G; Chung, Sheng-Heng; Raj Kumar, T; Manthiram, Arumugam

2018-06-20

Despite their high energy density and affordable cost compared to lithium-ion (Li-ion) batteries, lithium-sulfur (Li-S) batteries still endure from slow reaction kinetics and capacity loss induced by the insulating sulfur and severe polysulfide diffusion. To address these issues, we report here nickel nanoparticles filled in vertically grown carbon nanotubes (CNTs) on graphene sheets (graphene-CNT-nickel composite (Gr-CNT-Ni)) that are coated onto a polypropylene separator as a polysulfide trap for the construction of high-loading sulfur cathodes. The hierarchical porous framework of Gr-CNT physically entraps and immobilizes the active material sulfur, while the strong chemical interaction with Ni nanoparticles in Gr-CNT-Ni inhibits polysulfide diffusion. The covalently interconnected electron conduction channels and carbon shell-confined metal active sites provide feasible paths for the continual regeneration of active material during the charge-discharge process. Benefitting from these novel morphological and structural features, the Li-S cell with the Gr-CNT-Ni as a polysulfide trap demonstrates high specific capacity and good cycle life. This work provides new avenues for synergistically combining the advantages of hierarchical porous carbon architectures and metal active sites for the development of high-performance cathodes for Li-S batteries.

Modified Separator Performing Dual Physical/Chemical Roles to Inhibit Polysulfide Shuttle Resulting in Ultrastable Li-S Batteries.

PubMed

Abbas, Syed Ali; Ding, Jiang; Wu, Sheng Hui; Fang, Jason; Boopathi, Karunakara Moorthy; Mohapatra, Anisha; Lee, Li Wei; Wang, Pen-Cheng; Chang, Chien-Cheng; Chu, Chih Wei

2017-12-26

In this paper we describe a modified (AEG/CH) coated separator for Li-S batteries in which the shuttling phenomenon of the lithium polysulfides is restrained through two types of interactions: activated expanded graphite (AEG) flakes interacted physically with the lithium polysulfides, while chitosan (CH), used to bind the AEG flakes on the separator, interacted chemically through its abundance of amino and hydroxyl functional groups. Moreover, the AEG flakes facilitated ionic and electronic transfer during the redox reaction. Live H-cell discharging experiments revealed that the modified separator was effective at curbing polysulfide shuttling; moreover, X-ray photoelectron spectroscopy analysis of the cycled separator confirmed the presence of lithium polysulfides in the AEG/CH matrix. Using this dual functional interaction approach, the lifetime of the pure sulfur-based cathode was extended to 3000 cycles at 1C-rate (1C = 1670 mA/g), decreasing the decay rate to 0.021% per cycle, a value that is among the best reported to date. A flexible battery based on this modified separator exhibited stable performance and could turn on multiple light-emitting diodes. Such modified membranes with good mechanical strength, high electronic conductivity, and anti-self-discharging shield appear to be a scalable solution for future high-energy battery systems.

Lithium-sulfur batteries: Making the invisible visible

NASA Astrophysics Data System (ADS)

Johansson, Patrik

2017-06-01

The presence of polysulfides in Li-S batteries significantly affects battery operation, but their presence and reaction mechanisms are not well understood. Now, an operando X-ray diffraction approach is used to directly observe these polysulfides, offering insights on their formation and evolution.

The First Step of Gibberellin Biosynthesis in Pumpkin Is Catalyzed by at Least Two Copalyl Diphosphate Synthases Encoded by Differentially Regulated Genes

PubMed Central

Smith, Maria W.; Yamaguchi, Shinjiro; Ait-Ali, Tahar; Kamiya, Yuji

1998-01-01

The first step in gibberellin biosynthesis is catalyzed by copalyl diphosphate synthase (CPS) and ent-kaurene synthase. We have cloned from pumpkin (Cucurbita maxima L.) two cDNAs, CmCPS1 and CmCPS2, that each encode a CPS. Both recombinant fusion CmCPS proteins were active in vitro. CPS are translocated into plastids and processed by cleavage of transit peptides. For CmCPS1 and CmCPS2, the putative transit peptides cannot exceed the first 99 and 107 amino acids, respectively, because longer N-terminal deletions abolished activity. Levels of both CmCPS transcripts were strictly regulated in an organ-specific and developmental manner. Both transcripts were almost undetectable in leaves and were abundant in petioles. CmCPS1 transcript levels were high in young cotyledons and low in roots. In contrast, CmCPS2 transcripts were undetectable in cotyledons but present at significant levels in roots. In hypocotyls, apices, and petioles, CmCPS1 transcript levels decreased with age much more rapidly than those of CmCPS2. We speculate that CmCPS1 expression is correlated with the early stages of organ development, whereas CmCPS2 expression is correlated with subsequent growth. In contrast, C. maxima ent-kaurene synthase transcripts were detected in every organ at almost constant levels. Thus, ent-kaurene biosynthesis may be regulated through control of CPS expression. PMID:9847116

Garlic oil polysulfides: H2S- and O2-independent prooxidants in buffer and antioxidants in cells

PubMed Central

DeLeon, Eric R.; Gao, Yan; Huang, Evelyn

2016-01-01

The health benefits of garlic and other organosulfur-containing foods are well recognized and have been attributed to both prooxidant and antioxidant activities. The effects of garlic are surprisingly similar to those of hydrogen sulfide (H2S), which is also known to be released from garlic under certain conditions. However, recent evidence suggests that polysulfides, not H2S, may be the actual mediator of physiological signaling. In this study, we monitored formation of H2S and polysulfides from garlic oil in buffer and in human embryonic kidney (HEK) 293 cells with fluorescent dyes, 7-azido-4-methylcoumarin and SSP4, respectively and redox activity with two redox indicators redox-sensitive green fluorescent protein (roGFP) and DCF. Our results show that H2S release from garlic oil in buffer requires other low-molecular-weight thiols, such as cysteine (Cys) or glutathione (GSH), whereas polysulfides are readily detected in garlic oil alone. Administration of garlic oil to cells rapidly increases intracellular polysulfide but has minimal effects on H2S unless Cys or GSH are also present in the extracellular medium. We also observed that garlic oil and diallyltrisulfide (DATS) potently oxidized roGFP in buffer but did not affect DCF. This appears to be a direct polysulfide-mediated oxidation that does not require a reactive oxygen species intermediate. Conversely, when applied to cells, garlic oil became a significant intracellular reductant independent of extracellular Cys or GSH. This suggests that intracellular metabolism and further processing of the sulfur moieties are necessary to confer antioxidant properties to garlic oil in vivo. PMID:27101293

Garlic oil polysulfides: H2S- and O2-independent prooxidants in buffer and antioxidants in cells.

PubMed

DeLeon, Eric R; Gao, Yan; Huang, Evelyn; Olson, Kenneth R

2016-06-01

The health benefits of garlic and other organosulfur-containing foods are well recognized and have been attributed to both prooxidant and antioxidant activities. The effects of garlic are surprisingly similar to those of hydrogen sulfide (H2S), which is also known to be released from garlic under certain conditions. However, recent evidence suggests that polysulfides, not H2S, may be the actual mediator of physiological signaling. In this study, we monitored formation of H2S and polysulfides from garlic oil in buffer and in human embryonic kidney (HEK) 293 cells with fluorescent dyes, 7-azido-4-methylcoumarin and SSP4, respectively and redox activity with two redox indicators redox-sensitive green fluorescent protein (roGFP) and DCF. Our results show that H2S release from garlic oil in buffer requires other low-molecular-weight thiols, such as cysteine (Cys) or glutathione (GSH), whereas polysulfides are readily detected in garlic oil alone. Administration of garlic oil to cells rapidly increases intracellular polysulfide but has minimal effects on H2S unless Cys or GSH are also present in the extracellular medium. We also observed that garlic oil and diallyltrisulfide (DATS) potently oxidized roGFP in buffer but did not affect DCF. This appears to be a direct polysulfide-mediated oxidation that does not require a reactive oxygen species intermediate. Conversely, when applied to cells, garlic oil became a significant intracellular reductant independent of extracellular Cys or GSH. This suggests that intracellular metabolism and further processing of the sulfur moieties are necessary to confer antioxidant properties to garlic oil in vivo. Copyright © 2016 the American Physiological Society.

Useful Ingredients Recovery from Sewage Sludge by using Hydrothermal Reaction

NASA Astrophysics Data System (ADS)

Suzuki, Koichi; Moriyama, Mika; Yamasaki, Yuki; Takahashi, Yui; Inoue, Chihiro

2006-05-01

Hydrothermal treatment of sludge from a sewage treatment plant was conducted to obtain useful ingredients for culture of specific microbes which can reduce polysulfide ion into sulfide ion and/or hydrogen sulfide. Several additives such as acid, base, and oxidizer were added to the hydrothermal reaction of excess sludge to promote the production of useful materials. After hydrothermal treatment, reaction solution and precipitation were qualitatively and quantitatively analyzed and estimated the availability as nutrition in cultural medium. From the results of product analysis, most of organic solid in sewage was basically decomposed by hydrothermal hydrolysis and transformed into oily or water-soluble compounds. Bacterial culture of sulfate-reducing bacteria (SRB) showed the good results in multiplication with medium which was obtained from hydrothermal treatment of sewage sludge with magnesium or calcium hydroxide and hydrogen peroxide.

A composite of hollow carbon nanospheres and sulfur-rich polymers for lithium-sulfur batteries

NASA Astrophysics Data System (ADS)

Zeng, Shao-Zhong; Yao, Yuechao; Zeng, Xierong; He, Qianjun; Zheng, Xianfeng; Chen, Shuangshuang; Tu, Wenxuan; Zou, Jizhao

2017-07-01

Lithium-sulfur batteries are the most promising candidates for future high-energy applications because of the unparalleled capacity of sulfur (1675 mAh g-1). However, lithium-sulfur batteries have limited cycle life and rate capability due to the dissolution of polysulfides and the extremely low electronic conductivity of sulfur. To solve these issues, various porous carbons including hollow carbon nanospheres (HCNs) have been used for improving the conductivity. However, these methods still suffer from polysulfides dissolution/loss owing to their weak physical adsorption to polysulfides. Herein, we introduced a covalent grafting route to composite the HCNs and the vulcanized trithiocyanuric acid (TTCA). The composite exhibits a high loading of the vulcanized TTCA by the HCNs with high surface area and large pore volume, and covalent bonds to sulfur, effectively depressing the dissolution of polysulfides. The first discharge capacity of the composite reaches 1430 mAh g-1 at 0.1 C and 1227 mAh g-1 at 0.2 C.

Chemisorption of polysulfides through redox reactions with organic molecules for lithium-sulfur batteries.

PubMed

Li, Ge; Wang, Xiaolei; Seo, Min Ho; Li, Matthew; Ma, Lu; Yuan, Yifei; Wu, Tianpin; Yu, Aiping; Wang, Shun; Lu, Jun; Chen, Zhongwei

2018-02-16

Lithium-sulfur battery possesses high energy density but suffers from severe capacity fading due to the dissolution of lithium polysulfides. Novel design and mechanisms to encapsulate lithium polysulfides are greatly desired by high-performance lithium-sulfur batteries towards practical applications. Herein, we report a strategy of utilizing anthraquinone, a natural abundant organic molecule, to suppress dissolution and diffusion of polysulfides species through redox reactions during cycling. The keto groups of anthraquinone play a critical role in forming strong Lewis acid-based chemical bonding. This mechanism leads to a long cycling stability of sulfur-based electrodes. With a high sulfur content of ~73%, a low capacity decay of 0.019% per cycle for 300 cycles and retention of 81.7% over 500 cycles at 0.5 C rate can be achieved. This finding and understanding paves an alternative avenue for the future design of sulfur-based cathodes toward the practical application of lithium-sulfur batteries.

Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is inactivated by S-sulfuration in vitro.

PubMed

Jarosz, Artur P; Wei, Wanlei; Gauld, James W; Auld, Janeen; Özcan, Filiz; Aslan, Mutay; Mutus, Bulent

2015-12-01

Hydrogen sulfide (H2S) is produced enzymatically by cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE), as well as other enzymes in mammalian tissues. These discoveries have led to the crowning of H2S as yet another toxic gas that serves as a gasotransmitter like NO and CO. H2S is thought to exert its biological effects through its reaction with cysteine thiols in proteins, yielding sulfurated thiol (-SSH) derivatives. One of the first proteins shown to be modified by H2S was glyceraldehyde 3-phosphate dehydrogenase (GAPDH) [1] where the S-sulfuration of the active site cysteine (Cys 152) resulted in ~7-fold increase in the activity of the enzyme. In the present study we have attempted to reproduce this result with no success. GAPDH in its reduced, or hydrogen peroxide, or glutathione disulfide, or nitrosonium oxidized forms was reacted with sulfide or polysulfides. Sulfide had no effect on reduced GAPDH activity, while polysulfides inhibited GAPDH to ~42% of control. S-sulfuration of GAPDH occurred at Cys 247 after sulfide treatment, Cys 156 and Cys 247 after polysulfide treatment. No evidence of S-sulfuration at active site Cys 152 was discovered. Both sulfide and polysulfide was able to restore the activity of glutathione disulfide oxidized GAPDH, but not to control untreated levels. Treatment of glutathione disulfide oxidized GAPDH with polysulfide also produced S-sulfuration of Cys 156. Treatment of a C156S mutant of GAPDH with sulfide and polysulfide resulted in S-sulfuration of Cys 152, which also caused a decrease and not an increase in enzymatic activity. Computational chemistry shows S-sulfuration of Cys 156 may affect the position of catalytic Cys 152, raising its pKa by 0.5, which may affect the nucleophilicity of Cys 152. The current study raises significant questions about the reported ability of H2S to activate GAPDH by the sulfuration of its active site thiol, and indicates that polysulfide is a stronger protein S-sulfurating agent than sulfide. Copyright © 2015 Elsevier Inc. All rights reserved.

Evaluation of a metering, mixing, and dispensing system for mixing polysulfide adhesive

NASA Technical Reports Server (NTRS)

Evans, Kurt B.

1989-01-01

Tests were performed to evaluate whether a metered mixing system can mix PR-1221 polysulfide adhesive as well as or better than batch-mixed adhesive; also, to evaluate the quality of meter-mixed PR-1860 and PS-875 polysulfide adhesives. These adhesives are candidate replacements for PR-1221 which will not be manufactured in the future. The following material properties were evaluated: peel strength, specific gravity and adhesive components of mixed adhesives, Shore A hardness, tensile adhesion strength, and flow rate. Finally, a visual test called the butterfly test was performed to observe for bubbles and unmixed adhesive. The results of these tests are reported and discussed.

CpsR, a GntR family regulator, transcriptionally regulates capsular polysaccharide biosynthesis and governs bacterial virulence in Streptococcus pneumoniae.

PubMed

Wu, Kaifeng; Xu, Hongmei; Zheng, Yuqiang; Wang, Libin; Zhang, Xuemei; Yin, Yibing

2016-07-08

Transcriptional regulation of capsule expression is critical for pneumococcal transition from carriage to infection, yet the underlying mechanism remains incompletely understood. Here, we describe the regulation of capsular polysaccharide, one of the most important pneumococcal virulence factor by a GntR family regulator, CpsR. Electrophoretic mobility-shift assays have shown the direct interaction between CpsR and the cps promoter (cpsp), and their interaction could be competitively interfered by glucose. DNase I footprinting assays localized the binding site to a region -146 to -114 base pairs relative to the transcriptional start site of the cps locus in S. pneumoniae D39. We found that CpsR negatively controlled the transcription of the cps locus and hence CPS production, which was confirmed by fine-tuning expression of CpsR in a ΔcpsR complemented strain. Increased expression of CpsR in complemented strain led to a decreased resistance to the whole-blood-mediated killing, suggesting a protective role for CpsR-cpsp interaction in the establishment of invasive infection. Finally, animal experiments showed that CpsR-cpsp interaction was necessary for both pneumococcal colonization and invasive infection. Taken together, our results provide a thorough insight into the regulation of capsule production mediated by CpsR and its important roles in pneumococcal pathogenesis.

Synergistically Enhanced Interfacial Interaction to Polysulfide via N,O Dual-Doped Highly Porous Carbon Microrods for Advanced Lithium-Sulfur Batteries.

PubMed

Wang, Nana; Xu, Zhongfei; Xu, Xun; Liao, Ting; Tang, Bin; Bai, Zhongchao; Dou, Shixue

2018-04-25

Lithium-sulfur (Li-S) batteries have received tremendous attention because of their extremely high theoretical capacity (1672 mA h g -1 ) and energy density (2600 W h kg -1 ). Nevertheless, the commercialization of Li-S batteries has been blocked by the shuttle effect of lithium polysulfide intermediates, the insulating nature of sulfur, and the volume expansion during cycling. Here, hierarchical porous N,O dual-doped carbon microrods (NOCMs) were developed as sulfur host materials with a large pore volume (1.5 cm 3 g -1 ) and a high surface area (1147 m 2 g -1 ). The highly porous structure of the NOCMs can act as a physical barrier to lithium polysulfides, while N and O functional groups enhance the interfacial interaction to trap lithium polysulfides, permitting a high loading amount of sulfur (79-90 wt % in the composite). Benefiting from the physical and chemical anchoring effect to prevent shuttling of polysulfides, S@NOCMs composites successfully solve the problems of low sulfur utilization and fast capacity fade and exhibit a stable reversible capacity of 1071 mA h g -1 after 160 cycles with nearly 100% Coulombic efficiency at 0.2 C. The N,O dual doping treatment to porous carbon microrods paves a way toward rational design of high-performance Li-S cathodes with high energy density.

Electrocatalytic activity of lithium polysulfides adsorbed into porous TiO2 coated MWCNTs hybrid structure for lithium-sulfur batteries

PubMed Central

He, Xiulin; Hou, Huijie; Yuan, Xiqing; Huang, Long; Hu, Jingping; Liu, Bingchuan; Xu, Jingyi; Xie, Jia; Yang, Jiakuan; Liang, Sha; Wu, Xu

2017-01-01

Lithium-sulfur batteries have attracted great attention because of their high energy density, environmental friendliness, natural abundance and intrinsically low cost of sulfur. However, their commercial applications are greatly hindered by rapid capacity decay due to poor conductivity of electrode, fast dissolution of the intermediate polysulfides into the electrolyte, and the volume expansion of sulfur. Herein, we report a novel composite MWCNTs@TiO2-S nanostructure by grafting TiO2 onto the surface of MWCNTs, followed by incorporating sulfur into the composite. The inner MWCNTs improved the mechanical strength and conductivity of the electrode and the outer TiO2 provided the adsorption sites to immobilize polysulfides due to bonding interaction between TiO2 and polysulfides. The MWCNTs@TiO2-S composite with a mass ratio of 50% (MWCNTs in MWCNTs@TiO2) exhibited the highest electrochemistry performance among all compositing ratios of MWCNTs/TiO2. The performance improvement might be attributed to the downward shift of the apparent Fermi level to a more positive potential and electron rich space region at the interface of MWCNTs-TiO2 that facilitates the reduction of lithium polysulfide at a higher potential. Such a novel hybrid structure can be applicable for electrode design in other energy storage applications. PMID:28098167

Permselective SPEEK/Nafion Composite-Coated Separator as a Potential Polysulfide Crossover Barrier Layer for Li-S Batteries.

PubMed

Babu, Dasari Bosu; Giribabu, Krishnan; Ramesha, Kannadka

2018-06-13

Minimizing the shuttle effect by constraining polysulfides to the cathode compartment and activating the passive layer between cathode and separator are highly important for improving the Li-S cell performance, Coulombic efficiency, and cycle life. Here, we report a submicron thin coating of permselective sulfonated poly(ether ether ketone) (SPEEK) composite layer on the separator that would reduce polysulfide crossover, imparting a significant improvement in cycle life. It is observed that SPEEK increases the stability, and adding Nafion improves the capacity value. Among different ratios of Nafion and SPEEK (25:75, 50:50, and 75:25), the composite with a SPEEK/Nafion ratio of 50:50 showed a controlled shuttle effect with a stable cell capacity of 600 mA h g -1 up to 300 cycles. This modified separator with permselective coatings not only reduces the polysulfide shuttle but also improves the wettability and interfacial contact, which results in an improvement in average cell potential and lithium diffusivity. It is demonstrated here that the combination of functional (ionomer coating on separator) and nonfunctional (extra cathode layer) physical barriers effectively suppresses the polysulfide crossover and improves the electrochemical performance of Li-S batteries. The cell shows an initial capacity of 1300 mA h g -1 and a capacity retention of 650 mA h g -1 over 500 cycles with a 6 mg/cm 2 sulfur loading.

Shuttle inhibition by chemical adsorption of lithium polysulfides in B and N co-doped graphene for Li-S batteries.

PubMed

Li, Fen; Su, Yan; Zhao, Jijun

2016-09-14

The advance of lithium sulfur batteries is now greatly restricted by the fast capacity fading induced by shuttle effect. Using first-principles calculations, various vacancies, N doping, and B,N co-doping in graphene sheets have been systematically explored for lithium polysufides entrapped in Li-S batteries. The LiS, LiC, LiN and SB bonds and Hirshfeld charges in the Li 2 S 6 adsorbed defective graphene systems have been analyzed to understand the intrinsic mechanism of retaining lithium polysulfides in these systems. Total and local densities of states analyses elucidate the strongest adsorption sites among the N and B-N co-doped graphene systems. The overall electrochemical performance of Li-S batteries varies with the types of defects in graphene. Among the defective graphene systems, only the reconstructed pyrrole-like vacancy is effective for retaining lithium polysulfides. N doping induces a strong LiN interaction in the defective graphene systems, in which the pyrrolic N rather than the pyridinic N plays a dominant role in trapping of lithium polysulfides. The shuttle effect can be further depressed via pyrrolic B,N co-doped defective graphene materials, especially the G-B-N-hex system with extremely strong adsorption of lithium polysulfides (4-5 eV), and simultaneous contribution from the strong LiN and SB interactions.

Elucidating the Solvation Structure and Dynamics of Lithium Polysulfides Resulting from Competitive Salt and Solvent Interactions

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

Rajput, Nav Nidhi; Murugesan, Vijayakumar; Shin, Yongwoo

2017-04-10

Fundamental molecular level understanding of functional properties of liquid solutions provides an important basis for designing optimized electrolytes for numerous applica-tions. In particular, exhaustive knowledge of solvation structure, stability and transport properties is critical for developing stable electrolytes for fast charging and high energy density next-generation energy storage systems. Here we report the correlation between solubility, solvation structure and translational dynamics of a lithium salt (Li-TFSI) and polysulfides species using well-benchmarked classical molecular dynamics simulations combined with nuclear magnetic resonance (NMR). It is observed that the polysulfide chain length has a significant effect on the ion-ion and ion-solvent interaction asmore » well as on the diffusion coefficient of the ionic species in solution. In particular, extensive cluster formation is observed in lower order poly-sulfides (Sx2-; x≤4), whereas the longer polysulfides (Sx2-; x>4) show high solubility and slow dynamics in the solu-tion. It is observed that optimal solvent/salt ratio is essen-tial to control the solubility and conductivity as the addi-tion of Li salt increases the solubility but decreases the mo-bility of the ionic species. This work provides a coupled theoretical and experimental study of bulk solvation struc-ture and transport properties of multi-component electro-lyte systems, yielding design metrics for developing optimal electrolytes with improved stability and solubility.« less

Streptococcus pneumoniae Phosphotyrosine Phosphatase CpsB and Alterations in Capsule Production Resulting from Changes in Oxygen Availability

PubMed Central

Geno, K. Aaron; Hauser, Jocelyn R.; Gupta, Kanupriya

2014-01-01

Streptococcus pneumoniae produces a protective capsular polysaccharide whose production must be modulated for bacterial survival within various host niches. Capsule production is affected in part by a phosphoregulatory system comprised of CpsB, CpsC, and CpsD. Here, we found that growth of serotype 2 strain D39 under conditions of increased oxygen availability resulted in decreased capsule levels concurrent with an ∼5-fold increase in Cps2B-mediated phosphatase activity. The change in Cps2B phosphatase activity did not result from alterations in the levels of either the cps2B transcript or the Cps2B protein. Recombinant Cps2B expressed in Escherichia coli similarly exhibited increased phosphatase activity under conditions of high-oxygen growth. S. pneumoniae D39 derivatives with defined deletion or point mutations in cps2B demonstrated reduced phosphatase activity with corresponding increases in levels of Cps2D tyrosine phosphorylation. There was, however, no correlation between these phenotypes and the level of capsule production. During growth under reduced-oxygen conditions, the Cps2B protein was essential for parental levels of capsule, but phosphatase activity alone could be eliminated without an effect on capsule. Under increased-oxygen conditions, deletion of cps2B did not affect capsule levels. These results indicate that neither Cps2B phosphatase activity nor Cps2D phosphorylation levels per se are determinants of capsule levels, whereas the Cps2B protein is important for capsule production during growth under conditions of reduced but not enhanced oxygen availability. Roles for factors outside the capsule locus, possible interactions between capsule regulatory proteins, and links to other cellular processes are also suggested by the results described in this study. PMID:24659769

In Lactobacillus plantarum, Carbamoyl Phosphate Is Synthesized by Two Carbamoyl-Phosphate Synthetases (CPS): Carbon Dioxide Differentiates the Arginine-Repressed from the Pyrimidine-Regulated CPS

PubMed Central

Nicoloff, Hervé; Hubert, Jean-Claude; Bringel, Françoise

2000-01-01

Carbamoyl phosphate (CP) is an intermediate in pyrimidine and arginine biosynthesis. Carbamoyl-phosphate synthetase (CPS) contains a small amidotransferase subunit (GLN) that hydrolyzes glutamine and transfers ammonia to the large synthetase subunit (SYN), where CP biosynthesis occurs in the presence of ATP and CO2. Lactobacillus plantarum, a lactic acid bacterium, harbors a pyrimidine-inhibited CPS (CPS-P; Elagöz et al., Gene 182:37–43, 1996) and an arginine-repressed CPS (CPS-A). Sequencing has shown that CPS-A is encoded by carA (GLN) and carB (SYN). Transcriptional studies have demonstrated that carB is transcribed both monocistronically and in the carAB arginine-repressed operon. CP biosynthesis in L. plantarum was studied with three mutants (ΔCPS-P, ΔCPS-A, and double deletion). In the absence of both CPSs, auxotrophy for pyrimidines and arginine was observed. CPS-P produced enough CP for both pathways. In CO2-enriched air but not in ordinary air, CPS-A provided CP only for arginine biosynthesis. Therefore, the uracil sensitivity observed in prototrophic wild-type L. plantarum without CO2 enrichment may be due to the low affinity of CPS-A for its substrate CO2 or to regulation of the CP pool by the cellular CO2/bicarbonate level. PMID:10852872

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

Gordon, John Howard; Alvare, Javier

Alkali metals and sulfur may be recovered from alkali monosulfide and polysulfides in an electrolytic process that utilizes an electrolytic cell having an alkali ion conductive membrane. An anolyte solution includes an alkali monosulfide, an alkali polysulfide, or a mixture thereof and a solvent that dissolves elemental sulfur. A catholyte includes molten alkali metal. Applying an electric current oxidizes sulfide and polysulfide in the anolyte compartment, causes alkali metal ions to pass through the alkali ion conductive membrane to the catholyte compartment, and reduces the alkali metal ions in the catholyte compartment. Liquid sulfur separates from the anolyte solution andmore » may be recovered. The electrolytic cell is operated at a temperature where the formed alkali metal and sulfur are molten.« less

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

Azimi, Nasim; Xue, Zheng; Hu, Libo

Lithium difluoro(oxalato) borate (LiDFOB) was investigated as an electrolyte additive for the Li-S battery. This additive was identified to be an efficient electrolyte additive to suppress the polysulfide shuttling effect existing in the conventional Li-S chemistry. To detect the positive impact of the new additive, oligo (ethylene glycol) functionalized silane was employed as the electrolyte solvent due to its high solvation capability with the lithium polysulfides. The electrochemical results and the SEM data of Li-S battery using the new electrolyte confirmed the role of the LiDFOB as a critical component to eliminate the shuttling of the dissolved polysulfides thus enablingmore » a high coulombic efficiency. (C) 2014 Elsevier Ltd. All rights reserved.« less

Graphene oxide as a sulfur immobilizer in high performance lithium/sulfur cells

DOEpatents

Zhang, Yuegang; Cairns, Elton J.; Ji, Liwen; Rao, Mumin

2017-06-06

The loss of sulfur cathode material as a result of polysulfide dissolution causes significant capacity fading in rechargeable lithium/sulfur cells. Embodiments of the invention use a chemical approach to immobilize sulfur and lithium polysulfides via the reactive functional groups on graphene oxide. This approach obtains a uniform and thin (.about.tens of nanometers) sulfur coating on graphene oxide sheets by a chemical reaction-deposition strategy and a subsequent low temperature thermal treatment process. Strong interaction between graphene oxide and sulfur or polysulfides demonstrate lithium/sulfur cells with a high reversible capacity of 950-1400 mAh g.sup.-1, and stable cycling for more than 50 deep cycles at 0.1 C.

Polysulfide and bio-based EP additive performance in vegetable vs. paraffinic base oils

USDA-ARS?s Scientific Manuscript database

Twist compression test (TCT) and 4-ball extreme pressure (EP) methods were used to investigate commercial polysulfide (PS) and bio-based polyester (PE) EP additives in paraffinic (150N) and refined soybean (SOY) base oils of similar viscosity. Binary blends of EP additive and base oil were investiga...

A three-dimensional self-assembled SnS 2 -nano-dots@graphene hybrid aerogel as an efficient polysulfide reservoir for high-performance lithium–sulfur batteries

DOE PAGES

Luo, Liu; Chung, Sheng-Heng; Manthiram, Arumugam

2018-01-01

A free-standing self-assembled graphene aerogel embedded with SnS 2 nano-dots (SnS 2 -ND@G) is established as an efficient substrate for high-loading sulfur cathodes with synergistically physical and chemical polysulfide-trapping capability.

A three-dimensional self-assembled SnS 2 -nano-dots@graphene hybrid aerogel as an efficient polysulfide reservoir for high-performance lithium–sulfur batteries

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

Luo, Liu; Chung, Sheng-Heng; Manthiram, Arumugam

A free-standing self-assembled graphene aerogel embedded with SnS 2 nano-dots (SnS 2 -ND@G) is established as an efficient substrate for high-loading sulfur cathodes with synergistically physical and chemical polysulfide-trapping capability.

Multifunctional Interlayer Based on Molybdenum Diphosphide Catalyst and Carbon Nanotube Film for Lithium-Sulfur Batteries.

PubMed

Luo, Yufeng; Luo, Nannan; Kong, Weibang; Wu, Hengcai; Wang, Ke; Fan, Shoushan; Duan, Wenhui; Wang, Jiaping

2018-02-01

A multifunctional interlayer, composed of molybdenum diphosphide (MoP 2 ) nanoparticles and a carbon nanotube (CNT) film, is introduced into a lithium-sulfur (Li-S) battery system to suppress polysulfide migration. Molybdenum diphosphide acts as the catalyst and can capture polysulfides and improve the polysulfide conversion activity during the discharge/charge processes. The CNT film acts as a conductive skeleton to support the MoP 2 nanoparticles and to ensure their uniform distribution. The CNT film physically hinders polysulfide migration, acts as a current collector, and provides abundant electron pathways. The Li-S battery containing the multifunctional MoP 2 /CNT interlayer exhibits excellent electrochemical performance. It delivers a reversible specific capacity of 905 mA h g -1 over 100 cycles at 0.2 C, with a capacity decay of 0.152% per cycle. These results suggest the introduction of the multifunctional CNT/MoP 2 interlayer as an effective and practical method for producing high-performance Li-S batteries. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Strong lithium polysulfide chemisorption on electroactive sites of nitrogen-doped carbon composites for high-performance lithium-sulfur battery cathodes.

PubMed

Song, Jiangxuan; Gordin, Mikhail L; Xu, Terrence; Chen, Shuru; Yu, Zhaoxin; Sohn, Hiesang; Lu, Jun; Ren, Yang; Duan, Yuhua; Wang, Donghai

2015-03-27

Despite the high theoretical capacity of lithium-sulfur batteries, their practical applications are severely hindered by a fast capacity decay, stemming from the dissolution and diffusion of lithium polysulfides in the electrolyte. A novel functional carbon composite (carbon-nanotube-interpenetrated mesoporous nitrogen-doped carbon spheres, MNCS/CNT), which can strongly adsorb lithium polysulfides, is now reported to act as a sulfur host. The nitrogen functional groups of this composite enable the effective trapping of lithium polysulfides on electroactive sites within the cathode, leading to a much improved electrochemical performance (1200 mAh g(-1) after 200 cycles). The enhancement in adsorption can be attributed to the chemical bonding of lithium ions by nitrogen functional groups in the MNCS/CNT framework. Furthermore, the micrometer-sized spherical structure of the material yields a high areal capacity (ca. 6 mAh cm(-2)) with a high sulfur loading of approximately 5 mg cm(-2), which is ideal for practical applications of the lithium-sulfur batteries. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Stabilized Lithium-Metal Surface in a Polysulfide-Rich Environment of Lithium-Sulfur Batteries.

PubMed

Zu, Chenxi; Manthiram, Arumugam

2014-08-07

Lithium-metal anode degradation is one of the major challenges of lithium-sulfur (Li-S) batteries, hindering their practical utility as next-generation rechargeable battery chemistry. The polysulfide migration and shuttling associated with Li-S batteries can induce heterogeneities of the lithium-metal surface because it causes passivation by bulk insulating Li2S particles/electrolyte decomposition products on a lithium-metal surface. This promotes lithium dendrite formation and leads to poor lithium cycling efficiency with complicated lithium surface chemistry. Here, we show copper acetate as a surface stabilizer for lithium metal in a polysulfide-rich environment of Li-S batteries. The lithium surface is protected from parasitic reactions with the organic electrolyte and the migrating polysulfides by an in situ chemical formation of a passivation film consisting of mainly Li2S/Li2S2/CuS/Cu2S and electrolyte decomposition products. This passivation film also suppresses lithium dendrite formation by controlling the lithium deposition sites, leading to a stabilized lithium surface characterized by a dendrite-free morphology and improved surface chemistry.

Molybdenum polysulfide chalcogels as high-capacity, anion-redox-driven electrode materials for Li-ion batteries

DOE PAGES

Doan-Nguyen, Vicky V. T.; Subrahmanyam, Kota S.; Butala, Megan M.; ...

2016-11-09

Sulfur cathodes in conversion reaction batteries offer high gravimetric capacity but suffer from parasitic polysulfide shuttling. We demonstrate here that transition metal chalcogels of approximate formula MoS 3.4 achieve a high gravimetric capacity close to 600 mAh g –1 (close to 1000 mAh g –1 on a sulfur basis) as electrode materials for lithium-ion batteries. Transition metal chalcogels are amorphous and comprise polysulfide chains connected by inorganic linkers. The linkers appear to act as a “glue” in the electrode to prevent polysulfide shuttling. The Mo chalcogels function as electrodes in carbonate- and ether-based electrolytes, which further provides evidence of polysulfidemore » solubility not being a limiting issue. We employ X-ray spectroscopy and operando pair distribution function techniques to elucidate the structural evolution of the electrode. Raman and X-ray photoelectron spectroscopy track the chemical moieties that arise during the anion-redox-driven processes. As a result, we find the redox state of Mo remains unchanged across the electrochemical cycling and, correspondingly, the redox is anion-driven.« less

Effect of the Hydrofluoroether Cosolvent Structure in Acetonitrile-Based Solvate Electrolytes on the Li+ Solvation Structure and Li-S Battery Performance.

PubMed

Shin, Minjeong; Wu, Heng-Liang; Narayanan, Badri; See, Kimberly A; Assary, Rajeev S; Zhu, Lingyang; Haasch, Richard T; Zhang, Shuo; Zhang, Zhengcheng; Curtiss, Larry A; Gewirth, Andrew A

2017-11-15

We evaluate hydrofluoroether (HFE) cosolvents with varying degrees of fluorination in the acetonitrile-based solvate electrolyte to determine the effect of the HFE structure on the electrochemical performance of the Li-S battery. Solvates or sparingly solvating electrolytes are an interesting electrolyte choice for the Li-S battery due to their low polysulfide solubility. The solvate electrolyte with a stoichiometric ratio of LiTFSI salt in acetonitrile, (MeCN) 2 -LiTFSI, exhibits limited polysulfide solubility due to the high concentration of LiTFSI. We demonstrate that the addition of highly fluorinated HFEs to the solvate yields better capacity retention compared to that of less fluorinated HFE cosolvents. Raman and NMR spectroscopy coupled with ab initio molecular dynamics simulations show that HFEs exhibiting a higher degree of fluorination coordinate to Li + at the expense of MeCN coordination, resulting in higher free MeCN content in solution. However, the polysulfide solubility remains low, and no crossover of polysulfides from the S cathode to the Li anode is observed.

First-Principles Investigation of Lithium Polysulfide Structure and Behavior in Solution

DOE PAGES

Kamphaus, Ethan P.; Balbuena, Perla B.

2017-09-07

We present the Lithium-Sulfur battery is a promising next generation energy storage technology that could meet the demands of modern society with a theoretical specific energy near 2500 W h kg -1. However, this battery chemistry faces unique problems such as the parasitic polysulfide shuttle reaction which hinders battery performance severely. This shuttle phenomenon is caused by solubilities of intermediate reaction products in the electrolyte during the reduction chemistry of the battery. With molecular simulation and computational chemistry tools, we studied the thermodynamics, solvation structure, and dynamics of the long-chain lithium polysulfide species Li 2S 6 and Li 2S 8more » in dimethoxyethane and 1,3-dioxolane to gain a deeper fundamental understanding of this process. We determined the structure of the 1st solvation shell for Li + as well as those of Li 2S 6, Li 2S 8 closed and Li 2S 8 linear in pure solvents and solvents with extra Li + added. Finally, the lithium polysulfide species were found not to favor dissociation and would most likely exist as fully lithiated species in solution.« less

Effect of the Hydrofluoroether Cosolvent Structure in Acetonitrile-Based Solvate Electrolytes on the Li+ Solvation Structure and Li-S Battery Performance.

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

Shin, Minjeong; Wu, Heng-Liang; Narayanan, Badri

We evaluate hydrofluoroether (HFE) cosolvents with varying degrees of fluorination in the acetonitrile-based solvate electrolyte to determine the effect of the HFE structure on the electrochemical performance of the Li-S battery. Solvates or sparingly solvating electrolytes are an interesting electrolyte choice for the Li-S battery due to their low polysulfide solubility. The solvate electrolyte with a stoichiometric ratio of LiTFSI salt in acetonitrile, (MeCN)(2)-LiTFSI, exhibits limited polysulfide solubility due to the high concentration of LiTFSI. We demonstrate that the addition of highly fluorinated HFEs to the solvate yields better capacity retention compared to that of less fluorinated HFE cosolvents. Ramanmore » and NMR spectroscopy coupled with ab initio molecular dynamics simulations show that HFEs exhibiting a higher degree of fluorination coordinate to Li+ at the expense of MeCN coordination, resulting in higher free MeCN content in solution. However, the polysulfide solubility remains low, and no crossover of polysulfides from the S cathode to the Li anode is observed.« less

Reconstruction of multidimensional carbon hosts with combined 0D, 1D and 2D networks for enhanced lithium-sulfur batteries

NASA Astrophysics Data System (ADS)

Li, S. H.; Xia, X. H.; Wang, Y. D.; Wang, X. L.; Tu, J. P.

2017-02-01

It is a core task to find solutions to suppress the "shuttle effect" of polysulfides and improve high rate capability at the sulfur cathode of lithium sulfur batteries. Herein we first time propose a concept of multileveled blocking "dams" to suppress the diffusion of polysulfides. We report a facile and effective strategy to construct multidimensional conductive carbon hosts for accommodation of active sulfur. Multidimensional ternary carbon networks (MTCNs) with 0D nanospheres, 1D nanotubes and 2D nanoflakes are organically combined together to provide multileveled conductive channels to reserve active sulfur and promote stable sustained reactions. In the light of enhanced conductivity and multileveled blocking "dams" for polysulfides, the designed MTCNs/S cathode has been demonstrated with noticeable improvement in discharge capacity (1472 mAh g-1 at 0.l C) and long-term cycling stability (65% retention at 5.0 C after 500 cycles). Our research may provide a new insight in the gradient blocking of polysulfides with the help of multidimensional carbon networks.

Polysulfides as biologically active ingredients of garlic.

PubMed

Münchberg, Ute; Anwar, Awais; Mecklenburg, Susanne; Jacob, Claus

2007-05-21

Garlic has long been considered as a natural remedy against a range of human illnesses, including various bacterial, viral and fungal infections. This kind of antibiotic activity of garlic has mostly been associated with the thiosulfinate allicin. Even so, recent studies have pointed towards a significant biological activity of trisulfides and tetrasulfides found in various Allium species, including a wide range of antibiotic properties and the ability of polysulfides to cause the death of certain cancer cells. The chemistry underlying the biological activity of these polysulfides is currently emerging. It seems to include a combination of several distinct transformations, such as oxidation reactions, superoxide radical and peroxide generation, decomposition with release of highly electrophilic S(x) species, inhibition of metalloenzymes, disturbance of metal homeostasis and membrane integrity and interference with different cellular signalling pathways. Further research in this area is required to provide a better understanding of polysulfide reactions within a biochemical context. This knowledge may ultimately form the basis for the development of 'green' antibiotics, fungicides and possibly anticancer agents with dramatically reduced side effects in humans.

First-Principles Investigation of Lithium Polysulfide Structure and Behavior in Solution

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

Kamphaus, Ethan P.; Balbuena, Perla B.

We present the Lithium-Sulfur battery is a promising next generation energy storage technology that could meet the demands of modern society with a theoretical specific energy near 2500 W h kg -1. However, this battery chemistry faces unique problems such as the parasitic polysulfide shuttle reaction which hinders battery performance severely. This shuttle phenomenon is caused by solubilities of intermediate reaction products in the electrolyte during the reduction chemistry of the battery. With molecular simulation and computational chemistry tools, we studied the thermodynamics, solvation structure, and dynamics of the long-chain lithium polysulfide species Li 2S 6 and Li 2S 8more » in dimethoxyethane and 1,3-dioxolane to gain a deeper fundamental understanding of this process. We determined the structure of the 1st solvation shell for Li + as well as those of Li 2S 6, Li 2S 8 closed and Li 2S 8 linear in pure solvents and solvents with extra Li + added. Finally, the lithium polysulfide species were found not to favor dissociation and would most likely exist as fully lithiated species in solution.« less

Effect of processing conditions on the organosulfides of shallot (Allium cepa L. Aggregatum group).

PubMed

Tocmo, Restituto; Lin, Yi; Huang, Dejian

2014-06-11

There is a growing account of the health benefits of H2S as an endogenous cell-signaling molecule. H2S from organic polysulfides, in particular, is increasingly gaining attention for their beneficial effects to cardiovascular health. Here, we studied shallot as a potential dietary source of organic polysulfides and examined the effects of processing conditions on its polysulfide profiles. Boiling, autoclaving, and freeze-drying were tested on whole and crushed shallot bulbs, analyzing their effect on the yield of organosulfides. Seventeen organosulfides, including disulfides, trisulfides, and cyclic polysulfides, were identified. Significant differences in the quantitative and qualitative profiles of organosulfides in the hydrodistilled and solvent extracted oils were observed. Freeze-drying retained the majority of the organosulfides, but the whole-autoclaved and whole-boiled shallots lost more than 95% of their organic polysulfides. Crushed-boiled and crushed-autoclaved shallot lost 76-80% of their organosulfides, likely due to the thermal sensitivity of these compounds. The organosulfide profiles are sensitive to the pH values of the processing media. In general, disulfides increased at basic pH (pH 9.0) while trisulfides and cyclic organosulfides are much higher at the acidic to neutral pH values (pH 3.0-5.0). Our results provide important information on the effects of processing conditions that are relevant for optimizing extraction of organosulfides from shallot for further studies evaluating their H2S-releasing activity.

Structural Dependence of the Sulfur Reduction Mechanism in Carbon-Based Cathodes for Lithium–Sulfur Batteries

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

Burgos, Juan C.; Balbuena, Perla B.; Montoya, Javier A.

We report lithium-sulfur batteries are promising non-conventional sources of energy due to their high theoretical capacity and energy density. However, the successful implementation of this technology has been hindered due to the low cycling life of the battery, caused by long chain polysulfide shuttling between electrodes during charge/discharge, among other issues. Quantum chemical calculations are used to study the reactivity of sulfur in the porous cathode of lithium-sulfur batteries, and the retention capabilities of porous carbon materials to avoid long chain polysulfide diffusion. Ab initio molecular dynamics (AIMD) simulations are initially employed to evaluate sulfur reduction mechanisms and kinetics, andmore » to identify main reduction products. A porous cathode architecture is modeled through parallel graphene layers with elemental sulfur rings in the interlayer, and filled with 1,3-dioxolane (DOL) organic solvent and lithium ions. AIMD simulations showed fast reduction of elemental sulfur and formation of short chain polysulfide. Furthermore, the effect of dangling carbon bonds of graphene on the reactivity of the cathode was confirmed. Adsorption calculations through density functional theory (DFT) proved the capacity of small pores to retain long polysulfide chains. An analysis of the effect of the specific current on the chemical behavior of sulfur reveals an influence of current on the amount of sulfur utilization and practical specific capacity of the battery. In conclusion, this work illustrates the physical-chemical behavior of the sulfur/polysulfide in the porous cathode system at atomistic level.« less

Structural Dependence of the Sulfur Reduction Mechanism in Carbon-Based Cathodes for Lithium–Sulfur Batteries

DOE PAGES

Burgos, Juan C.; Balbuena, Perla B.; Montoya, Javier A.

2017-08-17

We report lithium-sulfur batteries are promising non-conventional sources of energy due to their high theoretical capacity and energy density. However, the successful implementation of this technology has been hindered due to the low cycling life of the battery, caused by long chain polysulfide shuttling between electrodes during charge/discharge, among other issues. Quantum chemical calculations are used to study the reactivity of sulfur in the porous cathode of lithium-sulfur batteries, and the retention capabilities of porous carbon materials to avoid long chain polysulfide diffusion. Ab initio molecular dynamics (AIMD) simulations are initially employed to evaluate sulfur reduction mechanisms and kinetics, andmore » to identify main reduction products. A porous cathode architecture is modeled through parallel graphene layers with elemental sulfur rings in the interlayer, and filled with 1,3-dioxolane (DOL) organic solvent and lithium ions. AIMD simulations showed fast reduction of elemental sulfur and formation of short chain polysulfide. Furthermore, the effect of dangling carbon bonds of graphene on the reactivity of the cathode was confirmed. Adsorption calculations through density functional theory (DFT) proved the capacity of small pores to retain long polysulfide chains. An analysis of the effect of the specific current on the chemical behavior of sulfur reveals an influence of current on the amount of sulfur utilization and practical specific capacity of the battery. In conclusion, this work illustrates the physical-chemical behavior of the sulfur/polysulfide in the porous cathode system at atomistic level.« less

48 CFR 642.1503-70 - Contractor Performance System (CPS).

Code of Federal Regulations, 2011 CFR

2011-10-01

... Performance System (CPS) maintained by the National Institutes of Health. CPS is an Internet-based tool... with access to the Internet shall use CPS to evaluate contractor's past performance for all contracts... the CPS; or (2) At overseas locations where access to the Internet is not practicable. (d) Heads of...

The genetic organization of the capsular polysaccharide biosynthesis region of Actinobacillus pleuropneumoniae serotype 15

PubMed Central

ITO, Hiroya; SUEYOSHI, Masuo

2014-01-01

Nucleotide sequence determination and analysis of the cps gene involved in the capsular polysaccharide biosynthesis of Actinobacillus pleuropneumoniae serotype 15 revealed the presence of three open reading frames, designated as cps15ABC genes. At the protein level, Cps15A and Cps15B showed considerably high homology to CpsA (67.0 to 68.7%) and CpsB (31.7 to 36.8%), respectively, of A. pleuropneumoniae serotypes 1, 4 and 12, revealing the common genetic organization of the cps among serotypes 1, 4, 12 and 15. However, Cps15C showed no homology to any proteins of A. pleuropneumoniae serotypes, indicating that cps15C may be specific to serotype 15. This study will provide the basic molecular knowledge necessary for the development of diagnostics and a vaccine for A. pleuropneumoniae serotype 15. PMID:25502540

Clues to early diagenetic sulfurization processes from mild chemical cleavage of labile sulfur-rich geomacromolecules

NASA Astrophysics Data System (ADS)

Adam, P.; Schneckenburger, P.; Schaeffer, P.; Albrecht, P.

2000-10-01

Macromolecular fractions, isolated from the solvent extract of sulfur-rich Recent (Siders Pond, USA; Lake Cadagno, Switzerland; Walvis Bay, Namibia) and immature sediments (Gibellina, Messinian of Sicily; Vena del Gesso, Messinian of Italy), were investigated by chemical degradation using sodium ethanethiolate/methyliodide. This mild reagent which cleaves polysulfide bonds to yield methylsulfides has the advantage over other methods of leaving intact other functionalities (like double bonds) and preserving sulfur atoms at their incorporation site. The method is, therefore, well-suited to the molecular level investigation of sulfur-rich macromolecules from Recent sediments containing highly functionalized polysulfide-bound subunits. In Recent anoxic sulfur-rich sediments, the release of various methylthioethers clearly demonstrates that intermolecular sulfurization of organic matter does occur at the earliest stages of diagenesis. Steroids and phytane derivatives are the major sulfurized lipids, a feature also observed in more mature sulfur-rich sediments. Several phytene derivatives, such as cis and trans 1-methylthiophyt-2-enes, as well as methylthiosteroids, including 5α- and 5β-3-(methylthio)-cholest-2-enes, were identified by comparison with synthesized standards. Steroid methylthioenolethers are released from polysulfide-bound steroid enethiols present in the macromolecular fractions. The latter, which correspond to thioketones, can be considered as intermediates in the reductive sulfurization pathway leading from steroid ketones to polysulfide-bound saturated steroid skeletons and are characterized for the first time in the present study. Thus, it could be shown that the major part of the polysulfide-bound lipids occurring in Recent sediments is apparently the result of sulfurization processes affecting carbonyls (aldehydes and ketones). The unsaturated methylthioethers obtained from Recent sediments were not present in more mature evaporitic samples, which suggests that polysulfide-bound unsaturated thiols are intermediates formed during the first sulfurization steps occurring soon after deposition and that they are rapidly transformed by various processes taking place during early diagenesis, notably to yield their saturated counterparts.

Isolation and identification of citrus psorosis virus Egyptian isolate (CPsV-EG).

PubMed

Ghazal, S A; El-Dougdoug, Kh A; Mousa, A A; Fahmy, H; Sofy, A R

2008-01-01

Citrus psorosis ophiovirus (CPsV), is considered to be of the most serious and deter mental virus pathogen's citrus species trees in Egypt. CPsV-EG was isolated from infected citrus grapefruit (C. paradisi Macf.) at Agric. Res. Centre (ARC). The grapefruit which used for CPsV-EG isolate was found to be free from CTV, CEVd and Spiroplasma citri where as gave -ve results with DTBIA, tissue print hybridization and Diene's stain respectively. CPsV-EG was detected on the basis of biological indexing by graft inoculation which gave oak leaf pattern (OLP) on Dweet tangor and serological assay by DAS-ELISA using Mab specific CPsV. CPsV-EG was reacted with variable responses on 16 host plants belonging to 6 families. Only 8 host plants are susceptible and showed visible external symptoms which appeared as local, systemic and local followed by systemic infections. CPsV-EG isolate was transmitted from infected citrus to citrus by syringe and grafting and herbaceous plants by forefinger inoculation and syringe. The woody indicators and rootstocks were differed in response to CPsV-EG isolate which appeared as no-response, response, sensitivity and hypersensitivity. The serological characters represented as the antigenic determinants of CPsV-EG isolate related to monoclonal antibodies specific CPsV strain where as appeared precipitation reaction by DAS-ELISA and DTBIA. The partial fragment of RNA3 (coat protein gene) of CPsV-EG (-1140bp and -571bp) was amplified by reverse transcription-polymerase chain reaction (RT-PCR) from grapefruit tissues using two sets primers specific CPsV (CPV3 and CPV4) and (PS66 and PS65) respectively. The virus under study was identified as CPsV-EG isolate according to biological, serological and molecular characters.

Effect of Different Administration Paradigms on Cholinesterase Inhibition following Repeated Chlorpyrifos Exposure in Late Preweanling Rats

PubMed Central

Carr, Russell L.; Nail, Carole A.

2008-01-01

Chlorpyrifos (CPS) is widely used in agricultural settings and residue analysis has suggested that children in agricultural communities are at risk of exposure. This has resulted in a large amount of literature investigating the potential for CPS-induced developmental neurotoxic effects. Two developmental routes of administration of CPS are orally in corn oil at a rate of 0.5 ml/kg and subcutaneously in dimethyl sulfoxide (DMSO) at a rate of 1.0 ml/kg. For comparison between these methods, rat pups were exposed daily from days 10 to 16 to CPS (5 mg/kg) either orally dissolved in corn oil or subcutaneously dissolved in DMSO, both at rates of either 0.5 or 1.0 ml/kg. A representative vehicle/route group was present for each treatment. Both the low and high volume CPS in DMSO subcutaneous groups were lower than that of the low and high volume CPS in oil oral groups. At 4 h following the final administration, serum carboxylesterase was inhibited > 90% with all treatments. For cholinesterase activity in the cerebellum, medulla-pons, forebrain, and hindbrain, and serum, inhibition in the CPS-oil groups was similar and inhibition in the CPS-DMSO groups was similar. However, significantly greater inhibition was present in the high volume CPS-DMSO group as compared to the CPS-oil groups. Inhibition in the low volume CPS-DMSO group was generally between that in the CPS-oil groups and the high volume CPS-DMSO group. These data suggest that using DMSO as a vehicle for CPS may alter the level of brain ChE inhibition. PMID:18703558

Comparative study on nutritional and sensory quality of barnyard and foxtail millet food products with traditional rice products.

PubMed

Verma, Suman; Srivastava, Sarita; Tiwari, Neha

2015-08-01

Millets have the potential to contribute to food security and nutrition, but still these are underutilized crops. The present study was undertaken with a view to analyse the physico-chemical, functional and nutritional composition of foxtail millet, barnyard millet and rice and to compare the sensory quality and nutritive value of food products from foxtail and barnyard millet with rice. Analysis of physico- chemical and functional characteristics revealed that the thousand kernel weight of foxtail millet, barnyard millet and rice was 2.5, 3.0 and 18.3 g, respectively and thousand kernel volume was 1.6, 13 2.0 and 7.1 ml, respectively. The water absorption capacity of foxtail millet, barnyard millet and rice was 1.90, 1.96 and 1.98 ml/g, respectively and water solubility index was 2.8, 1.2 and 1.0 %, respectively. Viscosity was measured for foxtail millet (1650.6 cps), barnyard millet (1581 cps) and rice (1668.3 cps). Analysis of nutritional composition showed that the moisture content of foxtail millet, barnyard millet and rice was 9.35, 11.93 and 11.91 %, respectively. The total ash, crude protein, crude fat, crude fibre and carbohydrate of foxtail millet were 3.10, 10.29, 3.06, 4.25 and 69.95 %, respectively, for barnyard millet were 4.27, 6.93, 2.02, 2.98 and 71.87 %, respectively and the corresponding values for rice were 0.59, 6.19, 0.53, 0.21 and 80.58 %, respectively. The energy value for foxtail millet, barnyard millet and rice was 349, 407 and 352 Kcal, respectively. The foxtail millet contained 30.10 mg/100 g calcium and 3.73 mg/100 g iron whereas barnyard millet contained 23.16 mg/100 g calcium and 6.91 mg/100 g iron. Values of 10 mg/100 g calcium and 0.10 mg/100 g iron were observed for rice. The formulated products viz. laddu, halwa and biryani from foxtail millet, barnyard millet and rice (control) were analysed for their sensory qualities. Among the products prepared, there was non significant difference with regard to the colour, flavor, texture, appearance and overall acceptability of foxtail and barnyard millet laddu and halwa when compared to control. Foxtail millet biryani was most acceptable compared to barnyard millet and control biryani. Nutritive value of formulated products was calculated and it was compared with the rice. The protein, fat and fibre content of the formulated products from foxtail and barnyard millet were higher than the rice products. Thus from the present study it was concluded that the foxtail millet and barnyard millet are superior in nutritive value to rice and have potential for use in traditional food products.

Sequence Elements Upstream of the Core Promoter Are Necessary for Full Transcription of the Capsule Gene Operon in Streptococcus pneumoniae Strain D39

PubMed Central

Wen, Zhensong; Sertil, Odeniel; Cheng, Yongxin; Zhang, Shanshan; Liu, Xue; Wang, Wen-Ching

2015-01-01

Streptococcus pneumoniae is a major bacterial pathogen in humans. Its polysaccharide capsule is a key virulence factor that promotes bacterial evasion of human phagocytic killing. While S. pneumoniae produces at least 94 antigenically different types of capsule, the genes for biosynthesis of almost all capsular types are arranged in the same locus. The transcription of the capsular polysaccharide (cps) locus is not well understood. This study determined the transcriptional features of the cps locus in the type 2 virulent strain D39. The initial analysis revealed that the cps genes are cotranscribed from a major transcription start site at the −25 nucleotide (G) upstream of cps2A, the first gene in the locus. Using unmarked chromosomal truncations and a luciferase-based transcriptional reporter, we showed that the full transcription of the cps genes not only depends on the core promoter immediately upstream of cps2A, but also requires additional elements upstream of the core promoter, particularly a 59-bp sequence immediately upstream of the core promoter. Unmarked deletions of these promoter elements in the D39 genome also led to significant reduction in CPS production and virulence in mice. Lastly, common cps gene (cps2ABCD) mutants did not show significant abnormality in cps transcription, although they produced significantly less CPS, indicating that the CpsABCD proteins are involved in the encapsulation of S. pneumoniae in a posttranscriptional manner. This study has yielded important information on the transcriptional characteristics of the cps locus in S. pneumoniae. PMID:25733517

Doped carbon-sulfur species nanocomposite cathode for Li--S batteries

DOEpatents

Wang, Donghai; Xu, Tianren; Song, Jiangxuan

2015-12-29

We report a heteroatom-doped carbon framework that acts both as conductive network and polysulfide immobilizer for lithium-sulfur cathodes. The doped carbon forms chemical bonding with elemental sulfur and/or sulfur compound. This can significantly inhibit the diffusion of lithium polysulfides in the electrolyte, leading to high capacity retention and high coulombic efficiency.

Lithium-Polysulfide Flow Battery Demonstration

ScienceCinema

Zheng, Wesley

2018-01-16

In this video, Stanford graduate student Wesley Zheng demonstrates the new low-cost, long-lived flow battery he helped create. The researchers created this miniature system using simple glassware. Adding a lithium polysulfide solution to the flask immediately produces electricity that lights an LED. A utility version of the new battery would be scaled up to store many megawatt-hours of energy.

Graphene oxide as a sulfur immobilizer in high performance lithium/sulfur cells

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

Zhang, Yuegang; Cairns, Elton J.; Ji, Liwen

The loss of sulfur cathode material as a result of polysulfide dissolution causes significant capacity fading in rechargeable lithium/sulfur cells. Embodiments of the invention use a chemical approach to immobilize sulfur and lithium polysulfides via the reactive functional groups on graphene oxide. This approach obtains a uniform and thin (.about.tens of nanometers) sulfur coating on graphene oxide sheets by a chemical reaction-deposition strategy and a subsequent low temperature thermal treatment process. Strong interaction between graphene oxide and sulfur or polysulfides demonstrate lithium/sulfur cells with a high reversible capacity of 950-1400 mAh g.sup.-1, and stable cycling for more than 50 deepmore » cycles at 0.1 C.« less

Organization of the capsule biosynthesis gene locus of the oral streptococcus Streptococcus anginosus.

PubMed

Tsunashima, Hiroyuki; Miyake, Katsuhide; Motono, Makoto; Iijima, Shinji

2012-03-01

The capsular polysaccharide (CPS) of the important oral streptococcus Streptococcus anginosus, which causes endocarditis, and the genes for its synthesis have not been clarified. In this study, we investigated the gene locus required for CPS synthesis in S. anginosus. Southern hybridization using the cpsE gene of the well-characterized bacterium S. agalactiae revealed that there is a similar gene in the genome of S. anginosus. By using the colony hybridization technique and inverse PCR, we isolated the CPS synthesis (cps) genes of S. anginosus. This gene cluster consisted of genes containing typical regulatory genes, cpsA-D, and glycosyltransferase genes coding for glucose, rhamnose, N-acetylgalactosamine, and galactofuranose transferases. Furthermore, we confirmed that the cps locus is required for CPS synthesis using a mutant strain with a defective cpsE gene. The cps cluster was found to be located downstream the nrdG gene, which encodes ribonucleoside triphosphate reductase activator, as is the case in other oral streptococci such as S. gordonii and S. sanguinis. However, the location of the gene cluster was different from those of S. pneumonia and S. agalactiae. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Recurrence of carbamoyl phosphate synthetase 1 (CPS1) deficiency in Turkish patients: characterization of a founder mutation by use of recombinant CPS1 from insect cells expression.

PubMed

Hu, Liyan; Diez-Fernandez, Carmen; Rüfenacht, Véronique; Hismi, Burcu Öztürk; Ünal, Özlem; Soyucen, Erdogan; Çoker, Mahmut; Bayraktar, Bilge Tanyeri; Gunduz, Mehmet; Kiykim, Ertugrul; Olgac, Asburce; Pérez-Tur, Jordi; Rubio, Vicente; Häberle, Johannes

2014-12-01

Carbamoyl phosphate synthetase 1 (CPS1) deficiency due to CPS1 mutations is a rare autosomal-recessive urea cycle disorder causing hyperammonemia that can lead to death or severe neurological impairment. CPS1 catalyzes carbamoyl phosphate formation from ammonia, bicarbonate and two molecules of ATP, and requires the allosteric activator N-acetyl-L-glutamate. Clinical mutations occur in the entire CPS1 coding region, but mainly in single families, with little recurrence. We characterized here the only currently known recurrent CPS1 mutation, p.Val1013del, found in eleven unrelated patients of Turkish descent using recombinant His-tagged wild type or mutant CPS1 expressed in baculovirus/insect cell system. The global CPS1 reaction and the ATPase and ATP synthesis partial reactions that reflect, respectively, the bicarbonate and the carbamate phosphorylation steps, were assayed. We found that CPS1 wild type and V1013del mutant showed comparable expression levels and purity but the mutant CPS1 exhibited no significant residual activities. In the CPS1 structural model, V1013 belongs to a highly hydrophobic β-strand at the middle of the central β-sheet of the A subdomain of the carbamate phosphorylation domain and is close to the predicted carbamate tunnel that links both phosphorylation sites. Haplotype studies suggested that p.Val1013del is a founder mutation. In conclusion, the mutation p.V1013del inactivates CPS1 but does not render the enzyme grossly unstable or insoluble. Recurrence of this particular mutation in Turkish patients is likely due to a founder effect, which is consistent with the frequent consanguinity observed in the affected population. Copyright © 2014 Elsevier Inc. All rights reserved.

Durability of the Li 1+xTi 2–xAl x(PO 4) 3 Solid Electrolyte in Lithium–Sulfur Batteries

DOE PAGES

Wang, Shaofei; Ding, Yu; Zhou, Guangmin; ...

2016-10-31

Adoption of cells with a solid-state electrolyte is a promising solution for eliminating the polysulfide shuttle problem in Li-S batteries. Among the various known lithium-ion conducting solid electrolytes, the sodium superionic conductor (NASICON)-type Li 1+xTi 2-xAl x(PO 4) 3 offers the advantage of good stability under ambient conditions and in contact with air. Accordingly, we present here a comprehensive assessment of the durability of Li 1+xTi 2-xAl x(PO 4) 3 in contact with polysulfide solution and in Li-S cells. Because of its high reduction potential (2.5 V vs Li/Li +), Li 1+xTi 2-xAl x(PO 4) 3 gets lithiated in contactmore » with lithium polysulfide solution and Li 2CO 3 is formed on the particle surface, blocking the interfacial lithium-ion transport between the liquid and solid-state electrolytes. After the lithium insertion into the NASICON framework, the crystal expands in an anisotropic way, weakening the crystal bonds, causing fissures and resultant cracks in the ceramic, corroding the grain boundaries by polysulfide solution, and leaving unfavorable pores. The assembly of pores creates a gateway for polysulfide diffusion from the cathode side to the anode side, causing an abrupt decline in cell performance. Therefore, the solid-state electrolytes need to have good chemical compatibility with both the electrode and electrolyte, long-term stability under harsh chemical environment, and highly stable grain boundaries.« less

A nickel-foam@carbon-shell with a pie-like architecture as an efficient polysulfide trap for high-energy Li–S batteries

DOE PAGES

Luo, Liu; Chung, Sheng-Heng; Chang, Chi-Hao; ...

2017-07-06

A high-loading sulfur cathode is critical for establishing rechargeable lithium–sulfur (Li–S) batteries with the anticipated high energy density. However, its fabrication as well as realizing high electrochemical utilization and stability with high-loading sulfur cathodes is a daunting challenge. Here, we present a new pie-like electrode that consists of an electrocatalytic nickel-foam as a “filling” to adsorb and store polysulfide catholytes and an outer carbon shell as a “crust” for facilitating high-loading sulfur cathodes with superior electrochemical and structural stabilities. The inner electrocatalytic nickel-foam is configured to adsorb polysulfides and facilitate their redox reactions. The intertwined carbon shell assists to shieldmore » the polysulfides within the cathode region of the cell. Both the nickel-foam and the carbon shell have high conductivity and porous space, which serve simultaneously as interconnected current collectors to enhance the redox kinetics and as polysulfide reservoirs to confine the active material. The effectiveness of such a pie-like structure in improving the electrochemical efficiency enables the cathode to host an ultrahigh sulfur loading of 40 mg cm -2 and attain a high areal capacity of over 40 mA h cm -2 at a low electrolyte/sulfur (E/S) ratio of 7. The enhanced cyclability is reflected in a high reversible areal capacity approaching 30 mA h cm -2 at C/5 rate after 100 cycles and excellent rate capability up to 2C rate.« less

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

Chung, Sheng-Heng; Chang, Chi-Hao; Manthiram, Arumugam

Sulfur is an appealing cathode material for establishing advanced lithium batteries as it offers a high theoretical capacity of 1675 mA h g -1 at low material and operating costs. However, the lithium–sulfur (Li–S) electrochemical cells face several formidable challenges arising from both the materials chemistry (e.g., low electrochemical utilization of sulfur and severe polysulfide diffusion) and battery chemistry (e.g., dynamic and static instability and low sulfur loadings). Here in this study, we present the design of a core–shell cathode with a pure sulfur core shielded within a conductive shell-shaped electrode. The new electrode configuration allows Li–S cells to loadmore » with a high amount of sulfur (sulfur loadings of up to 30 mg cm -2 and sulfur content approaching 70 wt%). The core–shell cathodes demonstrate a superior dynamic and static electrochemical stability in Li–S cells. The high-loading cathodes exhibit (i) a high sulfur utilization of up to 97% at C/20–C/2 rates and (ii) a low self-discharge during long-term cell storage for a three-month rest period and at different cell-storage conditions. Finally, a polysulfide-trap cell configuration is designed to evidence the eliminations of polysulfide diffusion and to investigate the relationship between the electrode configuration and electrochemical characteristics. Finally, the comprehensive analytical results based on the high-loading cathodes suggest that (i) the core–shell cathode is a promising solution for designing highly reversible Li–S cells and (ii) the polysulfide-trap cell configuration is a viable approach to qualitatively evaluating the presence or absence of polysulfide diffusion.« less

A nickel-foam@carbon-shell with a pie-like architecture as an efficient polysulfide trap for high-energy Li–S batteries

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

Luo, Liu; Chung, Sheng-Heng; Chang, Chi-Hao

A high-loading sulfur cathode is critical for establishing rechargeable lithium–sulfur (Li–S) batteries with the anticipated high energy density. However, its fabrication as well as realizing high electrochemical utilization and stability with high-loading sulfur cathodes is a daunting challenge. Here, we present a new pie-like electrode that consists of an electrocatalytic nickel-foam as a “filling” to adsorb and store polysulfide catholytes and an outer carbon shell as a “crust” for facilitating high-loading sulfur cathodes with superior electrochemical and structural stabilities. The inner electrocatalytic nickel-foam is configured to adsorb polysulfides and facilitate their redox reactions. The intertwined carbon shell assists to shieldmore » the polysulfides within the cathode region of the cell. Both the nickel-foam and the carbon shell have high conductivity and porous space, which serve simultaneously as interconnected current collectors to enhance the redox kinetics and as polysulfide reservoirs to confine the active material. The effectiveness of such a pie-like structure in improving the electrochemical efficiency enables the cathode to host an ultrahigh sulfur loading of 40 mg cm -2 and attain a high areal capacity of over 40 mA h cm -2 at a low electrolyte/sulfur (E/S) ratio of 7. The enhanced cyclability is reflected in a high reversible areal capacity approaching 30 mA h cm -2 at C/5 rate after 100 cycles and excellent rate capability up to 2C rate.« less

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

Vitvitsky, Victor; Yadav, Pramod K.; An, Sojin

Hydrogen sulfide is a cardioprotective signaling molecule but is toxic at elevated concentrations. Red blood cells can synthesize H2S but, lacking organelles, cannot dispose of H2S via the mitochondrial sulfide oxidation pathway. We have recently shown that at high sulfide concentrations, ferric hemoglobin oxidizes H2S to a mixture of thiosulfate and iron-bound polysulfides in which the latter species predominates. Here, we report the crystal structure of human hemoglobin containing low spin ferric sulfide, the first intermediate in heme-catalyzed sulfide oxidation. The structure provides molecular insights into why sulfide is susceptible to oxidation in human hemoglobin but is stabilized against itmore » in HbI, a specialized sulfide-carrying hemoglobin from a mollusk adapted to life in a sulfide-rich environment. We have also captured a second sulfide bound at a postulated ligand entry/exit site in the α-subunit of hemoglobin, which, to the best of our knowledge, represents the first direct evidence for this site being used to access the heme iron. Hydrodisulfide, a postulated intermediate at the junction between thiosulfate and polysulfide formation, coordinates ferric hemoglobin and, in the presence of air, generated thiosulfate. At low sulfide/heme iron ratios, the product distribution between thiosulfate and iron-bound polysulfides was approximately equal. The iron-bound polysulfides were unstable at physiological glutathione concentrations and were reduced with concomitant formation of glutathione persulfide, glutathione disulfide, and H2S. Hence, although polysulfides are unlikely to be stable in the reducing intracellular milieu, glutathione persulfide could serve as a persulfide donor for protein persulfidation, a posttranslational modification by which H2S is postulated to signal.« less

Polysaccharides obtained from bamboo shoots (Chimonobambusa quadrangularis) processing by-products: New insight into ethanol precipitation and characterization.

PubMed

Zhang, Fusheng; Ran, ChunXia; Zheng, Jiong; Ding, Yongbo; Chen, Guangjing

2018-06-01

Chimonobambusa quadrangularis polysaccharides (CPS) were extracted by ultrasonic-assisted extraction from bamboo shoots (C. quadrangularis) processing by-products. Three polysaccharide fractions, CPS70, CPS75 and CPS80, were obtained by precipitation at final ethanol concentrations of 70%, 75% and 80%, respectively. The physicochemical characterization and chemical antioxidant activities of the three polysaccharide fractions were compared on the basis of HPLC, FT-IR, XRD, TGA, and antioxidant measurements in vitro. The results suggested that ethanol concentrations used for precipitation of CPS can affect its physicochemical and associated functional properties, and antioxidant activities. Compared with CPS70 and CPS80, CPS75 had lower glucose content, higher total sugar content, and higher protein and uronic acid contents. The CPS70 and CPS80 were composed of Man, Rha, GlcA, Glc, Gal, Xyl and Ara, but none of them were found to contain GalA. In contrast, CPS75 consisted of Man, Rha, GlcA, GalA, Glc, Gal, Xyl and Ara. CPS75 had the lowest medium-high-molecular-weight value (116.53-118.18kDa) and the highest medium-low-molecular-weight value (21.30-22.68kDa). Meanwhile, CPS75 exhibited better functional properties including the repose angle, swelling capacity (SC), water retention capacity (WRC), and oil retention capacity (ORC). Moreover, CPS75 possessed higher scavenging capacities on DPPH, hydroxyl and ABTS radicals, higher oxygen radical absorbance capacity (OARC), higher metal chelating activity, and more significant reducing power. According to the results above, a final ethanol concentration of 75% could be chose to precipitate polysaccharides from bamboo shoots (C. quadrangularis) processing by-products. In summary, it is strongly recommended that the ethanol concentration employed in precipitation of natural polysaccharides could be optimized in advance. Copyright © 2018 Elsevier B.V. All rights reserved.

Neurophysiological Correlates of Musical and Prosodic Phrasing: Shared Processing Mechanisms and Effects of Musical Expertise.

PubMed

Glushko, Anastasia; Steinhauer, Karsten; DePriest, John; Koelsch, Stefan

2016-01-01

The processing of prosodic phrase boundaries in language is immediately reflected by a specific event-related potential component called the Closure Positive Shift (CPS). A component somewhat reminiscent of the CPS in language has also been reported for musical phrases (i.e., the so-called 'music CPS'). However, in previous studies the quantification of the music-CPS as well as its morphology and timing differed substantially from the characteristics of the language-CPS. Therefore, the degree of correspondence between cognitive mechanisms of phrasing in music and in language has remained questionable. Here, we probed the shared nature of mechanisms underlying musical and prosodic phrasing by (1) investigating whether the music-CPS is present at phrase boundary positions where the language-CPS has been originally reported (i.e., at the onset of the pause between phrases), and (2) comparing the CPS in music and in language in non-musicians and professional musicians. For the first time, we report a positive shift at the onset of musical phrase boundaries that strongly resembles the language-CPS and argue that the post-boundary 'music-CPS' of previous studies may be an entirely distinct ERP component. Moreover, the language-CPS in musicians was found to be less prominent than in non-musicians, suggesting more efficient processing of prosodic phrases in language as a result of higher musical expertise.

Bacterial degradation of chlorophenols and their derivatives

PubMed Central

2014-01-01

Chlorophenols (CPs) and their derivatives are persistent environmental pollutants which are used in the manufacture of dyes, drugs, pesticides and other industrial products. CPs, which include monochlorophenols, polychlorophenols, chloronitrophenols, chloroaminophenols and chloromethylphenols, are highly toxic to living beings due to their carcinogenic, mutagenic and cytotoxic properties. Several physico-chemical and biological methods have been used for removal of CPs from the environment. Bacterial degradation has been considered a cost-effective and eco-friendly method of removing CPs from the environment. Several bacteria that use CPs as their sole carbon and energy sources have been isolated and characterized. Additionally, the metabolic pathways for degradation of CPs have been studied in bacteria and the genes and enzymes involved in the degradation of various CPs have been identified and characterized. This review describes the biochemical and genetic basis of the degradation of CPs and their derivatives. PMID:24589366

Is overprotection of the sulfur cathode good for Li-S batteries?

PubMed

Gao, Tian; Shao, Jie; Li, Xingxing; Zhu, Guobin; Lu, Qiujian; Han, Yuyao; Qu, Qunting; Zheng, Honghe

2015-08-11

How to restrain the dissolution of polysulfides from the sulfur cathode is the current research focus of Li-S batteries. Here, we find that moderate dissolution of polysulfides is of great importance for high-efficiency and stable discharge/charge cycling. Both overprotection and inadequate protection of the sulfur cathode are unfavorable for the cycling of Li-S batteries.

A novel quasi-solid state electrolyte with highly effective polysulfide diffusion inhibition for lithium-sulfur batteries

PubMed Central

Zhong, Hai; Wang, Chunhua; Xu, Zhibin; Ding, Fei; Liu, Xinjiang

2016-01-01

Polymer solid state electrolytes are actively sought for their potential application in energy storage devices, particularly lithium metal rechargeable batteries. Herein, we report a polymer with high concentration salts as a quasi-solid state electrolyte used for lithium-sulfur cells, which shows an ionic conductivity of 1.6 mS cm−1 at room temperature. The cycling performance of Li-S battery with this electrolyte shows a long cycle life (300 cycles) and high coulombic efficiency (>98%), without any consuming additives in the electrolyte. Moreover, it also shows a remarkably decreased self-discharge (only 0.2%) after storage for two weeks at room temperature. The reason can be attributed to that the electrolyte can suppress polysulfide anions diffusion, due to the high ratio oxygen atoms with negative charges which induce an electrical repulsion to the polysulfide anions, and their relatively long chains which can provide additional steric hindrance. Thus, the polysulfide anions can be located around carbon particles, which result in remarkably improved overall electrochemical performance, and also the electrolyte have a function of suppress the formation of lithium dendrites on the lithium anode surface. PMID:27146645

Ab initio crystal structure prediction of magnesium (poly)sulfides and calculation of their NMR parameters.

PubMed

Mali, Gregor

2017-03-01

Ab initio prediction of sensible crystal structures can be regarded as a crucial task in the quickly-developing methodology of NMR crystallography. In this contribution, an evolutionary algorithm was used for the prediction of magnesium (poly)sulfide crystal structures with various compositions. The employed approach successfully identified all three experimentally detected forms of MgS, i.e. the stable rocksalt form and the metastable wurtzite and zincblende forms. Among magnesium polysulfides with a higher content of sulfur, the most probable structure with the lowest formation energy was found to be MgS 2 , exhibiting a modified rocksalt structure, in which S 2- anions were replaced by S 2 2- dianions. Magnesium polysulfides with even larger fractions of sulfur were not predicted to be stable. For the lowest-energy structures, 25 Mg quadrupolar coupling constants and chemical shift parameters were calculated using the density functional theory approach. The calculated NMR parameters could be well rationalized by the symmetries of the local magnesium environments, by the coordination of magnesium cations and by the nature of the surrounding anions. In the future, these parameters could serve as a reference for the experimentally determined 25 Mg NMR parameters of magnesium sulfide species.

Development of cost-effective noncarbon sorbents for Hg(0) removal from coal-fired power plants.

PubMed

Lee, Joo-Youp; Ju, Yuhong; Keener, Tim C; Varma, Rajender S

2006-04-15

Noncarbonaceous materials or mineral oxides (silica gel, alumina, molecular sieves, zeolites, and montmorillonite) were modified with various functional groups such as amine, amide, thiol, urea, and active additives such as elemental sulfur, sodium sulfide, and sodium polysulfide to examine their potential as sorbents for the removal of elemental mercury (Hg(0)) vapor at coal-fired utility power plants. A number of sorbent candidates such as amine- silica gel, urea- silica gel, thiol- silica gel, amide-silica gel, sulfur-alumina, sulfur-molecular sieve, sulfur-montmorillonite, sodium sulfide-montmorillonite, and sodium polysulfide-montmorillonite, were synthesized and tested in a lab-scale fixed-bed system under an argon flow for screening purposes at 70 degrees C and/or 140 degrees C. Several functionalized silica materials reported in previous studies to effectively control heavy metals in the aqueous phase showed insignificant adsorption capacities for Hg(0) control in the gas phase, suggesting that mercury removal mechanisms in both phases are different. Among elemental sulfur-, sodium sulfide-, and sodium polysulfide-impregnated inorganic samples, sodium polysulfide-impregnated montmorillonite K 10 showed a moderate adsorption capacity at 70 degrees C, which can be used for sorbent injection prior to the wet FGD system.

Improving the capacity of lithium-sulfur batteries by tailoring the polysulfide adsorption efficiency of hierarchical oxygen/nitrogen-functionalized carbon host materials.

PubMed

Schneider, Artur; Janek, Jürgen; Brezesinski, Torsten

2017-03-22

The use of monolithic carbons with structural hierarchy and varying amounts of nitrogen and oxygen functionalities as sulfur host materials in high-loading lithium-sulfur cells is reported. The primary focus is on the strength of the polysulfide/carbon interaction with the goal of assessing the effect of (surface) dopant concentration on cathode performance. The adsorption capacity - which is a measure of the interaction strength between the intermediate lithium polysulfide species and the carbon - was found to scale almost linearly with the nitrogen level. Likewise, the discharge capacity of lithium-sulfur cells increased linearly. This positive correlation can be explained by the favorable effect of nitrogen on both the chemical and electronic properties of the carbon host. The incorporation of additional oxygen-containing surface groups into highly nitrogen-functionalized carbon helped to further enhance the polysulfide adsorption efficiency, and therefore the reversible cell capacity. Overall, the areal capacity could be increased by almost 70% to around 3 mA h cm -2 . We believe that the design parameters described here provide a blueprint for future carbon-based nanocomposites for high-performance lithium-sulfur cells.

Inhibiting polysulfides diffusion of lithium-sulfur batteries using an acetylene black-CoS2 modified separator: Mechanism research and performance improvement

NASA Astrophysics Data System (ADS)

Zeng, Pan; Huang, Liwu; Zhang, Xinling; Han, Yamiao; Chen, Yungui

2018-01-01

Lithium-sulfur (Li-S) batteries are considered as one of the most promising chemistries in secondary energy storage field owing to their high energy density. However, the poor electrochemical performance mainly associated with the polysulfides shuttle has greatly hampered their practical application. Herein, a simple acetylene black (AB)-CoS2 coated separator is first designed to suppress the migration of polysulfides. The AB-CoS2 modified separator can not only efficiently capture the polysulfides by forming strong chemical bonding but also guarantee the rapid lithium ions diffusion. Moreover, the AB-CoS2 coating could serve as an upper current collector to accelerate electron transport for reinforcing the utilization of sulfur and ensuring the reactivation of the trapped active material. Consequently, the Li-S cell using AB-CoS2 modified separator shows a long-term cycling stability with an extremely low decay rate (0.09% per cycle) up to 450 cycles at a high rate of 2 C (3350 mA g-1). It also exhibits excellent rate capabilities, which maintains a capacity of 475 mAh g-1 even at 4.0 C rate.

Restricting the Solubility of Polysulfides in Li-S Batteries Via Electrolyte Salt Selection

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

Chen, Junzheng; Han, Kee Sung; Henderson, Wesley A.

2016-03-29

Polysulfide solubility in the electrolyte has a critical role to the Li-S battery but the mechanism study on the solubility needs to be carefully carried out. In this paper we found that lithium 2-trifluoromethyl-4,5-dicyanoimidazole (LiTDI) reveals a suppression of the polysulfide solubility in electrolytes (relative to the most widely used electrolyte formulation) and the Li-S cells achieved homogeneous stable capacity retention upon extensive cycling and Li metal deposition on the anode. Combined experimental, simulation and calculation methods suggest the dominate disproportionation product of Li2S8 is Li2S4 in the LiTDI electrolyte due to a different interaction between lithium ion and TDImore » anion. The Li2S4 would continuesly form a Li4S8 dimer and be fully locallized to precipitate out. The use of the electrolyte with the LiTDI salt (with polysulfide and LiNO3 additives) enabled a cell with a high sulfur (3 mg-S cm-2) loading to deliver a 1.67 mAh cm-2 areal capacity after 300 stable cycles at a high current (2.4 mA cm-2) density.« less

Redox Signaling Regulated by Cysteine Persulfide and Protein Polysulfidation.

PubMed

Kasamatsu, Shingo; Nishimura, Akira; Morita, Masanobu; Matsunaga, Tetsuro; Abdul Hamid, Hisyam; Akaike, Takaaki

2016-12-15

For decades, reactive persulfide species including cysteine persulfide (CysSSH) have been known to exist endogenously in organisms. However, the physiological significance of endogenous persulfides remains poorly understood. That cystathionine β-synthase and cystathionine γ-lyase produced CysSSH from cystine was recently demonstrated. An endogenous sulfur transfer system involving CysSSH evidently generates glutathione persulfide (GSSH) that exists at concentrations greater than 100 μM in vivo. Because reactive persulfide species such as CysSSH and GSSH have higher nucleophilicity than parental cysteine (Cys) and glutathione do, these reactive species exhibit strong scavenging activities against oxidants, e.g., hydrogen peroxide, and electrophiles, which contributes to redox signaling regulation. Also, several papers indicated that various proteins and enzymes have Cys polysulfides including CysSSH at their specific Cys residues, which is called protein polysulfidation. Apart from the redox signaling regulatory mechanism, another plausible function of protein polysulfidation is providing protection for protein thiol residues against irreversible chemical modification caused by oxidants and electrophiles. Elucidation of the redox signaling regulatory mechanism of reactive persulfide species including small thiol molecules and thiol-containing proteins should lead to the development of new therapeutic strategies and drug discoveries for oxidative and electrophilic stress-related diseases.

Structural analysis of the core COMPASS family of histone H3K4 methylases from yeast to human

PubMed Central

Takahashi, Yoh-hei; Westfield, Gerwin H.; Oleskie, Austin N.; Trievel, Raymond C.; Shilatifard, Ali; Skiniotis, Georgios

2011-01-01

Histone H3 lysine 4 (H3K4) methylation is catalyzed by the highly evolutionarily conserved multiprotein complex known as Set1/COMPASS or MLL/COMPASS-like complexes from yeast to human, respectively. Here we have reconstituted fully functional yeast Set1/COMPASS and human MLL/COMPASS-like complex in vitro and have identified the minimum subunit composition required for histone H3K4 methylation. These subunits include the methyltransferase C-terminal SET domain of Set1/MLL, Cps60/Ash2L, Cps50/RbBP5, Cps30/WDR5, and Cps25/Dpy30, which are all common components of the COMPASS family from yeast to human. Three-dimensional (3D) cryo-EM reconstructions of the core yeast complex, combined with immunolabeling and two-dimensional (2D) EM analysis of the individual subcomplexes reveal a Y-shaped architecture with Cps50 and Cps30 localizing on the top two adjacent lobes and Cps60-Cps25 forming the base at the bottom. EM analysis of the human complex reveals a striking similarity to its yeast counterpart, suggesting a common subunit organization. The SET domain of Set1 is located at the juncture of Cps50, Cps30, and the Cps60-Cps25 module, lining the walls of a central channel that may act as the platform for catalysis and regulative processing of various degrees of H3K4 methylation. This structural arrangement suggested that COMPASS family members function as exo-methylases, which we have confirmed by in vitro and in vivo studies. PMID:22158900

Structural analysis of the core COMPASS family of histone H3K4 methylases from yeast to human.

PubMed

Takahashi, Yoh-hei; Westfield, Gerwin H; Oleskie, Austin N; Trievel, Raymond C; Shilatifard, Ali; Skiniotis, Georgios

2011-12-20

Histone H3 lysine 4 (H3K4) methylation is catalyzed by the highly evolutionarily conserved multiprotein complex known as Set1/COMPASS or MLL/COMPASS-like complexes from yeast to human, respectively. Here we have reconstituted fully functional yeast Set1/COMPASS and human MLL/COMPASS-like complex in vitro and have identified the minimum subunit composition required for histone H3K4 methylation. These subunits include the methyltransferase C-terminal SET domain of Set1/MLL, Cps60/Ash2L, Cps50/RbBP5, Cps30/WDR5, and Cps25/Dpy30, which are all common components of the COMPASS family from yeast to human. Three-dimensional (3D) cryo-EM reconstructions of the core yeast complex, combined with immunolabeling and two-dimensional (2D) EM analysis of the individual subcomplexes reveal a Y-shaped architecture with Cps50 and Cps30 localizing on the top two adjacent lobes and Cps60-Cps25 forming the base at the bottom. EM analysis of the human complex reveals a striking similarity to its yeast counterpart, suggesting a common subunit organization. The SET domain of Set1 is located at the juncture of Cps50, Cps30, and the Cps60-Cps25 module, lining the walls of a central channel that may act as the platform for catalysis and regulative processing of various degrees of H3K4 methylation. This structural arrangement suggested that COMPASS family members function as exo-methylases, which we have confirmed by in vitro and in vivo studies.

Analysis of the ontogeny of the murine humoral response to Neisseria meningitidis B capsular polysaccharide reveals levels of complexity relevant to vaccine development.

PubMed

Colino, J; Outschoorn, I

2001-12-15

Although purified capsular polysaccharide of Neisseria meningitidis group B (CpsB) is not immunogenic at any age, CpsB on the bacterial surface elicits antibody responses late in ontogeny. Therefore, a detailed analysis of the ontogeny of the murine anti-CpsB response to N. meningitidis could determine key parameters regarding the poor immunogenicity of CpsB. The effects of bacterial dose, hyperimmunization, age, and sex on the induction of primary and secondary anti-CpsB immunoglobulin isotype profiles were studied. It was demonstrated that the timing and repetition of immunization and of the bacterial dose have a marked differential effect on the primary induction of anti-CpsB immunoglobulin isotypes and on the ability to induce anti-CpsB antibody responses after subsequent rechallenge. It is noteworthy that the ontogeny of the response is related to the appearance of natural anti-CpsB antibodies, but this is not associated with the presence of CpsB cross-reactive antigens in the microflora.

High rate lithium-sulfur battery enabled by sandwiched single ion conducting polymer electrolyte

PubMed Central

Sun, Yubao; Li, Gai; Lai, Yuanchu; Zeng, Danli; Cheng, Hansong

2016-01-01

Lithium-sulfur batteries are highly promising for electric energy storage with high energy density, abundant resources and low cost. However, the battery technologies have often suffered from a short cycle life and poor rate stability arising from the well-known “polysulfide shuttle” effect. Here, we report a novel cell design by sandwiching a sp3 boron based single ion conducting polymer electrolyte film between two carbon films to fabricate a composite separator for lithium-sulfur batteries. The dense negative charges uniformly distributed in the electrolyte membrane inherently prohibit transport of polysulfide anions formed in the cathode inside the polymer matrix and effectively blocks polysulfide shuttling. A battery assembled with the composite separator exhibits a remarkably long cycle life at high charge/discharge rates. PMID:26898772

Carbon Disulfide Cosolvent Electrolytes for High-Performance Lithium Sulfur Batteries.

PubMed

Gu, Sui; Wen, Zhaoyin; Qian, Rong; Jin, Jun; Wang, Qingsong; Wu, Meifen; Zhuo, Shangjun

2016-12-21

Development of lithium sulfur (Li-S) batteries with high Coulombic efficiency and long cycle stability remains challenging due to the dissolution and shuttle of polysulfides in electrolyte. Here, a novel additive, carbon disulfide (CS 2 ), to the organic electrolyte is reported to improve the cycling performance of Li-S batteries. The cells with the CS 2 -additive electrolyte exhibit high Coulombic efficiency and long cycle stability, showing average Coulombic efficiency >99% and a capacity retention of 88% over the entire 300 cycles. The function of the CS 2 additive is 2-fold: (1) it inhibits the migration of long-chain polysulfides to the anode by forming complexes with polysulfides and (2) it passivates electrode surfaces by inducing the protective coatings on both the anode and the cathode.

Addendum to "Harmony of computational quantum chemistry and experimental chemistry: Comprehensive DFT studies, microsynthesis, and characterization of mustard gas polysulfide analogues" [J. Mol. Struct. (2018) 57-62

NASA Astrophysics Data System (ADS)

Saeidian, Hamid; Faraz, Sajjad Mousavi; Mirjafary, Zohreh; Babri, Mehran

2018-07-01

Recently, Blum from OPCW laboratory investigated HD, HS2, HS3 and higher polysulfides and their corresponding reactive intermediates by using Amsterdam Density Functional (ADF) calculations [22, 23]. In his presentation, he mentioned that analysis of MO energy levels for episulfonium ions of HD, HS2 and HS3 shows that the sulfur centered LUMOs for HS2 and HS3 are LUMO+1 for HD ion; and LUMOs energy levels of HS2 and HS3 are decreased by addition of polarizable sulfur atoms. He also showed that no four-membered sulfonium ion ring structures are formed for HS2, HS3 and higher polysulfides; and episulfonium ion is the only reactive intermediate for them.

Environmental Electrophiles: Protein Adducts, Modulation of Redox Signaling, and Interaction with Persulfides/Polysulfides.

PubMed

Kumagai, Yoshito; Abiko, Yumi

2017-01-17

Included among the many environmental electrophiles are aromatic hydrocarbon quinones formed during combustion of gasoline, crotonaldehyde in tobacco smoke, methylmercury accumulated in fish, cadmium contaminated in rice, and acrylamide in baked foods. These electrophiles can modify nucleophilic functions such as cysteine residues in proteins forming adducts and in the process activate cellular redox signal transduction pathways such as kinases and transcription factors. However, higher concentrations of electrophiles disrupt such signaling by nonselective covalent modification of cellular proteins. Persulfide/polysulfides produced by various enzymes appear to capture environmental electrophiles because of the formation of their sulfur adducts without electrophilicity. We therefore speculate that persulfide/polysulfides are candidates for the regulation of redox signal transduction pathways (e.g., cell survival, cell proliferation, and adaptive response) and toxicity during exposure to environmental electrophiles.

Polysulfide chemistry in sodium-sulfur batteries and related systems--a computational study by G3X(MP2) and PCM calculations.

PubMed

Steudel, Ralf; Steudel, Yana

2013-02-25

The sodium-sulfur (NAS) battery is a candidate for energy storage and load leveling in power systems, by using the reversible reduction of elemental sulfur by sodium metal to give a liquid mixture of polysulfides (Na(2)S(n)) at approximately 320°C. We investigated a large number of reactions possibly occurring in such sodium polysulfide melts by using density functional calculations at the G3X(MP2)/B3LYP/6-31+G(2df,p) level of theory including polarizable continuum model (PCM) corrections for two polarizable phases, to obtain geometric and, for the first time, thermodynamic data for the liquid sodium-sulfur system. Novel reaction sequences for the electrochemical reduction of elemental sulfur are proposed on the basis of their Gibbs reaction energies. We suggest that the primary reduction product of S(8) is the radical anion S(8)(˙-), which decomposes at the operating temperature of NAS batteries exergonically to the radicals S(2)(˙-) and S(3)(˙-) together with the neutral species S(6) and S(5), respectively. In addition, S(8)(˙-) is predicted to disproportionate exergonically to S(8) and S(8)(2-) followed by the dissociation of the latter into two S(4)(˙-) radical ions. By recombination reactions of these radicals various polysulfide dianions can in principle be formed. However, polysulfide dianions larger than S(4)(2-) are thermally unstable at 320°C and smaller dianions as well as radical monoanions dominate in Na(2)S(n) (n=2-5) melts instead. The reverse reactions are predicted to take place when the NAS battery is charged. We show that ion pairs of the types NaS(2)˙, NaS(n)(-), and Na(2)S(n) can be expected at least for n=2 and 3 in NAS batteries, but are unlikely in aqueous sodium polysulfide except at high concentrations. The structures of such radicals and anions with up to nine sulfur atoms are reported, because they are predicted to play a key role in the electrochemical reduction process. A large number of isomerization, disproportionation, and sulfurization reactions of polysulfide mono- and dianions have been investigated in the gas phase and in a polarizable continuum, and numerous reaction enthalpies as well as Gibbs energies are reported. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DNA Methylation Suppresses Expression of the Urea Cycle Enzyme Carbamoyl Phosphate Synthetase 1 (CPS1) in Human Hepatocellular Carcinoma

PubMed Central

Liu, Hongyan; Dong, Huijia; Robertson, Keith; Liu, Chen

2011-01-01

Carbamoyl phosphate synthetase 1 (CPS1) is a liver-specific, intramitochondrial, rate-limiting enzyme in the urea cycle. A previous study showed that CPS1 is the antigen for hepatocyte paraffin 1 antibody, a commonly used antibody in surgical pathology practice; and CPS1 expression appears to be down-regulated in liver cancer tissue and cell lines. The aim of this study is to understand how the CPS1 gene is regulated in liver carcinogenesis. In this report, we show that human hepatocellular carcinoma (HCC) cells do not express CPS1, whereas cultured human primary hepatocytes express abundant levels. In addition, CPS1 was silenced or down-regulated in liver tumor tissues compared with the matched noncancerous tissues. The expression of CPS1 in HCC cells was restored with a demethylation agent, 5-azacytidine. We show that two CpG dinucleotides, located near the transcription start site, and a CpG-rich region in the first intron were hypermethylated in HCC cells. The hypermethylation of the two CpG dinucleotides was also detected in HCC tumor tissues compared with noncancerous tissues. Further molecular analysis with mutagenesis indicated that the two CpG dinucleotides play a role in promoter activity of the CPS1 gene. In conclusion, our study demonstrates that DNA methylation is a key mechanism of silencing CPS1 expression in human HCC cells, and CPS1 gene hypermethylation of the two CpG dinucleotides is a potential biomarker for HCC. PMID:21281797

Security analysis of cyber-physical system

NASA Astrophysics Data System (ADS)

Li, Bo; Zhang, Lichen

2017-05-01

In recent years, Cyber-Physical System (CPS) has become an important research direction of academic circles and scientific and technological circles at home and abroad, is considered to be following the third wave of world information technology after the computer, the Internet. PS is a multi-dimensional, heterogeneous, deep integration of open systems, Involving the computer, communication, control and other disciplines of knowledge. As the various disciplines in the research theory and methods are significantly different, so the application of CPS has brought great challenges. This paper introduces the definition and characteristics of CPS, analyzes the current situation of CPS, analyzes the security threats faced by CPS, and gives the security solution for security threats. It also discusses CPS-specific security technology, to promote the healthy development of CPS in information security.

TREM-1 expression in craniopharyngioma and Rathke's cleft cyst: its possible implication for controversial pathology.

PubMed

Liu, Yi; Wang, Chao-Hu; Li, Dan-Ling; Zhang, Shi-Chao; Peng, Yu-Ping; Peng, Jun-Xiang; Song, Ye; Qi, Song-Tao; Pan, Jun

2016-08-02

Whether a mixed type of craniopharyngioma (CP) exists and whether papillary craniopharyngioma (pCP) is on a histopathological continuum with Rathke's cleft cyst (RCC) remain controversial. Herein, we examined the expression and localization of β-catenin, BRAF p.V600E (V600E), and triggering receptor expressed on myeloid cells-1 (TREM-1) in 58 samples including 20 pCPs, 26 adamantinomatous craniopharyngiomas (aCP), and 12 RCCs. Five aCPs were diagnosed with mixed type CPs and the remaining 21 cases were pure aCPs. Four of the 12 RCCs presented with significant squamous epithelium (SE). V600E immunoreactivity was observed in all pCPs in the cytoplasm, but not in the nuclei. aCPs and RCCs, including mixed type CP, did not express V600E. Nuclear β-catenin translocation was detected exclusively in aCPs. TREM-1 was expressed in pCPs. Additionally, TREM-1 expression was detected in the SE of 5 "mixed type" CPs, while it was absent in pure aCPs. TREM-1 was expressed in 4 RCCs with SE, but not in the remaining 8 RCCs. TREM-1 mRNA levels were compared in cultured pCP and aCP cells. TREM-1 mRNA level was significantly (p < 0.001; up to 4.045 fold) higher in pCPs than in aCPs. Western blotting revealed a significantly (p < 0.001; up to 7.19 fold) lower level of TREM-1 expression in aCP cells compared to that in pCP cells. Our findings further supported that RCC and pCP may represent two ends of a morphological spectrum. A variant showing overlapping histological features of aCP and pCP should not be considered as a mixed type.

The Transcriptional Regulator CpsY Is Important for Innate Immune Evasion in Streptococcus pyogenes

PubMed Central

Vega, Luis A.; Valdes, Kayla M.; Sundar, Ganesh S.; Belew, Ashton T.; Islam, Emrul; Berge, Jacob; Curry, Patrick; Chen, Steven

2016-01-01

ABSTRACT As an exclusively human pathogen, Streptococcus pyogenes (the group A streptococcus [GAS]) has specifically adapted to evade host innate immunity and survive in multiple tissue niches, including blood. GAS can overcome the metabolic constraints of the blood environment and expresses various immunomodulatory factors necessary for survival and immune cell resistance. Here we present our investigation of one such factor, the predicted LysR family transcriptional regulator CpsY. The encoding gene, cpsY, was initially identified as being required for GAS survival in a transposon-site hybridization (TraSH) screen in whole human blood. CpsY is homologous with transcriptional regulators of Streptococcus mutans (MetR), Streptococcus iniae (CpsY), and Streptococcus agalactiae (MtaR) that regulate methionine transport, amino acid metabolism, resistance to neutrophil-mediated killing, and survival in vivo. Our investigation indicated that CpsY is involved in GAS resistance to innate immune cells of its human host. However, GAS CpsY does not manifest the in vitro phenotypes of its homologs in other streptococcal species. GAS CpsY appears to regulate a small set of genes that is markedly different from the regulons of its homologs. The differential expression of these genes depends on the growth medium, and CpsY modestly influences their expression. The GAS CpsY regulon includes known virulence factors (mntE, speB, spd, nga [spn], prtS [SpyCEP], and sse) and cell surface-associated factors of GAS (emm1, mur1.2, sibA [cdhA], and M5005_Spy0500). Intriguingly, the loss of CpsY in GAS does not result in virulence defects in murine models of infection, suggesting that CpsY function in immune evasion is specific to the human host. PMID:27993974

Streptococcus iniae cpsG alters capsular carbohydrate composition and is a cause of serotype switching in vaccinated fish.

PubMed

Heath, Candice; Gillen, Christine M; Chrysanthopoulos, Panagiotis; Walker, Mark J; Barnes, Andrew C

2016-09-25

Streptococcus iniae causes septicaemia and meningitis in marine and freshwater fish wherever they are farmed in warm-temperate and tropical regions. Although serotype specific, vaccination with bacterins (killed bacterial cultures) is largely successful and vaccine failure occurs only occasionally through emergence of new capsular serotypes. Previously we showed that mutations in vaccine escapes are restricted to a limited repertoire of genes within the 20-gene capsular polysaccharide (cps) operon. cpsG, a putative UDP-galactose 4-epimerase, has three sequence types based on the insertion or deletion of the three amino acids leucine, serine and lysine in the substrate binding site of the protein. To elucidate the role of cpsG in capsular polysaccharide (CPS) biosynthesis and capsular composition, we first prepared isogenic knockout and complemented mutants of cpsG by allelic exchange mutagenesis. Deletion of cpsG resulted in changes to colony morphology and cell buoyant density, and also significantly decreased galactose content relative to glucose in the capsular polysaccharide as determined by GC-MS, consistent with epimerase activity of CpsG. There was also a metabolic penalty of cpsG knockout revealed by slower growth in complex media, and reduced proliferation in whole fish blood. Moreover, whilst antibodies raised in fish against the wild type cross-reacted in whole cell and cps ELISA, they did not cross-opsonise the mutant in a peripheral blood neutrophil opsonisation assay, consistent with reported vaccine escape. We have shown here that mutation in cpsG results in altered CPS composition and this in turn results in poor cross-opsonisation that explains some of the historic vaccination failure on fish farms in Australia. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

Co(III)EDTA- Reduction by Desulfovibrio vulgaris and Propagation of Reactions Involving Dissolved Sulfide and Polysulfides.

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

Blessing, T.C.; B.W. Wielinga; M.J. Morra

2001-04-15

The migration of 60Co is driven by Co(III)EDTA- complexes. Here we document the bacterial mediated reduction of Co(III) to Co(II)EDTA2- complexes, which are far less mobile within the environment. Additionally, we demonstrate that sulfate promotes reduction via production of reactive polysulfides rather than acting as a competitive electron acceptor.

Inorganic hydrogen polysulfides: chemistry, chemical biology and detection.

PubMed

Liu, Heng; Radford, Miles N; Yang, Chun-Tao; Chen, Wei; Xian, Ming

2018-04-18

Recent studies suggest that inorganic hydrogen polysulfides (H 2 S n , n ≥ 2) play important regulatory roles in redox biology. Modulation of their cellular levels could have potential therapeutic value. This review article focuses on our current understanding of the biosynthesis, biofunctions, fundamental physical/chemical properties, detection methods and delivery techniques of H 2 S n . © 2018 The British Pharmacological Society.

Effect of Hydrofluoroether Cosolvent Addition on Li Solvation in Acetonitrile-Based Solvate Electrolytes and Its Influence on S Reduction in a Li–S Battery

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

See, Kimberly A.; Wu, Heng -Liang; Lau, Kah Chun

Li-S batteries are a promising next-generation battery technology. Due to the formation of soluble polysulfides during cell operation, the electrolyte composition of the cell plays an active role in directing the formation and speciation of the soluble lithium polysulfides. Recently, new classes of electrolytes termed "solvates" that contain stoichiometric quantities of salt and solvent and form a liquid at room temperature have been explored due to their sparingly solvating properties with respect to polysulfides. The viscosity of the solvate electrolytes is understandably high limiting their viability; however, hydrofluoroether cosolvents, thought to be inert to the solvate structure itself, can bemore » introduced to reduce viscosity and enhance diffusion. Nazar and co-workers previously reported that addition of 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE) to the LiTFSI in acetonitrile solvate, (MeCN) 2-LiTFSI, results in enhanced capacity retention compared to the neat solvate. Here, we evaluate the effect of TTE addition on both the electrochemical behavior of the Li-S cell and the solvation structure of the (MeCN) 2-LiTFSI electrolyte. Contrary to previous suggestions, Raman and NMR spectroscopy coupled with ab initio molecular dynamics simulations show that TTE coordinates to Li + at the expense of MeCN coordination, thereby producing a higher content of free MeCN, a good polysulfide solvent, in the electrolyte. Furthermore, the electrolytes containing a higher free MeCN content facilitate faster polysulfide formation kinetics during the electrochemical reduction of S in a Li-S cell likely as a result of the solvation power of the free MeCN.« less

Long-Chain Polysulfide Retention at the Cathode of Li–S Batteries

DOE PAGES

Kamphaus, Ethan P.; Balbuena, Perla B.

2016-02-10

Lithium–sulfur batteries present a complex interconnected chemistry where the three components—anode, electrolyte, and cathode—strongly interact with each other. One of the main issues associated with these interactions is the dissolution in the electrolyte solution of part of the sulfur reduction products (mainly long-chain polysulfides) during the discharge reactions at the cathode. These dissolved species can migrate and react at the anode surface producing undesired insulating films. A potential solution to mitigate this problem is to resort to additional materials which can act as anchors of the soluble species thus avoiding their migration. Density functional theory and ab initio molecular dynamicsmore » simulations are employed to investigate the ability of certain substrates to retain long-chain polysulfides (Li 2S 6 and Li 2S 8) at their surfaces in the presence of a pure solvent or a lithiated solution. Nanopores of graphene are first tested because the cathode is usually a mix of sulfur and carbon. Then, MoS 2 and Mo-doped graphene are evaluated because of the well-known Mo–S affinity. Finally, a material which has been reported successful in experimental studies, MnO 2, is analyzed and compared with another oxide surface, Fe 2O 3. Adsorption energies of the polysulfides to the surfaces and the detailed interactions of the Li ions and S atoms with the substrate are characterized via charge and geometric analyses. Both the Mo-containing materials and the oxides adsorb the polysulfides much more strongly than graphene nanopores do. However, some of these surfaces are found to be excessively reactive. Thus, a balance between affinity for S and moderate surface reactivity is found as a promising guideline for designing these materials.« less

A core–shell electrode for dynamically and statically stable Li–S battery chemistry

DOE PAGES

Chung, Sheng-Heng; Chang, Chi-Hao; Manthiram, Arumugam

2016-08-17

Sulfur is an appealing cathode material for establishing advanced lithium batteries as it offers a high theoretical capacity of 1675 mA h g -1 at low material and operating costs. However, the lithium–sulfur (Li–S) electrochemical cells face several formidable challenges arising from both the materials chemistry (e.g., low electrochemical utilization of sulfur and severe polysulfide diffusion) and battery chemistry (e.g., dynamic and static instability and low sulfur loadings). Here in this study, we present the design of a core–shell cathode with a pure sulfur core shielded within a conductive shell-shaped electrode. The new electrode configuration allows Li–S cells to loadmore » with a high amount of sulfur (sulfur loadings of up to 30 mg cm -2 and sulfur content approaching 70 wt%). The core–shell cathodes demonstrate a superior dynamic and static electrochemical stability in Li–S cells. The high-loading cathodes exhibit (i) a high sulfur utilization of up to 97% at C/20–C/2 rates and (ii) a low self-discharge during long-term cell storage for a three-month rest period and at different cell-storage conditions. Finally, a polysulfide-trap cell configuration is designed to evidence the eliminations of polysulfide diffusion and to investigate the relationship between the electrode configuration and electrochemical characteristics. Finally, the comprehensive analytical results based on the high-loading cathodes suggest that (i) the core–shell cathode is a promising solution for designing highly reversible Li–S cells and (ii) the polysulfide-trap cell configuration is a viable approach to qualitatively evaluating the presence or absence of polysulfide diffusion.« less

Effect of Hydrofluoroether Cosolvent Addition on Li Solvation in Acetonitrile-Based Solvate Electrolytes and Its Influence on S Reduction in a Li–S Battery

DOE PAGES

See, Kimberly A.; Wu, Heng -Liang; Lau, Kah Chun; ...

2016-11-16

Li-S batteries are a promising next-generation battery technology. Due to the formation of soluble polysulfides during cell operation, the electrolyte composition of the cell plays an active role in directing the formation and speciation of the soluble lithium polysulfides. Recently, new classes of electrolytes termed "solvates" that contain stoichiometric quantities of salt and solvent and form a liquid at room temperature have been explored due to their sparingly solvating properties with respect to polysulfides. The viscosity of the solvate electrolytes is understandably high limiting their viability; however, hydrofluoroether cosolvents, thought to be inert to the solvate structure itself, can bemore » introduced to reduce viscosity and enhance diffusion. Nazar and co-workers previously reported that addition of 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE) to the LiTFSI in acetonitrile solvate, (MeCN) 2-LiTFSI, results in enhanced capacity retention compared to the neat solvate. Here, we evaluate the effect of TTE addition on both the electrochemical behavior of the Li-S cell and the solvation structure of the (MeCN) 2-LiTFSI electrolyte. Contrary to previous suggestions, Raman and NMR spectroscopy coupled with ab initio molecular dynamics simulations show that TTE coordinates to Li + at the expense of MeCN coordination, thereby producing a higher content of free MeCN, a good polysulfide solvent, in the electrolyte. Furthermore, the electrolytes containing a higher free MeCN content facilitate faster polysulfide formation kinetics during the electrochemical reduction of S in a Li-S cell likely as a result of the solvation power of the free MeCN.« less

Effect of Hydrofluoroether Cosolvent Addition on Li Solvation in Acetonitrile-Based Solvate Electrolytes and Its Influence on S Reduction in a Li-S Battery.

PubMed

See, Kimberly A; Wu, Heng-Liang; Lau, Kah Chun; Shin, Minjeong; Cheng, Lei; Balasubramanian, Mahalingam; Gallagher, Kevin G; Curtiss, Larry A; Gewirth, Andrew A

2016-12-21

Li-S batteries are a promising next-generation battery technology. Due to the formation of soluble polysulfides during cell operation, the electrolyte composition of the cell plays an active role in directing the formation and speciation of the soluble lithium polysulfides. Recently, new classes of electrolytes termed "solvates" that contain stoichiometric quantities of salt and solvent and form a liquid at room temperature have been explored due to their sparingly solvating properties with respect to polysulfides. The viscosity of the solvate electrolytes is understandably high limiting their viability; however, hydrofluoroether cosolvents, thought to be inert to the solvate structure itself, can be introduced to reduce viscosity and enhance diffusion. Nazar and co-workers previously reported that addition of 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether (TTE) to the LiTFSI in acetonitrile solvate, (MeCN) 2 -LiTFSI, results in enhanced capacity retention compared to the neat solvate. Here, we evaluate the effect of TTE addition on both the electrochemical behavior of the Li-S cell and the solvation structure of the (MeCN) 2 -LiTFSI electrolyte. Contrary to previous suggestions, Raman and NMR spectroscopy coupled with ab initio molecular dynamics simulations show that TTE coordinates to Li + at the expense of MeCN coordination, thereby producing a higher content of free MeCN, a good polysulfide solvent, in the electrolyte. The electrolytes containing a higher free MeCN content facilitate faster polysulfide formation kinetics during the electrochemical reduction of S in a Li-S cell likely as a result of the solvation power of the free MeCN.

Key bioactive reaction products of the NO/H2S interaction are S/N-hybrid species, polysulfides, and nitroxyl

PubMed Central

Cortese-Krott, Miriam M.; Kuhnle, Gunter G. C.; Dyson, Alex; Fernandez, Bernadette O.; Grman, Marian; DuMond, Jenna F.; Barrow, Mark P.; McLeod, George; Nakagawa, Hidehiko; Ondrias, Karol; Nagy, Péter; King, S. Bruce; Saavedra, Joseph E.; Keefer, Larry K.; Singer, Mervyn; Kelm, Malte; Butler, Anthony R.; Feelisch, Martin

2015-01-01

Experimental evidence suggests that nitric oxide (NO) and hydrogen sulfide (H2S) signaling pathways are intimately intertwined, with mutual attenuation or potentiation of biological responses in the cardiovascular system and elsewhere. The chemical basis of this interaction is elusive. Moreover, polysulfides recently emerged as potential mediators of H2S/sulfide signaling, but their biosynthesis and relationship to NO remain enigmatic. We sought to characterize the nature, chemical biology, and bioactivity of key reaction products formed in the NO/sulfide system. At physiological pH, we find that NO and sulfide form a network of cascading chemical reactions that generate radical intermediates as well as anionic and uncharged solutes, with accumulation of three major products: nitrosopersulfide (SSNO−), polysulfides, and dinitrososulfite [N-nitrosohydroxylamine-N-sulfonate (SULFI/NO)], each with a distinct chemical biology and in vitro and in vivo bioactivity. SSNO− is resistant to thiols and cyanolysis, efficiently donates both sulfane sulfur and NO, and potently lowers blood pressure. Polysulfides are both intermediates and products of SSNO− synthesis/decomposition, and they also decrease blood pressure and enhance arterial compliance. SULFI/NO is a weak combined NO/nitroxyl donor that releases mainly N2O on decomposition; although it affects blood pressure only mildly, it markedly increases cardiac contractility, and formation of its precursor sulfite likely contributes to NO scavenging. Our results unveil an unexpectedly rich network of coupled chemical reactions between NO and H2S/sulfide, suggesting that the bioactivity of either transmitter is governed by concomitant formation of polysulfides and anionic S/N-hybrid species. This conceptual framework would seem to offer ample opportunities for the modulation of fundamental biological processes governed by redox switching and sulfur trafficking. PMID:26224837

Polysulfide Binding to Several Nanoscale Magnéli Phases Synthesized in Carbon for Long-Life Lithium-Sulfur Battery Cathodes.

PubMed

Zubair, Usman; Amici, Julia; Francia, Carlotta; McNulty, David; Bodoardo, Silvia; O'Dwyer, Colm

2018-06-11

In Li-S batteries, it is important to ensure efficient reversible conversion of sulfur to lithium polysulfide (LiPS). Shuttling effects caused by LiPS dissolution can lead to reduced performance and cycle life. Although carbon materials rely on physical trapping of polysulfides, polar oxide surfaces can chemically bind LiPS to improve the stability of sulfur cathodes. We show a simple synthetic method that allows high sulfur loading into mesoporous carbon preloaded with spatially localized nanoparticles of several Magnéli-phase titanium oxide (Ti n O 2n-1 ). This material simultaneously suppresses polysulfide shuttling phenomena by chemically binding Li polysulfides onto several Magnéli-phase surfaces in a single cathode and ensures physical confinement of sulfur and LiPS. The synergy between chemical immobilization of significant quantities of LiPS at the surface of several Ti n O 2n-1 phases and physical entrapment results in coulombically efficient high-rate cathodes with long cycle life and high capacity. These cathodes function efficiently at low electrolyte-to-sulfur ratios to provide high gravimetric and volumetric capacities in comparison with their highly porous carbon counterparts. Assembled coin cells have an initial discharge capacity of 1100 mAh g -1 at 0.1C and maintain a reversible capacity of 520 mAh g -1 at 0.2C for more than 500 cycles. Even at 1C, the cell loses only 0.06 % per cycle for 1000 cycles with a coulombic efficiency close to 99 %. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Clinical pharmacists: The major support to Indian healthcare system in near future

PubMed Central

Deshpande, Prasanna R.; Vantipalli, Raghuram; Chaitanya Lakshmi, C. H.; Rao, E. Jagadeswara; Regmi, Bishnu; Ahad, Abdul; Nirojini, P. Sharmila

2015-01-01

Pharmacy practice is still in the initial stages of development in India, but launching of Doctor of Pharmacy (PharmD) study program has brought serious discussions about clinical pharmacy in the country. As the profession is in budding stage in the country, the patients, physicians, nurses, other healthcare providers, recruiters in pharmaceutical industries, prospective students, and their parents have numerous questions about this profession and study course. The objective of this article is to create awareness about clinical pharmacy services (CPS) and to introduce the role of clinical pharmacists (CPs). After reading this article, one will know about the usefulness of CPs in the Indian healthcare system against the current flaws in the system. The article describes the role of CPs in the hospitals, in research, in pharmaceutical/contract research companies, in community service and it also tells about the related myths and facts. Prospective job opportunities for CPs, present challenges and the possible solutions are elaborated as well. In conclusion, CPs are going to be the major support to the Indian healthcare system in near future; the reasons being (1) CPS are beneficial in many ways to improve healthcare; CPS have already proved their importance in western countries (2) India was never officially and efficiently exposed to CPS; so launching of CPS shall revolutionize the country's healthcare scenario. PMID:26229349

Cross-national comparisons of complex problem-solving strategies in two microworlds.

PubMed

Güss, C Dominik; Tuason, Ma Teresa; Gerhard, Christiane

2010-04-01

Research in the fields of complex problem solving (CPS) and dynamic decision making using microworlds has been mainly conducted in Western industrialized countries. This study analyzes the CPS process by investigating thinking-aloud protocols in five countries. Participants were 511 students from Brazil, Germany, India, the Philippines, and the United States who worked on two microworlds. On the basis of cultural-psychological theories, specific cross-national differences in CPS strategies were hypothesized. Following theories of situatedness of cognition, hypotheses about the specific frequency of problem-solving strategies in the two microworlds were developed. Results of the verbal protocols showed (a) modification of the theoretical CPS model, (b) task dependence of CPS strategies, and (c) cross-national differences in CPS strategies. Participants' CPS processes were particularly influenced by country-specific problem-solving strategies. Copyright © 2009 Cognitive Science Society, Inc.

Exploring Business Students' Creative Problem-Solving Preferences

ERIC Educational Resources Information Center

Titus, Philip A.; Koppitsch, Steven

2018-01-01

Past research has established the importance of problem solving to business success. The authors explored the creative problem-solving (CPS) preferences of business students, addressing two primary issues: (a) Do CPS preferences vary across CPS stages and tasks? And (b) Do CPS preferences regarding collaboration and delegation vary by stage?…

Vertically-aligned carbon nanotubes on aluminum as a light-weight positive electrode for lithium-polysulfide batteries.

PubMed

Liatard, S; Benhamouda, K; Fournier, A; Ramos, R; Barchasz, C; Dijon, J

2015-05-04

A light-weight, high specific surface current collector made of vertically-aligned carbon nanotubes grown on an aluminum substrate was fabricated and studied as a positive electrode in a semi-liquid lithium/polysulfide battery. This simple system delivered stable capacities over 1000 mA h gS(-1) and 2 mA h cm(-2) with almost no capacity loss over 50 cycles.

Effects of Anion Mobility on Electrochemical Behaviors of Lithium–Sulfur Batteries

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

Han, Kee Sung; Chen, Junzheng; Cao, Ruiguo

The electrolyte is a crucial component of lithium-sulfur (Li-S) batteries, as it controls polysulfide dissolution, charge shuttling processes, and solid-electrolyte interphase (SEI) layer formation. Experimentally, the overall performance of Li-S batteries varies with choice of solvent system and Li-salt used in the electrolyte, and a lack of predictive understanding about the effects of individual electrolyte components inhibits the rational design of electrolytes for Li-S batteries. Here we analyze the role of the counter anions of common Li salts (such as TfO-, FSI-, TFSI-, and TDI-) when dissolved in DOL/DME (1:1 vol.) for use in Li-S batteries. The evolution of ion-ionmore » and ion-solvent interactions due to vari-ous anions was analyzed using 17O NMR and pulsed-field gradient (PFG) NMR and then correlated with electrochemi-cal performance in Li-S cells. These data reveal that the for-mation of the passivation layer on the anode and the loss of active materials from the cathode (evidenced by polysulfide dissolution) are related to anion mobility and affinity with lithium polysulfide, respectively. For future electrolyte de-sign, anions with lower mobility and weaker interactions with lithium polysulfides may be superior candidates for increasing the long-term stability of Li-S batteries.« less

The La{sub 2}S{sub 3}-LaS{sub 2} system: Thermodynamic and kinetic study

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

Vasilyeva, I.G., E-mail: kamarz@niic.nsc.r; Nikolaev, R.E.

2010-08-15

A detailed thermodynamic study of the LaS{sub 2}-La{sub 2}S{sub 3} system in the temperature range 350-1000 {sup o}C was performed, starting from high quality crystals LaS{sub 2} as the highest polysulfide in the system, and using a sensitive static tensimetric method with a quartz Bourdon gauge and a membrane as a null-point instrument. The p{sub S}-T-x diagram obtained has shown that the phase region covering the composition between LaS{sub 2} and La{sub 2}S{sub 3}, which was previously described as a single grossly nonstoichiometric phase, consists of three discrete stoichiometric phases, LaS{sub 2.00}, LaS{sub 1.91}, and LaS{sub 1.76}, where compositions couldmore » be determined with an accuracy of {+-}0.01 f.u. The thermodynamic characteristics of evaporation of the polysulfides as well as standard heat of LaS{sub 2} formation were calculated. The role of kinetics in the formation of ordered superstructures of sulfur-poorer polysulfides with different formal concentration of vacancies is considered. - Graphical abstract: The p{sub S}-T stability fields for La-polysulfides in the concentration range between LaS{sub 2} and La{sub 2}S{sub 3}.« less

Functional characterization of ent-copalyl diphosphate synthase from Andrographis paniculata with putative involvement in andrographolides biosynthesis.

PubMed

Shen, Qinqin; Li, Lixia; Jiang, Yu; Wang, Qiang

2016-01-01

To characterize the ent-copalyl diphosphate (ent-CPP) synthase involved in the biosynthetic pathway of andrographolides in a medicinal plant, Andrographis paniculata. The ent-CPP synthase (ent-CPS) gene was cloned from A. paniculata and its encoded ApCPS was demonstrated to react with (E,E,E)-geranylgeranyl diphosphate to form ent-CPP through recombinant expression in Escherichia coli. Site-directed mutagenesis of the Asp to Ala in the conserved DXDD motif of ApCPS resulted in loss of function. One Arg is located in the conserved position close to DXDD motif indicating the involvement of ApCPS in specialized metabolism. In addition, RT-PCR analysis revealed that ApCPS was expressed in all tissues of A. paniculata at all growth stages, which is consistent with andrographolides accumulating in these organs. Methyl jasmonate induced ApCPS gene expression, matching inducible accumulation of andrographolides in vivo. ApCPS is the first ent-CPS characterized in A. paniculata and is suggested to be involved in biosynthesis of andrographolides that have high pharmaceutical values.

Making Full Use of the Longitudinal Design of the Current Population Survey: Methods for Linking Records Across 16 Months *

PubMed Central

Drew, Julia A. Rivera; Flood, Sarah; Warren, John Robert

2015-01-01

Data from the Current Population Survey (CPS) are rarely analyzed in a way that takes advantage of the CPS’s longitudinal design. This is mainly because of the technical difficulties associated with linking CPS files across months. In this paper, we describe the method we are using to create unique identifiers for all CPS person and household records from 1989 onward. These identifiers—available along with CPS basic and supplemental data as part of the on-line Integrated Public Use Microdata Series (IPUMS)—make it dramatically easier to use CPS data for longitudinal research across any number of substantive domains. To facilitate the use of these new longitudinal IPUMS-CPS data, we also outline seven different ways that researchers may choose to link CPS person records across months, and we describe the sample sizes and sample retention rates associated with these seven designs. Finally, we discuss a number of unique methodological challenges that researchers will confront when analyzing data from linked CPS files. PMID:26113770

Nano-sized and micro-sized polystyrene particles affect phagocyte function

PubMed Central

Prietl, B.; Meindl, C.; Roblegg, E.; Pieber, T. R.; Lanzer, G.; Fröhlich, E.

2015-01-01

Adverse effect of nanoparticles may include impairment of phagocyte function. To identify the effect of nanoparticle size on uptake, cytotoxicity, chemotaxis, cytokine secretion, phagocytosis, oxidative burst, nitric oxide production and myeloperoxidase release, leukocytes isolated from human peripheral blood, monocytes and macrophages were studied. Carboxyl polystyrene (CPS) particles in sizes between 20 and 1,000 nm served as model particles. Twenty nanometers CPS particles were taken up passively, while larger CPS particles entered cells actively and passively. Twenty nanometers CPS were cytotoxic to all phagocytes, ≥500 nm CPS particles only to macrophages. Twenty nanometers CPS particles stimulated IL-8 secretion in human monocytes and induced oxidative burst in monocytes. Five hundred nanometers and 1,000 nm CPS particles stimulated IL-6 and IL-8 secretion in monocytes and macrophages, chemotaxis towards a chemotactic stimulus of monocytes and phagocytosis of bacteria by macrophages and provoked an oxidative burst of granulocytes. At very high concentrations, CPS particles of 20 and 500 nm stimulated myeloperoxidase release of granulocytes and nitric oxide generation in macrophages. Cytotoxic effect could contribute to some of the observed effects. In the absence of cytotoxicity, 500 and 1,000 nm CPS particles appear to influence phagocyte function to a greater extent than particles in other sizes. PMID:24292270

Targeting CPS1 in the treatment of Carbamoyl phosphate synthetase 1 (CPS1) deficiency, a urea cycle disorder.

PubMed

Diez-Fernandez, Carmen; Häberle, Johannes

2017-04-01

Carbamoyl phosphate synthetase 1 (CPS1) deficiency (CPS1D) is a rare autosomal recessive urea cycle disorder (UCD), which can lead to life-threatening hyperammonemia. Unless promptly treated, it can result in encephalopathy, coma and death, or intellectual disability in surviving patients. Over recent decades, therapies for CPS1D have barely improved leaving the management of these patients largely unchanged. Additionally, in many cases, current management (protein-restriction and supplementation with citrulline and/or arginine and ammonia scavengers) is insufficient for achieving metabolic stability, highlighting the importance of developing alternative therapeutic approaches. Areas covered: After describing UCDs and CPS1D, we give an overview of the structure- function of CPS1. We then describe current management and potential novel treatments including N-carbamoyl-L-glutamate (NCG), pharmacological chaperones, and gene therapy to treat hyperammonemia. Expert opinion: Probably, the first novel CPS1D therapies to reach the clinics will be the already commercial substance NCG, which is the standard treatment for N-acetylglutamate synthase deficiency and has been proven to rescue specific CPS1D mutations. Pharmacological chaperones and gene therapy are under development too, but these two technologies still have key challenges to be overcome. In addition, current experimental therapies will hopefully add further treatment options.

Nano-sized and micro-sized polystyrene particles affect phagocyte function.

PubMed

Prietl, B; Meindl, C; Roblegg, E; Pieber, T R; Lanzer, G; Fröhlich, E

2014-02-01

Adverse effect of nanoparticles may include impairment of phagocyte function. To identify the effect of nanoparticle size on uptake, cytotoxicity, chemotaxis, cytokine secretion, phagocytosis, oxidative burst, nitric oxide production and myeloperoxidase release, leukocytes isolated from human peripheral blood, monocytes and macrophages were studied. Carboxyl polystyrene (CPS) particles in sizes between 20 and 1,000 nm served as model particles. Twenty nanometers CPS particles were taken up passively, while larger CPS particles entered cells actively and passively. Twenty nanometers CPS were cytotoxic to all phagocytes, ≥500 nm CPS particles only to macrophages. Twenty nanometers CPS particles stimulated IL-8 secretion in human monocytes and induced oxidative burst in monocytes. Five hundred nanometers and 1,000 nm CPS particles stimulated IL-6 and IL-8 secretion in monocytes and macrophages, chemotaxis towards a chemotactic stimulus of monocytes and phagocytosis of bacteria by macrophages and provoked an oxidative burst of granulocytes. At very high concentrations, CPS particles of 20 and 500 nm stimulated myeloperoxidase release of granulocytes and nitric oxide generation in macrophages. Cytotoxic effect could contribute to some of the observed effects. In the absence of cytotoxicity, 500 and 1,000 nm CPS particles appear to influence phagocyte function to a greater extent than particles in other sizes.

The Streptococcus iniae transcriptional regulator CpsY is required for protection from neutrophil-mediated killing and proper growth in vitro.

PubMed

Allen, Jonathan P; Neely, Melody N

2011-11-01

The ability of a pathogen to metabolically adapt to the local environment for optimal expression of virulence determinants is a continued area of research. Orthologs of the Streptococcus iniae LysR family regulator CpsY have been shown to regulate methionine biosynthesis and uptake pathways but appear to influence expression of several virulence genes as well. An S. iniae mutant with an in-frame deletion of cpsY (ΔcpsY mutant) is highly attenuated in a zebrafish infection model. The ΔcpsY mutant displays a methionine-independent growth defect in serum, which differs from the methionine-dependent defect observed for orthologous mutants of Streptococcus mutans and Streptococcus agalactiae. On the contrary, the ΔcpsY mutant can grow in excess of the wild type (WT) when supplemented with proteose peptone, suggesting an inability to properly regulate growth. CpsY is critical for protection of S. iniae from clearance by neutrophils in whole blood but is dispensable for intracellular survival in macrophages. Susceptibility of the ΔcpsY mutant to killing in whole blood is not due to a growth defect, because inhibition of neutrophil phagocytosis rescues the mutant to WT levels. Thus, CpsY appears to have a pleiotropic regulatory role for S. iniae, integrating metabolism and virulence. Furthermore, S. iniae provides a unique model to investigate the paradigm of CpsY-dependent regulation during systemic streptococcal infection.

The Streptococcus iniae Transcriptional Regulator CpsY Is Required for Protection from Neutrophil-Mediated Killing and Proper Growth In Vitro ▿

PubMed Central

Allen, Jonathan P.; Neely, Melody N.

2011-01-01

The ability of a pathogen to metabolically adapt to the local environment for optimal expression of virulence determinants is a continued area of research. Orthologs of the Streptococcus iniae LysR family regulator CpsY have been shown to regulate methionine biosynthesis and uptake pathways but appear to influence expression of several virulence genes as well. An S. iniae mutant with an in-frame deletion of cpsY (ΔcpsY mutant) is highly attenuated in a zebrafish infection model. The ΔcpsY mutant displays a methionine-independent growth defect in serum, which differs from the methionine-dependent defect observed for orthologous mutants of Streptococcus mutans and Streptococcus agalactiae. On the contrary, the ΔcpsY mutant can grow in excess of the wild type (WT) when supplemented with proteose peptone, suggesting an inability to properly regulate growth. CpsY is critical for protection of S. iniae from clearance by neutrophils in whole blood but is dispensable for intracellular survival in macrophages. Susceptibility of the ΔcpsY mutant to killing in whole blood is not due to a growth defect, because inhibition of neutrophil phagocytosis rescues the mutant to WT levels. Thus, CpsY appears to have a pleiotropic regulatory role for S. iniae, integrating metabolism and virulence. Furthermore, S. iniae provides a unique model to investigate the paradigm of CpsY-dependent regulation during systemic streptococcal infection. PMID:21911465

Rate of Decay in Proportion of Condom Protected Sex Acts among Adolescents Following Participation in an HIV Risk-Reduction Intervention

PubMed Central

DiClemente, Ralph J.; Brown, Jennifer L.; Sales, Jessica M.; Rose, Eve S.

2013-01-01

Objective HIV risk-reduction interventions have demonstrated efficacy in enhancing the proportion of condom protected sex acts (CPS) among diverse populations. While post-intervention exposure increases in CPS are often observed, there is scant empirical data quantifying decay of intervention efficacy (declines in CPS following cessation of the intervention among participants reporting an initial post-intervention increase in CPS). Thus, the objective of this study was to quantify the rate of decay in intervention efficacy over a 24-month follow-up. Design African-American adolescent females (ages 14–20; N = 349) completed a baseline ACASI, participated in an HIV risk-reduction intervention, and were assessed at 6-month intervals for 24-months post-intervention. Intervention efficacy was conceptualized as an increase in participants’ CPS relative to baseline. Methods Analyses focused on the subset of participants who reported an initial increase in CPS from baseline to the 6-month post-intervention assessment (n = 121) to quantify the rate of decay in intervention efficacy over a 24-month follow-up period. Results CPS increased markedly from baseline to 6-month follow-up assessment. However, from 6- to 12-months, a marked decline in CPS was observed. Further CPS declines, though not statistically significant, were observed from 12- to 18-months and 18- to 24-months. Cumulative reductions in CPS over the entire 24-month follow-up resulted in no statistical difference between baseline and 24-month follow-up; indicative of a non-significant intervention effect at 24-month assessment. Conclusions Innovative post-intervention optimization strategies are needed to minimize CPS decay over protracted time periods by reinforcing, sustaining, and potentially amplifying initial gains in condom use. PMID:23673893

Consensus guidelines: improving the delivery of clinical preventive services.

PubMed

Ayres, Cynthia G; Griffith, Hurdis M

2008-01-01

Medical directors from the largest competing health plans in the state came together in a noncompetitive way to collaborate on improving the delivery of clinical preventive service (CPS) among their provider base. They identified one consistent set of CPS guidelines based on U.S. Preventive Services Task Force recommendations, the health plan consensus guidelines (HPCG), that they could endorse as priority for guideline implementation. The purposes of this study were to assess clinicians' knowledge and use of CPS recommendations as a guide to delivering preventive care services to their patients and, most importantly, to test the effectiveness of providing the HPCG to clinicians in an effort to increase knowledge and use of CPS guidelines. Within-subjects repeated-measures design was used. We hypothesized an increase in clinician's knowledge and use of CPS after the provision of the HPCG. Survey methodology, including two surveys that assessed clinicians' knowledge and use of CPS in practice, was used. Health plan clinician databases were obtained from the health plans that participated in the development of the HPCG. Health plan clinicians directly involved in delivering preventive services were invited to participate in the study. Final sample included 163 clinicians. Spearman's rho correlation coefficients were determined to examine the relationships between clinician's knowledge and clinician's use of CPS guidelines. Differences between knowledge and use of CPS before and after HPCG were examined by t tests. No difference was found in the familiarity with U.S. Preventive Services Task Force guidelines before and after receipt of HPCG. However, clinician's use increased significantly. A consistent set of CPS guidelines provided by competing health plans can improve the delivery of CPS among contracted health plan clinicians. This approach provides a template for competing health plans nationwide to come to consensus on guidelines that support clinicians in the delivery of CPS ().

Satellite provided customer premise services: A forecast of potential domestic demand through the year 2000. Volume 3: Appendices

NASA Technical Reports Server (NTRS)

Kratochvil, D.; Bowyer, J.; Bhushan, C.; Steinnagel, K.; Kaushal, D.; Al-Kinani, G.

1983-01-01

Voice applications, data applications, video applications, impacted baseline forecasts, market distribution, potential CPS (customers premises services) user classes, net long haul forecasts, CPS cost analysis, overall satellite forecast, CPS satellite market, Ka-band CPS satellite forecast, nationwide traffic distribution model, and intra-urban topology are discussed.

Satellite provided customer premise services: A forecast of potential domestic demand through the year 2000. Volume 3: Appendices

NASA Astrophysics Data System (ADS)

Kratochvil, D.; Bowyer, J.; Bhushan, C.; Steinnagel, K.; Kaushal, D.; Al-Kinani, G.

1983-08-01

Voice applications, data applications, video applications, impacted baseline forecasts, market distribution, potential CPS (customers premises services) user classes, net long haul forecasts, CPS cost analysis, overall satellite forecast, CPS satellite market, Ka-band CPS satellite forecast, nationwide traffic distribution model, and intra-urban topology are discussed.

Advances in lithium-sulfur batteries based on multifunctional cathodes and electrolytes

NASA Astrophysics Data System (ADS)

Pang, Quan; Liang, Xiao; Kwok, Chun Yuen; Nazar, Linda F.

2016-09-01

Amid burgeoning environmental concerns, electrochemical energy storage has rapidly gained momentum. Among the contenders in the ‘beyond lithium’ energy storage arena, the lithium-sulfur (Li-S) battery has emerged as particularly promising, owing to its potential to reversibly store considerable electrical energy at low cost. Whether or not Li-S energy storage will be able to fulfil this potential depends on simultaneously solving many aspects of its underlying conversion chemistry. Here, we review recent developments in tackling the dissolution of polysulfides — a fundamental problem in Li-S batteries — focusing on both experimental and computational approaches to tailor the chemical interactions between the sulfur host materials and polysulfides. We also discuss smart cathode architectures enabled by recent materials engineering, especially for high areal sulfur loading, as well as innovative electrolyte design to control the solubility of polysulfides. Key factors that allow long-life and high-loading Li-S batteries are summarized.

In Situ NMR Observation of the Temporal Speciation of Lithium Sulfur Batteries during Electrochemical Cycling

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

Wang, Hao; Sa, Niya; He, Meinan

The understanding of the reaction mechanism and temporal speciation of the lithium sulfur batteries is challenged by complex polysulfide disproportionation chemistry coupled with the precipitation and dissolution of species. In this report, for the first time, we present a comprehensive method to investigate lithium sulfur electrochemistry using in situ 7Li NMR spectroscopy, a technique that is capable of quantitatively capturing the evolution of the soluble and precipitated lithium (poly)sulfides during electrochemical cycling. Furthermore, through deconvolution and quantification, every lithium-bearing species was closely tracked and four-step soluble lithium polysulfide-mediated lithium sulfur electrochemistry was demonstrated in never before seen detail. Significant irreversiblemore » accumulation of Li 2S is observed on the Li metal anode after four cycles because of sulfur shuttling. We present the application of the method in order to study electrolyte/additive development and lithium protection research can be readily envisaged.« less

In Situ NMR Observation of the Temporal Speciation of Lithium Sulfur Batteries during Electrochemical Cycling

DOE PAGES

Wang, Hao; Sa, Niya; He, Meinan; ...

2017-03-03

The understanding of the reaction mechanism and temporal speciation of the lithium sulfur batteries is challenged by complex polysulfide disproportionation chemistry coupled with the precipitation and dissolution of species. In this report, for the first time, we present a comprehensive method to investigate lithium sulfur electrochemistry using in situ 7Li NMR spectroscopy, a technique that is capable of quantitatively capturing the evolution of the soluble and precipitated lithium (poly)sulfides during electrochemical cycling. Furthermore, through deconvolution and quantification, every lithium-bearing species was closely tracked and four-step soluble lithium polysulfide-mediated lithium sulfur electrochemistry was demonstrated in never before seen detail. Significant irreversiblemore » accumulation of Li 2S is observed on the Li metal anode after four cycles because of sulfur shuttling. We present the application of the method in order to study electrolyte/additive development and lithium protection research can be readily envisaged.« less

A Novel Graphene-Polysulfide Anode Material for High-Performance Lithium-Ion Batteries

PubMed Central

Ai, Wei; Xie, Linghai; Du, Zhuzhu; Zeng, Zhiyuan; Liu, Juqing; Zhang, Hua; Huang, Yunhui; Huang, Wei; Yu, Ting

2013-01-01

We report a simple and efficient approach for fabrication of novel graphene-polysulfide (GPS) anode materials, which consists of conducting graphene network and homogeneously distributed polysulfide in between and chemically bonded with graphene sheets. Such unique architecture not only possesses fast electron transport channels, shortens the Li-ion diffusion length but also provides very efficient Li-ion reservoirs. As a consequence, the GPS materials exhibit an ultrahigh reversible capacity, excellent rate capability and superior long-term cycling performance in terms of 1600, 550, 380 mAh g−1 after 500, 1300, 1900 cycles with a rate of 1, 5 and 10 A g−1 respectively. This novel and simple strategy is believed to work broadly for other carbon-based materials. Additionally, the competitive cost and low environment impact may promise such materials and technique a promising future for the development of high-performance energy storage devices for diverse applications. PMID:23903017

Intersections of Family Homelessness, CPS Involvement, and Race in Alameda County, California

PubMed Central

Shinn, Marybeth

2016-01-01

The homelessness and child protective services (CPS) systems are closely linked. This study examines the patterns and sequence of families’ involvement with homeless shelters and CPS, as well as whether involvement in each system predicts involvement in the other using linked administrative records for 258 families recruited in emergency shelters in Alameda County, California. More than half of families were reported to CPS at some point, but less than one fifth ever had a report substantiated. Reports that were uninvestigated or unfounded increased in the months leading up to shelter entry and spiked immediately afterward, but substantiations and child removals increased only later. Shelter use before study entry was associated with CPS referrals and investigations after study entry, although not with substantiated cases or child removals. However, CPS involvement before study entry was not associated with returns to shelter after study entry. These results imply that an unsubstantiated report of neglect or abuse may serve as an early warning signal for homelessness and that preventive strategies aiming to affect both homeless and child protective systems should focus on reducing homelessness. CPS workers should evaluate families’ housing needs and attempt to link families to appropriate resources. Black families were disproportionately referred to CPS after shelter entry after controlling for other family characteristics, but race was not associated with substantiations of neglect or abuse or with child removals. Findings lend modest support to human decision-making and institutional explanations of racial disproportionalities in CPS involvement, especially for reporters outside of the CPS system. PMID:27318034

The integration of information and communication technology into community pharmacists practice in Barcelona.

PubMed

Lupiáñez-Villanueva, Francisco; Hardey, Michael; Lluch, Maria

2014-03-01

The study aims to identify community pharmacists' (CPs) utilization of information and communication technology (ICT); to develop and characterize a typology of CPs' utilization of ICT and to identify factors that can enhance or inhibit the use of these technologies. An online survey of the 7649 members of the Pharmacist Association of Barcelona who had a registered email account in 2006 was carried out. Factor analysis, cluster analysis and binomial logit modelling were undertaken. Multivariate analysis of the CPs' responses to the survey (648) revealed two profiles of adoption of ICT. The first profile (40.75%) represents those CPs who place high emphasis on ICT within their practice. This group is therefore referred to as 'integrated CPs'. The second profile (59.25%) represents those CPs who make less use of ICT and so are consequently labelled 'non-integrated CPs'. Statistical modelling was used to identify variables that were important in predisposing CPs to integrate ICT with their work. From the analysis it is evident that responses to questions relating to 'recommend patients going on line for health information'; 'patients discuss or share their Internet health information findings'; 'emphasis on the Internet for communication and dissemination' and 'Pharmacists Professional Association information' play a positive and significant role in the probability of being an 'integrated CP'. The integration of ICT within CPs' practices cannot be adequately understood and appreciated without examining how CPs are making use of ICT within their own practice, their organizational context and the nature of the pharmacists-client relationship.

Pediatricians’ Self-Reported Knowledge, Attitudes, and Practices about Child Passenger Safety

PubMed Central

Zonfrillo, Mark R.; Sauber-Schatz, Erin K.; Hoffman, Benjamin D.; Durbin, Dennis R.

2014-01-01

Objective To evaluate pediatricians’ self-reported knowledge, attitudes, and dissemination practices regarding the new American Academy of Pediatrics’ (AAP) child passenger safety (CPS) policy recommendations. Study design A cross-sectional survey was distributed to pediatric primary care physicians via AAP e-mail distribution lists. Knowledge, attitudes, and practices related to current AAP CPS recommendations and the revised policy statement were ascertained. Results There were 718 respondents from 3497 physicians with active e-mail addresses, resulting in a 20.5% response rate, of which 533 were eligible based on the initial survey question. All 6 CPS knowledge and scenario-based items were answered correctly by 52.9% of the sample; these respondents were identified as the “high knowledge” group. Pediatricians with high knowledge were more likely to be female (P < .001), to have completed a pediatrics residency (vs medicine-pediatrics) (P = .03), and have a child between 4 and 7 years of age (P = .001). CPS information was distributed more frequently at routine health visits for patients 0-2 years of age vs those 4-12 years of age. Those with high knowledge were less likely to report several specific barriers to dissemination of CPS information, more likely to allot adequate time and discuss CPS with parents, and had greater confidence for topics related to all CPS topics. Conclusions Although CPS knowledge is generally high among respondents, gaps in knowledge still exist. Knowledge is associated with attitudes, practices, barriers, and facilitators of CPS guideline dissemination. These results identify opportunities to increase knowledge and implement strategies to routinely disseminate CPS information in the primary care setting. PMID:25195160

Altered cerebral protein synthesis in fragile X syndrome: studies in human subjects and knockout mice

PubMed Central

Qin, Mei; Schmidt, Kathleen C; Zametkin, Alan J; Bishu, Shrinivas; Horowitz, Lisa M; Burlin, Thomas V; Xia, Zengyan; Huang, Tianjiang; Quezado, Zenaide M; Smith, Carolyn Beebe

2013-01-01

Dysregulated protein synthesis is thought to be a core phenotype of fragile X syndrome (FXS). In a mouse model (Fmr1 knockout (KO)) of FXS, rates of cerebral protein synthesis (rCPS) are increased in selective brain regions. We hypothesized that rCPS are also increased in FXS subjects. We measured rCPS with the ℒ-[1-11C]leucine positron emission tomography (PET) method in whole brain and 10 regions in 15 FXS subjects who, because of their impairments, were studied under deep sedation with propofol. We compared results with those of 12 age-matched controls studied both awake and sedated. In controls, we found no differences in rCPS between awake and propofol sedation. Contrary to our hypothesis, FXS subjects under propofol sedation had reduced rCPS in whole brain, cerebellum, and cortex compared with sedated controls. To investigate whether propofol could have a disparate effect in FXS subjects masking usually elevated rCPS, we measured rCPS in C57Bl/6 wild-type (WT) and KO mice awake or under propofol sedation. Propofol decreased rCPS substantially in most regions examined in KO mice, but in WT mice caused few discrete changes. Propofol acts by decreasing neuronal activity either directly or by increasing inhibitory synaptic activity. Our results suggest that changes in synaptic signaling can correct increased rCPS in FXS. PMID:23299245

Neurophysiological Correlates of Musical and Prosodic Phrasing: Shared Processing Mechanisms and Effects of Musical Expertise

PubMed Central

Steinhauer, Karsten; DePriest, John; Koelsch, Stefan

2016-01-01

The processing of prosodic phrase boundaries in language is immediately reflected by a specific event-related potential component called the Closure Positive Shift (CPS). A component somewhat reminiscent of the CPS in language has also been reported for musical phrases (i.e., the so-called ‘music CPS’). However, in previous studies the quantification of the music-CPS as well as its morphology and timing differed substantially from the characteristics of the language-CPS. Therefore, the degree of correspondence between cognitive mechanisms of phrasing in music and in language has remained questionable. Here, we probed the shared nature of mechanisms underlying musical and prosodic phrasing by (1) investigating whether the music-CPS is present at phrase boundary positions where the language-CPS has been originally reported (i.e., at the onset of the pause between phrases), and (2) comparing the CPS in music and in language in non-musicians and professional musicians. For the first time, we report a positive shift at the onset of musical phrase boundaries that strongly resembles the language-CPS and argue that the post-boundary ‘music-CPS’ of previous studies may be an entirely distinct ERP component. Moreover, the language-CPS in musicians was found to be less prominent than in non-musicians, suggesting more efficient processing of prosodic phrases in language as a result of higher musical expertise. PMID:27192560

77 FR 43122 - Corob North America, a Subsidiary of CPS Color Equipment, Inc., Including On-Site Leased Workes...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-23

... Subsidiary of CPS Color Equipment, Inc., Including On-Site Leased Workes From Pionear and Integra Staffing..., 2012, applicable to workers of CPS Color Equipment, Inc., formerly known as Corob North America... under the name CPS Color Equipment, Inc. The amended notice applicable to TA-W-81,222 is hereby issued...

Inhibitory effect of dietary capsaicin on liver fibrosis in mice.

PubMed

Bitencourt, Shanna; Stradiot, Leslie; Verhulst, Stefaan; Thoen, Lien; Mannaerts, Inge; van Grunsven, Leo A

2015-06-01

Virtually all chronic liver injuries result in the activation of hepatic stellate cells (HSCs). In their activated state, these cells are the main collagen-producing cells implicated in liver fibrosis. Capsaicin (CPS), the active compound of chili peppers, can modulate the activation and migration of HSCs in vitro. Here, we evaluated the potential protective and prophylactic effects of CPS related to cholestatic and hepatotoxic-induced liver fibrosis and its possible underlying mechanism of action. Male Balb/c mice received dietary CPS after 3 days of bile duct ligation (BDL) or before and during carbon tetrachloride (CCl4 ) injections. Mice receiving dietary CPS after BDL had a significant improvement of liver fibrosis accompanied by a decrease in collagen deposition and downregulation of activation markers in isolated HSCs. In the CCl4 model, dietary CPS inhibited the upregulation of profibrogenic markers. However, CPS could not attenuate the CCl4 -induced fibrosis when it was already established. Furthermore, in vitro CPS treatment inhibited the autophagic process during HSC activation. Dietary CPS has potential benefits in the therapy of cholestatic liver fibrosis and in the prophylaxis of hepatotoxic-induced liver injury. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Engagement and action for health: the contribution of leaders' collaborative skills to partnership success.

PubMed

El Ansari, Walid; Oskrochi, Reza; Phillips, Ceri

2009-01-01

A multi-site evaluation (survey) of five Kellogg-funded Community Partnerships (CPs) in South Africa was undertaken to explore the relationship between leadership skills and a range of 30 operational, functional and organisational factors deemed critical to successful CPs. The CPs were collaborative academic-health service-community efforts aimed at health professions education reforms. The level of agreement to eleven dichotomous ('Yes/No') leadership skills items was used to compute two measures of members' appreciation of their CPs' leadership. The associations between these measures and 30 CPs factors were explored, and the partnership factors that leadership skills explained were assessed after controlling. Respondents who perceived the leadership of their CPs favourably had more positive ratings across 30 other partnership factors than those who rated leadership skills less favourably, and were more likely to report a positive cost/ benefit ratio. In addition, respondents who viewed their CPs' leadership positively also rated the operational understanding, the communication mechanisms, as well as the rules and procedures of the CPs more favourably. Leadership skills explained between 20% and 7% of the variance of 10 partnership factors. The influence of leaders' skills in effective health-focussed partnerships is much broader than previously conceptualised.

Silicon deposition in nanopores using a liquid precursor.

PubMed

Masuda, Takashi; Tatsuda, Narihito; Yano, Kazuhisa; Shimoda, Tatsuya

2016-11-22

Techniques for depositing silicon into nanosized spaces are vital for the further scaling down of next-generation devices in the semiconductor industry. In this study, we filled silicon into 3.5-nm-diameter nanopores with an aspect ratio of 70 by exploiting thermodynamic behaviour based on the van der Waals energy of vaporized cyclopentasilane (CPS). We originally synthesized CPS as a liquid precursor for semiconducting silicon. Here we used CPS as a gas source in thermal chemical vapour deposition under atmospheric pressure because vaporized CPS can fill nanopores spontaneously. Our estimation of the free energy of CPS based on Lifshitz van der Waals theory clarified the filling mechanism, where CPS vapour in the nanopores readily undergoes capillary condensation because of its large molar volume compared to those of other vapours such as water, toluene, silane, and disilane. Consequently, a liquid-specific feature was observed during the deposition process; specifically, condensed CPS penetrated into the nanopores spontaneously via capillary force. The CPS that filled the nanopores was then transformed into solid silicon by thermal decomposition at 400 °C. The developed method is expected to be used as a nanoscale silicon filling technology, which is critical for the fabrication of future quantum scale silicon devices.

Silicon deposition in nanopores using a liquid precursor

NASA Astrophysics Data System (ADS)

Masuda, Takashi; Tatsuda, Narihito; Yano, Kazuhisa; Shimoda, Tatsuya

2016-11-01

Techniques for depositing silicon into nanosized spaces are vital for the further scaling down of next-generation devices in the semiconductor industry. In this study, we filled silicon into 3.5-nm-diameter nanopores with an aspect ratio of 70 by exploiting thermodynamic behaviour based on the van der Waals energy of vaporized cyclopentasilane (CPS). We originally synthesized CPS as a liquid precursor for semiconducting silicon. Here we used CPS as a gas source in thermal chemical vapour deposition under atmospheric pressure because vaporized CPS can fill nanopores spontaneously. Our estimation of the free energy of CPS based on Lifshitz van der Waals theory clarified the filling mechanism, where CPS vapour in the nanopores readily undergoes capillary condensation because of its large molar volume compared to those of other vapours such as water, toluene, silane, and disilane. Consequently, a liquid-specific feature was observed during the deposition process; specifically, condensed CPS penetrated into the nanopores spontaneously via capillary force. The CPS that filled the nanopores was then transformed into solid silicon by thermal decomposition at 400 °C. The developed method is expected to be used as a nanoscale silicon filling technology, which is critical for the fabrication of future quantum scale silicon devices.

Prevalence and quality of clinical pathways in Swedish intensive care units: a national survey.

PubMed

Bjurling-Sjöberg, Petronella; Jansson, Inger; Wadensten, Barbro; Engström, Gabriella; Pöder, Ulrika

2014-02-01

To identify the prevalence of clinical pathways (CPs) in Swedish intensive care units (ICUs) and to explore the quality, content and evidence base of the documents. A descriptive and explorative survey of all Swedish ICUs (N84) and a review of submitted examples of CPs (n12) were conducted. CPs were in use at 20% of the Swedish ICUs. There was a significant geographic variation but no relationship between the use of CPs and category of hospital, type of ICU, size of ICU or type of health record applied. In total, 56 CPs were reported within a range of scopes and extensions. The content of the ICUs' CPs, as well as the degree to which they were interprofessional, evidence based, and renewed varied. Progress has been made in relation to CPs in recent years, but there is potential for further improvements. None of the ICUs had CPs that contained all key characteristics of a high-quality, interprofessional and evidence-based CP identified in the literature. Greater knowledge sharing and cooperation within the field would be beneficial, and further research is needed. © 2013 John Wiley & Sons, Ltd.

Preparation and evaluation of cilnidipine microemulsion

PubMed Central

Tandel, Hemal; Raval, Krunal; Nayani, Anil; Upadhay, Manish

2012-01-01

Cilnidipine, a calcium channel blocker having neuroprotective action and BCS Class II drug, hence formulating in Microemulsion will increase solubility, absorption and bioavailability. The formulation was prepared using titration method by tocotrienol, tween 20 and transcutol HP as oil, surfactant and co-surfactant and characterized for dilutability, dye solubility, assay (98.39±0.06), pH (6.6±1.5), Viscosity (98±1.0 cps) and Conductivity (0.2±0.09 μS/cm). The formulation was optimized on basis of percentage transmittance (99.269±0.23 at 700 nm), Globule size (13.31±4.3 nm) and zeta potential (–11.4±2.3 mV). Cilnidipine microemulsion was found to be stable for 3 months. PMID:23066184

Thermal Hysteresis of MEMS Packaged Capacitive Pressure Sensor (CPS) Based 3C-SiC

NASA Astrophysics Data System (ADS)

Marsi, N.; Majlis, B. Y.; Mohd-Yasin, F.; Hamzah, A. A.; Mohd Rus, A. Z.

2016-11-01

Presented herein are the effects of thermal hysteresis analyses of the MEMS packaged capacitive pressure sensor (CPS). The MEMS CPS was employed on Si-on-3C-SiC wafer that was performed using the hot wall low-pressure chemical vapour deposition (LPCVD) reactors at the Queensland Micro and Nanotechnology Center (QMNC), Griffith University and fabricated using the bulk-micromachining process. The MEMS CPS was operated at an extreme temperature up to 500°C and high external pressure at 5.0 MPa. The thermal hysteresis phenomenon that causes the deflection, strain and stress on the 3C-SiC diaphragm spontaneously influence the MEMS CPS performances. The differences of temperature, hysteresis, and repeatability test were presented to demonstrate the functionality of the MEMS packaged CPS. As expected, the output hysteresis has a low hysteresis (less than 0.05%) which has the hardness greater than the traditional silicon. By utilizing this low hysteresis, it was revealed that the MEMS packaged CPS has high repeatability and stability of the sensor.

Highly Efficient Iodine Capture by Layered Double Hydroxides Intercalated with Polysulfides

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

Ma, Shulan; Islam, Saiful M.; Shim, Yurina

2014-12-23

We demonstrate strong iodine (I-2) vapor adsorption using Mg/Al layered double hydroxide (MgAl-LDH) nanocomposites intercalated with polysulfide (S-x(2-)) groups (S-x-LDH, x = 2, 4, 6). The as-prepared LDH/polysulfide hybrid materials display highly efficient iodine capture resulting from the reducing property of the intercalated polysulfides. During adsorption, the I-2 molecules are reduced to I-3(-) anions by the intercalated [S-x](2-) groups that simultaneously are oxidized to form S8. In addition to the chemical adsorption, additional molecular I-2 is physically captured by the LDH composites. As a result of these parallel processes, and despite their very low BET surface areas, the iodine capturemore » capacities of S-2-LDH, S-4-LDH, and S-6-LDH are similar to 1.32, 1.52, and 1.43 g/g, respectively, with a maximum adsorption of 152% (wt %). Thermogravimetric and differential thermal analysis (TG-DTA), energy dispersive X-ray spectroscopy (EDS), and temperature-variable powder X-ray diffraction (XRD) measurements show the resulting I-3(-) ions that intercalated into the LDH gallery have high thermal stability (>= 350 degrees C). The excellent iodine adsorption performance combined with the facile preparation points to the S-x-LDH systems as potential superior materials for adsorption of radioactive iodine, a waste product of the nuclear power industry.« less

Boron- and nitrogen-doped reduced graphene oxide coated separators for high-performance Li-S batteries

NASA Astrophysics Data System (ADS)

Han, Pauline; Manthiram, Arumugam

2017-11-01

Lithium-sulfur (Li-S) batteries are regarded as a potential next-generation energy storage system but they are hampered by low active-material utilization, polysulfide shuttling, and rapid capacity fade. We present here the use of lightweight boron- and nitrogen-doped reduced graphene oxide (B-rGO, N-rGO) coated separators to suppress polysulfide diffusion and enhance active material utilization at high sulfur contents. B-rGO and N-rGO are synthesized through a facile modified Hummer's method involving the exfoliation of graphite sheets. Upon reduction, the carbon forms valuable interlayers with dynamic spacings for polysulfide trapping. Freeze-drying is utilized to preserve the structure of the pillow-like carbon, which is then slurry-coated onto a separator and placed against a sulfur cathode. The advantages of boron and nitrogen and their affinity towards polysulfides is compared while noting the lighter carbon coatings with good electrochemical stability. The cells attain a loading of 4.0 mg cm-2 with a high sulfur content of 66.5 ± 0.5 wt % on including the weight of the coatings. After a long cycle life of 400 cycles, N-rGO and B-rGO are still able to maintain a specific capacity of, respectively, 430 mA h g-1 and 367 mA h g-1.

Three-Dimensionally Hierarchical Ni/Ni3S2/S Cathode for Lithium-Sulfur Battery.

PubMed

Li, Zhe; Zhang, Shiguo; Zhang, Jiaheng; Xu, Miao; Tatara, Ryoichi; Dokko, Kaoru; Watanabe, Masayoshi

2017-11-08

Lithium-sulfur (Li-S) batteries have attracted interest as a promising energy-storage technology due to their overwhelming advantages such as high energy density and low cost. However, their commercial success is impeded by deterioration of sulfur utilization, significant capacity fade, and poor cycle life, which are principally originated from the severe shuttle effect in relation to the dissolution and migration of lithium polysulfides. Herein, we proposed an effective and facile strategy to anchor the polysulfides and improve sulfur loading by constructing a three-dimensionally hierarchical Ni/Ni 3 S 2 /S cathode. This self-supported hybrid architecture is sequentially fabricated by the partial sulfurization of Ni foam by a mild hydrothermal process, followed by physical loading of elemental sulfur. The incorporation of Ni 3 S 2 , with high electronic conductivity and strong polysulfide adsorption capability, can not only empower the cathode to alleviate the shuttle effect, but also afford a favorable electrochemical environment with lower interfacial resistance, which could facilitate the redox kinetics of the anchored polysulfides. Consequently, the obtained Ni/Ni 3 S 2 /S cathode with a sulfur loading of ∼4.0 mg/cm 2 demonstrated excellent electrochemical characteristics. For example, at high current density of 4 mA/cm 2 , this thick cathode demonstrated a discharge capacity of 441 mAh/g at the 150th cycle.

Carbon felt interlayer derived from rice paper and its synergistic encapsulation of polysulfides for lithium-sulfur batteries

NASA Astrophysics Data System (ADS)

Yang, Kai; Zhong, Lei; Guan, Ruiteng; Xiao, Min; Han, Dongmei; Wang, Shuanjin; Meng, Yuezhong

2018-05-01

Lithium-sulfur (Li-S) batteries have remarkably high theoretical specific capacity as promising candidates for next-generation energy storage. However, the "polysulfides shuttle" effect hampers its commercial application. Here, we use a kind of rice paper as a raw material to get inorganic oxides doping carbon felt by the facile carbonization method, and then modified by a simple coating process using poly (fluorenyl ether ketone) and Super P slurry. The special structure of the carbon felt derived from rice paper and its modified layer endow the final electronic conductive interlayer with inherent polysulfides absorbents and ion Coulombic repulsion functions, respectively, which show synergistic effect for trapping polysulfides. As an interlayer of Li-S batteries, the obtained carbon felt/poly (fluorenyl ether ketone)& Super P (CFSS) interlayer shows excellent electrochemical performance in improving specific capacity and decreasing polarization. The batteries with CFSS interlayer exhibit a high capacity of 837 mA h g-1 at 2.0 C and a high initial capacity of 1073.4 mA h g-1 and good capacity retention of 824.5 mA h g-1 after 500 cycles at 0.5 C. CFSS interlayer also shows excellent anti-self-discharge performance. Therefore, the simple and economical CFSS interlayer can be considered as a promising component for high performance Li-S batteries.

Solvent effects on polysulfide redox kinetics and ionic conductivity in lithium-sulfur batteries

DOE PAGES

Fan, Frank Y.; Pan, Menghsuan Sam; Lau, Kah Chun; ...

2016-11-25

Lithium-sulfur (Li-S) batteries have high theoretical energy density and low raw materials cost compared to present lithium-ion batteries and are thus promising for use in electric transportation and other applications. A major obstacle for Li-S batteries is low rate capability, especially at the low electrolyte/sulfur (E/S) ratios required for high energy density. Herein, we investigate several potentially rate-limiting factors for Li-S batteries. We study the ionic conductivity of lithium polysulfide solutions of varying concentration and in different ether-based solvents and their exchange current density on glassy carbon working electrodes. We believe this is the first such investigation of exchange currentmore » density for lithium polysulfide in solution. Exchange current densities are measured using both electrochemical impedance spectroscopy and steady-state galvanostatic polarization. In the range of interest (1-8 M [S]), the ionic conductivity monotonically decreases with increasing sulfur concentration while exchange current density shows a more complicated relationship to sulfur concentration. The electrolyte solvent dramatically affects ionic conductivity and exchange current density. Finally, the measured ionic conductivities and exchange current densities are also used to interpret the overpotential and rate capability of polysulfide-nanocarbon suspensions; this analysis demonstrates that ionic conductivity is the rate-limiting property in the solution regime (i.e. between Li 2S 8 and Li 2S 4).« less

Porous-Shell Vanadium Nitride Nanobubbles with Ultrahigh Areal Sulfur Loading for High-Capacity and Long-Life Lithium-Sulfur Batteries.

PubMed

Ma, Lianbo; Yuan, Hao; Zhang, Wenjun; Zhu, Guoyin; Wang, Yanrong; Hu, Yi; Zhao, Peiyang; Chen, Renpeng; Chen, Tao; Liu, Jie; Hu, Zheng; Jin, Zhong

2017-12-13

Lithium-sulfur (Li-S) batteries hold great promise for the applications of high energy density storage. However, the performances of Li-S batteries are restricted by the low electrical conductivity of sulfur and shuttle effect of intermediate polysulfides. Moreover, the areal loading weights of sulfur in previous studies are usually low (around 1-3 mg cm -2 ) and thus cannot fulfill the requirement for practical deployment. Herein, we report that porous-shell vanadium nitride nanobubbles (VN-NBs) can serve as an efficient sulfur host in Li-S batteries, exhibiting remarkable electrochemical performances even with ultrahigh areal sulfur loading weights (5.4-6.8 mg cm -2 ). The large inner space of VN-NBs can afford a high sulfur content and accommodate the volume expansion, and the high electrical conductivity of VN-NBs ensures the effective utilization and fast redox kinetics of polysulfides. Moreover, VN-NBs present strong chemical affinity/adsorption with polysulfides and thus can efficiently suppress the shuttle effect via both capillary confinement and chemical binding, and promote the fast conversion of polysulfides. Benefiting from the above merits, the Li-S batteries based on sulfur-filled VN-NBs cathodes with 5.4 mg cm -2 sulfur exhibit impressively high areal/specific capacity (5.81 mAh cm -2 ), superior rate capability (632 mAh g -1 at 5.0 C), and long cycling stability.

Polysulfide-Blocking Microporous Polymer Membrane Tailored for Hybrid Li-Sulfur Flow Batteries.

PubMed

Li, Changyi; Ward, Ashleigh L; Doris, Sean E; Pascal, Tod A; Prendergast, David; Helms, Brett A

2015-09-09

Redox flow batteries (RFBs) present unique opportunities for multi-hour electrochemical energy storage (EES) at low cost. Too often, the barrier for implementing them in large-scale EES is the unfettered migration of redox active species across the membrane, which shortens battery life and reduces Coulombic efficiency. To advance RFBs for reliable EES, a new paradigm for controlling membrane transport selectivity is needed. We show here that size- and ion-selective transport can be achieved using membranes fabricated from polymers of intrinsic microporosity (PIMs). As a proof-of-concept demonstration, a first-generation PIM membrane dramatically reduced polysulfide crossover (and shuttling at the anode) in lithium-sulfur batteries, even when sulfur cathodes were prepared as flowable energy-dense fluids. The design of our membrane platform was informed by molecular dynamics simulations of the solvated structures of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) vs lithiated polysulfides (Li2Sx, where x = 8, 6, and 4) in glyme-based electrolytes of different oligomer length. These simulations suggested polymer films with pore dimensions less than 1.2-1.7 nm might incur the desired ion-selectivity. Indeed, the polysulfide blocking ability of the PIM-1 membrane (∼0.8 nm pores) was improved 500-fold over mesoporous Celgard separators (∼17 nm pores). As a result, significantly improved battery performance was demonstrated, even in the absence of LiNO3 anode-protecting additives.

Characterization and analysis of the cotton cyclopropane fatty acid synthase family and their contribution to cyclopropane fatty acid synthesis

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

Yu X. H.; Shanklin J.; Rawat, R.

Cyclopropane fatty acids (CPA) have been found in certain gymnosperms, Malvales, Litchi and other Sapindales. The presence of their unique strained ring structures confers physical and chemical properties characteristic of unsaturated fatty acids with the oxidative stability displayed by saturated fatty acids making them of considerable industrial interest. While cyclopropenoid fatty acids (CPE) are well-known inhibitors of fatty acid desaturation in animals, CPE can also inhibit the stearoyl-CoA desaturase and interfere with the maturation and reproduction of some insect species suggesting that in addition to their traditional role as storage lipids, CPE can contribute to the protection of plants frommore » herbivory. Three genes encoding cyclopropane synthase homologues GhCPS1, GhCPS2 and GhCPS3 were identified in cotton. Determination of gene transcript abundance revealed differences among the expression of GhCPS1, 2 and 3 showing high, intermediate and low levels, respectively, of transcripts in roots and stems; whereas GhCPS1 and 2 are both expressed at low levels in seeds. Analyses of fatty acid composition in different tissues indicate that the expression patterns of GhCPS1 and 2 correlate with cyclic fatty acid (CFA) distribution. Deletion of the N-terminal oxidase domain lowered GhCPS's ability to produce cyclopropane fatty acid by approximately 70%. GhCPS1 and 2, but not 3 resulted in the production of cyclopropane fatty acids upon heterologous expression in yeast, tobacco BY2 cell and Arabidopsis seed. In cotton GhCPS1 and 2 gene expression correlates with the total CFA content in roots, stems and seeds. That GhCPS1 and 2 are expressed at a similar level in seed suggests both of them can be considered potential targets for gene silencing to reduce undesirable seed CPE accumulation. Because GhCPS1 is more active in yeast than the published Sterculia CPS and shows similar activity when expressed in model plant systems, it represents a strong candidate gene for CFA accumulation via heterologous expression in production plants.« less

Molecular mapping of the cell wall polysaccharides of the human pathogen Streptococcus agalactiae

NASA Astrophysics Data System (ADS)

Beaussart, Audrey; Péchoux, Christine; Trieu-Cuot, Patrick; Hols, Pascal; Mistou, Michel-Yves; Dufrêne, Yves F.

2014-11-01

The surface of many bacterial pathogens is covered with polysaccharides that play important roles in mediating pathogen-host interactions. In Streptococcus agalactiae, the capsular polysaccharide (CPS) is recognized as a major virulence factor while the group B carbohydrate (GBC) is crucial for peptidoglycan biosynthesis and cell division. Despite the important roles of CPS and GBC, there is little information available on the molecular organization of these glycopolymers on the cell surface. Here, we use atomic force microscopy (AFM) and transmission electron microscopy (TEM) to analyze the nanoscale distribution of CPS and GBC in wild-type (WT) and mutant strains of S. agalactiae. TEM analyses reveal that in WT bacteria, peptidoglycan is covered with a very thin (few nm) layer of GBC (the ``pellicle'') overlaid by a 15-45 nm thick layer of CPS (the ``capsule''). AFM-based single-molecule mapping with specific antibody probes shows that CPS is exposed on WT cells, while it is hardly detected on mutant cells impaired in CPS production (ΔcpsE mutant). By contrast, both TEM and AFM show that CPS is over-expressed in mutant cells altered in GBC expression (ΔgbcO mutant), indicating that the production of the two surface glycopolymers is coordinated in WT cells. In addition, AFM topographic imaging and molecular mapping with specific lectin probes demonstrate that removal of CPS (ΔcpsE), but not of GBC (ΔgbcO), leads to the exposure of peptidoglycan, organized into 25 nm wide bands running parallel to the septum. These results indicate that CPS forms a homogeneous barrier protecting the underlying peptidoglycan from environmental exposure, while the presence of GBC does not prevent peptidoglycan detection. This work shows that single-molecule AFM, combined with high-resolution TEM, represents a powerful platform for analysing the molecular arrangement of the cell wall polymers of bacterial pathogens.

Capsular Sialyltransferase Specificity Mediates Different Phenotypes in Streptococcus suis and Group B Streptococcus

PubMed Central

Roy, David; Takamatsu, Daisuke; Okura, Masatoshi; Goyette-Desjardins, Guillaume; Van Calsteren, Marie-Rose; Dumesnil, Audrey; Gottschalk, Marcelo; Segura, Mariela

2018-01-01

The capsular polysaccharide (CPS) represents a key virulence factor for most encapsulated streptococci. Streptococcus suis and Group B Streptococcus (GBS) are both well-encapsulated pathogens of clinical importance in veterinary and/or human medicine and responsible for invasive systemic diseases. S. suis and GBS are the only Gram-positive bacteria which express a sialylated CPS at their surface. An important difference between these two sialylated CPSs is the linkage between the side-chain terminal galactose and sialic acid, being α-2,6 for S. suis but α-2,3 for GBS. It is still unclear how sialic acid may affect CPS production and, consequently, the pathogenesis of the disease caused by these two bacterial pathogens. Here, we investigated the role of sialic acid and the putative effect of sialic acid linkage modification in CPS synthesis using inter-species allelic exchange mutagenesis. To this aim, a new molecular biogenetic approach to express CPS with modified sialic acid linkage was developed. We showed that sialic acid (and its α-2,6 linkage) is crucial for S. suis CPS synthesis, whereas for GBS, CPS synthesis may occur in presence of an α-2,6 sialyltransferase or in absence of sialic acid moiety. To evaluate the effect of the CPS composition/structure on sialyltransferase activity, two distinct capsular serotypes within each bacterial species were compared (S. suis serotypes 2 and 14 and GBS serotypes III and V). It was demonstrated that the observed differences in sialyltransferase activity and specificity between S. suis and GBS were serotype unrestricted. This is the first time that a study investigates the interspecies exchange of capsular sialyltransferase genes in Gram-positive bacteria. The obtained mutants represent novel tools that could be used to further investigate the immunomodulatory properties of sialylated CPSs. Finally, in spite of common CPS structural characteristics and similarities in the cps loci, sialic acid exerts differential control of CPS expression by S. suis and GBS. PMID:29666608

Oncologic emergencies in a cancer center emergency department and in general emergency departments countywide and nationwide.

PubMed

Yang, Zhi; Yang, Runxiang; Kwak, Min Ji; Qdaisat, Aiham; Lin, Junzhong; Begley, Charles E; Reyes-Gibby, Cielito C; Yeung, Sai-Ching Jim

2018-01-01

Although cancer patients (CPs) are increasingly likely to visit emergency department (ED), no population-based study has compared the characteristics of CPs and non-cancer patients (NCPs) who visit the ED and examined factors associated with hospitalization via the ED. In this study, we (1) compared characteristics and diagnoses between CPs and NCPs who visited the ED in a cancer center or general hospital; (2) compared characteristics and diagnoses between CPs and NCPs who were hospitalized via the ED in a cancer center or general hospital; and (3) investigated important factors associated with such hospitalization. We analyzed patient characteristic and diagnosis [based on International Classification of Diseases-9 (ICD-9) codes] data from the ED of a comprehensive cancer center (MDACC), 24 general EDs in Harris County, Texas (HCED), and the National Hospital Ambulatory Medical Care Survey (NHAMCS) from 1/1/2007-12/31/2009. Approximately 3.4 million ED visits were analyzed: 47,245, 3,248,973, and 104,566 visits for MDACC, HCED, and NHAMCS, respectively, of which 44,143 (93.4%), 44,583 (1.4%), and 632 (0.6%) were CP visits. CPs were older than NCPs and stayed longer in EDs. Lung, gastrointestinal (excluding colorectal), and genitourinary (excluding prostate) cancers were the three most common diagnoses related to ED visits at general EDs. CPs visiting MDACC were more likely than CPs visiting HCED to be privately insured. CPs were more likely than NCPs to be hospitalized. Pneumonia and influenza, fluid and electrolyte disorders, and fever were important predictive factors for CP hospitalization; coronary artery disease, cerebrovascular disease, and heart failure were important factors for NCP hospitalization. CPs consumed more ED resources than NCPs and had a higher hospitalization rate. Given the differences in characteristics and diagnoses between CPs and NCPs, ED physicians must pay special attention to CPs and be familiar with their unique set of oncologic emergencies.

Welfare recipients’ involvement with child protective services after welfare reform

PubMed Central

Nam, Yunju; Meezan, William; Danziger, Sandra K.

2007-01-01

Objective This study identifies factors associated with child protective services (CPS) involvement among current and former welfare recipients after welfare reform legislation was passed in the US in 1996. Method Data come from the Women’s Employment Study, a longitudinal study of randomly selected welfare recipients living in a Michigan city in 1997 (N = 541). In order to identify risk factors for CPS involvement among current and former welfare recipients, multinomial logit analyses with 29 independent variables were employed on a trichotomous dependent variable: no CPS involvement, investigation only, and supervision by CPS after investigation. Results The relationship between work and involvement with CPS differs by work experience prior to welfare reform. As the percentage of months working after welfare reform increased, the risk of being investigated by CPS declined among those with prior work experience but the risk increased among those without prior work experience. However, work variables were not significant predictors of supervision by CPS after an initial investigation. Further, race, cohabitation, childhood welfare receipt, having a learning disability, having a large number of children, being newly divorced, living in a high problem neighborhood, and being convicted of a crime were associated with one’s probability of being either investigated or supervised by CPS. Conclusions These findings suggest that employment could have increased the stress levels of current or former welfare recipients without prior work experience to the point where they were prone to minor child rearing mistakes that resulted in a CPS investigation, but were not severe enough to warrant opening the case for supervision. Supports should be provided to welfare mothers who are prone to involvement with CPS; expansions in the childcare subsidy and a reduction or delay in work requirements might also help these families. PMID:17116329

Welfare recipients' involvement with child protective services after welfare reform.

PubMed

Nam, Yunju; Meezan, William; Danziger, Sandra K

2006-11-01

This study identifies factors associated with child protective services (CPS) involvement among current and former welfare recipients after welfare reform legislation was passed in the US in 1996. Data come from the Women's Employment Study, a longitudinal study of randomly selected welfare recipients living in a Michigan city in 1997 (N=541). In order to identify risk factors for CPS involvement among current and former welfare recipients, multinomial logit analyses with 29 independent variables were employed on a trichotomous dependent variable: no CPS involvement, investigation only, and supervision by CPS after investigation. The relationship between work and involvement with CPS differs by work experience prior to welfare reform. As the percentage of months working after welfare reform increased, the risk of being investigated by CPS declined among those with prior work experience but the risk increased among those without prior work experience. However, work variables were not significant predictors of supervision by CPS after an initial investigation. Further, race, cohabitation, childhood welfare receipt, having a learning disability, having a large number of children, being newly divorced, living in a high problem neighborhood, and being convicted of a crime were associated with one's probability of being either investigated or supervised by CPS. These findings suggest that employment could have increased the stress levels of current or former welfare recipients without prior work experience to the point where they were prone to minor child rearing mistakes that resulted in a CPS investigation, but were not severe enough to warrant opening the case for supervision. Supports should be provided to welfare mothers who are prone to involvement with CPS; expansions in the childcare subsidy and a reduction or delay in work requirements might also help these families.

Prevalence of coagulase-positive staphylococci, other than Staphylococcus aureus, in bovine mastitis.

PubMed

Roberson, J R; Fox, L K; Hancock, D D; Gay, J M; Besser, T E

1996-01-01

To determine prevalence and relevance of coagulase-positive Staphylococcus hyicus and S intermedius intramammary infections (IMI) in dairy cows and determine the ability of the 4-hour tube coagulase (TC) test to differentiate the coagulase-positive staphylococci (CPS). Prevalence of CPS was determined for primiparous cows (point prevalence and prevalence at first parturition) and multiparous cows (point prevalence) of 2 herd groups: < 6% CPS IMI prevalence = low prevalence (LP); > 10% CPS IMI prevalence = high prevalence (HP). For prevalence, cows of 22 dairy herds. For TC, 1,038 CPS strains isolated from cow milk. Speciation of CPS from aseptically collected composite milk samples was performed. Coagulase-positive isolates from 4 cow groups were tested for their ability to coagulate rabbit plasma by 4 hours: LP and HP primiparous cows at parturition, and LP and HP cows any time after first parturition. Of 487 CPS in the prevalence study, 82.1% were S aureus, 17.7% were coagulase-positive S hyicus, and 0.2% were S intermedius. Of all CPS IMI in LP herds, 34% were coagulase-positive S hyicus; of all CPS IMI in HP herds, 9% were coagulase-positive S hyicus. Coagulase-positive S hyicus appeared to persist to the end of lactation in 4 cows (mean linear somatic cell count = 3.7). The TC test was > or = 97% sensitive, < or = 33% specific, and had a predictive value positive range of 60 to 97% for S aureus isolates. Coagulase-positive S hyicus appears capable of inducing chronic, low-grade IMI. Staphylococcus intermedius does not appear to be an important mastitis pathogen. The TC test is not valid to use as the sole method to differentiate CPS species.

Preferential use of lambda light chains is associated with defective mouse antibody responses to the capsular polysaccharide of Neisseria meningitidis group B.

PubMed

Colino, Jesus; Outschoorn, Ingrid

2004-01-01

The capsular polysaccharide of Neisseria meningitidis group B (CpsB) is a very poor immunogen in mammals; this has been considered to be due to the induction of tolerance to cross-reactive host glycoconjugates. It has hampered the development of an effective vaccine against this meningococcal group for many years. Syngeneic populations have a similar tolerogenic background. Thus, we used the variability in ability to mount CpsB-specific immunoglobulin (Ig) responses of individuals from these populations to reveal underlying mechanisms to tolerance contributing to the poor immunogenicity of CpsB. Here we analyze by ELISA, the individual CpsB-specific Ig response of BALB/c and other syngeneic mice to immunization with intact bacteria, using the distribution of light chains as a direct indicator of the repertoire dynamics of the response. Although approximately 96% of anti-CpsB Ig bear kappa-light chains, BALB/c mouse populations were heterogeneous in the light chain composition of their individual anti-CpsB Ig responses. The proportion of kappa and lambda-light chains used for anti-CpsB Ig was a private characteristic that remained relatively constant, for each individual, through repetitive immunizations regardless of the bacterial stimuli size. Despite the prevalence of individual use of kappa-light chains, 5% of BALB/c mice showed restricted usage of lambda-light chains in their CpsB-specific Ig responses, and an additional 11% use them significantly. The preferential use of lambda-light chains in these mice was strongly associated with defective IgM, and absent or barely detectable IgG anti-CpsB responses even after repetitive bacterial immunization. We conclude that differences in the private repertoire of specific Ig also contribute to mouse unresponsiveness to CpsB.

Involvement of an ent-copalyl diphosphate synthase in tissue-specific accumulation of specialized diterpenes in Andrographis paniculata.

PubMed

Misra, Rajesh Chandra; Garg, Anchal; Roy, Sudeep; Chanotiya, Chandan Singh; Vasudev, Prema G; Ghosh, Sumit

2015-11-01

Ent-labdane-related diterpene (ent-LRD) specialized (i.e. secondary) metabolites of the medicinal plant kalmegh (Andrographis paniculata) have long been known for several pharmacological activities. However, our understanding of the ent-LRD biosynthetic pathway has remained largely incomplete. Since ent-LRDs accumulate in leaves, we carried out a comparative transcriptional analysis using leaf and root tissues, and identified 389 differentially expressed transcripts, including 223 transcripts that were preferentially expressed in leaf tissue. Analysis of the transcripts revealed various specialized metabolic pathways, including transcripts of the ent-LRD biosynthetic pathway. Two class II diterpene synthases (ApCPS1 and ApCPS2) along with one (ApCPS1') and two (ApCPS2' and ApCPS2″) transcriptional variants that were the outcomes of alternative splicing of the precursor mRNA and alternative transcriptional termination, respectively, were identified. ApCPS1 and ApCPS2 encode for 832- and 817-amino acids proteins, respectively, and are phylogenetically related to the dicotyledons ent-copalyl diphosphate synthases (ent-CPSs). The spatio-temporal patterns of ent-LRD metabolites accumulation and gene expression suggested a likely role for ApCPS1 in general (i.e. primary) metabolism, perhaps by providing precursor for the biosynthesis of phytohormone gibberellin (GA). However, ApCPS2 is potentially involved in tissue-specific accumulation of ent-LRD specialized metabolites. Bacterially expressed recombinant ApCPS2 catalyzed the conversion of (E,E,E)-geranylgeranyl diphosphate (GGPP), the general precursor of diterpenes to ent-copalyl diphosphate (ent-CPP), the precursor of ent-LRDs. Taken together, these results advance our understanding of the tissue-specific accumulation of specialized ent-LRDs of medicinal importance. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Carotid Plaque Score and Risk of Cardiovascular Mortality in the Oldest Old: Results from the TOOTH Study.

PubMed

Hirata, Takumi; Arai, Yasumichi; Takayama, Michiyo; Abe, Yukiko; Ohkuma, Kiyoshi; Takebayashi, Toru

2018-01-01

Accumulating evidence suggests that predictability of traditional cardiovascular risk factors declines with advancing age. We investigated whether carotid plaque scores (CPSs) were associated with cardiovascular disease (CVD) death in the oldest old, and whether asymmetrical dimethylarginine (ADMA), a marker of endothelial dysfunction, moderated the association between the CPS and CVD death. We conducted a prospective cohort study of Japanese subjects aged ≥85 years without CVD at baseline. We followed this cohort for 6 years to investigate the association of CPS with CVD death via multivariable Cox proportional hazard analysis. We divided participants into three groups according to CPS (no, 0 points; low, 1.2-4.9 points; high, ≥5.0 points). The predictive value of CPS for estimating CVD death risk over CVD risk factors, including ADMA, was examined using C-statistics. We analyzed 347 participants (151 men, 196 women; mean age, 87.6 years), of which 135 (38.9%) had no carotid plaque at baseline, and 48 (13.8%) had high CPS. Of the total, 29 (8.4%) participants experienced CVD-related death during the study period. Multivariable analysis revealed a significant association of high CPS with CVD-related mortality relative to no CPS (hazard ratio, 3.90; 95% confidence interval: 1.47-10.39). ADMA was not associated with CVD death, but the significant association between CPS and CVD death was observed only in lower ADMA level. The addition of CPS to other risk factors improved the predictability of CVD death (p=0.032). High CPS correlated significantly with a higher CVD death risk in the oldest old with low cardiovascular risk. Ultrasound carotid plaque evaluation might facilitate risk evaluations of CVD death in the very old.

Use of simulated patients to evaluate combined oral contraceptive dispensing practices of community pharmacists.

PubMed

Obreli-Neto, Paulo Roque; Pereira, Leonardo Régis Leira; Guidoni, Camilo Molino; de Oliveira Baldoni, André; Marusic, Srecko; de Lyra-Júnior, Divaldo Pereira; de Almeida, Kelsen Luis; Pazete, Ana Claudia Montolezi; do Nascimento, Janaina Dutra; Kos, Mitja; Girotto, Edmarlon; Cuman, Roberto Kenji Nakamura

2013-01-01

Combined oral contraceptive (COC) use is the most commonly used reversible method of birth control. The incorrect use of COCs is frequent and one of the most common causes of unintended pregnancies. Community pharmacists (CPs) are in a strategic position to improve COC use because they are the last health professional to interact with patients before drug use. To evaluate the COC dispensing practices of CPs in a developing country. A cross-sectional study was conducted in community pharmacies of Assis and Ourinhos microregions, Brazil, between June 1, 2012, and October 30, 2012. Four simulated patients (SPs) (with counseled audio recording) visited community pharmacies with a prescription for Ciclo 21(®) (a COC containing ethinyl estradiol 30 mcg + levonorgestrel 15 mcg). The audio recording of every SP visit was listened to independently by 3 researchers to evaluate the COC dispensing practice. The percentage of CPs who performed a screening for safe use of COCs (i.e., taking of patients' medical and family history, and measuring of blood pressure) and provided counseling, as well as the quality of the screening and counseling, were evaluated. Of the 185 CPs contacted, 41 (22.2%) agreed to participate in the study and finished the study protocol. Only 3 CPs asked the SP a question (1 question asked by each professional), and all of the questions were closed-ended, viz., "do you smoke?" (n = 2) and "what is your age?" (n = 1). None of the CPs measured the patient's blood pressure. Six CPs provided counseling when dispensing COCs (drug dosing, 5 CPs; possible adverse effects, 2 CPs), and one CP provided counseling regarding both aspects. The CPs evaluated did not dispense COC appropriately and could influence in the occurrence of negatives therapeutic outcomes such as adverse effects and treatment failure.

Tetrazole amphiphile inducing growth of conducting polymers hierarchical nanostructures and their electromagnetic absorption properties

NASA Astrophysics Data System (ADS)

Xie, Aming; Sun, Mengxiao; Zhang, Kun; Xia, Yilu; Wu, Fan

2018-05-01

Conducting polymers (CPs) at nano scales endow materials with special optical, electrical, and magnetic properties. The crucial factor to construct and regulate the micro-structures of CPs is the inducing reagent, particular in its chemical structure, such active sites, self-assembling properties. In this paper, we design and synthesize an amphiphile bearing tetrazole moiety on its skeleton, and use this amphiphile as an inducing reagent to prepare and regulate the micro-structures of a series of CPs including polypyrrole, polyaniline, poly(3,4-ethylenedioxythiophene) and poly(p-phenylenediamine). Because of the unique electric properties of CPs and size effect, we next explored the electromagnetic absorption performances of these CPs nanostructures. A synergetic combination of electric loss and magnetic loss is used to explain the absorption mechanism of these CPs nano-structures.

Evaluation of contact precautions for methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus.

PubMed

Bardossy, Ana Cecilia; Alsafadi, Muhammad Yasser; Starr, Patricia; Chami, Eman; Pietsch, Jennifer; Moreno, Daniela; Johnson, Laura; Alangaden, George; Zervos, Marcus; Reyes, Katherine

2017-12-01

There are limited controlled data demonstrating contact precautions (CPs) prevent methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) infections in endemic settings. We evaluated changes in hospital-acquired MRSA and VRE infections after discontinuing CPs for these organisms. This is a retrospective study done at an 800-bed teaching hospital in urban Detroit. CPs for MRSA and VRE were discontinued hospital-wide in 2013. Data on MRSA and VRE catheter-associated urinary tract infections (CAUTIs), ventilator-associated pneumonia (VAP), central line-associated bloodstream infections (CLABSIs), surgical site infections (SSIs), and hospital-acquired MRSA bacteremia (HA-MRSAB) rates were compared before and after CPs discontinuation. There were 36,907 and 40,439 patients hospitalized during the two 12-month periods: CPs and no CPs. Infection rates in the CPs and no-CPs periods were as follows: (1) MRSA infections: VAP, 0.13 versus 0.11 (P = .84); CLABSI, 0.11 versus 0.19 (P = .45); SSI, 0 versus 0.14 (P = .50); and CAUTI, 0.025 versus 0.033 (P = .84); (2) VRE infections: CAUTI, 0.27 versus 0.13 (P = .19) and CLABSI, 0.29 versus 0.3 (P = .94); and (3) HA-MRSAB rates: 0.14 versus 0.11 (P = .55), respectively. Discontinuation of CPs did not adversely impact endemic MRSA and VRE infection rates. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

A Novel Method for Profiling and Quantifying Short- and Medium-Chain Chlorinated Paraffins in Environmental Samples Using Comprehensive Two-Dimensional Gas Chromatography-Electron Capture Negative Ionization High-Resolution Time-of-Flight Mass Spectrometry.

PubMed

Xia, Dan; Gao, Lirong; Zheng, Minghui; Tian, Qichang; Huang, Huiting; Qiao, Lin

2016-07-19

Chlorinated paraffins (CPs) are complex technical mixtures containing thousands of isomers. Analyzing CPs in environmental matrices is extremely challenging. CPs have broad, unresolved profiles when analyzed by one-dimensional gas chromatography (GC). Comprehensive two-dimensional GC (GC×GC) can separate CPs with a high degree of orthogonality. A novel method for simultaneously profiling and quantifying short- and medium-chain CPs, using GC×GC coupled with electron capture negative ionization high-resolution time-of-flight mass spectrometry, was developed. The method allowed 48 CP formula congener groups to be analyzed highly selectively in one injection through accurate mass measurements of the [M - Cl](-) ions in full scan mode. The correlation coefficients (R(2)) for the linear calibration curves for different chlorine contents were 0.982 for short-chain CPs and 0.945 for medium-chain CPs. The method was successfully used to determine CPs in sediment and fish samples. By using this method, with enhanced chromatographic separation and high mass resolution, interferences between CP congeners and other organohalogen compounds, such as toxaphene, are minimized. New compounds, with the formulas C9H14Cl6 and C9H13Cl7, were found in sediment and biological samples for the first time. The method was shown to be a powerful tool for the analysis of CPs in environmental samples.

Innovations in the management of child protection workers: building worker resilience.

PubMed

Yin, Robert T

2004-10-01

CPS staff work in a fishbowl. Parents, teachers, advocates, counselors, doctors, and lawyers frequently see themselves as experts in the field of CPS. Yet, few of them have had the experience of a CPS worker telling them how to do their job. The true potential for CPS work will not be realized until our communities decide to increase worker pay and reduce worker caseloads. Yet, if we choose to work under these conditions, it is our responsibility to find ways to survive them. The CPS workers unanimously reported that the overall impact of these progressive management strategies was to significantly reduce their stress. Given the serious threats, criticisms, and outrage thrown daily at CPS workers, it is imperative that managers act first to protect their worker's "best interests." It is my belief that all of the policy deviations described above are ethical. None of them put children at risk. I hope that policymakers will someday change the old-school, management policies that are pervasive within our bureaucracies. I do not promote a wanton disregard for policy compliance; however, I do promote change where change is due. In light of the enormous impact that CPS workers have on children and their families, it is crucial that CPS managers be allowed to create an atmosphere where workers can successfully do their work.

Neuropathic ocular pain due to dry eye is associated with multiple comorbid chronic pain syndromes

PubMed Central

Galor, Anat; Covington, Derek; Levitt, Alexandra E.; McManus, Katherine T.; Seiden, Benjamin; Felix, Elizabeth R.; Kalangara, Jerry; Feuer, William; Patin, Dennis J.; Martin, Eden R.; Sarantopoulos, Konstantinos D.; Levitt, Roy C.

2015-01-01

Recent data demonstrate that dry eye (DE) susceptibility and other chronic pain syndromes (CPS) such as chronic widespread pain, irritable bowel syndrome and pelvic pain, may share common heritable factors. Previously, we showed that DE patients describing more severe symptoms tended to report features of neuropathic ocular pain (NOP). We hypothesize that patients with a greater number of CPS would have a different DE phenotype compared to those with fewer CPS. We recruited a cohort of 154 DE patients from the Miami Veterans Affairs Hospital and defined high and low CPS groups by cluster analysis. In addition to worse non-ocular pain complaints and higher PTSD and depression scores (P<0.01), we found that the high CPS group reported more severe neuropathic-type DE symptoms compared to the low CPS group, including worse ocular pain assessed via 3 different pain scales (P<0.05), with similar objective corneal DE signs. This is the first study to demonstrate DE patients who manifest a greater number of comorbid CPS report more severe DE symptoms and features of NOP. These findings provide further evidence that NOP may represent a central pain disorder, and that shared mechanistic factors may underlie vulnerability to some forms of DE and other comorbid CPS. PMID:26606863

Prognostic scores in oesophageal or gastric variceal bleeding.

PubMed

Ohmann, C; Stöltzing, H; Wins, L; Busch, E; Thon, K

1990-05-01

Numerous scoring systems have been developed for the prediction of outcome of variceal bleeding; however, only a few have been evaluated adequately. The object of this study was to improve the classical Child-Pugh score (CPS) and to test other scores from the literature. Patients (n = 82) with endoscopically confirmed variceal bleeding and long-term sclerotherapy were included in the study. Linear logistic regression (LR) was applied to different sets of prognostic variables with regard to 30-day mortality. In addition, scores from the literature were evaluated on the data set. Performance was measured by the accuracy and receiver-operating characteristic curves. The application of LR to all five CPS variables (accuracy, 80%) was superior to the classical CPS (70%). LR with selection from the CPS variables or from other sets of variables resulted in no improvement. Compared with CPS only three scores from the literature, mainly based on subsets of the CPS variables, showed an improved accuracy. It is concluded that CPS is still a good scoring system; however, it can be improved by statistical analysis using the same variables.

Interactions between F-111 Fuselage Fuel Tank Sealants. Part 2. Variation in Performance Properties of Polysulfides after Contact with Polyester Degradation Products,

DTIC Science & Technology

1984-08-01

principally from sebacic acid and neopentyl glycol and that the most significant difference between the sealants was the greater proportion of trihydric...exhaustive hydrolysis of the polyesters would generate sebacic acid and neopentyl glycol , in practice ester units such as (1) which are terminated with both...slight to moderate swelling and softening of the polysulfides with PR-1422 being the most susceptible. Neopentyl glycol suppressed the swelling due to

Intumescent Reaction Mechanisms: An Analytic Model.

DTIC Science & Technology

1983-05-01

or amide (such as urea , melamine , dicyan- diamide, urea formaldehyde , etc.) is the release of nonflammable gases (CO2, E . etc.) that physically...mo)/dT Versus I/T (Polysulfide) 34 5-3 Fourier Series Representation of TGA Data for Polysulfide, DIP-30, EPON Resin , and Borax 40 5-4 Fourier Series...Representation of TGA Data for Part A, Part B, and Part A+B 41 5-S Fourier Series Representation of d(m/m )/dT for Polysul- fide, DIP-30, EPOI Resin

Coating processes for increasing the moisture resistance of polyurethane baffle material

NASA Technical Reports Server (NTRS)

Bilow, N.; Sawko, P.

1974-01-01

An investigation was conducted with the objective to improve the hydrolytic stability of reticulated polyurethane baffle material. This material is used in fuel tanks of aircraft and ground vehicles. The most commonly used foam of this type is hydrolytically unstable. Potential moisture barrier coatings which were evaluated include Parylene, epoxy-polysulfide, polyether based polyurethanes, polysulfides, polyolefin rubbers, and several other materials. Parylene coatings of at least 0.2 mil were found to provide the greatest improvement in hydrolytic stability.

Validity of the Modified Child Psychopathy Scale for Juvenile Justice Center Residents.

PubMed

Verschuere, Bruno; Candel, Ingrid; Van Reenen, Lique; Korebrits, Andries

2012-06-01

Adult psychopathy has proven to be an important clinical and forensic construct, but much less is known about juvenile psychopathy. In the present study, we examined the construct validity of the self report modified Child Psychopathy Scale mCPS; Lynam (Psychological Bulletin 120:(2), 209-234, 1997) in a sample of 57 adolescents residing in a Dutch juvenile justice center, aged between 13 and 22 years. The mCPS total score was reliably related to high externalizing problems, low empathy, high anger and aggression, high impulsivity, high (violent) delinquency, and high alcohol/drug use. Unique relations were found for the antisocial-impulsive (mCPS Factor 2), but not the callous-unemotional facet of psychopathy (mCPS Factor 1). Our findings support the validity of the mCPS in that it encompasses the antisocial-impulsive facet of psychopathy, but it is less clear whether the mCPS sufficiently captures the affective-interpersonal facet of psychopathy.

Conducting Polymers and Their Applications in Diabetes Management.

PubMed

Zhao, Yu; Cao, Luyao; Li, Lanlan; Cheng, Wen; Xu, Liangliang; Ping, Xinyu; Pan, Lijia; Shi, Yi

2016-10-26

Advances in conducting polymers (CPs) have promoted the development of diabetic monitoring and treatment, which is of great significance in human healthcare and modern medicine. CPs are special polymers with physical and electrochemical features resembling metals, inorganic semiconductors and non-conducting polymers. To improve and extend their properties, the fabrication of CPs and CP composites has attracted intensive attention in recent decades. Some CPs are biocompatible and suitable for biomedical use. Thus, the intriguing properties of CPs make wearable, noninvasive, continuous diabetes managing devices and other potential applications in diabetes possible in the near future. To highlight the recent advances of CPs and their derived materials (especially in conducting polymer hydrogels), here we discuss their fabrication and characterization, review the current state-of-the-art research in diabetes management based on these materials and describe current challenges as well as future potential research directions.

Restricted Authentication and Encryption for Cyber-physical Systems

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

Kirkpatrick, Michael S; Bertino, Elisa; Sheldon, Frederick T

2009-01-01

Cyber-physical systems (CPS) are characterized by the close linkage of computational resources and physical devices. These systems can be deployed in a number of critical infrastructure settings. As a result, the security requirements of CPS are different than traditional computing architectures. For example, critical functions must be identified and isolated from interference by other functions. Similarly, lightweight schemes may be required, as CPS can include devices with limited computing power. One approach that offers promise for CPS security is the use of lightweight, hardware-based authentication. Specifically, we consider the use of Physically Unclonable Functions (PUFs) to bind an access requestmore » to specific hardware with device-specific keys. PUFs are implemented in hardware, such as SRAM, and can be used to uniquely identify the device. This technology could be used in CPS to ensure location-based access control and encryption, both of which would be desirable for CPS implementations.« less

Conjugated Polymers/DNA Hybrid Materials for Protein Inactivation.

PubMed

Zhao, Likun; Zhang, Jiangyan; Xu, Huiming; Geng, Hao; Cheng, Yongqiang

2016-09-07

Chromophore-assisted light inactivation (CALI) is a powerful tool for analyzing protein functions due to the high degree of spatial and temporal resolution. In this work, we demonstrate a CALI approach based on conjugated polymers (CPs)/DNA hybrid material for protein inactivation. The target protein is conjugated with single-stranded DNA in advance. Single-stranded DNA can form CPs/DNA hybrid material with cationic CPs via electrostatic and hydrophobic interactions. Through the formation of CPs/DNA hybrid material, the target protein that is conjugated with DNA is brought into close proximity to CPs. Under irradiation, CPs harvest light and generate reactive oxygen species (ROS), resulting in the inactivation of the adjacent target protein. This approach can efficiently inactivate any target protein which is conjugated with DNA and has good specificity and universality, providing a new strategy for studies of protein function and adjustment of protein activity.

Conducting Polymers and Their Applications in Diabetes Management

PubMed Central

Zhao, Yu; Cao, Luyao; Li, Lanlan; Cheng, Wen; Xu, Liangliang; Ping, Xinyu; Pan, Lijia; Shi, Yi

2016-01-01

Advances in conducting polymers (CPs) have promoted the development of diabetic monitoring and treatment, which is of great significance in human healthcare and modern medicine. CPs are special polymers with physical and electrochemical features resembling metals, inorganic semiconductors and non-conducting polymers. To improve and extend their properties, the fabrication of CPs and CP composites has attracted intensive attention in recent decades. Some CPs are biocompatible and suitable for biomedical use. Thus, the intriguing properties of CPs make wearable, noninvasive, continuous diabetes managing devices and other potential applications in diabetes possible in the near future. To highlight the recent advances of CPs and their derived materials (especially in conducting polymer hydrogels), here we discuss their fabrication and characterization, review the current state-of-the-art research in diabetes management based on these materials and describe current challenges as well as future potential research directions. PMID:27792179

Inhibition of fipronil and nonane metabolism in human liver microsomes and human cytochrome P450 isoforms by chlorpyrifos.

PubMed

Joo, Hyun; Choi, Kyoungju; Rose, Randy L; Hodgson, Ernest

2007-01-01

Previous studies have established that chlorpyrifos (CPS), fipronil, and nonane can all be metabolized by human liver microsomes (HLM) and a number of cytochrome P450 (CYP) isoforms. However, metabolic interactions between these three substrates have not been described. In this study the effect of either coincubation or preincubation of CPS with HLM or CYP isoforms with either fipronil or nonane as substrate was investigated. In both co- and preincubation experiments, CPS significantly inhibited the metabolism of fipronil or nonane by HLM although CPS inhibited the metabolism of fipronil more effectively than that of nonane. CPS significantly inhibited the metabolism of fipronil by CYP3A4 as well as the metabolism of nonane by CYP2B6. In both cases, preincubation with CPS caused greater inhibition than coincubation, suggesting that the inhibition is mechanism based.

The effect of chromosomal polymorphisms on the outcomes of fresh IVF/ICSI-ET cycles in a Chinese population.

PubMed

Xu, Xiaojuan; Zhang, Rui; Wang, Wei; Liu, Hongfang; Liu, Lin; Mao, Bin; Zeng, Xiangwu; Zhang, Xuehong

2016-11-01

Chromosomal polymorphisms (CPs) have been reported to be associated with infertility; however, their effects on the outcomes of in vitro fertilization/intracytoplasmic sperm injection-embryo transfer (IVF/ICSI-ET) are still controversial. In this retrospective study, we aimed to evaluate the effect of CPs on IVF/ICSI-ET outcomes. To investigate whether CPs affected the outcomes of fresh IVF/ICSI-ET cycles in a Chinese population, we evaluated infertile couples with male carriers of CPs (n = 348), infertile couples with female carriers (n = 99), and unaffected couples (n = 400) who had received their first treatment cycles in our hospital between January 2013 and March 2015. CPs in either male or female carriers seemed to have adverse effects on IVF/ICSI-ET outcomes. CPs in male carriers affected outcomes mainly by decreasing the rates of fertilization, embryo cleavage, good quality embryos, clinical pregnancies, ongoing pregnancies, and deliveries as well as increasing the biochemical pregnancy rate (P < 0.05); CPs in female carriers affected outcomes only by lowering the embryo cleavage rate (P < 0.05). The mean fertilization rate of couples with male CP carriers undergoing IVF was significantly lower than that in those undergoing ICSI (61.1 versus 66.5 %, respectively; P = 0.0004). Our data provide evidence for the involvement of CPs in the poor outcomes of fresh IVF/ICSI-ET cycles in a Chinese population. The use of ICSI might improve outcomes by increasing the fertilization rate for men with CPs.

Conduct Problems Among Boston-Area Youth Following the 2013 Marathon Bombing: The Moderating Role of Prior Violent Crime Exposure.

PubMed

Crum, Kathleen I; Cornacchio, Danielle; Coxe, Stefany; Greif Green, Jennifer; Comer, Jonathan S

2017-01-01

A large body of work documents the heavy mental health burden of youth exposure to disasters, but the majority of this research has focused on posttraumatic stress and internalizing symptoms. Less is known about associations between disaster exposure and children's conduct problems (CPs), or variables that may moderate such relationships. Given well-documented links between CPs and children's exposure to community violence, youth with greater prior community violence exposure through residence in high-crime areas may be particularly vulnerable to the impacts of disaster exposure on CPs. We surveyed Boston-area caregivers (N = 460) in the first 6 months following the 2013 Marathon bombing on their children's event-related exposures, as well as CPs. To estimate prior violent crime exposure, children's neighborhoods were assigned corresponding violent crime rates obtained from the Federal Bureau of Investigation's uniform crime reporting statistics. Almost 1 in 6 Boston-area children assessed in this convenience sample showed clinically elevated CPs in the aftermath of the Boston Marathon bombing and subsequent manhunt. Prior violent crime exposure significantly moderated the link between children's manhunt exposure (but not bombing exposure) and child CPs. Manhunt exposure was related to increased CPs among children living in areas with high and medium (but not low) levels of prior violent crime. Children living in neighborhoods characterized by violent crime may be at particularly increased risk for developing CPs after violent manmade disasters. As most postdisaster child intervention efforts focus on posttraumatic stress, efforts are needed to develop programs targeting child CPs, particularly for youth dwelling in violent neighborhoods.

The Accuracy of Physicians' Clinical Predictions of Survival in Patients With Advanced Cancer.

PubMed

Amano, Koji; Maeda, Isseki; Shimoyama, Satofumi; Shinjo, Takuya; Shirayama, Hiroto; Yamada, Takeshi; Ono, Shigeki; Yamamoto, Ryo; Yamamoto, Naoki; Shishido, Hideki; Shimizu, Mie; Kawahara, Masanori; Aoki, Shigeru; Demizu, Akira; Goshima, Masahiro; Goto, Keiji; Gyoda, Yasuaki; Hashimoto, Kotaro; Otomo, Sen; Sekimoto, Masako; Shibata, Takemi; Sugimoto, Yuka; Morita, Tatsuya

2015-08-01

Accurate prognoses are needed for patients with advanced cancer. To evaluate the accuracy of physicians' clinical predictions of survival (CPS) and assess the relationship between CPS and actual survival (AS) in patients with advanced cancer in palliative care units, hospital palliative care teams, and home palliative care services, as well as those receiving chemotherapy. This was a multicenter prospective cohort study conducted in 58 palliative care service centers in Japan. The palliative care physicians evaluated patients on the first day of admission and followed up all patients to their death or six months after enrollment. We evaluated the accuracy of CPS and assessed the relationship between CPS and AS in the four groups. We obtained a total of 2036 patients: 470, 764, 404, and 398 in hospital palliative care teams, palliative care units, home palliative care services, and chemotherapy, respectively. The proportion of accurate CPS (0.67-1.33 times AS) was 35% (95% CI 33-37%) in the total sample and ranged from 32% to 39% in each setting. While the proportion of patients living longer than CPS (pessimistic CPS) was 20% (95% CI 18-22%) in the total sample, ranging from 15% to 23% in each setting, the proportion of patients living shorter than CPS (optimistic CPS) was 45% (95% CI 43-47%) in the total sample, ranging from 43% to 49% in each setting. Physicians tend to overestimate when predicting survival in all palliative care patients, including those receiving chemotherapy. Copyright © 2015 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

The design of a capsule polysaccharide conjugate vaccine against Campylobacter jejuni serotype HS15.

PubMed

Bertolo, Lisa; Ewing, Cheryl P; Maue, Alexander; Poly, Frederic; Guerry, Patricia; Monteiro, Mario A

2013-01-25

Campylobacter jejuni infection is now the main cause of diarrhea-related illnesses in humans. An efficacious vaccine for the traveler and developing world market would be welcomed. We are engaged in the discovery and characterization of serotype-specific C. jejuni capsule polysaccharides (CPSs) to study their role in virulence and as protective vaccine antigens. Our prototype conjugate vaccine with serotype HS23 CPS (strain 81-176) has been shown to fully protect non-human primates against diarrhea inflicted by C. jejuni HS23, but ultimately, a useful CPS-based vaccine will have to be multivalent. To this end, we describe here the creation of a CPS-conjugate vaccine against C. jejuni serotype HS15. Structural analysis revealed that a repeating block consisting of L-α-arabinofuranose (Ara) and 6-deoxy-L-α-gulo-heptopyranose (6d-gulo-Hep) comprised the CPS of serotype HS15 type strain ATCC 43442 [→3)-α-L-Araf-(1→3)-6d-L-α-gulo-Hepp(1→](n). Strategically, the non-reducing end of the CPS was activated and used in the attachment of CPS to CRM₁₉₇ to yield a conjugate vaccine. A serological assessment of the CPS(HS15)-CRM₁₉₇ conjugate with an anti-HS15 polyclonal antibody confirmed the conservation of antigenic epitopes, and subsequent inoculation of mice with CPS(HS15)-CRM₁₉₇ revealed that this conjugate was indeed capable of raising anti-CPS(HS15) antibodies. Copyright © 2012 Elsevier Ltd. All rights reserved.

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

Doan-Nguyen, Vicky V. T.; Subrahmanyam, Kota S.; Butala, Megan M.

Sulfur cathodes in conversion reaction batteries offer high gravimetric capacity but suffer from parasitic polysulfide shuttling. We demonstrate here that transition metal chalcogels of approximate formula MoS 3.4 achieve a high gravimetric capacity close to 600 mAh g –1 (close to 1000 mAh g –1 on a sulfur basis) as electrode materials for lithium-ion batteries. Transition metal chalcogels are amorphous and comprise polysulfide chains connected by inorganic linkers. The linkers appear to act as a “glue” in the electrode to prevent polysulfide shuttling. The Mo chalcogels function as electrodes in carbonate- and ether-based electrolytes, which further provides evidence of polysulfidemore » solubility not being a limiting issue. We employ X-ray spectroscopy and operando pair distribution function techniques to elucidate the structural evolution of the electrode. Raman and X-ray photoelectron spectroscopy track the chemical moieties that arise during the anion-redox-driven processes. As a result, we find the redox state of Mo remains unchanged across the electrochemical cycling and, correspondingly, the redox is anion-driven.« less

Effect of Nickel Coated Multi-Walled Carbon Nanotubes on Electrochemical Performance of Lithium-Sulfur Rechargeable Batteries.

PubMed

Wu, Xiao; Yao, Shanshan; Hou, Jinli; Jing, Maoxiang; Qian, Xinye; Shen, Xiangqian; Xiang, Jun; Xi, Xiaoming

2017-04-01

Conventional lithium-sulfur batteries suffer from severe capacity fade, which is induced by low electron conductivity and high dissolution of intermediated polysulfides. Recent studies have shown the metal (Pt, Au, Ni) as electrocatalyst of lithium polysulfides and improved the performance for lithium sulfur batteries. In this work, we present the nickel coated multi-walled carbon nanotubes (Ni-MWNTs) as additive materials for elemental sulfur positive electrodes for lithium-sulfur rechargeable batteries. Compared with MWNTs, the obtained Ni-MWNTs/sulfur composite cathode demonstrate a reversible specific capacity approaching 545 mAh after 200 cycles at a rate of 0.5C as well as improved cycling stability and excellent rate capacity. The improved electrochemical performance can be attributed to the fact the MWNTs shows a vital role on polysulfides adsorption and nickel has a catalytic effect on the redox reactions during charge–discharge process. Meanwhile, the Ni-MWNTs is a good electric conductor for sulfur cathode.

Garlic-Derived Organic Polysulfides and Myocardial Protection123

PubMed Central

Bradley, Jessica M; Organ, Chelsea L; Lefer, David J

2016-01-01

For centuries, garlic has been shown to exert substantial medicinal effects and is considered to be one of the best disease-preventative foods. Diet is important in the maintenance of health and prevention of many diseases including cardiovascular disease (CVD). Preclinical and clinical evidence has shown that garlic reduces risks associated with CVD by lowering cholesterol, inhibiting platelet aggregation, and lowering blood pressure. In recent years, emerging evidence has shown that hydrogen sulfide (H2S) has cardioprotective and cytoprotective properties. The active metabolite in garlic, allicin, is readily degraded into organic diallyl polysulfides that are potent H2S donors in the presence of thiols. Preclinical studies have shown that enhancement of endogenous H2S has an impact on vascular reactivity. In CVD models, the administration of H2S prevents myocardial injury and dysfunction. It is hypothesized that these beneficial effects of garlic may be mediated by H2S-dependent mechanisms. This review evaluates the current knowledge concerning the cardioprotective effects of garlic-derived diallyl polysulfides. PMID:26764335

Balancing surface adsorption and diffusion of lithium-polysulfides on nonconductive oxides for lithium–sulfur battery design

DOE PAGES

Tao, Xinyong; Wang, Jianguo; Liu, Chong; ...

2016-04-05

Lithium–sulfur batteries have attracted attention due to their six-fold specific energy compared with conventional lithium-ion batteries. Dissolution of lithium polysulfides, volume expansion of sulfur and uncontrollable deposition of lithium sulfide are three of the main challenges for this technology. State-of-the-art sulfur cathodes based on metal-oxide nanostructures can suppress the shuttle-effect and enable controlled lithium sulfide deposition. However, a clear mechanistic understanding and corresponding selection criteria for the oxides are still lacking. Herein, various nonconductive metal-oxide nanoparticle-decorated carbon flakes are synthesized via a facile biotemplating method. The cathodes based on magnesium oxide, cerium oxide and lanthanum oxide show enhanced cycling performance.more » Adsorption experiments and theoretical calculations reveal that polysulfide capture by the oxides is via monolayered chemisorption. Moreover, we show that better surface diffusion leads to higher deposition efficiency of sulfide species on electrodes. Lastly, oxide selection is proposed to balance optimization between sulfide-adsorption and diffusion on the oxides.« less

Investigation of the Li–S Battery Mechanism by Real-Time Monitoring of the Changes of Sulfur and Polysulfide Species during the Discharge and Charge

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

Zheng, Dong; Liu, Dan; Harris, Joshua B.

The mechanism of the sulfur cathode in Li-S batteries has been proposed. It was revealed by the real-time quantitative determination of polysulfide species and elemental sulfur by means of the high performance liquid chromatography in the course of the discharge and recharge of a Li-S battery. A three-step reduction mechanism including two chemical equilibrium reactions was proposed for the sulfur cathode discharge. The typical two-plateau discharge curve for sulfur cathode can be explained. A two-step oxidation mechanism for the Li 2S and Li 2S 2 with a single chemical equilibrium among soluble polysulfide ions was proposed. In conclusion, the chemicalmore » equilibrium among S 5 2-, S 6 2-, S 7 2- and S 8 2- throughout the entire oxidation process resulted for the single flat recharge curve in Li-S batteries.« less

Inhibiting Polysulfide Shuttle in Lithium-Sulfur Batteries through Low-Ion-Pairing Salts and a Triflamide Solvent.

PubMed

Shyamsunder, Abhinandan; Beichel, Witali; Klose, Petra; Pang, Quan; Scherer, Harald; Hoffmann, Anke; Murphy, Graham K; Krossing, Ingo; Nazar, Linda F

2017-05-22

The step-change in gravimetric energy density needed for electrochemical energy storage devices to power unmanned autonomous vehicles, electric vehicles, and enable low-cost clean grid storage is unlikely to be provided by conventional lithium ion batteries. Lithium-sulfur batteries comprising lightweight elements provide a promising alternative, but the associated polysulfide shuttle in typical ether-based electrolytes generates loss in capacity and low coulombic efficiency. The first new electrolyte based on a unique combination of a relatively hydrophobic sulfonamide solvent and a low ion-pairing salt, which inhibits the polysulfide shuttle, is presented. This system behaves as a sparingly solvating electrolyte at slightly elevated temperatures, where it sustains reversible capacities as high as 1200-1500 mAh g -1 over a wide range of current density (2C-C/5, respectively) when paired with a lithium metal anode, with a coulombic efficiency of >99.7 % in the absence of LiNO 3 additive. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Balancing surface adsorption and diffusion of lithium-polysulfides on nonconductive oxides for lithium-sulfur battery design

NASA Astrophysics Data System (ADS)

Tao, Xinyong; Wang, Jianguo; Liu, Chong; Wang, Haotian; Yao, Hongbin; Zheng, Guangyuan; Seh, Zhi Wei; Cai, Qiuxia; Li, Weiyang; Zhou, Guangmin; Zu, Chenxi; Cui, Yi

2016-04-01

Lithium-sulfur batteries have attracted attention due to their six-fold specific energy compared with conventional lithium-ion batteries. Dissolution of lithium polysulfides, volume expansion of sulfur and uncontrollable deposition of lithium sulfide are three of the main challenges for this technology. State-of-the-art sulfur cathodes based on metal-oxide nanostructures can suppress the shuttle-effect and enable controlled lithium sulfide deposition. However, a clear mechanistic understanding and corresponding selection criteria for the oxides are still lacking. Herein, various nonconductive metal-oxide nanoparticle-decorated carbon flakes are synthesized via a facile biotemplating method. The cathodes based on magnesium oxide, cerium oxide and lanthanum oxide show enhanced cycling performance. Adsorption experiments and theoretical calculations reveal that polysulfide capture by the oxides is via monolayered chemisorption. Moreover, we show that better surface diffusion leads to higher deposition efficiency of sulfide species on electrodes. Hence, oxide selection is proposed to balance optimization between sulfide-adsorption and diffusion on the oxides.

Balancing surface adsorption and diffusion of lithium-polysulfides on nonconductive oxides for lithium-sulfur battery design.

PubMed

Tao, Xinyong; Wang, Jianguo; Liu, Chong; Wang, Haotian; Yao, Hongbin; Zheng, Guangyuan; Seh, Zhi Wei; Cai, Qiuxia; Li, Weiyang; Zhou, Guangmin; Zu, Chenxi; Cui, Yi

2016-04-05

Lithium-sulfur batteries have attracted attention due to their six-fold specific energy compared with conventional lithium-ion batteries. Dissolution of lithium polysulfides, volume expansion of sulfur and uncontrollable deposition of lithium sulfide are three of the main challenges for this technology. State-of-the-art sulfur cathodes based on metal-oxide nanostructures can suppress the shuttle-effect and enable controlled lithium sulfide deposition. However, a clear mechanistic understanding and corresponding selection criteria for the oxides are still lacking. Herein, various nonconductive metal-oxide nanoparticle-decorated carbon flakes are synthesized via a facile biotemplating method. The cathodes based on magnesium oxide, cerium oxide and lanthanum oxide show enhanced cycling performance. Adsorption experiments and theoretical calculations reveal that polysulfide capture by the oxides is via monolayered chemisorption. Moreover, we show that better surface diffusion leads to higher deposition efficiency of sulfide species on electrodes. Hence, oxide selection is proposed to balance optimization between sulfide-adsorption and diffusion on the oxides.

Investigation of the Li–S Battery Mechanism by Real-Time Monitoring of the Changes of Sulfur and Polysulfide Species during the Discharge and Charge

DOE PAGES

Zheng, Dong; Liu, Dan; Harris, Joshua B.; ...

2016-09-09

The mechanism of the sulfur cathode in Li-S batteries has been proposed. It was revealed by the real-time quantitative determination of polysulfide species and elemental sulfur by means of the high performance liquid chromatography in the course of the discharge and recharge of a Li-S battery. A three-step reduction mechanism including two chemical equilibrium reactions was proposed for the sulfur cathode discharge. The typical two-plateau discharge curve for sulfur cathode can be explained. A two-step oxidation mechanism for the Li 2S and Li 2S 2 with a single chemical equilibrium among soluble polysulfide ions was proposed. In conclusion, the chemicalmore » equilibrium among S 5 2-, S 6 2-, S 7 2- and S 8 2- throughout the entire oxidation process resulted for the single flat recharge curve in Li-S batteries.« less

Balancing surface adsorption and diffusion of lithium-polysulfides on nonconductive oxides for lithium–sulfur battery design

PubMed Central

Tao, Xinyong; Wang, Jianguo; Liu, Chong; Wang, Haotian; Yao, Hongbin; Zheng, Guangyuan; Seh, Zhi Wei; Cai, Qiuxia; Li, Weiyang; Zhou, Guangmin; Zu, Chenxi; Cui, Yi

2016-01-01

Lithium–sulfur batteries have attracted attention due to their six-fold specific energy compared with conventional lithium-ion batteries. Dissolution of lithium polysulfides, volume expansion of sulfur and uncontrollable deposition of lithium sulfide are three of the main challenges for this technology. State-of-the-art sulfur cathodes based on metal-oxide nanostructures can suppress the shuttle-effect and enable controlled lithium sulfide deposition. However, a clear mechanistic understanding and corresponding selection criteria for the oxides are still lacking. Herein, various nonconductive metal-oxide nanoparticle-decorated carbon flakes are synthesized via a facile biotemplating method. The cathodes based on magnesium oxide, cerium oxide and lanthanum oxide show enhanced cycling performance. Adsorption experiments and theoretical calculations reveal that polysulfide capture by the oxides is via monolayered chemisorption. Moreover, we show that better surface diffusion leads to higher deposition efficiency of sulfide species on electrodes. Hence, oxide selection is proposed to balance optimization between sulfide-adsorption and diffusion on the oxides. PMID:27046216

Fluorescent carbon nanoparticles from Citrus sinensis as efficient sorbents for pollutant dyes.

PubMed

Adedokun, Oluwaseun; Roy, Anurag; Awodugba, Ayodeji O; Devi, P Sujatha

2017-02-01

Here, we report a simple, green and economic process for the synthesis of highly fluorescent carbon nanoparticles (CPs) through low-temperature carbonization of a fruit waste, Citrus sinensis peel. This approach allows the large-scale production of aqueous CPs dispersions without any additives and post-treatment processes. The as-prepared CPs were of small particle size, exhibited bright blue fluorescence under UV irradiation (λ max  = 365 nm) with excellent colloidal stability in water. The chemical composition, structure and morphology of the as-prepared CPs were analyzed using various spectroscopic techniques such as X-ray diffraction, transmission electron microscopy and raman spectroscopy. The formed CPs were turbostratic in nature, with a large number of functional groups on the surface. We explored the adsorption characteristics of the formed CPs for wastewater treatment. Because of the negative surface of the CPs, as evident from the zeta value, it is possible to use them for selective adsorption of the cationic dye methylene blue from a mixture of dyes. The equilibrium adsorption isotherm revealed that the Langmuir model better describes the adsorption process than the Freundlich model. As-prepared CPs rapidly adsorbed ~84% of the methylene blue within 1 min and can be regenerated and used repeatedly. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Quantum dots and duplex-specific nuclease enabled ultrasensitive detection and serotyping of Dengue viruses in one step in a single tube.

PubMed

Shen, Wei; Gao, Zhiqiang

2015-03-15

Leveraging on the enzymatic processing of Dengue virus (DV) RNA hybridized quantum dot-capped DNA capture probes (QD-CPs), an ultrasensitive assay for the detection and serotyping of DVs is described in the report. Briefly, DV-specific DNA CPs are first capped by QDs and then conjugated to magnetic beads. In a sample solution, strands of DV RNA form heteroduplexes with the QD-CPs on the magnetic beads. The CPs together with the QDs in the heteroduplexes are subsequently cleaved off the magnetic beads by a duplex-specific nuclease (DSN), releasing the QDs to the solution, freeing the target RNA strands, and availing them for another around of hybridization with the remaining QD-CPs. After removing the magnetic beads along with unreacted (uncleaved) QD-CPs by using a permanent magnet, ultrasensitive fluorescent detection of DV is realized through the cleaved QDs. Serotyping of DV is accomplished by a judicious design of the QD-CPs. The assay combines excellent signal generation by the highly fluorescent QDs and the effortlessness of utilizing magnetic beads in the removal of the unreacted QD-CPs. The highly efficient DSN cleavage in conjunction with its excellent mismatch discrimination ability permits serotyping of DVs in one tube with excellent sensitivity and selectivity. Copyright © 2014 Elsevier B.V. All rights reserved.

A new practice-driven approach to develop software in a cyber-physical system environment

NASA Astrophysics Data System (ADS)

Jiang, Yiping; Chen, C. L. Philip; Duan, Junwei

2016-02-01

Cyber-physical system (CPS) is an emerging area, which cannot work efficiently without proper software handling of the data and business logic. Software and middleware is the soul of the CPS. The software development of CPS is a critical issue because of its complicity in a large scale realistic system. Furthermore, object-oriented approach (OOA) is often used to develop CPS software, which needs some improvements according to the characteristics of CPS. To develop software in a CPS environment, a new systematic approach is proposed in this paper. It comes from practice, and has been evolved from software companies. It consists of (A) Requirement analysis in event-oriented way, (B) architecture design in data-oriented way, (C) detailed design and coding in object-oriented way and (D) testing in event-oriented way. It is a new approach based on OOA; the difference when compared with OOA is that the proposed approach has different emphases and measures in every stage. It is more accord with the characteristics of event-driven CPS. In CPS software development, one should focus on the events more than the functions or objects. A case study of a smart home system is designed to reveal the effectiveness of the approach. It shows that the approach is also easy to be operated in the practice owing to some simplifications. The running result illustrates the validity of this approach.

Electrical and magnetic properties of rock and soil

USGS Publications Warehouse

Scott, J.H.

1983-01-01

Field and laboratory measurements have been made to determine the electrical conductivity, dielectric constant, and magnetic permeability of rock and soil in areas of interest in studies of electromagnetic pulse propagation. Conductivity is determined by making field measurements of apparent resisitivity at very low frequencies (0-20 cps), and interpreting the true resistivity of layers at various depths by curve-matching methods. Interpreted resistivity values are converted to corresponding conductivity values which are assumed to be applicable at 10^2 cps, an assumption which is considered valid because the conductivity of rock and soil is nearly constant at frequencies below 10^2 cps. Conductivity is estimated at higher frequencies (up to 10^6 cps) by using statistical correlations of three parameters obtained from laboratory measurements of rock and soil samples: conductivity at 10^2 cps, frequency and conductivity measured over the range 10^2 to 10^6 cps. Conductivity may also be estimated in this frequency range by using field measurements of water content and correlations of laboratory sample measurements of the three parameters: water content, frequency, and conductivity measured over the range 10^2 to 10^6 cps. This method is less accurate because nonrandom variation of ion concentration in natural pore water introduces error. Dielectric constant is estimated in a similar manner from field-derived conductivity values applicable at 10^2 cps and statistical correlations of three parameters obtained from laboratory measurements of samples: conductivity measured at 10^2 cps, frequency, and dielectric constant measured over the frequency range 10^2 to 10^6 cps. Dielectric constant may also be estimated from field measurements of water content and correlations of laboratory sample measurements of the three parameters: water content, frequency, and dielectric constant measured from 10^2 to 10^6 cps, but again, this method is less accurate because of variation of ion concentration of pore water. Special laboratory procedures are used to measure conductivity and dielectric constant of rock and soil samples. Electrode polarization errors are minimized by using an electrode system that is electrochemically reversible-with ions in pore water.

How physician and community pharmacist perceptions of the community pharmacist role in Australian primary care influence the quality of collaborative chronic disease management.

PubMed

Rieck, Allison; Pettigrew, Simone

2013-01-01

Community pharmacists (CPs) have been changing their role to focus on patient-centred services to improve the quality of chronic disease management (CDM) in primary care. However, CPs have not been readily included in collaborative CDM with other primary care professionals such as physicians. There is little understanding of the CP role change and whether it affects the utilisation of CPs in primary care collaborative CDM. To explore physician and CP perceptions of the CP's role in Australian primary care and how these perceptions may influence the quality of physician/CP CDM programmes. Data were collected from physicians and CPs using semi-structured interviews. A qualitative methodology utilising thematic analysis was employed during data analysis. Qualitative methodology trustworthiness techniques, negative case analysis and member checking were utilised to substantiate the resultant themes. A total of 22 physicians and 22 CPs were interviewed. Strong themes emerged regarding the participant perceptions of the CP's CDM role in primary care. The majority of interviewed physicians perceived that CPs did not have the appropriate CDM knowledge to complement physician knowledge to provide improved CDM compared with what they could provide on their own. Most of the interviewed CPs expressed a willingness and capability to undertake CDM; however, they were struggling to provide sustainable CDM in the business setting within which they function in the primary care environment. Role theory was selected as it provided the optimum explanation of the resultant themes. First, physician lack of confidence in the appropriateness of CP CDM knowledge causes physicians to be confused about the role CPs would undertake in a collaborative CDM that would benefit the physicians and their patients. Thus, by increasing physician awareness of CP CDM knowledge, physicians may see CPs as suitable CDM collaborators. Second, CPs are experiencing role conflict and stress in trying to change their role. Strengthening the service business model may reduce these CP role issues and allow CPs to reach their full potential in CDM and improve the quality of collaborative CDM in Australian primary care.

Interaction of TiS 2 and Sulfur in Li-S Battery System

DOE PAGES

Sun, Ke; Zhang, Qing; Bock, David C.; ...

2017-04-21

With the ability to adsorb polysulfide, electronically conductive and electrochemically active TiS 2 is an effective multifunctional cathode additive to improve Li-S battery cycling performance. Furthermore, by using X-ray Photoelectron Spectroscopy (XPS), direct evidence is obtained to demonstrate the strong interaction between Li-polysulfide and TiS 2. The observation of Li signature on Li 2S 8 treated TiS 2 proves that the TiS 2 possesses the ability to adsorb Li-polysulfides species on its surface. An electron density transfer from Ti to Li and S is identified based on the positions of the peaks in the XPS spectrum before and after themore » interaction, which is consistent with the theoretically predicted polysulfide-TiS 2 interaction models in the literature. TiS 2 sample with 2.5x higher BET surface area is obtained by milling the raw TiS 2 particles and used as cathode additive in the sulfur electrode. Furthermore, in the presence of TiS 2 additive, long cycle life and improved sulfur utilization of Li-S cells under high rate discharge are demonstrated. In addition, we find that a uniform TiS 2 distribution in the sulfur-TiS 2 hybrid electrode is vital in determining its effectiveness in enhancing the performance of sulfur electrodes. Thus, by processing method and condition should be very important considerations in future development of sulfur electrodes with TiS 2 additive.« less

Impact of Cognitive Abilities and Prior Knowledge on Complex Problem Solving Performance - Empirical Results and a Plea for Ecologically Valid Microworlds.

PubMed

Süß, Heinz-Martin; Kretzschmar, André

2018-01-01

The original aim of complex problem solving (CPS) research was to bring the cognitive demands of complex real-life problems into the lab in order to investigate problem solving behavior and performance under controlled conditions. Up until now, the validity of psychometric intelligence constructs has been scrutinized with regard to its importance for CPS performance. At the same time, different CPS measurement approaches competing for the title of the best way to assess CPS have been developed. In the first part of the paper, we investigate the predictability of CPS performance on the basis of the Berlin Intelligence Structure Model and Cattell's investment theory as well as an elaborated knowledge taxonomy. In the first study, 137 students managed a simulated shirt factory ( Tailorshop ; i.e., a complex real life-oriented system) twice, while in the second study, 152 students completed a forestry scenario ( FSYS ; i.e., a complex artificial world system). The results indicate that reasoning - specifically numerical reasoning (Studies 1 and 2) and figural reasoning (Study 2) - are the only relevant predictors among the intelligence constructs. We discuss the results with reference to the Brunswik symmetry principle. Path models suggest that reasoning and prior knowledge influence problem solving performance in the Tailorshop scenario mainly indirectly. In addition, different types of system-specific knowledge independently contribute to predicting CPS performance. The results of Study 2 indicate that working memory capacity, assessed as an additional predictor, has no incremental validity beyond reasoning. We conclude that (1) cognitive abilities and prior knowledge are substantial predictors of CPS performance, and (2) in contrast to former and recent interpretations, there is insufficient evidence to consider CPS a unique ability construct. In the second part of the paper, we discuss our results in light of recent CPS research, which predominantly utilizes the minimally complex systems (MCS) measurement approach. We suggest ecologically valid microworlds as an indispensable tool for future CPS research and applications.

The form variation of the capsular polysaccharide K1 is not a critical virulence factor of Escherichia coli in a neonatal mouse model of infection.

PubMed

Colino, J; Outschoorn, I

1999-10-01

Escherichia coli K1 is a prevalent cause of Gram-negative neonatal bacteraemia and meningitis in humans. Its capsular polysaccharide K1 (CpsK1) has been identified as an important virulence factor. Nevertheless, the biological and pathogenic implications of its O-acetylated and non-O-acetylated forms are poorly understood. In an attempt to address this, we monitored the expression of both CpsK1 form variants in a neonatal mouse infection model. In the absence of anti-CpsK1 antibodies, no CpsK1 form variant selection was observed during the course of infection. The administration of monoclonal antibodies specific for CpsK1 provided a high level of protection. The monoclonal antibodies that recognized both CpsK1 forms (MGB12) provided protection from up to 850 LD(50). By contrast, the administration of the monoclonal antibodies (MGB15) specific for non-O-acetylated CpsK1 cleared only bacteria expressing this CpsK1 form; a few mouse pups remained bacteraemic, and the bacteria in the blood had O-acetylated CpsK1. In those pups, the infection progressed in a similar fashion to that in mice not treated with monoclonal antibody. Moreover, when the number of bacteria expressing the O-acetylated CpsK1 in the inoculated dose is considered independently, the LD(50)was similar to that for the original strain in pups that had not been treated with monoclonal antibodies (35 CFU). These results suggest that whereas variation in acetylation form per se does not reinforce virulence, it could enable E. coli to avoid immune defenses. This highlights the importance of using highly specific monoclonal antibodies in immunotherapeutic approaches to E. coli K1 neonatal meningitis. Copyright 1999 Academic Press.

Use of Simulated Patients to Evaluate Combined Oral Contraceptive Dispensing Practices of Community Pharmacists

PubMed Central

Obreli-Neto, Paulo Roque; Pereira, Leonardo Régis Leira; Guidoni, Camilo Molino; Baldoni, André de Oliveira; Marusic, Srecko; de Lyra-Júnior, Divaldo Pereira; de Almeida, Kelsen Luis; Pazete, Ana Claudia Montolezi; do Nascimento, Janaina Dutra; Kos, Mitja; Girotto, Edmarlon; Cuman, Roberto Kenji Nakamura

2013-01-01

Background Combined oral contraceptive (COC) use is the most commonly used reversible method of birth control. The incorrect use of COCs is frequent and one of the most common causes of unintended pregnancies. Community pharmacists (CPs) are in a strategic position to improve COC use because they are the last health professional to interact with patients before drug use. Objective To evaluate the COC dispensing practices of CPs in a developing country. Method A cross-sectional study was conducted in community pharmacies of Assis and Ourinhos microregions, Brazil, between June 1, 2012, and October 30, 2012. Four simulated patients (SPs) (with counseled audio recording) visited community pharmacies with a prescription for Ciclo 21® (a COC containing ethinyl estradiol 30 mcg + levonorgestrel 15 mcg). The audio recording of every SP visit was listened to independently by 3 researchers to evaluate the COC dispensing practice. The percentage of CPs who performed a screening for safe use of COCs (i.e., taking of patients’ medical and family history, and measuring of blood pressure) and provided counseling, as well as the quality of the screening and counseling, were evaluated. Results Of the 185 CPs contacted, 41 (22.2%) agreed to participate in the study and finished the study protocol. Only 3 CPs asked the SP a question (1 question asked by each professional), and all of the questions were closed-ended, viz., “do you smoke?” (n = 2) and “what is your age?” (n = 1). None of the CPs measured the patient’s blood pressure. Six CPs provided counseling when dispensing COCs (drug dosing, 5 CPs; possible adverse effects, 2 CPs), and one CP provided counseling regarding both aspects. Conclusion The CPs evaluated did not dispense COC appropriately and could influence in the occurrence of negatives therapeutic outcomes such as adverse effects and treatment failure. PMID:24324584

Security and Privacy in Cyber-Physical Systems

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

Fink, Glenn A.; Edgar, Thomas W.; Rice, Theora R.

As you have seen from the previous chapters, cyber-physical systems (CPS) are broadly used across technology and industrial domains. While these systems enable process optimization and efficiency and allow previously impossible functionality, security and privacy are key concerns for their design, development, and operation. CPS have been key components utilized in some of the highest publicized security breaches over the last decade. In this chapter, we will look over the CPS described in the previous chapters from a security perspective. In this chapter, we explain classical information and physical security fundamentals in the context of CPS and contextualize them acrossmore » application domains. We give examples where the interplay of functionality and diverse communication can introduce unexpected vulnerabilities and produce larger impacts. We will discuss how CPS security and privacy is inherently different from that of pure cyber or physical systems and what may be done to secure these systems, considering their emergent cyber-physical properties. Finally, we will discuss security and privacy implications of merging infrastructural and personal CPS. Our hope is to impart the knowledge of what CPS security and privacy are, why they are important, and explain existing processes and challenges.« less

Cordyceps sinensis polysaccharide CPS-2 protects human mesangial cells from PDGF-BB-induced proliferation through the PDGF/ERK and TGF-β1/Smad pathways.

PubMed

Wang, Ying; Liu, Dan; Zhao, Huan; Jiang, Huixing; Luo, Chen; Wang, Min; Yin, Hongping

2014-02-15

CPS-2, a Cordyceps sinensis polysaccharide, has been demonstrated to have significant therapeutic activity against chronic renal failure. However, little is known about the underlying molecular mechanism. In this study, we found that CPS-2 could inhibit PDGF-BB-induced human mesangial cells (HMCs) proliferation in a dose-dependent manner. In addition, CPS-2 notably suppressed the expression of α-SMA, PDGF receptor-beta (PDGFRβ), TGF-β1, and Smad 3 in PDGF-BB-treated HMCs. Furthermore, PDGF-BB-stimulated ERK activation was significantly inhibited by CPS-2, and this inhibitory effect was synergistically potentiated by U0126. CPS-2 could prevent the PDGFRβ promoter activity induced by PDGF-BB, and return expression of PDGFRβ, TGF-β1, and TGFβRI to normal levels while cells were under PDGFRβ and ERK silencing conditions and transfected with DN-ERK. Taken together, these findings demonstrated that CPS-2 reduces PDGF-BB-induced cell proliferation through the PDGF/ERK and TGF-β1/Smad pathways, and it may have bi-directional regulatory effects on the PDGF/ERK cellular signaling pathway. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Dendritic Cell-Derived Exosomes Express a Streptococcus pneumoniae Capsular Polysaccharide Type 14 Cross-Reactive Antigen That Induces Protective Immunoglobulin Responses against Pneumococcal Infection in Mice

DTIC Science & Technology

2007-01-01

Microbiology. All Rights Reserved. Dendritic Cell-Derived Exosomes Express a Streptococcus pneumoniae Capsular Polysaccharide Type 14 Cross-Reactive...cross-reactive with the capsular polysaccharide of Streptococcus pneumoniae type 14 (Cps14-CRA). Cps14-CRA was localized to the cholesterol-enriched...for S. pneumoniae capsular polysaccharides (Cps) (17). More than 90 Cps sero- types have been described, with no cross-reaction among each other (16

Effect of developmental exposure to chlorpyrifos on the expression of neurotrophin growth factors and cell-specific markers in neonatal rat brain.

PubMed

Betancourt, Angela M; Burgess, Shane C; Carr, Russell L

2006-08-01

Chlorpyrifos (CPS), a known neurotoxicant, is a widely used agricultural organophosphorus insecticide. The effects of postnatal exposure to CPS on the expression of mRNA for two factors critical to brain development, nerve growth factor (NGF) and reelin, were investigated in the forebrain of rats. In addition, the expression of mRNA for the muscarinic acetylcholine receptor (mAChR) M(1) subtype and cell-specific markers for developing neurons (beta-III tubulin), astrocytes (glial fibrillary acidic protein, GFAP), and oligodendrocytes (myelin-associated glycoprotein, MAG) was also investigated. Oral administration of CPS (1.5 or 3.0 mg/kg) or the corn oil vehicle was performed daily from postnatal days (PNDs) 1 through 6. No signs of overt toxicity or of cholinergic hyperstimulation were observed after CPS administration. Body weight was significantly different from controls on PND7 in both males and females exposed to 3.0 mg/kg CPS. Quantitative PCR was performed on the forebrain. The expression of NGF, reelin, and M(1) mAChR mRNA was significantly reduced with both dosages of CPS in both sexes. beta-III Tubulin mRNA expression remained unchanged after exposure, whereas MAG mRNA expression was significantly decreased with both dosages of CPS in both sexes, suggesting effects on the developing oligodendrocytes. In contrast, GFAP mRNA levels were significantly increased with both dosages of CPS in both sexes, suggesting increased astrocyte reactivity. Our findings indicate that dosages of CPS which cause significant cholinesterase inhibition but do not exert overt toxicity can adversely affect the expression levels of critical genes involved in brain development during the early postnatal period in the rat.

Mutations blocking side chain assembly, polymerization, or transport of a Wzy-dependent Streptococcus pneumoniae capsule are lethal in the absence of suppressor mutations and can affect polymer transfer to the cell wall.

PubMed

Xayarath, Bobbi; Yother, Janet

2007-05-01

Extracellular polysaccharides of many bacteria are synthesized by the Wzy polymerase-dependent mechanism, where long-chain polymers are assembled from undecaprenyl-phosphate-linked repeat units on the outer face of the cytoplasmic membrane. In gram-positive bacteria, Wzy-dependent capsules remain largely cell associated via membrane and peptidoglycan linkages. Like many Wzy-dependent capsules, the Streptococcus pneumoniae serotype 2 capsule is branched. In this study, we found that deletions of cps2K, cps2J, or cps2H, which encode a UDP-glucose dehydrogenase necessary for side chain synthesis, the putative Wzx transporter (flippase), and the putative Wzy polymerase, respectively, were obtained only in the presence of suppressor mutations. Most of the suppressor mutations were in cps2E, which encodes the initiating glycosyltransferase for capsule synthesis. The cps2K mutants containing the suppressor mutations produced low levels of high-molecular-weight polymer that was detected only in membrane fractions. cps2K-repaired mutants exhibited only modest increases in capsule production due to the effect of the secondary mutation, but capsule was detectable in both membrane and cell wall fractions. Lethality of the cps2K, cps2J, and cps2H mutations was likely due to sequestration of undecaprenyl-phosphate in the capsule pathway and either preclusion of its turnover for utilization in essential pathways or destabilization of the membrane due to an accumulation of lipid-linked intermediates. The results demonstrate that proper polymer assembly requires not only a functional transporter and polymerase but also complete repeat units. A central role for the initiating glycosyltransferase in controlling capsule synthesis is also suggested.

Conduct Problems among Boston-Area Youth Following the 2013 Marathon Bombing: The moderating Role of Prior Violent Crime Exposure

PubMed Central

Crum, Kathleen I.; Cornacchio, Danielle; Coxe, Stefany; Green, Jennifer Greif; Comer, Jonathan S.

2017-01-01

A large body of work documents the heavy mental health burden of youth exposure to disasters, but the majority of this research has focused on posttraumatic stress and internalizing symptoms. Less is known about associations between disaster exposure and children’s conduct problems (CPs), or variables that may moderate such relationships. Given well-documented links between CPs and children’s exposure to community violence, youth with greater prior community violence exposure through residence in high-crime areas may be particularly vulnerable to the impacts of disaster exposure on CPs. We surveyed Boston-area caregivers (N=460) in the first 6 months following the 2013 Marathon bombing on their children’s event-related exposures, as well as CPs. To estimate prior violent crime exposure, children’s neighborhoods were assigned corresponding violent crime rates obtained from the Federal Bureau of Investigation’s uniform crime reporting statistics. Almost 1 in 6 Boston-area children assessed in this convenience sample showed clinically elevated CPs in the aftermath of the Boston Marathon bombing and subsequent manhunt. Prior violent crime exposure significantly moderated the link between children’s manhunt exposure (but not bombing exposure) and child CPs. Manhunt exposure was related to increased CPs among children living in areas with high and medium (but not low) levels of prior violent crime. Children living in neighborhoods characterized by violent crime may be at particularly increased risk for developing CPs after violent manmade disasters. As most post-disaster child intervention efforts focus on posttraumatic stress, efforts are needed to develop programs targeting child CPs, particularly for youth dwelling in violent neighborhoods. PMID:26630365

Synergistic Substrate Inhibition of ent-Copalyl Diphosphate Synthase: A Potential Feed-Forward Inhibition Mechanism Limiting Gibberellin Metabolism1[OA

PubMed Central

Prisic, Sladjana; Peters, Reuben J.

2007-01-01

Gibberellins (GAs) or gibberellic acids are ubiquitous diterpenoid phytohormones required for many aspects of plant growth and development, including repression of photosynthetic pigment production (i.e. deetiolation) in the absence of light. The committed step in GA biosynthesis is catalyzed in plastids by ent-copalyl diphosphate synthase (CPS), whose substrate, (E,E,E,)-geranylgeranyl diphosphate (GGPP), is also a direct precursor of carotenoids and the phytol side chain of chlorophyll. Accordingly, during deetiolation, GA production is repressed, whereas flux toward these photosynthetic pigments through their common GGPP precursor is dramatically increased. How this is accomplished has been unclear because no mechanism for regulation of CPS activity has been reported. We present here kinetic analysis of recombinant pseudomature CPS from Arabidopsis (Arabidopsis thaliana; rAtCPS) demonstrating that Mg2+ and GGPP exert synergistic substrate inhibition effects on CPS activity. These results suggest that GA metabolism may be limited by feed-forward inhibition of CPS; in particular, the effect of Mg2+ because light induces increases in plastid Mg2+ levels over a similar range as that observed here to affect rAtCPS activity. Notably, this effect is most pronounced in the GA-specific AtCPS because the corresponding activity of the resin acid biosynthetic enzyme abietadiene synthase is 100-fold less sensitive to [Mg2+]. Furthermore, Mg2+ allosterically activates the plant porphobilinogen synthase involved in chlorophyll production. Hence, Mg2+ may have a broad role in regulating plastidial metabolic flux during deetiolation. Finally, the observed synergistic substrate/feed-forward inhibition of CPS also seems to provide a novel example of direct regulation of enzymatic activity in hormone biosynthesis. PMID:17384166

Panel summary of cyber-physical systems (CPS) and Internet of Things (IoT) opportunities with information fusion

NASA Astrophysics Data System (ADS)

Blasch, Erik; Kadar, Ivan; Grewe, Lynne L.; Brooks, Richard; Yu, Wei; Kwasinski, Andres; Thomopoulos, Stelios; Salerno, John; Qi, Hairong

2017-05-01

During the 2016 SPIE DSS conference, nine panelists were invited to highlight the trends and opportunities in cyber-physical systems (CPS) and Internet of Things (IoT) with information fusion. The world will be ubiquitously outfitted with many sensors to support our daily living thorough the Internet of Things (IoT), manage infrastructure developments with cyber-physical systems (CPS), as well as provide communication through networked information fusion technology over the internet (NIFTI). This paper summarizes the panel discussions on opportunities of information fusion to the growing trends in CPS and IoT. The summary includes the concepts and areas where information supports these CPS/IoT which includes situation awareness, transportation, and smart grids.

Implementation of consumer providers into mental health intensive case management teams.

PubMed

Hamilton, Alison B; Chinman, Matthew; Cohen, Amy N; Oberman, Rebecca Shoai; Young, Alexander S

2015-01-01

In mental health care, consumer providers (CPs) are individuals with serious mental illness (SMI) who draw upon their lived experiences while providing services to others with SMI. Implementation of CPs has proven to be challenging in a variety of settings. The PEER project (Peers Enhancing Recovery) involved rolling out CPs using an implementation science model and evaluating implementation and impact in mental health treatment settings (three intervention, three control). In qualitative interviews, facilitators and challenges to implementation were described by the CPs, their team members, clients, and study researchers. Site preparation, external facilitation, and positive, reinforcing experiences with CPs facilitated implementation. Role definitions and deficiencies in CPs' technical knowledge posed challenges to implementation. Sustainability was not realized due to insufficient resources. However, implementation was positive overall, characterized by diffusion of innovation concepts of high relative advantage, strong trialability, compatibility with prevailing norms, compelling observability, and relatively low complexity. By preparing and working systematically with intervention sites to incorporate new services, implementation was strengthened and challenges were minimized.

Child Passenger Safety Training for Pediatric Interns: Does it Work?

PubMed

Morrissey, Dina; Riese, Alison; Violano, Pina; Lapidus, Garry; Baird, Janette; Mello, Michael J

2016-03-01

Evaluate the efficacy of a child passenger safety (CPS) educational intervention on the CPS-related knowledge, attitude and anticipatory guidance behaviors of pediatric interns. All subjects were surveyed at baseline and 6 months. Intervention interns attended a CPS training module which included viewing an educational video, observing a car seat inspection appointment, hands-on practice and completion of a post-intervention survey. All 16 intervention interns completed the initial survey, the intervention and the immediate-post questionnaire. Thirteen (81%) completed the 6-month follow-up. The baseline survey was completed by 27/40 (67%) of control interns, 28/40 (70%) submitted a follow-up. The proportion of intervention interns who self-reported giving CPS guidance at all well-child visits increased by 31.3% (95% CI 6.1,56.5%); the control group had no change. Similar results were seen with self-reported knowledge and attitude. A CPS training module increases pediatric interns' knowledge, improves attitudes, and self-reported behaviors regarding CPS-related anticipatory guidance.

Prospective study of Centurion® versus Infiniti® phacoemulsification systems: surgical and visual outcomes.

PubMed

Oh, Lawrence J; Nguyen, Chu Luan; Wong, Eugene; Wang, Samuel S Y; Francis, Ian C

2017-01-01

To evaluate surgical outcomes (SOs) and visual outcomes (VOs) in cataract surgery comparing the Centurion ® phacoemulsification system (CPS) with the Infiniti ® phacoemulsification system (IPS). Prospective, consecutive study in a single-site private practice. Totally 412 patients undergoing cataract surgery with either the CPS using the 30-degree balanced ® tip ( n =207) or the IPS using the 30-degree Kelman ® tip ( n =205). Intraoperative and postoperative outcomes were documented prospectively up to one month follow-up. Nuclear sclerosis (NS) grade, cumulated dissipated energy (CDE), preoperative corrected distance visual acuity (CDVA), and CDVA at one month were recorded. CDE was 13.50% less in the whole CPS compared with the whole IPS subcohort. In eyes with NS grade III or greater, CDE was 28.87% less with CPS ( n =70) compared with IPS ( n =44) ( P =0.010). Surgical complications were not statistically different between the two subcohorts ( P =0.083), but in the one case of vitreous loss using the CPS, CDVA of 6/4 was achieved at one month. The mean CDVAs (VOs) at one month for NS grade III and above cataracts were -0.17 logMAR (6/4.5) in the CPS and -0.15 logMAR (6/4.5) in the IPS subcohort respectively ( P =0.033). CDE is 28.87% less, and VOs are significantly improved, in denser cataracts in the CPS compared with the IPS. The authors recommend the CPS for cases with denser nuclei.

Capsule Polysaccharide Mediates Bacterial Resistance to Antimicrobial Peptides

PubMed Central

Campos, Miguel A.; Vargas, Miguel A.; Regueiro, Verónica; Llompart, Catalina M.; Albertí, Sebastián; Bengoechea, José A.

2004-01-01

The innate immune system plays a critical role in the defense of areas exposed to microorganisms. There is an increasing body of evidence indicating that antimicrobial peptides and proteins (APs) are one of the most important weapons of this system and that they make up the protective front for the respiratory tract. On the other hand, it is known that pathogenic organisms have developed countermeasures to resist these agents such as reducing the net negative charge of the bacterial membranes. Here we report the characterization of a novel mechanism of resistance to APs that is dependent on the bacterial capsule polysaccharide (CPS). Klebsiella pneumoniae CPS mutant was more sensitive than the wild type to human neutrophil defensin 1, β-defensin 1, lactoferrin, protamine sulfate, and polymyxin B. K. pneumoniae lipopolysaccharide O antigen did not play an important role in AP resistance, and CPS was the only factor conferring protection against polymyxin B in strains lacking O antigen. In addition, we found a significant correlation between the amount of CPS expressed by a given strain and the resistance to polymyxin B. We also showed that K. pneumoniae CPS mutant bound more polymyxin B than the wild-type strain with a concomitant increased in the self-promoted pathway. Taken together, our results suggest that CPS protects bacteria by limiting the interaction of APs with the surface. Finally, we report that K. pneumoniae increased the amount of CPS and upregulated cps transcription when grown in the presence of polymyxin B and lactoferrin. PMID:15557634

The Process of Solving Complex Problems

ERIC Educational Resources Information Center

Fischer, Andreas; Greiff, Samuel; Funke, Joachim

2012-01-01

This article is about Complex Problem Solving (CPS), its history in a variety of research domains (e.g., human problem solving, expertise, decision making, and intelligence), a formal definition and a process theory of CPS applicable to the interdisciplinary field. CPS is portrayed as (a) knowledge acquisition and (b) knowledge application…

46. C.P.S., photographer March 1936 MENDOCINO COUNTY, SECTION, HIGHWAY 1. ...

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

46. C.P.S., photographer March 1936 MENDOCINO COUNTY, SECTION, HIGHWAY 1. MEN-1-J#135, 384+50 81TTC2, LOOKING SOUTH LANES FLAT, C.P.S., 36. - Redwood National & State Parks Roads, California coast from Crescent City to Trinidad, Crescent City, Del Norte County, CA

Network Location-Aware Service Recommendation with Random Walk in Cyber-Physical Systems.

PubMed

Yin, Yuyu; Yu, Fangzheng; Xu, Yueshen; Yu, Lifeng; Mu, Jinglong

2017-09-08

Cyber-physical systems (CPS) have received much attention from both academia and industry. An increasing number of functions in CPS are provided in the way of services, which gives rise to an urgent task, that is, how to recommend the suitable services in a huge number of available services in CPS. In traditional service recommendation, collaborative filtering (CF) has been studied in academia, and used in industry. However, there exist several defects that limit the application of CF-based methods in CPS. One is that under the case of high data sparsity, CF-based methods are likely to generate inaccurate prediction results. In this paper, we discover that mining the potential similarity relations among users or services in CPS is really helpful to improve the prediction accuracy. Besides, most of traditional CF-based methods are only capable of using the service invocation records, but ignore the context information, such as network location, which is a typical context in CPS. In this paper, we propose a novel service recommendation method for CPS, which utilizes network location as context information and contains three prediction models using random walking. We conduct sufficient experiments on two real-world datasets, and the results demonstrate the effectiveness of our proposed methods and verify that the network location is indeed useful in QoS prediction.

Evaluation of the Immunomodulatory Properties of Streptococcus suis and Group B Streptococcus Capsular Polysaccharides on the Humoral Response

PubMed Central

Calzas, Cynthia; Taillardet, Morgan; Fourati, Insaf Salem; Roy, David; Gottschalk, Marcelo; Soudeyns, Hugo; Defrance, Thierry; Segura, Mariela

2017-01-01

Streptococcus suis and group B Streptococcus (GBS) are encapsulated streptococci causing septicemia and meningitis. Antibodies (Abs) against capsular polysaccharides (CPSs) have a crucial protective role, but the structure/composition of the CPS, including the presence of sialic acid, may interfere with the generation of anti-CPS Ab responses. We investigated the features of the CPS-specific Ab response directed against S. suis serotypes 2 and 14 and GBS serotypes III and V after infection or immunization with purified native or desialylated CPSs in mice. Whereas S. suis-infected mice developed a very low/undetectable CPS-specific IgM response, significant anti-CPS IgM titers were measured in GBS-infected animals (especially for type III GBS). No isotype switching was detected in S. suis- or GBS-infected mice. While the expression of sialic acid was essential for the immunogenicity of purified GBS type III CPS, this sugar was not responsible for the inability of purified S. suis types 2, 14 and GBS type V CPSs to induce a specific Ab response. Thus, other biochemical criteria unrelated to the presence of sialic acid may be responsible for the inaptitude of the host immune system to mount an effective response against certain S. suis and GBS CPS types. PMID:28425925

Congenital portosystemic shunts associated with liver tumours.

PubMed

Pupulim, L F; Vullierme, M-P; Paradis, V; Valla, D; Terraz, S; Vilgrain, V

2013-07-01

To evaluate the diagnosis and presentation of liver tumours in patients with congenital portosystemic shunts (CPS). Eight patients were diagnosed in Hôpital Beaujon as having CPS. All patients underwent Doppler ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), and histological examination of liver tumours. CPS were classified according to anatomy and the amount of portal flow deviated to the systemic circulation as: total, subtotal, or partial. Liver tumours were diagnosed by needle core biopsy (n = 5) or surgery (n = 3). Clinical follow-up was available in all patients but one (mean follow-up 36 months; range 1-5 years). Six patients had total CPS, one patient had a subtotal CPS, and the last had a partial CPS. All patients presented with multiple liver nodules (range four to >15). The tumours were characterized as focal nodular hyperplasia (FNH; n = 4), FNH with hepatocellular adenoma (n = 2), and regenerative nodular hyperplasia (n = 2). In four of seven patients (57%) that had follow-up, tumours showed enlargement or new lesions appeared. In this series of CPS patients, tumours were all benign, multiple, and of hepatocellular origin, and different tumours were present simultaneously in two patients. Tumour enlargement or new nodules were common during follow-up. Copyright © 2013 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

AERORADIOACTIVITY SURVEY AND AREAL GEOLOGY OF THE GEORGIA NUCLEAR LABORATORY AREA, NORTHERN GEORGIA (ARMS-I)

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

MacKallor, J.A.

1962-01-01

An airborne gamma-radioactivity survey of about 7000 square miles around the Georgia Nuclear Laboratory (GNL) in Dawson County, Ga., was made by the U. S. Geological Survey in cooperation with the Division of Biology and Medicine, U. S. Atomic Energy Commission. The project was flown perpendicular to the regional strike at a nominal elevation of 500 ft above the ground with a flight-line spacing of 1 mile. Radioactivity contacts shown on a 1:250,000 map delineate areas of similar radioactivity, which, in general, trend northeast, parallel to the geologic strike. Many, but not all, formations correlate closely with radioactivity units. Changesmore » of radioactivity within some formations may indicate facies changes. In the GNL area the Cartersville fault, which dlosely coincides with a prominent radioactivity contact, separates the Valley and Ridge physiographic province from the Piedmont to the east. Within the Valley and Ridge province bedrock consists of sedimentary rocks of Paleozoic age; the radioactivity is from 300 to 900 counts per second (cps). Areas of limestone and dolomite are characterized by radioactivity lows, usually less than 500 cps. Most areas of shale have a radioactivity of 600 to 900 cps. Bedrock in the Piedmont consists mainly of igneous and metamorphic rocks of Precambrian and Palezoic ages, and the radioactivity ranges from about 250 to 2000 cps. The least radioactive rocks (250 to 500 cps) are hornblende gneiss, dioritic injection gneiss, and some of the granitic gneiss. The most radioactive rock is the augen gneiss in Bartow and Cherokee Counties (1000 to 2000 cps). Some of the granitic gneiss, biotite gneiss and schist, and the Talladega Slate have a radioactivity of slightly more than 1000 cps. Composite samples of surficial material were collected from sites directly under the flight path of the aircraft. After analysis for equivalent uranium based upon the number of counts recorded by geiger tubes, the samples were stored for future reference. The equivalent uranium was plotted against cps obtained from the aerial surveying. From 600 cps, which corresponds to slightiy more than 0.001 percent equivalent uranium, to 1600 cps, each 200-cps increase corresponds to an increase of almost 0.001 percent equivalent uranium. (auth)« less

The performance of approximations of farm contiguity compared to contiguity defined using detailed geographical information in two sample areas in Scotland: implications for foot-and-mouth disease modelling.

PubMed

Flood, Jessica S; Porphyre, Thibaud; Tildesley, Michael J; Woolhouse, Mark E J

2013-10-08

When modelling infectious diseases, accurately capturing the pattern of dissemination through space is key to providing optimal recommendations for control. Mathematical models of disease spread in livestock, such as for foot-and-mouth disease (FMD), have done this by incorporating a transmission kernel which describes the decay in transmission rate with increasing Euclidean distance from an infected premises (IP). However, this assumes a homogenous landscape, and is based on the distance between point locations of farms. Indeed, underlying the spatial pattern of spread are the contact networks involved in transmission. Accordingly, area-weighted tessellation around farm point locations has been used to approximate field-contiguity and simulate the effect of contiguous premises (CP) culling for FMD. Here, geographic data were used to determine contiguity based on distance between premises' fields and presence of landscape features for two sample areas in Scotland. Sensitivity, positive predictive value, and the True Skill Statistic (TSS) were calculated to determine how point distance measures and area-weighted tessellation compared to the 'gold standard' of the map-based measures in identifying CPs. In addition, the mean degree and density of the different contact networks were calculated. Utilising point distances <1 km and <5 km as a measure for contiguity resulted in poor discrimination between map-based CPs/non-CPs (TSS 0.279-0.344 and 0.385-0.400, respectively). Point distance <1 km missed a high proportion of map-based CPs; <5 km point distance picked up a high proportion of map-based non-CPs as CPs. Area-weighted tessellation performed best, with reasonable discrimination between map-based CPs/non-CPs (TSS 0.617-0.737) and comparable mean degree and density. Landscape features altered network properties considerably when taken into account. The farming landscape is not homogeneous. Basing contiguity on geographic locations of field boundaries and including landscape features known to affect transmission into FMD models are likely to improve individual farm-level accuracy of spatial predictions in the event of future outbreaks. If a substantial proportion of FMD transmission events are by contiguous spread, and CPs should be assigned an elevated relative transmission rate, the shape of the kernel could be significantly altered since ability to discriminate between map-based CPs and non-CPs is different over different Euclidean distances.

Curing of polymer thermosets via click reactions and on demand processes

NASA Astrophysics Data System (ADS)

Brei, Mark Richard

In the first project, an azide functional resin and tetra propargyl aromatic diamines were fabricated for use as a composite matrix. These systems take already established epoxy/amine matrices and functionalize them with click moieties. This allows lower temperatures to be used in the production of a thermoset part. These new systems yield many better mechanical properties than their epoxy/amine derivatives, but their Tgs are low in comparison. The second project investigates the characterization of a linear system based off of the above azide functional resin and a difunctional alkyne. Through selectively choosing catalyst, the linear system can show regioselectivity to either a 1,4-disubstituted triazole, or a 1,5-disubstituted triazole. Without the addition of catalyst, the system produces both triazoles in almost an equal ratio. The differently catalyzed systems were cured and then analyzed by 1H and 13C NMR to better understand the structure of the material. The third project builds off of the utility of the aforementioned azide/alkyne system and introduces an on-demand aspect to the curing of the thermoset. With the inclusion of copper(II) within the azide/alkyne system, UV light is able to catalyze said reaction and cure the material. It has been shown that the copper(II) loading levels can be extremely small, which helps in reducing the copper's effect on mechanical properties The fourth project takes a look at polysulfide-based sealants. These sealants are normally cured via an oxidative reaction. This project took thiol-terminated polysulfides and fabricated alkene-terminated polysulfides for use as a thiol-ene cured material. By changing the mechanism for cure, the polysulfide can be cured via UV light with the use of a photoinitiator within the thiol/alkene polysulfide matrix. The final chapter will focus on a characterization technique, MALDI-TOF, which was used to help characterize the above materials as well as many others. By using MALDI-TOF, the researcher is able to elicit the molecular weight of the repeat unit and end group, which allows the determination of the polymer's structure. This technique can also determine the Mn and M w, as well as the PDI for each given polymer.

Development and evaluation of in situ gel of pregabalin

PubMed Central

Madan, Jyotsana R; Adokar, Bhushan R; Dua, Kamal

2015-01-01

Aim and Background: Pregabalin (PRG), an analog of gamma-aminobutyric acid, reduces the release of many neurotransmitters, including glutamate, and noradrenaline. It is used for the treatment of epilepsy; simple and complex partial convulsion. The present research work aims to ensure a high drug absorption by retarding the advancement of PRG formulation through the gastrointestinal tract. The work aims to design a controlled release PRG formulation which is administered as liquid and further gels in the stomach and floats in gastric juice. Materials and Methods: In situ gelling formulations were prepared using sodium alginate, calcium chloride, sodium citrate, hydroxypropyl methylcellulose (HPMC) K100M, and sodium bicarbonate. The prepared formulations were evaluated for solution viscosity, drug content, in vitro gelling studies, gel strength, and in vitro drug release. The final formulation was optimized using a 32 full factorial design. Results: The formulation containing 2.5% w/v sodium alginate and 0.2% w/v calcium chloride were considered optimum since it showed minimum floating lag time (18 s), optimum viscosity (287.3 cps), and gel strength (4087.17 dyne/cm2). The optimized formulation follows Korsmeyer-Peppas kinetic model with n value 0.3767 representing Fickian diffusion mechanism of drug release. Conclusion: Floating in situ gelling system of PRG can be formulated using sodium alginate as a gelling polymer and calcium chloride as a complexing agent to control the drug release for about 12 h for the treatment of epilepsy. PMID:26682193

Impact of Cognitive Abilities and Prior Knowledge on Complex Problem Solving Performance – Empirical Results and a Plea for Ecologically Valid Microworlds

PubMed Central

Süß, Heinz-Martin; Kretzschmar, André

2018-01-01

The original aim of complex problem solving (CPS) research was to bring the cognitive demands of complex real-life problems into the lab in order to investigate problem solving behavior and performance under controlled conditions. Up until now, the validity of psychometric intelligence constructs has been scrutinized with regard to its importance for CPS performance. At the same time, different CPS measurement approaches competing for the title of the best way to assess CPS have been developed. In the first part of the paper, we investigate the predictability of CPS performance on the basis of the Berlin Intelligence Structure Model and Cattell’s investment theory as well as an elaborated knowledge taxonomy. In the first study, 137 students managed a simulated shirt factory (Tailorshop; i.e., a complex real life-oriented system) twice, while in the second study, 152 students completed a forestry scenario (FSYS; i.e., a complex artificial world system). The results indicate that reasoning – specifically numerical reasoning (Studies 1 and 2) and figural reasoning (Study 2) – are the only relevant predictors among the intelligence constructs. We discuss the results with reference to the Brunswik symmetry principle. Path models suggest that reasoning and prior knowledge influence problem solving performance in the Tailorshop scenario mainly indirectly. In addition, different types of system-specific knowledge independently contribute to predicting CPS performance. The results of Study 2 indicate that working memory capacity, assessed as an additional predictor, has no incremental validity beyond reasoning. We conclude that (1) cognitive abilities and prior knowledge are substantial predictors of CPS performance, and (2) in contrast to former and recent interpretations, there is insufficient evidence to consider CPS a unique ability construct. In the second part of the paper, we discuss our results in light of recent CPS research, which predominantly utilizes the minimally complex systems (MCS) measurement approach. We suggest ecologically valid microworlds as an indispensable tool for future CPS research and applications. PMID:29867627

Site-directed mutagenesis studies on the uridine monophosphate binding sites of feedback inhibition in carbamoyl phosphate synthetase and effects on cytidine production by Bacillus amyloliquefaciens.

PubMed

Fang, Haitian; Liu, Huiyan; Chen, Ning; Zhang, Chenglin; Xie, Xixian; Xu, Qingyang

2013-06-01

A major problem when pyrimidine de novo biosynthesis is used for cytidine production is the existence of many negative regulatory factors. Cytidine biosynthesis in Bacillus amyloliquefaciens proceeds via a pathway that is controlled by uridine monophosphate (UMP) through feedback inhibition of carbamoyl phosphate synthetase (CPS), the enzyme that converts CO2, NH3, and glutamine to carbamoyl phosphate. In this study, the gene carB encoding the large subunit of CPS from B. amyloliquefaciens CYT1 was site directed, and the UMP binding sites of feedback inhibition in Bam-CPS are described. The residues Thr-941, Thr-970, and Lys-986 in CPS from B. amyloliquefaciens were subjected to site-directed mutagenesis to alter UMP's feedback inhibition of CPS. To find feedback-resistant B. amyloliquefaciens, the influence of the T941F, T970A, K986I, T941F/K986I, and T941F/T970A/K986I mutations on CPS enzymatic properties was studied. The recombinant B. amyloliquefaciens with mutated T941F/K986I and T941F/T970A/K986I CPS showed a 3.7- and 5.7-fold increase, respectively, in cytidine production in comparison with the control expressing wild-type CPS, which was more suitable for further application of the cytidine synthesis. To a certain extent, the 5 mutations were found to release the enzyme from UMP inhibition and to improve B. amyloliquefaciens cytidine-producing strains.

Prospective study of Centurion® versus Infiniti® phacoemulsification systems: surgical and visual outcomes

PubMed Central

Oh, Lawrence J.; Nguyen, Chu Luan; Wong, Eugene; Wang, Samuel S.Y.; Francis, Ian C.

2017-01-01

AIM To evaluate surgical outcomes (SOs) and visual outcomes (VOs) in cataract surgery comparing the Centurion® phacoemulsification system (CPS) with the Infiniti® phacoemulsification system (IPS). METHODS Prospective, consecutive study in a single-site private practice. Totally 412 patients undergoing cataract surgery with either the CPS using the 30-degree balanced® tip (n=207) or the IPS using the 30-degree Kelman® tip (n=205). Intraoperative and postoperative outcomes were documented prospectively up to one month follow-up. Nuclear sclerosis (NS) grade, cumulated dissipated energy (CDE), preoperative corrected distance visual acuity (CDVA), and CDVA at one month were recorded. RESULTS CDE was 13.50% less in the whole CPS compared with the whole IPS subcohort. In eyes with NS grade III or greater, CDE was 28.87% less with CPS (n=70) compared with IPS (n=44) (P=0.010). Surgical complications were not statistically different between the two subcohorts (P=0.083), but in the one case of vitreous loss using the CPS, CDVA of 6/4 was achieved at one month. The mean CDVAs (VOs) at one month for NS grade III and above cataracts were -0.17 logMAR (6/4.5) in the CPS and -0.15 logMAR (6/4.5) in the IPS subcohort respectively (P=0.033). CONCLUSION CDE is 28.87% less, and VOs are significantly improved, in denser cataracts in the CPS compared with the IPS. The authors recommend the CPS for cases with denser nuclei. PMID:29181313

Differences in Child Passenger Safety Counseling Frequency and Attitudes by Health Care Provider Specialty.

PubMed

Huseth-Zosel, Andrea L; Orr, Megan

2016-12-01

Many children are not being properly restrained in motor vehicles, resulting in unnecessary injury and fatalities. Health care provider (HCP) education is effective at increasing proper child restraint within vehicles. However, differences exist by HCP specialty in regards to frequency of child passenger safety (CPS) counseling. This study of a sample of 255 HCPs examined differences in CPS counseling by HCP specialty (pediatric vs. non-pediatric). HCPs from several upper Midwest states were surveyed about how frequently they provide CPS counseling in their practice by patient age and their attitudes toward CPS-related issues. Pediatric HCPs were twice as likely as non-pediatric HCPs to always provide CPS counseling to parents/guardians of children aged 5 or older. Non-pediatric HCPs were more likely than pediatric HCPs to feel that counseling is ineffective at increasing child seat/booster (p = 0.001) or seat belt use (p = 0.006). Non-pediatric HCPs were more likely than pediatric HCPs to feel there is inadequate time to provide CPS counseling in their practice setting (p = 0.001), and were less likely to know where to refer patients if they have questions regarding CPS issues (0.0291). The differences in HCP attitudes toward CPS counseling provision and the resulting differences in counseling frequency by patient age may contribute to disparities for patients who have limited or no access to pediatric HCPs. Additional research is needed to investigate the rationale for counseling differences seen by HCP specialty and patient age, and the potential effect on child motor vehicle injuries and fatalities.

Understanding the bacterial polysaccharide antigenicity of Streptococcus agalactiae versus Streptococcus pneumoniae.

PubMed

Kadirvelraj, Renuka; Gonzalez-Outeiriño, Jorge; Foley, B Lachele; Beckham, Meredith L; Jennings, Harold J; Foote, Simon; Ford, Michael G; Woods, Robert J

2006-05-23

Bacterial surface capsular polysaccharides (CPS) that are similar in carbohydrate sequence may differ markedly in immunogenicity and antigenicity. The structural origin of these phenomena is poorly understood. Such a case is presented by the Gram-positive bacteria Streptococcus agalactiae (Group B Streptococcus; GBS) type III (GBSIII) and Streptococcus pneumoniae (Pn) type 14 (Pn14), which share closely related CPS sequences. Nevertheless, antibodies (Abs) against GBSIII rarely cross-react with the CPS from Pn14. To establish the origin for the variation in CPS antigenicity, models for the immune complexes of CPS fragments from GBSIII and Pn14, with the variable fragment (Fv) of a GBS-specific mAb (mAb 1B1), are presented. The complexes are generated through a combination of comparative Ab modeling and automated ligand docking, followed by explicitly solvated 10-ns molecular dynamics simulations. The relationship between carbohydrate sequence and antigenicity is further quantified through the computation of interaction energies using the Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) method, augmented by conformational entropy estimates. Despite the electrostatic differences between Pn14 and GBSIII CPS, analysis indicates that entropic penalties are primarily responsible for the loss of affinity of the highly flexible Pn14 CPS for mAb 1B1. The similarity of the solution conformation of the relatively rigid GBSIII CPS with that in the immune complex characterizes the previously undescribed 3D structure of the conformational epitope. The analysis provides a comprehensive interpretation for a large body of biochemical and immunological data related to Ab recognition of bacterial polysaccharides and should be applicable to other Ab-carbohydrate interactions.

Community pharmacists' perspectives of online health-related information: A qualitative insight from Kuala Lumpur, Malaysia.

PubMed

See Wan, Ong; Hassali, Mohamed Azmi; Saleem, Fahad

2017-01-01

The Internet is a resource used by health professionals as well as the public to access health information. Within this context, little is reported on community pharmacists' (CPs') perceptions of online health-related information. The objective of this study was to explore the attitudes of Malaysian CPs towards online health-related information. A qualitative research method was adopted with face-to-face interviews, using a semi-structured interview guide. Purposive and snowball sampling techniques were used to recruit a convenient sample of CPs who were practising in the Federal Territory of Kuala Lumpur, Malaysia. All interviews were audio recorded and transcribed verbatim. The data were analysed by the research team using a thematic content analysis framework. Eleven CPs participated in the study. Participants reported that online health-related information was accessible, useful, fast, and in some respects, the Internet is a unique source of information. It was reported that there was a need to establish websites for trusted information. CPs also reported that training was needed in Internet searching and website evaluation skills. Most information accessed by CPs related to drugs and diseases and to knowledge-based information. Barriers to efficacy of Internet usage were related to the reliability and volume of information available on the Internet. Frequent use of online health-related information among CPs was reported. Many CPs supported the use of the Internet for health-related information but certain reservations were also reported. An analysis of the reasons for information seeking and barriers suggests that a wider range of influences on health information seeking should be investigated.

Child, caregiver, and family characteristics associated with emergency department use by children who remain at home after a child protective services investigation

PubMed Central

Hurlburt, Michael S.; Leslie, Laurel K.; Zhang, Jinjin; Horwitz, Sarah McCue

2012-01-01

Objectives To examine emergency department (ED) use among children involved with child protective services (CPS) in the U.S. but who remain at home, and to determine if ED use is related to child, caregiver and family characteristics as well as receipt of CPS services. Method We analyzed data on 4,001 children in the National Survey of Child and Adolescent Well-being. Multivariate models compared rates of ED use for whether the family received CPS services or did not receive CPS services as well as child characteristics, caregiver characteristics and caregiver/family psychological variables. Results ED use among children who remained at home receiving CPS services was similar to that of children who did not receive CPS services (35.6% and 37.4%, respectively). In multivariate modeling, children with families who received CPS services, children six years or older, and children without a chronic health problem were less likely to use the ED. Children who remained at home in families identified with numerous stressors and, therefore, likely at high risk for future abuse and neglect were 1.73 times (95% CI, 1.14–2.63) more likely to have repeat ED use than children in low risk families. Conclusion Children who remain at home after a CPS evaluation are at high risk for ED use. Future research should focus on the health problems that precipitate an ED visit as well as the relationship between primary care and ED use. PMID:22265905

Creating personalised clinical pathways by semantic interoperability with electronic health records.

PubMed

Wang, Hua-Qiong; Li, Jing-Song; Zhang, Yi-Fan; Suzuki, Muneou; Araki, Kenji

2013-06-01

There is a growing realisation that clinical pathways (CPs) are vital for improving the treatment quality of healthcare organisations. However, treatment personalisation is one of the main challenges when implementing CPs, and the inadequate dynamic adaptability restricts the practicality of CPs. The purpose of this study is to improve the practicality of CPs using semantic interoperability between knowledge-based CPs and semantic electronic health records (EHRs). Simple protocol and resource description framework query language is used to gather patient information from semantic EHRs. The gathered patient information is entered into the CP ontology represented by web ontology language. Then, after reasoning over rules described by semantic web rule language in the Jena semantic framework, we adjust the standardised CPs to meet different patients' practical needs. A CP for acute appendicitis is used as an example to illustrate how to achieve CP customisation based on the semantic interoperability between knowledge-based CPs and semantic EHRs. A personalised care plan is generated by comprehensively analysing the patient's personal allergy history and past medical history, which are stored in semantic EHRs. Additionally, by monitoring the patient's clinical information, an exception is recorded and handled during CP execution. According to execution results of the actual example, the solutions we present are shown to be technically feasible. This study contributes towards improving the clinical personalised practicality of standardised CPs. In addition, this study establishes the foundation for future work on the research and development of an independent CP system. Copyright © 2013 Elsevier B.V. All rights reserved.

An Open Metadata Schema for Clinical Pathway (openCP) in China.

PubMed

Xu, Wei; Zhu, Yanxin; Wang, Xia

2017-01-01

China has issued and implemented standard clinical pathways (Chinese standard CPs) since 2009; however, they are still paper-based CPs. The aim of the study is to reorganize Chinese standard CPs based on related Chinese medical standards, by using archetype approach, and develop an Open platform for CP (openCP) in China.

45. C.P.S., photographer January 1936 MENDOCINO COUNTY, SECTION, HIGHWAY 1. ...

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

45. C.P.S., photographer January 1936 MENDOCINO COUNTY, SECTION, HIGHWAY 1. MEN-I-J #132, 388+00 81TTC2, LOOKING SOUTH LANES FLAT, C.P.S., 1-36. - Redwood National & State Parks Roads, California coast from Crescent City to Trinidad, Crescent City, Del Norte County, CA

Effect of worker contacts on risk of child maltreatment recurrence among CPS-involved children and families.

PubMed

Halverson, Julie L; Russell, Jesse Rio; Kerwin, Colleen

2018-06-05

The mission and responsibility of child protective services (CPS) is to investigate maltreatment; intervene to protect children from harm; and promote safety, permanency, and well-being (DePanfilis & Salus, 2003; Goldman, Salus, Wolcott, & Kennedy, 2003). In 2015, approximately 7.2 million children in the United States were referred to CPS agencies, and 3.4 million children had an investigation or received an alternative response (US Department of Health & Human Services, 2017). Fluke, Shusterman, Hollinshead, and Yuan (2005) found that about one third of children with an allegation of maltreatment would have at least one re-report within a five-year period. Research indicates that the rates of child maltreatment or changes in indicators of child maltreatment have remained unchanged over time (Gilbert et al., 2012). Despite policies aimed at reducing or preventing maltreatment, the development of CPS systems across the United States, and a CPS workforce, the aggregate effects of the CPS system, services, and worker efforts are not well understood. Copyright © 2018 Elsevier Ltd. All rights reserved.

MnO2-GO double-shelled sulfur (S@MnO2@GO) as a cathode for Li-S batteries with improved rate capability and cyclic performance

NASA Astrophysics Data System (ADS)

Huang, Xingkang; Shi, Keying; Yang, Joseph; Mao, George; Chen, Junhong

2017-07-01

Sulfur cathodes have attracted much attention recently because of their high energy density and power density. However, sulfur possesses very poor electrical conductivity, and lithium polysulfides, resulting from the lithiation of sulfur, are prone to dissolving into electrolytes, which leads to the loss of active materials and poor cyclic performance of the sulfur cathodes. Here we report an MnO2-graphene oxide (GO) double-shelled sulfur (S@MnO2@GO) with improved rate capability and cyclic performance, in which we propose a new reaction using sulfur-reducing KMnO4 to produce MnO2 that covers the surface of the excess sulfur in situ. The resulting MnO2 with honeycomb-like morphology provides excellent voids for storing polysulfides. The outermost GO was assembled to block the open pores of MnO2, thereby minimizing the opportunity for polysulfides to leach into the electrolytes. The GO significantly improved the electrical conductivity of the sulfur cathode, and the S@MnO2@GO exhibited excellent rate capability and long cycle life.

Preventing the dissolution of lithium polysulfides in lithium-sulfur cells by using Nafion-coated cathodes.

PubMed

Oh, Soo Jung; Lee, Jun Kyu; Yoon, Woo Young

2014-09-01

The principal drawback of lithium-sulfur batteries is the dissolution of long-chain lithium polysulfides into the electrolyte, which limits cycling performance. To overcome this problem, we focused on the development of a novel cathode as well as anode material and designed Nafion-coated NiCrAl/S as a cathode and lithium powder as an anode. Nafion-coated NiCrAl/S cathode was synthesized using a two-step dip-coating technique. The lithium-powder anode was used instead of a lithium-foil anode to prohibit dendrite growth and to improve on the electrochemical behaviors. The cells showed an initial discharge capacity of about 900 mA g(-1) and a final discharge capacity of 772 mA g(-1) after 100 cycles at 0.1 C-rate. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) demonstrate that using the Nafion-coated NiCrAl/S cathode can suppress the dissolution of long-chain lithium polysulfides. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A F-doped tree-like nanofiber structural poly-m-phenyleneisophthalamide separator for high-performance lithium-sulfur batteries

NASA Astrophysics Data System (ADS)

Deng, Nanping; Wang, Yan; Yan, Jing; Ju, Jingge; Li, Zongjie; Fan, Lanlan; Zhao, Huijuan; Kang, Weimin; Cheng, Bowen

2017-09-01

In this study, F-doped tree-like nanofiber structural poly-m-phenyleneisophthalamide (PMIA) membranes are prepared via one-step electrospinning approach and their application performance as separators for lithium-sulfur batteries are discussed. The F-doped PMIA membrane can be regarded as matrix to form gel polymer electrolyte. The F doping endows the PMIA membranes with extraordinary high electrolyte uptake, excellent ability of preserving the liquid electrolyte and forceful chemisorption to polysulfides. And the tree-like structure effectively blocks polysulfides by the physical confinement. The lithium-sulfur cell with the F-doped PMIA separator exhibits high first-cycle discharge capacity of 1222.5 mAh g-1 and excellent cycling stability with good capacity retention of 745.7 mAh g-1 and coulombic efficiency of 97.97% after 800 cycles. The remarkable performance can be ascribed to the suppressed shuttle effects through both the physical trapping of polysulfides by the gel polymer electrolyte based on matrix with F-doped PMIA membrane and the tree-like structure in a working cell.

Improvement of Energy Capacity with Vitamin C Treated Dual-Layered Graphene-Sulfur Cathodes in Lithium-Sulfur Batteries.

PubMed

Kim, Jin Won; Ocon, Joey D; Kim, Ho-Sung; Lee, Jaeyoung

2015-09-07

A graphene-based cathode design for lithium-sulfur batteries (LSB) that shows excellent electrochemical performance is proposed. The dual-layered cathode is composed of a sulfur active layer and a polysulfide absorption layer, and both layers are based on vitamin C treated graphene oxide at various degrees of reduction. By controlling the degree of reduction of graphene, the dual-layered cathode can increase sulfur utilization dramatically owing to the uniform formation of nanosized sulfur particles, the chemical bonding of dissolved polysulfides on the oxygen-rich sulfur active layer, and the physisorption of free polysulfides on the absorption layer. This approach enables a LSB with a high specific capacity of over 600 mAh gsulfur (-1) after 100 cycles even under a high current rate of 1C (1675 mA gsulfur (-1) ). An intriguing aspect of our work is the synthesis of a high-performance dual-layered cathode by a green chemistry method, which could be a promising approach to LSBs with high energy and power densities. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Boiling enriches the linear polysulfides and the hydrogen sulfide-releasing activity of garlic.

PubMed

Tocmo, Restituto; Wu, Yuchen; Liang, Dong; Fogliano, Vincenzo; Huang, Dejian

2017-04-15

Garlic is rich in polysulfides, and some of them can be H 2 S donors. This study was conducted to explore the effect of cooking on garlic's organopolysulfides and H 2 S-releasing activity. Garlic bulbs were crushed and boiled for a period ranging from 3 to 30min and the solvent extracts were analyzed by GC-MS/FID and HPLC. A cell-based assay was used to measure the H 2 S-releasing activity of the extracts. Results showed that the amounts of allyl polysulfides increased in crushed garlic boiled for 6-10min; however, prolonging the thermal treatment to 20 or 30min decreased their concentrations. Data of the H 2 S-releasing activity, expressed as diallyl trisulfide equivalents (DATS-E), parallel this trend, being significantly higher at 6 and 10min boiling. Our results showed enhancement of H 2 S-releasing activity upon moderate boiling, suggesting that shorter cooking time may maximize its health benefits as a dietary source of natural H 2 S donors. Copyright © 2016 Elsevier Ltd. All rights reserved.

The mechanism of Li2S activation in lithium-sulfur batteries: Can we avoid the polysulfide formation?

NASA Astrophysics Data System (ADS)

Vizintin, Alen; Chabanne, Laurent; Tchernychova, Elena; Arčon, Iztok; Stievano, Lorenzo; Aquilanti, Giuliana; Antonietti, Markus; Fellinger, Tim-Patrick; Dominko, Robert

2017-03-01

Electrochemical reactions in the Lisbnd S batteries are considered as a multistep reaction process with at least 2-3 equilibrium states. Here we report a possibility of having a conversion of Li2S into sulfur without detectible formation of polysulfides. That was confirmed by using a novel material system consisting of carbon coated Li2S particles prepared by carbothermal reduction of Li2SO4. Two independent in operando measurements showed direct oxidation of Li2S into sulfur for this system, with almost negligible formation of polysulfides at potentials above 2.5 V vs. Li/Li+. Our results link the diversity of first charge profiles in the literature to the Li2S oxidation mechanism and show the importance of ionic wiring within the material. Furthermore, we demonstrate that the Li2S oxidation mechanism depends on the relative amount of soluble sulfur in the electrolyte. By controlling the type and the amount of electrolyte within the encapsulating carbon shell, it is thereby possible to control the reaction mechanism of Li2S activation.

Performance Enhancement of a Sulfur/Carbon Cathode by Polydopamine as an Efficient Shell for High-Performance Lithium-Sulfur Batteries.

PubMed

Zhang, Xuqing; Xie, Dong; Zhong, Yu; Wang, Donghuang; Wu, Jianbo; Wang, Xiuli; Xia, Xinhui; Gu, Changdong; Tu, Jiangping

2017-08-04

Lithium-sulfur batteries (LSBs) are considered to be among the most promising next-generation high-energy batteries. It is a consensus that improving the conductivity of sulfur cathodes and impeding the dissolution of lithium polysulfides are two key accesses to high-performance LSBs. Herein we report a sulfur/carbon black (S/C) cathode modified by self-polymerized polydopamine (pDA) with the assistance of polymerization treatment. The pDA acts as a novel and effective shell on the S/C cathode to stop the shuttle effect of polysulfides. By the synergistic effect of enhanced conductivity and multiple blocking effect for polysulfides, the S/C@pDA electrode exhibits improved electrochemical performances including large specific capacity (1135 mAh g -1 at 0.2 C), high rate capability (533 mAh g -1 at 5 C) and long cyclic life (965 mAh g -1 after 200 cycles). Our smart design strategy may promote the development of high-performance LSBs. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Positioning navigation and timing service applications in cyber physical systems

NASA Astrophysics Data System (ADS)

Qu, Yi; Wu, Xiaojing; Zeng, Lingchuan

2017-10-01

The positioning navigation and timing (PNT) architecture was discussed in detail, whose history, evolvement, current status and future plan were presented, main technologies were listed, advantages and limitations of most technologies were compared, novel approaches were introduced, and future capacities were sketched. The concept of cyber-physical system (CPS) was described and their primary features were interpreted. Then the three-layer architecture of CPS was illustrated. Next CPS requirements on PNT services were analyzed, including requirements on position reference and time reference, requirements on temporal-spatial error monitor, requirements on dynamic services, real-time services, autonomous services, security services and standard services. Finally challenges faced by PNT applications in CPS were concluded. The conclusion was expected to facilitate PNT applications in CPS, and furthermore to provide references to the design and implementation of both architectures.

Concurrent partnerships in Cape Town, South Africa: race and sex differences in prevalence and duration of overlap

PubMed Central

Beauclair, Roxanne; Hens, Niel; Delva, Wim

2015-01-01

Introduction Concurrent partnerships (CPs) have been suggested as a risk factor for transmitting HIV, but their impact on the epidemic depends upon how prevalent they are in populations, the average number of CPs an individual has and the length of time they overlap. However, estimates of prevalence of CPs in Southern Africa vary widely, and the duration of overlap in these relationships is poorly documented. We aim to characterize concurrency in a more accurate and complete manner, using data from three disadvantaged communities of Cape Town, South Africa. Methods We conducted a sexual behaviour survey (n=878) from June 2011 to February 2012 in Cape Town, using Audio Computer-Assisted Self-Interviewing to collect sexual relationship histories on partners in the past year. Using the beginning and end dates for the partnerships, we calculated the point prevalence, the cumulative prevalence and the incidence rate of CPs, as well as the duration of overlap for relationships begun in the previous year. Linear and binomial regression models were used to quantify race (black vs. coloured) and sex differences in the duration of overlap and relative risk of having CPs in the past year. Results The overall point prevalence of CPs six months before the survey was 8.4%: 13.4% for black men, 1.9% for coloured men, 7.8% black women and 5.6% for coloured women. The median duration of overlap in CPs was 7.5 weeks. Women had less risk of CPs in the previous year than men (RR 0.43; 95% CI: 0.32–0.57) and black participants were more at risk than coloured participants (RR 1.86; 95% CI: 1.17–2.97). Conclusions Our results indicate that in this population the prevalence of CPs is relatively high and is characterized by overlaps of long duration, implying there may be opportunities for HIV to be transmitted to concurrent partners. PMID:25697328

Efficacy of lacosamide by focal seizure subtype.

PubMed

Sperling, Michael R; Rosenow, Felix; Faught, Edward; Hebert, David; Doty, Pamela; Isojärvi, Jouko

2014-10-01

The purpose of this post hoc exploratory analysis was to determine the effects of the antiepileptic drug, lacosamide, on focal (partial-onset) seizure subtypes. Patient data from the three lacosamide pivotal trials were grouped and pooled by focal seizure subtype at Baseline: simple partial seizures (SPS), complex partial seizures (CPS), and secondarily generalized partial seizures (SGPS). Both efficacy outcomes (median percent change from Baseline to Maintenance Phase in seizure frequency per 28 days and the proportion of patients experiencing at least a 50% reduction in seizures) were evaluated by lacosamide dose (200, 400, or 600 mg/day) compared to placebo for each seizure subtype. An additional analysis was performed to determine whether a shift from more severe focal seizure subtypes to less severe occurred upon treatment with lacosamide. In patients with CPS or SGPS at Baseline, lacosamide 400 mg/day (maximum recommended daily dose) and 600 mg/day reduced the frequency of CPS and SGPS compared to placebo. Likewise, a proportion of patients with CPS and SGPS at Baseline experienced at least a 50% reduction in the frequency of CPS and SGPS (≥50% responder rate) in the lacosamide 400 and 600 mg/day groups compared with placebo. For both outcomes, numerically greatest responses were observed in the lacosamide 600 mg/day group among patients with SGPS at Baseline. In patients with SPS at Baseline, no difference between placebo and lacosamide was observed for either efficacy outcome. An additional exploratory analysis suggests that in patients with SPS at Baseline, CPS and SGPS may have been shifted to less severe SPS upon treatment with lacosamide. The results of these exploratory analyses revealed reductions in CPS and SGPS frequency with adjunctive lacosamide. Reduction in CPS and SGPS may confound assessment of SPS since the CPS or SGPS may possibly change to SPS by effective treatment. Copyright © 2014 Elsevier B.V. All rights reserved.

Binding of purified and radioiodinated capsular polysaccharides from Cryptococcus neoformans serotype A strains to capsule-free mutants.

PubMed Central

Small, J M; Mitchell, T G

1986-01-01

Strains 6, 15, 98, 110, and 145 of Cryptococcus neoformans serotype A vary in capsule size, animal virulence, and susceptibility to in vitro phagocytosis. The isolated capsular polysaccharides (CPSs) differ in monosaccharide composition ratios and molecular size, as determined by gel filtration. The purpose of this investigation was to characterize the binding of CPSs to capsule-free mutants of C. neoformans and to examine CPSs from these strains for differences in their ability to bind, to determine whether such differences might explain the variation in the pathobiology of these strains. CPSs were partially periodate oxidized, tyraminated, iodinated with 125I, and used in binding studies with two capsule-free mutants of C. neoformans, strain 602 and Cap59. Binding was specific for yeast species and for polysaccharide and was saturable, which is consistent with a receptor-mediated mechanism of attachment. Binding occurred rapidly and was only slowly reversible. Binding was also independent of pH from pH 5.5 to 8, of cation concentrations, and of competition by sugars up to 1.0 M concentrations. Only a portion of CPS was capable of binding, and strains varied in the extent to which their CPS bound. CPS-15-IV (peak IV was the major polysaccharide peak on DEAE-cellulose chromatography of CPS from strain 15) had the highest proportion of binding (40%), followed by CPS from strains 98, 6, 145, 110, and 15-III (peak III was an earlier eluting fraction of CPS from strain 15). The CPSs differed similarly in their ability to competitively inhibit binding. Treatment of CPS, but not yeast cells, with proteinase XIV abolished binding without altering the CPS gross structure. Treatment of yeast cells with proteases, heat, or formaldehyde did not alter binding, and both strain 602 and Cap59 bound CPS similarly. Binding to encapsulated yeast cells was minimal. PMID:3536747

Binding of purified and radioiodinated capsular polysaccharides from Cryptococcus neoformans serotype A strains to capsule-free mutants

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

Small, J.M.; Mitchell, T.G.

Strains 6, 15, 98, 110, and 145 of Cryptococcus neoformans serotype A vary in capsule size, animal virulence, and susceptibility to in vitro phagocytosis. The isolated capsular polysaccharides (CPSs) differ in monosaccharide composition ratios and molecular size, as determined by gel filtration. The purpose of this investigation was to characterize the binding of CPSs to capsule-free mutants of C. neoformans and to examine CPSs from these strains for differences in their ability to bind, to determine whether such differences might explain the variation in the pathobiology of these strains. CPSs were partially periodate oxidized, tyraminated, iodinated with /sup 125/I, andmore » used in binding studies with two capsule-free mutants of C. neoformans, strain 602 and Cap59. Binding was specific for yeast species and for polysaccharide and was saturable, which is consistent with a receptor-mediated mechanism of attachment. Binding occurred rapidly and was only slowly reversible. Binding was also independent of pH from pH 5.5 to 8, of cation concentrations, and of competition by sugars up to 1.0 M concentrations. Only a portion of CPS was capable of binding, and strains varied in the extent to which their CPS bound. CPS-15-IV (peak IV was the major polysaccharide peak on DEAE-cellulose chromatography of CPS from strain 15) had the highest proportion of binding (40%), followed by CPS from strains 98, 6, 145, 110, and 15-III (peak III was an earlier eluting fraction of CPS from strain 15). The CPSs differed similarly in their ability to competitively inhibit binding. Treatment of CPS, but not yeast cells, with proteinase XIV abolished binding without altering the CPS gross structure. Treatment of yeast cells with proteases, heat, or formaldehyde did not alter binding, and both strain 602 and Cap59 bound CPS similarly. Binding to encapsulated yeast cells was minimal.« less

Analysis of white box test of cyber-physical system

NASA Astrophysics Data System (ADS)

Li, Bo; Zhang, Lichen

2017-05-01

The Cyber-Physical System is a complex system in which the information system is closely integrated with the physical system. Through the environment detection and the combination of computing, communication and control process, the physical real-time perception and dynamic control function are realized. CPS is another information revolution after the Internet, and his presence will change the way people interact with the physical world. In this paper, the concept of CPS and white box testing is introduced, and then the white box test for CPS hardware, software, network and system is discussed in detail. Finally, the research on CPS is prospected.

Non-encapsidation Activities of the Capsid Proteins of Positive-strand RNA Viruses

PubMed Central

Ni, Peng; Kao, C. Cheng

2013-01-01

Viral capsid proteins (CPs) are characterized by their role in forming protective shells around viral genomes. However, CPs have additional and important roles in the virus infection cycles and in the cellular response to infection. These activities involve CP binding to RNAs in both sequence-specific and nonspecific manners as well as association with other proteins. This review focuses on CPs of both plant and animal-infecting viruses with positive-strand RNA genomes. We summarize the structural features of CPs and describe their modulatory roles in viral translation, RNA-dependent RNA synthesis, and host defense responses. PMID:24074574

Economic evaluations of clinical pharmacy services: 2006-2010.

PubMed

Touchette, Daniel R; Doloresco, Fred; Suda, Katie J; Perez, Alexandra; Turner, Stuart; Jalundhwala, Yash; Tangonan, Maria C; Hoffman, James M

2014-08-01

Studies have consistently evidenced the positive clinical, economic, and humanistic benefits of pharmacist-directed patient care in a variety of settings. Given the vast differences in clinical outcomes associated with evaluated clinical pharmacy services (CPS), more detail as to the nature of the CPS is needed to better understand observed differences in economic outcomes. With the growing trend of outpatient pharmacy services, these economic evaluations serve as viable decision-making tools in choosing the most effective and cost-effective pharmacy programs. We previously conducted three systematic reviews to evaluate the economic impact of CPS from 1988 to 2005. In this systematic review, our objectives were to describe and evaluate the quality of economic evaluations of CPS published between 2006 and 2010, with the goal of informing administrators and practitioners as to their cost-effectiveness. We searched the scientific literature by using the Medline, International Pharmaceutical Abstracts, Embase, and Cumulative Index to Nursing and Allied Health Literature databases to identify studies describing CPS published from 2006 to 2010. Studies meeting our inclusion criteria (original research articles that evaluated CPS and described economic and clinical outcomes) were reviewed by two investigators. Methodology used, economic evaluation type, CPS setting and type, and clinical and economic outcome results were extracted. Results were informally compared with previous systematic reviews. Of 3587 potential studies identified, 25 met inclusion criteria. Common CPS settings were hospital (36%), community (32%), and clinic or hospital-based ambulatory practices (28%). CPS types were disease state management (48%), general pharmacotherapeutic monitoring (24%), target drug programs (8%), and patient education (4%). Two studies (8%) listed CPS as medication therapy management. Costs were evaluated in 24 studies (96%) and sufficiently described in 13 (52%). Clinical or humanistic outcomes were evaluated in 20 studies (80%) and were sufficiently described in 18 (72%). Control groups were included in 16 (70%) of 23 studies not involving modeling. Study assumptions and limitations were stated and justified in eight studies (32%). Conclusions and recommendations were considered justified and based on results in 24 studies (96%). Eighteen studies (72%) involved full economic evaluation. The mean ± SD study quality score for full economic evaluations (18 studies) was 60.4 ± 22.3 of a possible 100 points. Benefit-cost ratios from three studies ranged from 1.05:1 to 25.95:1, and incremental cost-effectiveness ratios of five studies were calculated and reported. Fewer studies documented the economic impact of CPS from 2006-2010 than from 2001-2005, although a higher proportion involved controlled designs and were full economic evaluations. Evaluations of ambulatory practices were increasingly common. CPS were generally considered cost-effective or provided a good benefit-cost ratio. © 2014 Pharmacotherapy Publications, Inc.

Development of a 3D cell printed structure as an alternative to autologs cartilage for auricular reconstruction.

PubMed

Park, Ju Young; Choi, Yeong-Jin; Shim, Jin-Hyung; Park, Jeong Hun; Cho, Dong-Woo

2017-07-01

Surgical technique using autologs cartilage is considered as the best treatment for cartilage tissue reconstruction, although the burdens of donor site morbidity and surgical complications still remain. The purpose of this study is to apply three-dimensional (3D) cell printing to fabricate a tissue-engineered graft, and evaluate its effects on cartilage reconstruction. A multihead tissue/organ building system is used to print cell-printed scaffold (CPS), then assessed the effect of the CPS on cartilage regeneration in a rabbit ear. The cell viability and functionality of chondrocytes were significantly higher in CPS than in cell-seeded scaffold (CSS) and cell-seeded hybrid scaffold (CSHS) in vitro. CPS was then implanted into a rabbit ear that had an 8 mm-diameter cartilage defect; at 3 months after implantation the CPS had fostered complete cartilage regeneration whereas CSS and autologs cartilage (AC) fostered only incomplete healing. This result demonstrates that cell printing technology can provide an appropriate environment in which encapsulated chondrocytes can survive and differentiate into cartilage tissue in vivo. Moreover, the effects of CPS on cartilage regeneration were even better than those of AC. Therefore, we confirmed the feasibility of CPS as an alternative to AC for auricular reconstruction. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1016-1028, 2017. © 2016 Wiley Periodicals, Inc.

Consumer providers' experiences of recovery and concerns as members of a psychiatric multidisciplinary outreach team: A qualitative descriptive study from the Japan Outreach Model Project 2011-2014.

PubMed

Kido, Yoshifumi; Kayama, Mami

2017-01-01

The objective of this study was to clarify consumer providers (CPs) subjective experiences as members of a psychiatric multidisciplinary outreach team that provided services to individuals with a mental illness living in the community. A qualitative descriptive study was conducted through semi-structured interviews. Participants were clients hired as CPs in the Japanese Outreach Model Project from September 2011 until March 2014. Of the seventeen CPs, nine participated in this study. We looked at the CPs' subjective experiences of fulfillment and difficulty. In the process of providing services, CPs experienced both achievements and concerns. They had a sense of achievement by caring for their clients and they experienced that they themselves were recovering. They were also concerned about having inadequate knowledge and skills to provide psychiatric services to their clients. Further, there were concerns about their dual role on the multidisciplinary team and being support staff while they were still using mental health services themselves. The results show that the activities of CPs included fulfillment, recovery, and dilemmas. Clarifications will likely contribute to an increase in understanding and cooperation between CPs and other professionals with whom they work. Further studies are needed to investigate policies related to mental health consumers who are also providers of mental health services.

Network Location-Aware Service Recommendation with Random Walk in Cyber-Physical Systems

PubMed Central

Yin, Yuyu; Yu, Fangzheng; Xu, Yueshen; Yu, Lifeng; Mu, Jinglong

2017-01-01

Cyber-physical systems (CPS) have received much attention from both academia and industry. An increasing number of functions in CPS are provided in the way of services, which gives rise to an urgent task, that is, how to recommend the suitable services in a huge number of available services in CPS. In traditional service recommendation, collaborative filtering (CF) has been studied in academia, and used in industry. However, there exist several defects that limit the application of CF-based methods in CPS. One is that under the case of high data sparsity, CF-based methods are likely to generate inaccurate prediction results. In this paper, we discover that mining the potential similarity relations among users or services in CPS is really helpful to improve the prediction accuracy. Besides, most of traditional CF-based methods are only capable of using the service invocation records, but ignore the context information, such as network location, which is a typical context in CPS. In this paper, we propose a novel service recommendation method for CPS, which utilizes network location as context information and contains three prediction models using random walking. We conduct sufficient experiments on two real-world datasets, and the results demonstrate the effectiveness of our proposed methods and verify that the network location is indeed useful in QoS prediction. PMID:28885602

Screening of Chlorinated Paraffins and Unsaturated Analogues in Commercial Mixtures: Confirmation of Their Occurrences in the Atmosphere.

PubMed

Li, Tong; Gao, Shixiong; Ben, Yujie; Zhang, Hong; Kang, Qiyue; Wan, Yi

2018-02-20

Characterizing the detailed compositions of chlorinated paraffins (CPs) commercial mixtures is crucial to understand their environmental sources, fates, and potential risks. In this study, dichloromethane (DCM)-enhanced UPLC-ESI-QTOFMS analysis combined with characteristic isotope chlorine peaks is applied to screen all CPs and their structural analogues in the three most commonly produced CP commercial mixtures (CP-42, CP-52, and CP-70). Mass fractions of total short-chain CPs (SCCPs), medium-chain CPs (MCCPs) and long-chain CPs (LCCPs) ranged from 0.64 to 31.9%, 0.64 to 21.8%, and 0.04 to 43.9%, respectively, in the three commercial mixtures. 113 unsaturated SCCPs, MCCPs, and LCCPs were identified in the commercial mixtures. The detailed mass percentages of saturated and unsaturated CPs with carbon numbers of 10-30, chlorine numbers of 5-28, and unsaturated degrees of 0-7 were characterized in all commercial mixtures. Occurrences of the predominant saturated and unsaturated CPs were further confirmed in air samples collected in Guangdong Province, one of the major CP production areas in China, over one year. The profiles of the detected compounds indicated that LCCPs in air samples might come mainly from the production and usage of CP-52, and unsaturated C 24-29 -LCCPs were specifically originated from CP-70 used in the area.

Patent medicine vendors, community pharmacists and STI management in Abuja, Nigeria.

PubMed

Okonkwo, A D; Okonkwo, U P

2010-09-01

Increasingly, literature indicates that Patent Medicine Vendors (PMVs) and Community Pharmacists (CPs) provide sexual reproductive health services and products to their young patrons. This study explored the validity of literature claims, principally from CPs and PMVs perspective in Abuja, Nigeria. Participants were recruited with convenience sampling based on their willingness to participate in the study and our judgement of their professional competence. They were administered a semi-structured questionnaire, which was modelled after McCracken's long interview. We empirically assessed the validity of CPs and PMVs opinions with an exit interview of seven consenting patrons. Interviews were audio taped, transcribed verbatim and subjected to iterative thematic analysis. Participants' accounts and our observations indicate that PMVs and CPs serve young people's sexual reproductive healthcare needs in Abuja. CPs and PMVs provide young people with a seamless and non-judgemental access to contraceptives, sexual health advice and post-sexual risk exposure care. The study corroborates literature claims that CPs and PMVs provide sexual reproductive health advice, services and products to young people. However, participants contend that the current pharmacy practice laws in Nigeria constrain the scope and quality of services that young unmarried people require. Because it is unlikely that Nigeria will reinvigorate her primary healthcare system soon, we call for the formal co-option of CPs and PMVs into the sexual reproductive health management system to standardize and improve services.

Aligator: A computational tool for optimizing total chemical synthesis of large proteins.

PubMed

Jacobsen, Michael T; Erickson, Patrick W; Kay, Michael S

2017-09-15

The scope of chemical protein synthesis (CPS) continues to expand, driven primarily by advances in chemical ligation tools (e.g., reversible solubilizing groups and novel ligation chemistries). However, the design of an optimal synthesis route can be an arduous and fickle task due to the large number of theoretically possible, and in many cases problematic, synthetic strategies. In this perspective, we highlight recent CPS tool advances and then introduce a new and easy-to-use program, Aligator (Automated Ligator), for analyzing and designing the most efficient strategies for constructing large targets using CPS. As a model set, we selected the E. coli ribosomal proteins and associated factors for computational analysis. Aligator systematically scores and ranks all feasible synthetic strategies for a particular CPS target. The Aligator script methodically evaluates potential peptide segments for a target using a scoring function that includes solubility, ligation site quality, segment lengths, and number of ligations to provide a ranked list of potential synthetic strategies. We demonstrate the utility of Aligator by analyzing three recent CPS projects from our lab: TNFα (157 aa), GroES (97 aa), and DapA (312 aa). As the limits of CPS are extended, we expect that computational tools will play an increasingly important role in the efficient execution of ambitious CPS projects such as production of a mirror-image ribosome. Copyright © 2017 Elsevier Ltd. All rights reserved.

Progress in lithium-sulfur batteries: the effective role of a polysulfide-added electrolyte as buffer to prevent cathode dissolution.

PubMed

Lee, Dong-Ju; Agostini, Marco; Park, Ju-Won; Sun, Yang-Kook; Hassoun, Jusef; Scrosati, Bruno

2013-12-01

Paving the road for sulfur: A unique electrolyte composition designed for the development of stable lithium-sulfur batteries with high energy. A battery with a high and stable capacity is prepared by using an electrolyte containing a dissolved catholyte-type compound, that is, Li2 S8 polysulfide. The cell is characterized by a capacity approaching the theoretical value at a working voltage of 2.1 V, which is remarkable compared to conventional lithium ion batteries. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Crystal growth of sulfide materials from alkali polysulfide liquids

NASA Technical Reports Server (NTRS)

White, W. B.

1979-01-01

The fluids experiment system was designed for low temperature solution growth, nominally aqueous solution growth. The alkali polysulfides, compositions in the systems Na2S-S and K2S-S form liquids in the temperature range of 190 C to 400 C. These can be used as solvents for other important classes of materials such as transition metal and other sulfides which are not soluble in aqueous media. Among these materials are luminescent and electroluminescent crystals whose physical properties are sensitive functions of crystal perfection and which could, therefore, serve as test materials for perfection improvement under microgravity conditions.

Stability of the Solid Electrolyte Interface on the Li Electrode in Li–S Batteries

DOE PAGES

Zheng, Dong; Yang, Xiao-Qing; Qu, Deyang

2016-04-05

In this study, by means of high performance liquid chromatography–mass spectroscopy, the concentration of sulfur and polysulfides was determined in nonaqueous electrolytes. The stability of sulfur and Li in eight electrolytes was studied quantitatively. It was found that sulfur reacted with Li in most of the commonly used electrolytes for lithium–sulfur batteries. The reaction products between sulfur and Li were qualitatively identified. In some cases, the solid electrolyte interface on the Li can successfully prevent the interaction between S and Li; however, it was found that the solid electrolyte interface was damaged by polysulfide ions.

Teacher Hiring, Transfer and Assignment in Chicago Public Schools. Executive Summary

ERIC Educational Resources Information Center

New Teacher Project, 2007

2007-01-01

In the winter of 2006-2007, The New Teacher Project (TNTP) engaged in an extensive review of teacher staffing policies and practices in Chicago Public Schools (CPS). TNTP investigated the impact of CPS staffing rules through several avenues: (1) Review of CPS Teachers contract; (2) Analysis of Human Resources transaction data; (3) Surveys of…

Complex Problem Solving in Educational Contexts--Something beyond "g": Concept, Assessment, Measurement Invariance, and Construct Validity

ERIC Educational Resources Information Center

Greiff, Samuel; Wustenberg, Sascha; Molnar, Gyongyver; Fischer, Andreas; Funke, Joachim; Csapo, Beno

2013-01-01

Innovative assessments of cross-curricular competencies such as complex problem solving (CPS) have currently received considerable attention in large-scale educational studies. This study investigated the nature of CPS by applying a state-of-the-art approach to assess CPS in high school. We analyzed whether two processes derived from cognitive…

Agent-Based Modeling of Collaborative Problem Solving. Research Report. ETS RR-16-27

ERIC Educational Resources Information Center

Bergner, Yoav; Andrews, Jessica J.; Zhu, Mengxiao; Gonzales, Joseph E.

2016-01-01

Collaborative problem solving (CPS) is a critical competency in a variety of contexts, including the workplace, school, and home. However, only recently have assessment and curriculum reformers begun to focus to a greater extent on the acquisition and development of CPS skill. One of the major challenges in psychometric modeling of CPS is…

National CPS Certification | A Program of Safe Kids Worldwide

Science.gov Websites

the Tech! ABOUT THE PROGRAM National CPS Certification Training is a program of Safe Kids Worldwide ; E-Vouchers FAQS/HELP FAQs Fees Forms Policies & Procedures Who We Are NHTSA Safe Kids CPS-board State Farm Follow us on Facebook Copyright © 2017 by Safe Kids Worldwide - Child Passenger Safety

Role of superconducting energy gap in extended BCS-Bose crossover theory

NASA Astrophysics Data System (ADS)

Chávez, I.; García, L. A.; de Llano, M.; Grether, M.

2017-10-01

The generalized Bose-Einstein condensation (GBEC) theory of superconductivity (SC) is briefly surveyed. It hinges on three distinct new ingredients: (i) Treatment of Cooper pairs (CPs) as actual bosons since they obey Bose statistics, in contrast to BCS pairs which do not obey Bose commutation relations; (ii) inclusion of two-hole Cooper pairs (2hCPs) on an equal footing with two-electron Cooper pairs (2eCPs), thus making this a complete boson-fermion (BF) model; and (iii) inclusion in the resulting ternary ideal BF gas with particular BF vertex interactions that drive boson formation/disintegration processes. GBEC subsumes as special cases both BCS (having its 50-50 symmetry of both kinds of CPs) and ordinary BEC theories (having no 2hCPs), as well as the now familiar BCS-Bose crossover theory. We extended the crossover theory with the explicit inclusion of 2hCPs and construct a phase diagram of Tc/TF versus n/nf, where Tc and TF are the critical and Fermi temperatures, n is the total number density and nf that of unbound electrons at T = 0. Also, with this extended crossover one can construct the energy gap Δ(T)/Δ(0) versus T/Tc for some elemental SCs by solving at least two equations numerically: a gap-like and a number equation. In 50-50 symmetry, the energy gap curve agrees quite well with experimental data. But ignoring 2hCPs altogether leads to the gap curve falling substantially below that with 50-50 symmetry which already fits the data quite well, showing that 2hCPs are indispensable to describe SCs.

A cross-sectional evaluation of community pharmacists' perceptions of intermediate care and medicines management across the healthcare interface.

PubMed

Millar, Anna; Hughes, Carmel; Devlin, Maria; Ryan, Cristín

2016-12-01

Background Despite the importance placed on the concept of the multidisciplinary team in relation to intermediate care (IC), little is known about community pharmacists' (CPs) involvement. Objective To determine CPs' awareness of and involvement with IC services, perceptions of the transfer of patients' medication information between healthcare settings and views of the development of a CP-IC service. Setting Community pharmacies in Northern Ireland. Methods A postal questionnaire, informed by previous qualitative work was developed and piloted. Main outcome measure CPs' awareness of and involvement with IC. Results The response rate was 35.3 % (190/539). Under half (47.4 %) of CPs 'agreed/strongly agreed' that they understood the term 'intermediate care'. Three quarters of respondents were either not involved or unsure if they were involved with providing services to IC. A small minority (1.2 %) of CPs reported that they received communication regarding medication changes made in hospital or IC settings 'all of the time'. Only 9.5 and 0.5 % of respondents 'strongly agreed' that communication from hospital and IC, respectively, was sufficiently detailed. In total, 155 (81.6 %) CPs indicated that they would like to have greater involvement with IC services. 'Current workload' was ranked as the most important barrier to service development. Conclusion It was revealed that CPs had little awareness of, or involvement with, IC. Communication of information relating to patients' medicines between settings was perceived as insufficient, especially between IC and community pharmacy settings. CPs demonstrated willingness to be involved with IC and services aimed at bridging the communication gap between healthcare settings.

A qualitative assessment of a community pharmacy cognitive pharmaceutical services program, using a work system approach.

PubMed

Chui, Michelle A; Mott, David A; Maxwell, Leigh

2012-01-01

Although lack of time, trained personnel, and reimbursement have been identified as barriers to pharmacists providing cognitive pharmaceutical services (CPS) in community pharmacies, the underlying contributing factors of these barriers have not been explored. One approach to better understand barriers and facilitators to providing CPS is to use a work system approach to examine different components of a work system and how the components may impact care processes. The goals of this study were to identify and describe pharmacy work system characteristics that pharmacists identified and changed to provide CPS in a demonstration program. A qualitative approach was used for data collection. A purposive sample of 8 pharmacists at 6 community pharmacies participating in a demonstration program was selected to be interviewed. Each semistructured interview was audio recorded and transcribed, and the text was analyzed in a descriptive and interpretive manner by 3 analysts. Themes were identified in the text and aligned with 1 of 5 components of the Systems Engineering Initiative for Patient Safety (SEIPS) work system model (organization, tasks, tools/technology, people, and environment). A total of 21 themes were identified from the interviews, and 7 themes were identified across all 6 interviews. The organization component of the SEIPS model contained the most (n=10) themes. Numerous factors within a pharmacy work system appear important to enable pharmacists to provide CPS. Leadership and foresight by the organization to implement processes (communication, coordination, planning, etc.) to facilitate providing CPS was a key finding across the interviews. Expanding technician responsibilities was reported to be essential for successfully implementing CPS. To be successful in providing CPS, pharmacists must be cognizant of the different components of the pharmacy work system and how these components influence providing CPS. Copyright © 2012 Elsevier Inc. All rights reserved.

SLAE–CPS: Smart Lean Automation Engine Enabled by Cyber-Physical Systems Technologies

PubMed Central

Ma, Jing; Wang, Qiang; Zhao, Zhibiao

2017-01-01

In the context of Industry 4.0, the demand for the mass production of highly customized products will lead to complex products and an increasing demand for production system flexibility. Simply implementing lean production-based human-centered production or high automation to improve system flexibility is insufficient. Currently, lean automation (Jidoka) that utilizes cyber-physical systems (CPS) is considered a cost-efficient and effective approach for improving system flexibility under shrinking global economic conditions. Therefore, a smart lean automation engine enabled by CPS technologies (SLAE–CPS), which is based on an analysis of Jidoka functions and the smart capacity of CPS technologies, is proposed in this study to provide an integrated and standardized approach to design and implement a CPS-based smart Jidoka system. A set of comprehensive architecture and standardized key technologies should be presented to achieve the above-mentioned goal. Therefore, a distributed architecture that joins service-oriented architecture, agent, function block (FB), cloud, and Internet of things is proposed to support the flexible configuration, deployment, and performance of SLAE–CPS. Then, several standardized key techniques are proposed under this architecture. The first one is for converting heterogeneous physical data into uniform services for subsequent abnormality analysis and detection. The second one is a set of Jidoka scene rules, which is abstracted based on the analysis of the operator, machine, material, quality, and other factors in different time dimensions. These Jidoka rules can support executive FBs in performing different Jidoka functions. Finally, supported by the integrated and standardized approach of our proposed engine, a case study is conducted to verify the current research results. The proposed SLAE–CPS can serve as an important reference value for combining the benefits of innovative technology and proper methodology. PMID:28657577

Rural access to clinical pharmacy services.

PubMed

Patterson, Brandon J; Kaboli, Peter J; Tubbs, Traviss; Alexander, Bruce; Lund, Brian C

2014-01-01

To examine the impact of rural residence and primary care site on use of clinical pharmacy services (CPS) and to describe the use of clinical telepharmacy within the Veterans Health Administration (VHA) health care system. Using 2011 national VHA data, the frequency of patients with CPS encounters was compared across patient residence (urban or rural) and principal site of primary care (medical center, urban clinic, or rural clinic). The likelihood of CPS utilization was estimated with random effects logistic regression. Individual service types (e.g., anticoagulation clinics) and delivery modes (e.g., telehealth) were also examined. Of 3,040,635 patients, 711,348 (23.4%) received CPS. Service use varied by patient residence (urban: 24.9%; rural: 19.7%) and principal site of primary care (medical center: 25.9%; urban clinic: 22.5%; rural clinic: 17.6%). However, in adjusted analyses, urban-rural differences were explained primarily by primary care site and less so by patient residence. Similar findings were observed for individual CPS types. Telehealth encounters were common, accounting for nearly one-half of patients receiving CPS. Video telehealth was infrequent (<0.2%), but more common among patients of rural clinics than those receiving CPS at medical centers (odds ratio [OR] = 9.7; 95% CI 9.0-10.5). We identified a potential disparity between rural and urban patients' access to CPS, which was largely explained by greater reliance on community clinics for primary care than on medical centers. Future research is needed to determine if this disparity will be alleviated by emerging organizational changes, including expanding telehealth capacity and integrating pharmacists into primary care teams, and whether lessons learned at VHA translate to other settings.

Antibody Response Specific to the Capsular Polysaccharide Is Impaired in Streptococcus suis Serotype 2-Infected Animals

PubMed Central

Calzas, Cynthia; Lemire, Paul; Auray, Gael; Gerdts, Volker; Gottschalk, Marcelo

2014-01-01

Streptococcus suis serotype 2 is an extracellular encapsulated bacterium that causes severe septicemia and meningitis in swine and humans. Albeit crucial in the fight against encapsulated bacteria, the nature of the capsular polysaccharide (CPS)-specific antibody (Ab) response during S. suis type 2 infection is unknown. We compared for the first time the features of CPS-specific versus protein-specific Ab responses during experimental infections with live virulent S. suis type 2 in mice. The primary protein-specific Ab response was dominated by both type 1 and 2 IgG subclasses, whereas IgM titers were more modest. The secondary protein-specific Ab response showed all of the features of a memory response with faster kinetics and boosted the titers of all Ig isotypes. In contrast, the primary CPS-specific Ab response was either inexistent or had titers only slightly higher than those in noninfected animals and was essentially composed of IgM. A poor CPS-specific memory response was observed, with only a moderate boost in IgM titers and no IgG. Both protein- and CPS-specific Ab responses were Toll-like receptor 2 independent. By using S. suis type 2 strains of European or North American origin, the poor CPS-specific Ab response was demonstrated to be independent of the genotypic/phenotypic diversity of the strain within serotype 2. Finally, the CPS-specific Ab response was also impaired and lacked isotype switching in S. suis-infected pigs, the natural host of the bacterium. The better resistance of preinfected animals to reinfection with the same strain of S. suis type 2 might thus more likely be related to the development of a protein rather than CPS Ab response. PMID:25385801

The thoracic muscular system and its innervation in third instar Calliphora vicina Larvae. I. Muscles of the pro- and mesothorax and the pharyngeal complex.

PubMed

Hanslik, Ulrike; Schoofs, Andreas; Niederegger, Senta; Heinzel, Hans-Georg; Spiess, Roland

2010-08-01

An anatomical description is given by the muscles in the pro- and mesothorax, and those associated with the feeding apparatus (cephalopharyngeal skeleton, CPS) that participate in feeding behavior in third instar Calliphora larvae. The body wall muscles in the pro- and mesothoracic segments are organized in three layers: internal, intermedial, and external. The muscles were labeled with roman numerals according to the nomenclature in use for the abdominal segments. Muscles associated with the CPS are labeled according to their function. The prothorax bears five pairs of lateral symmetrically longitudinal segmental body wall muscles and lacks the transversal muscle group present in the mesothorax and abdominal segments. Additionally, four pairs of intersegmental muscles project from the prothorax to the second, fourth, and fifth segment. The mesothorax bears 15 pairs of segmental longitudinal and 18 pairs of transversal muscles. The accessory pharyngeal muscles span the CPS and the cuticle. Three pairs of protractors and retractors and two pairs of mouth hook accessors (MH(AC)) exist, which move the CPS relative to the body. The pharyngeal muscles are exclusively attached to the structures of the CPS. The mouth hook elevators and depressors, which mediate the hooks rotation are attached to the ventral arm of the CPS and project to a dorsal (elevators) or ventral (depressors) protuberance of the mouth hooks. The cibarial dilator muscles (CDM) span the dorsal arms of the CPS and the dorsal surface of the esophagus and mediate food ingestion. The labial retractors (LRs) lack antagonists and project from the ventral surface of the CPS to the unpaired labium. Contractions of these muscles open the mouth cavity. J. Morphol. 271:960-968, 2010. (c) 2010 Wiley-Liss, Inc.

SLAE-CPS: Smart Lean Automation Engine Enabled by Cyber-Physical Systems Technologies.

PubMed

Ma, Jing; Wang, Qiang; Zhao, Zhibiao

2017-06-28

In the context of Industry 4.0, the demand for the mass production of highly customized products will lead to complex products and an increasing demand for production system flexibility. Simply implementing lean production-based human-centered production or high automation to improve system flexibility is insufficient. Currently, lean automation (Jidoka) that utilizes cyber-physical systems (CPS) is considered a cost-efficient and effective approach for improving system flexibility under shrinking global economic conditions. Therefore, a smart lean automation engine enabled by CPS technologies (SLAE-CPS), which is based on an analysis of Jidoka functions and the smart capacity of CPS technologies, is proposed in this study to provide an integrated and standardized approach to design and implement a CPS-based smart Jidoka system. A set of comprehensive architecture and standardized key technologies should be presented to achieve the above-mentioned goal. Therefore, a distributed architecture that joins service-oriented architecture, agent, function block (FB), cloud, and Internet of things is proposed to support the flexible configuration, deployment, and performance of SLAE-CPS. Then, several standardized key techniques are proposed under this architecture. The first one is for converting heterogeneous physical data into uniform services for subsequent abnormality analysis and detection. The second one is a set of Jidoka scene rules, which is abstracted based on the analysis of the operator, machine, material, quality, and other factors in different time dimensions. These Jidoka rules can support executive FBs in performing different Jidoka functions. Finally, supported by the integrated and standardized approach of our proposed engine, a case study is conducted to verify the current research results. The proposed SLAE-CPS can serve as an important reference value for combining the benefits of innovative technology and proper methodology.

A comparison of alternative methods for measuring cigarette prices.

PubMed

Chaloupka, Frank J; Tauras, John A; Strasser, Julia H; Willis, Gordon; Gibson, James T; Hartman, Anne M

2015-05-01

Government agencies, public health organisations and tobacco control researchers rely on accurate estimates of cigarette prices for a variety of purposes. Since the 1950s, the Tax Burden on Tobacco (TBOT) has served as the most widely used source of this price data despite its limitations. This paper compares the prices and collection methods of the TBOT retail-based data and the 2003 and 2006/2007 waves of the population-based Tobacco Use Supplement to the Current Population Survey (TUS-CPS). From the TUS-CPS, we constructed multiple state-level measures of cigarette prices, including weighted average prices per pack (based on average prices for single-pack purchases and average prices for carton purchases) and compared these with the weighted average price data reported in the TBOT. We also constructed several measures of tax avoidance from the TUS-CPS self-reported data. For the 2003 wave, the average TUS-CPS price was 71 cents per pack less than the average TBOT price; for the 2006/2007 wave, the difference was 47 cents. TUS-CPS and TBOT prices were also significantly different at the state level. However, these differences varied widely by state due to tax avoidance opportunities, such as cross-border purchasing. The TUS-CPS can be used to construct valid measures of cigarette prices. Unlike the TBOT, the TUS-CPS captures the effect of price-reducing marketing strategies, as well as tax avoidance practices and non-traditional types of purchasing. Thus, self-reported data like TUS-CPS appear to have advantages over TBOT in estimating the 'real' price that smokers face. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

A qualitative assessment of a community pharmacy cognitive pharmaceutical services program, using a work system approach

PubMed Central

Chui, Michelle A.; Mott, David A.; Maxwell, Leigh

2012-01-01

Background Although lack of time, trained personnel, and reimbursement have been identified as barriers to pharmacists providing cognitive pharmaceutical services (CPS) in community pharmacies, the underlying contributing factors of these barriers have not been explored. One approach to better understand barriers and facilitators to providing CPS is to use a work system approach to examine different components of a work system and how the components may impact care processes. Objectives The goals of this study were to identify and describe pharmacy work system characteristics that pharmacists identified and changed to provide CPS in a demonstration program. Methods A qualitative approach was used for data collection. A purposive sample of 8 pharmacists at 6 community pharmacies participating in a demonstration program was selected to be interviewed. Each semistructured interview was audio recorded and transcribed, and the text was analyzed in a descriptive and interpretive manner by 3 analysts. Themes were identified in the text and aligned with 1 of 5 components of the Systems Engineering Initiative for Patient Safety (SEIPS) work system model (organization, tasks, tools/technology, people, and environment). Results A total of 21 themes were identified from the interviews, and 7 themes were identified across all 6 interviews. The organization component of the SEIPS model contained the most (n = 10) themes. Numerous factors within a pharmacy work system appear important to enable pharmacists to provide CPS. Leadership and foresight by the organization to implement processes (communication, coordination, planning, etc.) to facilitate providing CPS was a key finding across the interviews. Expanding technician responsibilities was reported to be essential for successfully implementing CPS. Conclusions To be successful in providing CPS, pharmacists must be cognizant of the different components of the pharmacy work system and how these components influence providing CPS. PMID:21824822

Cost-effectiveness evaluation of clobetasol propionate shampoo (CPS) maintenance in patients with moderate scalp psoriasis: a Pan-European analysis.

PubMed

Papp, K; Poulin, Y; Barber, K; Lynde, C; Prinz, J C; Berg, M; Kerrouche, N; Rives, V P

2012-11-01

Scalp psoriasis is a difficult to treat and usually chronic manifestation of psoriasis. The CalePso study showed that CPS (Clobex(®) Shampoo) in maintenance therapy of scalp psoriasis (twice weekly) significantly increases the probability of keeping patient under remission during 6 months, compared with vehicle (40.3% relapses vs. 11.6% relapses, ITT). The objective of the study was to assess the cost-effectiveness of a maintenance therapy with CPS vs. its vehicle in nine European countries. A 24-week decision tree model was developed with 4-weekly time steps. The considered population has moderate scalp psoriasis successfully treated with a daily application of CPS up to 4 weeks. Data were taken from the CalePso study and from national experts' recommendations for alternative treatment choices, with their probabilities of success taken from literature to develop country-specific models. Health benefits are measured in disease-free days (DFD). The economic analysis includes drug and physician costs. A probabilistic sensitivity analysis (PrSA) assesses the uncertainty of the model. Depending on the country, the mean total number of DFDs per patient is 21-42% higher with CPS compared with vehicle, and the mean total cost is 11-31% lower. The mean costs per DFD are 30-46% lower with CPS compared with the vehicle. The PrSA showed in 1000 simulations that CPS is more effective vs. vehicle in 100% of the cases and less expensive than its vehicle in 80-99% of the cases. This model suggests that CPS is cost-effective in maintaining the success achieved in moderate scalp psoriasis patients. © 2011 The Authors. Journal of the European Academy of Dermatology and Venereology © 2011 European Academy of Dermatology and Venereology.

Perception of teratogenic and foetotoxic risk by health professionals: a survey in Midi-Pyrenees area.

PubMed

Damase-Michel, Christine; Pichereau, Juliette; Pathak, Atul; Lacroix, Isabelle; Montastruc, Jean Louis

2008-01-01

Counselling or prescribing drugs during pregnancy requires health professionals to assess risk/benefit ratio for women and their baby. A misperception of the risk may lead to inappropriate decisions for pregnancy outcomes. The aim of the present study was to assess teratogenic and/or foetotoxic risk perception of common medications by general practitioners (GPs) and community pharmacists (CPs) from the Midi-Pyrenees area. 103 GPs and 104 CPs were interviewed. For 21 given drugs, a visual-analogue scale was used to evaluate the risk to give birth to a malformed infant if the mother had taken the drug during first trimester of pregnancy. For 9 drugs, health professionals had to say if they thought there was a potential foetotoxic and/or neonatal risk when drugs were administered during late pregnancy. 97% and 91% of GPs and CPs respectively thought that isotretinoin and thalidomide are teratogenic and more than 80% thought that amoxicillin and acetaminophen are safe in early pregnancy. However, 19% of the GPs and 33% of CPs answered there were no teratogenic risk for valproate. Around 11% of both GPs and CPs said that warfarin was safe during pregnancy. For 22% of GPs and for 13% and 27% of CPs respectively, ibuprofen and enalapril were safe on late pregnancy. For each drug, mean value of perceived teratogenic risk by health professionals was higher than values that can be found in scientific references. Concerning isotretinoin, thalidomide and metoclopramide, perceived teratogenic risk was higher for CPs. These data show that the potential teratogenic and foetotoxic risk of several commonly used drugs is unknown by health professionals. Conversely, GPs and CPs who think that a risk exists, overestimate it. This misperception can lead to inappropriate decisions for pregnancy outcomes.

Effects of acute exposure to chlorpyrifos on cholinergic and non-cholinergic targets in normal and high-fat fed male C57BL/6J mice.

PubMed

Kondakala, Sandeep; Lee, Jung Hwa; Ross, Matthew K; Howell, George E

2017-12-15

The prevalence of obesity is increasing at an alarming rate in the United States with 36.5% of adults being classified as obese. Compared to normal individuals, obese individuals have noted pathophysiological alterations which may alter the toxicokinetics of xenobiotics and therefore alter their toxicities. However, the effects of obesity on the toxicity of many widely utilized pesticides has not been established. Therefore, the present study was designed to determine if the obese phenotype altered the toxicity of the most widely used organophosphate (OP) insecticide, chlorpyrifos (CPS). Male C57BL/6J mice were fed normal or high-fat diet for 4weeks and administered a single dose of vehicle or CPS (2.0mg/kg; oral gavage) to assess cholinergic (acetylcholinesterase activities) and non-cholinergic (carboxylesterase and endocannabinoid hydrolysis) endpoints. Exposure to CPS significantly decreased red blood cell acetylcholinesterase (AChE) activity, but not brain AChE activity, in both diet groups. Further, CPS exposure decreased hepatic carboxylesterase activity and hepatic hydrolysis of a major endocannabinoid, anandamide, in a diet-dependent manner with high-fat diet fed animals being more sensitive to CPS-mediated inhibition. These in vivo studies were corroborated by in vitro studies using rat primary hepatocytes, which demonstrated that fatty acid amide hydrolase and CES activities were more sensitive to CPS-mediated inhibition than 2-arachidonoylglycerol hydrolase activity. These data demonstrate hepatic CES and FAAH activities in high-fat diet fed mice were more potently inhibited than those in normal diet fed mice following CPS exposure, which suggests that the obese phenotype may exacerbate some of the non-cholinergic effects of CPS exposure. Copyright © 2017 Elsevier Inc. All rights reserved.

Carbamoyl phosphate synthetase-1 is a rapid turnover biomarker in mouse and human acute liver injury.

PubMed

Weerasinghe, Sujith V W; Jang, You-Jin; Fontana, Robert J; Omary, M Bishr

2014-08-01

Several serum markers are used to assess hepatocyte damage, but they have limitations related to etiology specificity and prognostication. Identification of novel hepatocyte-specific biomarkers could provide important prognostic information and better pathogenesis classification. We tested the hypothesis that hepatocyte-selective biomarkers are released after subjecting isolated mouse hepatocytes to Fas-ligand-mediated apoptosis. Proteomic analysis of hepatocyte culture medium identified the mitochondrial matrix protein carbamoyl phosphate synthetase-1 (CPS1) among the most readily detected proteins that are released by apoptotic hepatocytes. CPS1 was also detected in mouse serum upon acute challenge with Fas-ligand or acetaminophen and in hepatocytes upon hypoosmotic stress, independent of hepatocyte caspase activation. Furthermore, CPS1 was observed in sera of mice chronically fed the hepatotoxin 3,5-diethoxycarbonyl-1,4-dihydrocollidine. Mouse CPS1 detectability was similar in serum and plasma, and its half-life was 126 ± 9 min. Immune staining showed that CPS1 localized to mouse hepatocytes but not ductal cells. Analysis of a few serum samples from patients with acute liver failure (ALF) due to acetaminophen, Wilson disease, or ischemia showed readily detectable CPS1 that was not observed in several patients with chronic viral hepatitis or in control donors. Notably, CPS1 rapidly decreased to undetectable levels in sera of patients with acetaminophen-related ALF who ultimately recovered, while alanine aminotransferase levels remained elevated. Therefore, CPS1 becomes readily detectable upon hepatocyte apoptotic and necrotic death in culture or in vivo. Its abundance and short serum half-life, compared with alanine aminotransferase, suggest that it may be a useful prognostic biomarker in human and mouse liver injury. Copyright © 2014 the American Physiological Society.

Continuous Palliative Sedation for Existential Distress? A Survey of Canadian Palliative Care Physicians' Views.

PubMed

Voeuk, Anna; Nekolaichuk, Cheryl; Fainsinger, Robin; Huot, Ann

2017-01-01

Palliative sedation can be used for refractory symptoms during end-of-life care. However, continuous palliative sedation (CPS) for existential distress remains controversial due to difficulty determining when this distress is refractory. The aim was to determine the opinions and practices of Canadian palliative care physicians regarding CPS for existential distress. A survey focusing on experience and views regarding CPS for existential distress was sent to 322 members of the Canadian Society of Palliative Care Physicians. Eighty-one surveys returned (accessible target, 314), resulting in a response rate of 26%. One third (31%) of the respondents reported providing CPS for existential distress. On a 5-point Likert-type scale, 40% of participants disagreed, while 43% agreed that CPS could be used for existential distress alone. Differing opinions exist regarding this complex and potentially controversial issue, necessitating the education of health-care professionals and increased awareness within the general public.

Contribution of correlated noise and selective decoding to choice probability measurements in extrastriate visual cortex.

PubMed

Gu, Yong; Angelaki, Dora E; DeAngelis, Gregory C

2014-07-01

Trial by trial covariations between neural activity and perceptual decisions (quantified by choice Probability, CP) have been used to probe the contribution of sensory neurons to perceptual decisions. CPs are thought to be determined by both selective decoding of neural activity and by the structure of correlated noise among neurons, but the respective roles of these factors in creating CPs have been controversial. We used biologically-constrained simulations to explore this issue, taking advantage of a peculiar pattern of CPs exhibited by multisensory neurons in area MSTd that represent self-motion. Although models that relied on correlated noise or selective decoding could both account for the peculiar pattern of CPs, predictions of the selective decoding model were substantially more consistent with various features of the neural and behavioral data. While correlated noise is essential to observe CPs, our findings suggest that selective decoding of neuronal signals also plays important roles.

Effects of an Attachment-based Intervention on CPS-Referred Mothers’ Event-related Potentials to Children’s Emotions

PubMed Central

Bernard, Kristin; Simons, Robert; Dozier, Mary

2015-01-01

This study examined the neurobiology of maternal sensitivity to children’s emotions among mothers involved with Child Protective Services (CPS) and low-risk comparison mothers (Mean age = 31.6 years). CPS-referred mothers participated in the Attachment and Biobehavioral Catch-up (ABC) intervention or a control intervention. Mothers’ event-related potentials (ERP) were measured while they categorized images of children with crying, laughing, and neutral expressions. CPS-referred ABC mothers (n = 19) and low-risk comparison mothers (n = 30) showed a larger enhancement of ERP responses for emotional faces relative to neutral faces than CPS-referred control mothers (n = 21). Additionally, the magnitude of ERP responses to emotional faces was associated with observed maternal sensitivity. Findings add to our understanding of the neurobiology of deficits in parenting and suggest that these deficits are changeable through a parenting intervention. PMID:26344398

The ASC/SIL ratio for cytopathologists as a quality control measure: a follow-up study.

PubMed

Nascimento, Alessandra F; Cibas, Edmund S

2007-10-01

Monitoring the relative frequency of the interpretations of atypical squamous cells (ASC) and squamous intraepithelial lesions (SIL) has been proposed as a quality control measure. To assess its value, an ASC/SIL ratio was calculated every 6 months for 3.5 years, and confidential feedback was provided to 10 cytopathologists (CPs). By using simple regression analysis, we analyzed the initial and final ASC/SIL ratios for individual CPs and for the entire group. The ratio was below the upper benchmark of 3:1 for all but 1 CP during every 6-month period. The ratio for all CPs combined showed a downward trend (from 2.05 to 1.73). The ratio for 6 CPs decreased, and for two of them the decrease was statistically significant. One CP showed a statistically significant increase in the ASC/SIL ratio. The decrease for some CPs likely reflects the salutary effect of confidential feedback and counseling.

Linking Complex Problem Solving and General Mental Ability to Career Advancement: Does a Transversal Skill Reveal Incremental Predictive Validity?

ERIC Educational Resources Information Center

Mainert, Jakob; Kretzschmar, André; Neubert, Jonas C.; Greiff, Samuel

2015-01-01

Transversal skills, such as complex problem solving (CPS) are viewed as central twenty-first-century skills. Recent empirical findings have already supported the importance of CPS for early academic advancement. We wanted to determine whether CPS could also contribute to the understanding of career advancement later in life. Towards this end, we…

Emerging Role of Clinical Preceptors (CPs) at a Private University, Karachi, Pakistan

ERIC Educational Resources Information Center

Dias, Jacqueline Maria; Lalwani, Erum; Khowaja, Amina Aijaz; Mithani, Yasmin Murad

2017-01-01

Clinical preceptors (CPs) play an integral role to prepare skilled, competent and caring student nurses to perform their future roles as members of the health care team. The aim of this study was to explore processes and effectiveness of the new role of clinical preceptors (CPs) in a low income country. A case study using Tellis (1997) approach…

Development of a cross-polarization scattering system for the measurement of internal magnetic fluctuations in the DIII-D tokamak

DOE PAGES

Rhodes, Terry L.; Peebles, William A.; Crocker, Neal A.; ...

2014-08-05

The design and performance of a new cross-polarization scattering (CPS) system for the localized measurement of internal magnetic fluctuations is presented. CPS is a process whereby magnetic fluctuations scatter incident electromagnetic radiation into a perpendicular polarization which is subsequently detected. A new CPS design that incorporates a unique scattering geometry was laboratory tested, optimized, and installed on the DIII-D tokamak. Plasma tests of signal-to-noise, polarization purity, and frequency response indicate proper functioning of the system. Lastly, CPS data show interesting features related to internal MHD perturbations known as sawteeth that are not observed on density fluctuations.

Designing interchain and intrachain properties of conjugated polymers for latent optical information encoding

DOE PAGES

Chung, Kyeongwoon; McAllister, Andrew; Bilby, David; ...

2015-09-03

Building molecular-design insights for controlling both the intrachain and the interchain properties of conjugated polymers (CPs) is essential to determine their characteristics and to optimize their performance in applications. However, most CP designs have focused on the conjugated main chain to control the intrachain properties, while the design of side chains is usually used to render CPs soluble, even though the side chains critically affect the interchain packing. Here, we present a straightforward and effective design strategy for modifying the optical and electrochemical properties of diketopyrrolopyrrole-based CPs by controlling both the intrachain and interchain properties in a single system. Themore » synthesized polymers, P1, P2 and P3, show almost identical optical absorption spectra in solution, manifesting essentially the same intrachain properties of the three CPs having restricted effective conjugation along the main chain. However, the absorption spectra of CP films are gradually tuned by controlling the interchain packing through the side-chain design. Here, based on the tailored optical properties, we demonstrate the encoding of latent optical information utilizing the CPs as security inks on a silica substrate, which reveals and conceals hidden information upon the reversible aggregation/deaggregation of CPs.« less

Designing interchain and intrachain properties of conjugated polymers for latent optical information encoding

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

Chung, Kyeongwoon; McAllister, Andrew; Bilby, David

Building molecular-design insights for controlling both the intrachain and the interchain properties of conjugated polymers (CPs) is essential to determine their characteristics and to optimize their performance in applications. However, most CP designs have focused on the conjugated main chain to control the intrachain properties, while the design of side chains is usually used to render CPs soluble, even though the side chains critically affect the interchain packing. Here, we present a straightforward and effective design strategy for modifying the optical and electrochemical properties of diketopyrrolopyrrole-based CPs by controlling both the intrachain and interchain properties in a single system. Themore » synthesized polymers, P1, P2 and P3, show almost identical optical absorption spectra in solution, manifesting essentially the same intrachain properties of the three CPs having restricted effective conjugation along the main chain. However, the absorption spectra of CP films are gradually tuned by controlling the interchain packing through the side-chain design. Here, based on the tailored optical properties, we demonstrate the encoding of latent optical information utilizing the CPs as security inks on a silica substrate, which reveals and conceals hidden information upon the reversible aggregation/deaggregation of CPs.« less

Randomized prospective study of olecranon fracture fixation: cable pin system versus tension band wiring.

PubMed

Liu, Q-H; Fu, Z-G; Zhou, J-L; Lu, T; Liu, T; Shan, L; Liu, Y; Bai, L

2012-01-01

This prospective, randomized study compared the effectiveness of the cable pin system (CPS) versus tension band wiring (TBW) for olecranon fracture fixation. Patients with acute transverse or slight oblique olecranon fractures were randomly divided into two groups: one fixed by CPS and the other by TBW. Clinical outcome data were collected and analysed following a mean duration of 21 months. The mean ± SD fracture healing time was significantly shorter in the CPS group (n = 30; 9.73 ± 2.02 weeks) compared with the TBW group (n = 32; 11.13 ± 2.21 weeks). One patient in the CPS group and seven patients in the TBW group experienced postoperative complications; this difference was statistically significant. The mean ± SD Mayo Elbow Performance Score in the CPS group was significantly higher (88.67 ± 6.42) than that in the TBW group (80.78 ± 11.99). Logistic regression analysis showed an association between fixation method and fracture healing time, complications and elbow function. Internal fixation by CPS is an effective method for olecranon fracture and is associated with a shorter healing time, fewer complications and better function than TBW.

Preparation of PLGA/Rose Bengal colloidal particles by double emulsion and layer-by-layer for breast cancer treatment.

PubMed

Loya-Castro, María F; Sánchez-Mejía, Mariana; Sánchez-Ramírez, Dante R; Domínguez-Ríos, Rossina; Escareño, Noé; Oceguera-Basurto, Paola E; Figueroa-Ochoa, Édgar B; Quintero, Antonio; Del Toro-Arreola, Alicia; Topete, Antonio; Daneri-Navarro, Adrián

2018-05-15

The use of colloidal particles (CPs) in the transport of drugs is developing rapidly thanks to its effectiveness and biosafety, especially in the treatment of various types of cancer. In this study Rose Bengal/PLGA CPs synthesized by double emulsion (W/O/W) and by electrostatic adsorption (layer-by-layer), were characterized and evaluated as potential breast cancer treatment. CPs were evaluated in terms of size, zeta potential, drug release kinetics and cell viability inhibition efficacy with the triple negative breast cancer cell line HCC70. The results showed that both types of CPs can be an excellent alternative to conventional cancer treatment by taking advantage of the enhanced permeation and retention (EPR) effect, manifested by solid tumors; however, the double emulsion CPs showed more suitable delivery times of up to 60% within two days, while layer-by-layer showed fast release of 50% in 90 min. Both types of CPs were capable to decrease cell viability, which encourage us to further testing in in vivo models to prove their efficacy and feasible use in the treatment of triple negative breast cancer. Copyright © 2018 Elsevier Inc. All rights reserved.

Cordyceps sinensis polysaccharide inhibits PDGF-BB-induced inflammation and ROS production in human mesangial cells.

PubMed

Wang, Ying; Wang, Yan; Liu, Dan; Wang, Wang; Zhao, Huan; Wang, Min; Yin, Hongping

2015-07-10

CPS-F, a polysaccharide derived from Cordyceps sinensis, is a potential anti-inflammatory and anti-oxidative agent. We demonstrated that CPS-F not only inhibits platelet-derived growth factor BB (PDGF-BB)-induced intracellular reactive oxygen species (ROS) generation, and up-regulation of tumor necrosis factor-α (TNF-α), TNF-α receptor 1 (TNFR1), and monocyte chemotactic protein-1 (MCP-1), but also acts synergistically in combination with MAPK/ERK inhibitor U0126 and PI3K/Akt inhibitor LY294002. Additionally, up-regulation of pro-inflammatory factors was reversed by use of a combination of CPS-F and NADPH oxidase (NOX) inhibitor diphenyleneiodonium chloride (DPI) or silencing of NOX1. Furthermore, CPS-F prevents the PDGF receptor β (PDGFRβ) promoter activity induced by PDGF-BB in transfected cells and ameliorates increased levels of TNF-α, TNFR1, and MCP-1 when PDGFRβ is silenced, thereby suggesting that CPS-F possesses a bidirectional regulatory function. Our findings suggest CPS-F may exert its therapeutic effect for the treatment of glomerulonephritis related to human mesangial cells (HMCs) through the ERK1/2/Akt pathways. Copyright © 2015 Elsevier Ltd. All rights reserved.

Communicating with individuals receiving home mechanical ventilation: the experiences of key communication partners.

PubMed

Laakso, Katja; Markström, Agneta; Havstam, Christina; Idvall, Markus; Hartelius, Lena

2014-01-01

The aim of the study was to explore the communication experiences of key communications partners (CPs) of individuals receiving home mechanical ventilation (HMV), with particular emphasis on the possibilities, difficulties and limitations CPs experienced in communication, possible support given to facilitate communication and exploring what made a skilled communicator. A qualitative research design using interviews was used. The participants included 19 key CPs of individuals receiving HMV. The analysis resulted in five themes: Encountering communication limitations, Functional communication strategies, Being a communication facilitator, Role insecurity and Emotional reactions and coping. The findings revealed that CPs needed to develop partly new reference frames for communication. In particular, participants emphasised the need to understand and interpret subtle details in the communicative interaction. The findings are discussed in the light of previous research, in particular an earlier study exploring another perspective; the ventilator-supported individuals' experiences of communication. Issues relating to the educational needs of CPs of individuals receiving HMV are discussed. The results are intended to enhance understanding of the challenges that individuals receiving HMV and their CPs face with communication, which should be of relevance not only to speech therapists, but for all healthcare practitioners in the field of HMV.

Improving preventive health services training in chiropractic colleges part II: enhancing outcomes through improved training and accountability processes.

PubMed

Globe, Gary; Redwood, Daniel; Brantingham, James W; Hawk, Cheryl; Terre, Lisa; Globe, Denise; Mayer, Stephan

2009-01-01

Over the past decade, chiropractic colleges have introduced clinical prevention services (CPS) training. This has included an updated public health curriculum and procedures for student interns to determine the need for preventive services and to provide these services directly or through referral to other health professionals. The purpose of this study was to evaluate the effect of a program to train chiropractic interns to deliver CPS to patients. Program evaluation used retrospective chart review, comparing the proportion of patients receiving CPS recommendations before and after implementation of the program. The main outcome measures were the percentage of appropriate CPS recommendations based upon chart reviews. Chart reviews in 2006 indicated appropriate CPS recommendations in 47.4% of cases (295/623). Chart reviews in 2007, after an additional year of sustained implementation of procedures to ensure intern and faculty accountability, showed appropriate counseling recommendations in 87% of files (137/156). Requiring interns to attend didactic presentations on CPS had no measurable effect on their performance. Major improvements occurred after a series of clinically relevant training interventions; new forms and audit procedures were implemented to increase intern and clinical faculty accountability.

Engagement and Action for Health: The Contribution of Leaders’ Collaborative Skills to Partnership Success

PubMed Central

Ansari, Walid El; Oskrochi, Reza; Phillips, Ceri

2009-01-01

A multi-site evaluation (survey) of five Kellogg-funded Community Partnerships (CPs) in South Africa was undertaken to explore the relationship between leadership skills and a range of 30 operational, functional and organisational factors deemed critical to successful CPs. The CPs were collaborative academic-health service-community efforts aimed at health professions education reforms. The level of agreement to eleven dichotomous (‘Yes/No’) leadership skills items was used to compute two measures of members’ appreciation of their CPs’ leadership. The associations between these measures and 30 CPs factors were explored, and the partnership factors that leadership skills explained were assessed after controlling. Respondents who perceived the leadership of their CPs favourably had more positive ratings across 30 other partnership factors than those who rated leadership skills less favourably, and were more likely to report a positive cost/ benefit ratio. In addition, respondents who viewed their CPs’ leadership positively also rated the operational understanding, the communication mechanisms, as well as the rules and procedures of the CPs more favourably. Leadership skills explained between 20% and 7% of the variance of 10 partnership factors. The influence of leaders’ skills in effective health-focussed partnerships is much broader than previously conceptualised. PMID:19440289

Sulfonic Groups Originated Dual-Functional Interlayer for High Performance Lithium-Sulfur Battery.

PubMed

Lu, Yang; Gu, Sui; Guo, Jing; Rui, Kun; Chen, Chunhua; Zhang, Sanpei; Jin, Jun; Yang, Jianhua; Wen, Zhaoyin

2017-05-03

The lithium-sulfur battery is one of the most prospective chemistries in secondary energy storage field due to its high energy density and high theoretical capacity. However, the dissolution of polysulfides in liquid electrolytes causes the shuttle effect, and the rapid decay of lithium sulfur battery has greatly hindered its practical application. Herein, combination of sulfonated reduced graphene oxide (SRGO) interlayer on the separator is adopted to suppress the shuttle effect. We speculate that this SRGO layer plays two roles: physically blocking the migration of polysulfide as ion selective layer and anchoring lithium polysulfide by the electronegative sulfonic group. Lewis acid-base theory and density functional theory (DFT) calculations indicate that sulfonic groups have a strong tendency to interact with lithium ions in the lithium polysulfide. Hence, the synergic effect involved by the sulfonic group contributes to the enhancement of the battery performance. Furthermore, the uniformly distributed sulfonic groups working as active sites which could induce the uniform distribution of sulfur, alleviating the excessive growth of sulfur and enhancing the utilization of active sulfur. With this interlayer, the prototype battery exhibits a high reversible discharge capacity of more than 1300 mAh g -1 and good capacity retention of 802 mAh g -1 after 250 cycles at 0.5 C rate. After 60 cycles at different rates from 0.2 to 4 C, the cell with this functional separator still recovered a high specific capacity of 1100 mAh g -1 at 0.2 C. The results demonstrate a promising interlayer design toward high performance lithium-sulfur battery with longer cycling life, high specific capacity, and rate capability.

Biomass-derived porous carbon modified glass fiber separator as polysulfide reservoir for Li-S batteries.

PubMed

Selvan, Ramakrishnan Kalai; Zhu, Pei; Yan, Chaoi; Zhu, Jiadeng; Dirican, Mahmut; Shanmugavani, A; Lee, Yun Sung; Zhang, Xiangwu

2018-03-01

Biomass-derived porous carbon has been considered as a promising sulfur host material for lithium-sulfur batteries because of its high conductive nature and large porosity. The present study explored biomass-derived porous carbon as polysulfide reservoir to modify the surface of glass fiber (GF) separator. Two different carbons were prepared from Oak Tree fruit shells by carbonization with and without KOH activation. The KOH activated porous carbon (AC) provides a much higher surface area (796 m 2  g -1 ) than pyrolized carbon (PC) (334 m 2  g -1 ). The R factor value, calculated from the X-ray diffraction pattern, revealed that the activated porous carbon contains more single-layer sheets with a lower degree of graphitization. Raman spectra also confirmed the presence of sp 3 -hybridized carbon in the activated carbon structure. The COH functional group was identified through X-ray photoelectron spectroscopy for the polysulfide capture. Simple and straightforward coating of biomass-derived porous carbon onto the GF separator led to an improved electrochemical performance in Li-S cells. The Li-S cell assembled with porous carbon modified GF separator (ACGF) demonstrated an initial capacity of 1324 mAh g -1 at 0.2 C, which was 875 mAh g -1 for uncoated GF separator (calculated based on the 2nd cycle). Charge transfer resistance (R ct ) values further confirmed the high ionic conductivity nature of porous carbon modified separators. Overall, the biomass-derived activated porous carbon can be considered as a promising alternative material for the polysulfide inhibition in Li-S batteries. Copyright © 2017 Elsevier Inc. All rights reserved.

Female sexual abuse and criminal justice intervention: a comparison of child protective service and criminal justice samples.

PubMed

Bader, Shannon M; Scalora, Mario J; Casady, Thomas K; Black, Shannon

2008-01-01

The current study compared a sample of female perpetrators reported to Child Protective Services (CPS) to a sample of women from the criminal justice system. Instead of examining a clinical or criminal justice sample in isolation, this comparison allows a more accurate description of female sexual offending. Cases were drawn from a Midwestern state's child abuse registry, law enforcement records, and sex offender registry. The CPS sample consisted of 179 women, and the criminal justice system sample consisted of 57 women. All cases were reported to the agencies between 1994 and 2004. Victims ranged in age from 1 to 18 years old (M=9.98, SD=4.37). As hypothesized, there were statistically significant differences between the CPS and criminal justice samples. Specifically, the CPS sample had a majority of victims under age 12 (74.9%), while the criminal justice sample had a majority of victims between ages 13 and 19 (73.8%). The CPS sample had predominantly intrafamilial victims (97.8%), while the criminal justice sample had a majority of extrafamilial victims (63.3%). The CPS sample also showed significantly more female victims (63.7%), while the criminal justice sample had mostly male victims (62.1%). There were significant differences in the victim's age, the victim's gender and the perpetrator-victim relationship between cases managed in the CPS and the criminal justice system. The results highlight the need for further research into child welfare and law enforcement collaboration.

Interprofessional communication between community pharmacists and general practitioners: a qualitative study.

PubMed

Weissenborn, Marina; Haefeli, Walter E; Peters-Klimm, Frank; Seidling, Hanna M

2017-06-01

Background While collaboration between community pharmacists (CPs) and general practitioners (GPs) is essential to provide comprehensive patient care, their communication often is scarce and hampered by multiple barriers. Objective We aimed to assess both professions' perceptions of interprofessional communication with regard to content and methods of communication as a basis to subsequently develop best-practice recommendations for information exchange. Setting Ambulatory care setting in Germany. Method CPs and GPs shared their experience in focus groups and in-depth interviews which were conducted using a semi-structured interview guideline. Transcribed recordings were assessed using qualitative content analysis according to Mayring. Main outcome measure Specification of existing barriers, CPs'/GPs' general perceptions of interprofessional communication and similarities and differences regarding prioritization of specific information items and how to best communicate with each other. Results Four focus groups and fourteen interviews were conducted. Seven internal (e.g. professions were not personally known to one another) and nine external barriers (e.g. mutual accessibility) were identified. Ten organizational, eight medication-related, and four patient-related information items were identified requiring interprofessional communication. Their relevance varied between the professions, e.g. CPs rated organizational issues higher than GPs. Both professions indicated communication via phone to be the most frequently used method of communication. Conclusion CPs and GPs opinions often differ. However, communication between CPs and GPs is perceived as crucial suggesting that a future concept has to offer standardized recommendations, while leaving CPs and GPs room to adjust it to their individual needs.

Rational chemical design of the carbohydrate in a glycoconjugate vaccine enhances IgM-to-IgG switching.

PubMed

Guttormsen, Hilde-Kari; Paoletti, Lawrence C; Mansfield, Keith G; Jachymek, Wojcieck; Jennings, Harold J; Kasper, Dennis L

2008-04-15

Many pathogens are sheltered from host immunity by surface polysaccharides that would be ideal as vaccines except that they are too similar to host antigens to be immunogenic. The production of functional IgG is a desirable response to vaccines; because IgG is the only isotype that crosses the placenta, it is of particular importance in maternal vaccines against neonatal disease due to group B Streptococcus (GBS). Clinical studies found a substantially lower proportion of IgG-relative to IgM-among antibodies elicited by conjugates prepared with purified GBS type V capsular polysaccharide (CPS) than among those evoked by CPSs of other GBS serotypes. The epitope specificity of IgG elicited in humans by a conjugate prepared with type V CPS is for chemically desialylated type V CPS (dV CPS). We studied desialylation as a mechanism for enhancing the ability of type V CPS to induce IgM-to-IgG switching. Desialylation did not affect the structural conformation of type V CPS. Rhesus macaques, whose isotype responses to GBS conjugates match those of humans, produced functionally active IgG in response to a dV CPS-tetanus toxoid conjugate (dV-TT), and 98% of neonatal mice born to dams vaccinated with dV-TT survived lethal challenge with viable GBS. Targeted chemical engineering of a carbohydrate to create a molecule less like host self may be a rational approach for improving other glycoconjugates.

An Examination of the Medicaid Undercount in the Current Population Survey: Preliminary Results from Record Linking

PubMed Central

Davern, Michael; Klerman, Jacob Alex; Baugh, David K; Call, Kathleen Thiede; Greenberg, George D

2009-01-01

Objective To assess reasons why survey estimates of Medicaid enrollment are 43 percent lower than raw Medicaid program enrollment counts (i.e., “Medicaid undercount”). Data Sources Linked 2000–2002 Medicaid Statistical Information System (MSIS) and the 2001–2002 Current Population Survey (CPS). Data Collection Methods Centers for Medicare and Medicaid Services provided the Census Bureau with its MSIS file. The Census Bureau linked the MSIS to the CPS data within its secure data analysis facilities. Study Design We analyzed how often Medicaid enrollees incorrectly answer the CPS health insurance item and imperfect concept alignment (e.g., inclusion in the MSIS of people who are not included in the CPS sample frame and people who were enrolled in Medicaid in more than one state during the year). Principal Findings The extent to which the Medicaid enrollee data were adjusted for imperfect concept alignment reduces the raw Medicaid undercount considerably (by 12 percentage points). However, survey response errors play an even larger role with 43 percent of Medicaid enrollees answering the CPS as though they were not enrolled and 17 percent reported being uninsured. Conclusions The CPS is widely used for health policy analysis but is a poor measure of Medicaid enrollment at any time during the year because many people who are enrolled in Medicaid fail to report it and may be incorrectly coded as being uninsured. This discrepancy should be considered when using the CPS for policy research. PMID:19187185

Segregation and Inequality in Chicago Public Schools, Transformed and Intensified under Corporate Education Reform

ERIC Educational Resources Information Center

Jankov, Pavlyn; Caref, Carol

2017-01-01

During the period of 1981 to 2015, the total population of Black students in CPS plummeted from close to 240,000, 60% of all CPS students, to 156,000 or 39% of CPS. This paper documents how despite their decreasing numbers and percentage in the system, the vast majority of Black students remained isolated in predominantly low-income Black schools…

The Effectiveness of CPS-ALM Model in Enhancing Statistical Literacy Ability and Self Concept of Elementary School Student Teacher

ERIC Educational Resources Information Center

Takaria, J.; Rumahlatu, D.

2016-01-01

The focus of this study is to examine comprehensively statistical literacy and self-concept enhancement of elementary school student teacher through CPS-BML model in which this enhancement is measured through N-gain. The result of study indicate that the use of Collaborative Problem Solving Model assisted by literacy media (CPS-ALM) model…

Mapping an Experiment-Based Assessment of Collaborative Behavior onto Collaborative Problem Solving in PISA 2015: A Cluster Analysis Approach for Collaborator Profiles

ERIC Educational Resources Information Center

Herborn, Katharina; Mustafic, Maida; Greiff, Samuel

2017-01-01

Collaborative problem solving (CPS) assessment is a new academic research field with a number of educational implications. In 2015, the Programme for International Student Assessment (PISA) assessed CPS with a computer-simulated human-agent (H-A) approach that claimed to measure 12 individual CPS skills for the first time. After reviewing the…

Agricultural conservation practices can help mitigate the impact of climate change.

PubMed

Wagena, Moges B; Easton, Zachary M

2018-09-01

Agricultural conservation practices (CPs) are commonly implemented to reduce diffuse nutrient pollution. Climate change can complicate the development, implementation, and efficiency of agricultural CPs by altering hydrology, nutrient cycling, and erosion. This research quantifies the impact of climate change on hydrology, nutrient cycling, erosion, and the effectiveness of agricultural CP in the Susquehanna River Basin in the Chesapeake Bay Watershed, USA. We develop, calibrate, and test the Soil and Water Assessment Tool-Variable Source Area (SWAT-VSA) model and select four CPs; buffer strips, strip-cropping, no-till, and tile drainage, to test their effectiveness in reducing climate change impacts on water quality. We force the model with six downscaled global climate models (GCMs) for a historic period (1990-2014) and two future scenario periods (2041-2065 and 2075-2099) and quantify the impact of climate change on hydrology, nitrate-N (NO 3 -N), total N (TN), dissolved phosphorus (DP), total phosphorus (TP), and sediment export with and without CPs. We also test prioritizing CP installation on the 30% of agricultural lands that generate the most runoff (e.g., critical source areas-CSAs). Compared against the historical baseline and with no CPs, the ensemble model predictions indicate that climate change results in annual increases in flow (4.5±7.3%), surface runoff (3.5±6.1%), sediment export (28.5±18.2%) and TN export (9.5±5.1%), but decreases in NO 3 -N (12±12.8%), DP (14±11.5), and TP (2.5±7.4%) export. When agricultural CPs are simulated most do not appreciably change the water balance, however, tile drainage and strip-cropping decrease surface runoff, sediment export, and DP/TP, while buffer strips reduce N export. Installing CPs on CSAs results in nearly the same level of performance for most practices and most pollutants. These results suggest that climate change will influence the performance of agricultural CPs and that targeting agricultural CPs to CSAs can provide nearly the same level of water quality effects as more widespread adoption. Copyright © 2018 Elsevier B.V. All rights reserved.

Customer premises services market demand assessment 1980 - 2000. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Gamble, R. B.; Saporta, L.; Heidenrich, G. A.

1983-01-01

Estimates of market demand for domestic civilian telecommunications services for the years 1980 to 2000 are provided. Overall demand, demand or satellite services, demand for satellite delivered Customer Premises Service (CPS), and demand for 30/20 GHz Customer Premises Services are covered. Emphasis is placed on the CPS market and demand is segmented by market, by service, by user class and by geographic region. Prices for competing services are discussed and the distribution of traffic with respect to distance is estimated. A nationwide traffic distribution model for CPS in terms of demand for CPS traffic and earth stations for each of the major SMSAs in the United States are provided.

Amorphous MoS3 as the sulfur-equivalent cathode material for room-temperature Li-S and Na-S batteries.

PubMed

Ye, Hualin; Ma, Lu; Zhou, Yu; Wang, Lu; Han, Na; Zhao, Feipeng; Deng, Jun; Wu, Tianpin; Li, Yanguang; Lu, Jun

2017-12-12

Many problems associated with Li-S and Na-S batteries essentially root in the generation of their soluble polysulfide intermediates. While conventional wisdom mainly focuses on trapping polysulfides at the cathode using various functional materials, few strategies are available at present to fully resolve or circumvent this long-standing issue. In this study, we propose the concept of sulfur-equivalent cathode materials, and demonstrate the great potential of amorphous MoS 3 as such a material for room-temperature Li-S and Na-S batteries. In Li-S batteries, MoS 3 exhibits sulfur-like behavior with large reversible specific capacity, excellent cycle life, and the possibility to achieve high areal capacity. Most remarkably, it is also fully cyclable in the carbonate electrolyte under a relatively high temperature of 55 °C. MoS 3 can also be used as the cathode material of even more challenging Na-S batteries to enable decent capacity and good cycle life. Operando X-ray absorption spectroscopy (XAS) experiments are carried out to track the structural evolution of MoS 3 It largely preserves its chain-like structure during repetitive battery cycling without generating any free polysulfide intermediates.

Efficacy of tray adhesives for the adhesion of elastomer rubber impression materials to impression modeling plastics for border molding.

PubMed

Nishigawa, G; Sato, T; Suenaga, K; Minagi, S

1998-02-01

Tray adhesive, which is used for the adhesion of elastomer rubber impression materials to a custom resin tray, lowers the retention of the impression materials to the impression modeling plastics, as some ingredients of tray adhesive make the impression modeling plastic soft and tacky. The efficacy of tray adhesive, which is used for the adhesion of elastomer rubber impression materials to a custom resin tray, on the adhesion between elastomer rubber impression material and impression modeling plastic was investigated. Four silicone rubber impression materials (two addition reaction types and two condensation reaction types), two polysulfide rubber impression materials, and one impression modeling plastic were used in this study. Tensile strength between elastomer rubber impression material and impression modeling plastic with or without the application of tray adhesive was evaluated. Although tray adhesives for both addition reaction type and both condensation reaction type of silicone impression materials and one tray adhesive for polysulfide rubber impression material increased the tensile strength between the impression material and impression modeling plastic, one tray adhesive for polysulfide rubber impression material decreased the tensile strength when sufficient drying time was not applied.

Fluorinated, Sulfur-Rich, Covalent Triazine Frameworks for Enhanced Confinement of Polysulfides in Lithium-Sulfur Batteries.

PubMed

Xu, Fei; Yang, Shuhao; Jiang, Guangshen; Ye, Qian; Wei, Bingqing; Wang, Hongqiang

2017-11-01

Lithium-sulfur battery represents a promising class of energy storage technology owing to its high theoretical energy density and low cost. However, the insulating nature, shuttling of soluble polysulfides and volumetric expansion of sulfur electrodes seriously give rise to the rapid capacity fading and low utilization. In this work, these issues are significantly alleviated by both physically and chemically restricting sulfur species in fluorinated porous triazine-based frameworks (FCTF-S). One-step trimerization of perfluorinated aromatic nitrile monomers with elemental sulfur allows the simultaneous formation of fluorinated triazine-based frameworks, covalent attachment of sulfur and its homogeneous distribution within the pores. The incorporation of electronegative fluorine in frameworks provides a strong anchoring effect to suppress the dissolution and accelerate the conversion of polysulfides. Together with covalent chemical binding and physical nanopore-confinement effects, the FCTF-S demonstrates superior electrochemical performances, as compared to those of the sulfur-rich covalent triazine-based framework without fluorine (CTF-S) and porous carbon delivering only physical confinement. Our approach demonstrates the potential of regulating lithium-sulfur battery performances at a molecular scale promoted by the porous organic polymers with a flexible design.

Reactivation of dead sulfide species in lithium polysulfide flow battery for grid scale energy storage.

PubMed

Jin, Yang; Zhou, Guangmin; Shi, Feifei; Zhuo, Denys; Zhao, Jie; Liu, Kai; Liu, Yayuan; Zu, Chenxi; Chen, Wei; Zhang, Rufan; Huang, Xuanyi; Cui, Yi

2017-09-06

Lithium polysulfide batteries possess several favorable attributes including low cost and high energy density for grid energy storage. However, the precipitation of insoluble and irreversible sulfide species on the surface of carbon and lithium (called "dead" sulfide species) leads to continuous capacity degradation in high mass loading cells, which represents a great challenge. To address this problem, herein we propose a strategy to reactivate dead sulfide species by reacting them with sulfur powder with stirring and heating (70 °C) to recover the cell capacity, and further demonstrate a flow battery system based on the reactivation approach. As a result, ultrahigh mass loading (0.125 g cm -3 , 2 g sulfur in a single cell), high volumetric energy density (135 Wh L -1 ), good cycle life, and high single-cell capacity are achieved. The high volumetric energy density indicates its promising application for future grid energy storage.Lithium polysulfide batteries suffer from the precipitation of insoluble and irreversible sulfide species on the surface of carbon and lithium. Here the authors show a reactivation strategy by a reaction with cheap sulfur powder under stirring and heating to recover the cell capacity.

Amorphous MoS3 as the sulfur-equivalent cathode material for room-temperature Li–S and Na–S batteries

PubMed Central

Ye, Hualin; Ma, Lu; Zhou, Yu; Wang, Lu; Han, Na; Zhao, Feipeng; Deng, Jun; Wu, Tianpin; Li, Yanguang; Lu, Jun

2017-01-01

Many problems associated with Li–S and Na–S batteries essentially root in the generation of their soluble polysulfide intermediates. While conventional wisdom mainly focuses on trapping polysulfides at the cathode using various functional materials, few strategies are available at present to fully resolve or circumvent this long-standing issue. In this study, we propose the concept of sulfur-equivalent cathode materials, and demonstrate the great potential of amorphous MoS3 as such a material for room-temperature Li–S and Na–S batteries. In Li–S batteries, MoS3 exhibits sulfur-like behavior with large reversible specific capacity, excellent cycle life, and the possibility to achieve high areal capacity. Most remarkably, it is also fully cyclable in the carbonate electrolyte under a relatively high temperature of 55 °C. MoS3 can also be used as the cathode material of even more challenging Na–S batteries to enable decent capacity and good cycle life. Operando X-ray absorption spectroscopy (XAS) experiments are carried out to track the structural evolution of MoS3. It largely preserves its chain-like structure during repetitive battery cycling without generating any free polysulfide intermediates. PMID:29180431

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

Wujcik, Kevin H.; Wang, Dunyang Rita; Pascal, Tod A.

Lithium sulfur (Li-S) batteries are well known for their high theoretical specific capacities, but are plagued with scientific obstacles that make practical implementation of the technology impossible. The success of Li-S batteries will likely necessitate the use of thick sulfur cathodes that enable high specific energy densities. However, little is known about the fundamental reaction mechanisms and chemical processes that take place in thick cathodes, as most research has focused on studying thinner cathodes that enable high performance. In this study, in situ X-ray absorption spectroscopy at the sulfur K-edge is used to examine the back of a 115 μmmore » thick Li-S cathode during discharge. Our results show that in such systems, where electrochemical reactions between sulfur and lithium are likely to proceed preferentially toward the front of the cathode, lithium polysulfide dianions formed in this region diffuse to the back of the cathode during discharge. We show that high conversion of elemental sulfur is achieved by chemical reactions between elemental sulfur and polysulfide dianions of intermediate chain length (Li 2S x, 4 ≤ x ≤ 6). Our work suggests that controlling the formation and diffusion of intermediate chain length polysulfide dianions is crucial for insuring full utilization of thick sulfur cathodes.« less

What Happened Next: Interviews With Mothers After a Finding of Child Maltreatment in the Household.

PubMed

Campbell, Kristine A; Olson, Lenora M; Keenan, Heather T; Morrow, Susan L

2017-01-01

Child Protective Services (CPS) identifies over 700,000 victims of child maltreatment in the United States annually. Research shows that risk factors for these children may persist despite CPS intervention. Mothers have unique and often untapped perspectives on the experiences and consequences of CPS intervention that may inform future practice. We explored these perspectives through interviews with 24 mothers after a first-time CPS finding of maltreatment not resulting in out-of-home placement. Male partners were primary perpetrators in 21 cases, with mothers or sitters identified as perpetrators in remaining cases. Data were analyzed using grounded theory. Mothers described risk factors or Roots of maltreatment prior to CPS involvement and reported variable experiences with Recognition of and Response to maltreatment. Divergent Outcomes emerged: I Feel Stronger and We're No Better These findings provide an understanding of household experiences around child maltreatment that may support practice and policy changes to improve outcomes for vulnerable children. © The Author(s) 2016.

Effects of light wavelengths on extracellular and capsular polysaccharide production by Nostoc flagelliforme.

PubMed

Han, Pei-pei; Sun, Ying; Jia, Shi-ru; Zhong, Cheng; Tan, Zhi-lei

2014-05-25

The influences of different wavelengths of light (red 660nm, yellow 590nm, green 520nm, blue 460nm, purple 400nm) and white light on extracellular polysaccharide (EPS) and capsular polysaccharide (CPS) production by Nostoc flagelliforme in liquid culture were demonstrated in this study. The results showed that, compared with white light, red and blue lights significantly increased both EPS and CPS production while yellow light reduced their production; purple and green lights stimulated EPS production but inhibited CPS formation. Nine constituent monosaccharides and one uronic acid were detected in both EPS and CPS, and their ratios showed significant differences among treatment with different light wavelengths. However, the advanced structure of EPS and CPS from various light conditions did not present obvious difference through Fourier transform infrared spectroscopy and X-ray diffraction characterization. These findings establish a basis for development of high-yielding polysaccharide production process and understanding their regulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Polysaccharides from by-products of the Wonderful and Laffan pomegranate varieties: New insight into extraction and characterization.

PubMed

Khatib, Mohamad; Giuliani, Camilla; Rossi, Federico; Adessi, Alessandra; Al-Tamimi, Amal; Mazzola, Giuseppe; Di Gioia, Diana; Innocenti, Marzia; Mulinacci, Nadia

2017-11-15

The main crude polysaccharides (CPS), extracted from two widely cultivated pomegranate varieties, Laffan and Wonderful, were studied and characterized. We obtained the highest CPS extraction yield (approximatively 10% w/w on dried matter) by 1h of decoction (ratio 1/40w/v). The predominant polymers (75-80%) of the CPS samples showed a hydrodynamic volume close to 2000kDa by size exclusion chromatography and the exocarp and mesocarp profiles were very similar. The proton spectra ( 1 H NMR), according to sugar composition and gelling ability, confirmed the main polysaccharide fractions were pectin with different acylation and methylation degree. The CPS from Laffan and Wonderful mesocarp showed prebiotic properties in vitro with Lactobacillus and Bifidobacterium strains. The composition of the decoction (12% ellagitannins and 10% of CPS) obtained by a green extraction process of pomegranate by-products, makes it a suitable component of functional food formulations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Child protection services and parents with intellectual and developmental disabilities.

PubMed

LaLiberte, Traci; Piescher, Kristine; Mickelson, Nicole; Lee, Mi Hwa

2017-05-01

Information about parents with intellectual and developmental disabilities (IDD) in the child protection system (CPS) continues to evolve. This study examined characteristics, experiences and representation of parents with IDD across three CPS decision points, as compared to parents with other disabilities and parents without disabilities in the United States. The sample consisted of 303,039 individuals: 2,081 were individuals identified as parents in a CPS investigation; 1,101 had children in out-of-home care (OHC); and 308 experienced termination of parental rights (TPR). Descriptive statistics, chi-square analysis, disparity indices and logistic regression were employed. Parents with IDD were significantly more likely than parents without disabilities (but not significantly more likely than parents with other types of disabilities) to experience disproportionately representation. Parents with IDD are generally over-represented within CPS; however, this representation is dependent upon the comparison group utilized and other risk factors. CPS system-level changes are necessary. © 2016 John Wiley & Sons Ltd.

Altitude profiles of total chlorinated paraffins in humus and spruce needles from the Alps (MONARPOP).

PubMed

Iozza, Saverio; Schmid, Peter; Oehme, Michael; Bassan, Rodolfo; Belis, Claudio; Jakobi, Gert; Kirchner, Manfred; Schramm, Karl-Werner; Kräuchi, Norbert; Moche, Wolfgang; Offenthaler, Ivo; Weiss, Peter; Simoncic, Primoz; Knoth, Wilhelm

2009-12-01

Chlorinated paraffins (CPs) are toxic, bioaccumulative, persistent, and ubiquitously present in the environment. CPs were analyzed in humus and needle samples, which were taken within the Monitoring Network in the Alpine Region for Persistent and other Organic Pollutants (MONARPOP) at sampling sites of 7 different altitude profiles in the Alps. Gas chromatography combined with electron ionization tandem mass spectrometry (EI-MS/MS) was used for the determination of total CPs (sum of short, medium and long chain CPs). CPs were found in all samples; the concentrations varied between 7 and 199 ng g(-1) dry weight (dw) and within 26 and 460 ng g(-1) dw in humus and needle samples, respectively. A clear vertical tendency within the individual altitude profiles could not be ascertained. Within all altitude profiles, elevated concentrations were observed in humus samples taken between 700 and 900 m and between 1300 and 1500 m. In the needle samples no similar correlation could be observed due to higher variation of the data.

The anthelmintic efficacy of natural plant cysteine proteinases against the equine tapeworm, Anoplocephala perfoliata in vitro.

PubMed

Mansur, F; Luoga, W; Buttle, D J; Duce, I R; Lowe, A E; Behnke, J M

2016-09-01

Papaya latex has been demonstrated to be an efficacious anthelmintic against murine, porcine, ovine and canine nematode parasites, and even those infecting poultry, and it has some efficacy against rodent cestodes. The active ingredients of papaya latex are known to be cysteine proteinases (CPs). The experiments described in this paper indicate that CPs in papaya latex, and also those in pineapples, are highly efficacious against the equine cestode Anoplocephala perfoliata in vitro, by causing a significant reduction in motility leading to death of the worms. The susceptibility of A. perfoliata to damage by CPs was considerably greater than that of the rodent cestodes Hymenolepis diminuta and H. microstoma. Our results are the first to report anthelmintic efficacy of CPs against an economically important equine helminth. Moreover, they provide further evidence that the spectrum of activity of CPs is not restricted to nematodes and support the idea that these plant-derived enzymes can be developed into useful broad-spectrum anthelmintics.

The preparation of three selenium-containing Cordyceps militaris polysaccharides: Characterization and anti-tumor activities.

PubMed

Liu, Fei; Zhu, Zhen-Yuan; Sun, Xiaoli; Gao, Hui; Zhang, Yong-Min

2017-06-01

In the present work, three fractions of selenized Cordyceps militaris polysaccharides (SeCPS) named SeCPS- I, SeCPS- II and SeCPS- III were isolated and purified by ultra-filtration. Their selenium content were measured as 541.3, 863.7 and 623.3μg/g respectively by a graphite furnace atomic absorption spectroscopy. The monosaccharide comformation analysis showed that they were mainly consisted of D-Mannose, D-Glucose, and D-Galactose in mole ratios of 1:7.63:0.83, 1:1.34:0.31 and 1:3.77:0.41 respectively. Their structure characteristics were compared by IFR and NMR spectroscopy. Scanning electron microscopy (SEM) and Congo red (CR) spectrophotometric method were used to investigate their morphological characteristics and conformational transition. SeCPS-II showed the strongest anti-tumor effects judging from the result of in vitro anti-tumor assays against two tumor cell lines (hepatocellular carcinoma HepG-2 cells and lung adenocarcinom A549 cells). Copyright © 2017 Elsevier B.V. All rights reserved.

Contribution of correlated noise and selective decoding to choice probability measurements in extrastriate visual cortex

PubMed Central

Gu, Yong; Angelaki, Dora E; DeAngelis, Gregory C

2014-01-01

Trial by trial covariations between neural activity and perceptual decisions (quantified by choice Probability, CP) have been used to probe the contribution of sensory neurons to perceptual decisions. CPs are thought to be determined by both selective decoding of neural activity and by the structure of correlated noise among neurons, but the respective roles of these factors in creating CPs have been controversial. We used biologically-constrained simulations to explore this issue, taking advantage of a peculiar pattern of CPs exhibited by multisensory neurons in area MSTd that represent self-motion. Although models that relied on correlated noise or selective decoding could both account for the peculiar pattern of CPs, predictions of the selective decoding model were substantially more consistent with various features of the neural and behavioral data. While correlated noise is essential to observe CPs, our findings suggest that selective decoding of neuronal signals also plays important roles. DOI: http://dx.doi.org/10.7554/eLife.02670.001 PMID:24986734

Is the Diagnosis of Physical Abuse Changed when Child Protective Services Consults a Child Abuse Pediatrics Subspecialty Group as a Second Opinion?

ERIC Educational Resources Information Center

Anderst, James; Kellogg, Nancy; Jung, Inkyung

2009-01-01

Objectives: To characterize the changes regarding the diagnosis of physical abuse provided to Child Protective Services (CPS) when CPS asks a Child Abuse Pediatrics (CAP) specialty group for a second opinion and works in concert with that CAP group. Methods: Subjects were reported to CPS for suspected physical abuse and were first evaluated by a…

Suitable areas of Phakopsora pachyrhizi, Spodoptera exigua, and their host plant Phaseolus vulgaris are projected to reduce and shift due to climate change

NASA Astrophysics Data System (ADS)

Ramirez-Cabral, Nadiezhda Yakovleva Zitz; Kumar, Lalit; Shabani, Farzin

2018-01-01

Worldwide, crop pests (CPs) such as pathogens and insects affect agricultural production detrimentally. Species distribution models can be used for projecting current and future suitability of CPs and host crop localities. Our study overlays the distribution of two CPs (Asian soybean rust and beet armyworm) and common bean, a potential host of them, in order to determine their current and future levels of coexistence. This kind of modeling approach has rarely been performed previously in climate change studies. The soybean rust and beet armyworm model projections herein show a reduction of the worldwide area with high and medium suitability of both CPs and a movement of them away from the Equator, in 2100 more pronounced than in 2050. Most likely, heat and dry stress will be responsible for these changes. Heat and dry stress will greatly reduce and shift the future suitable cultivation area of common bean as well, in a similar manner. The most relevant findings of this study were the reduction of the suitable areas for the CPs, the reduction of the risk under future scenarios, and the similarity of trends for the CPs and host. The current results highlight the relation between and the coevolution of host and pathogens.

The effect of creative problem solving on students’ mathematical adaptive reasoning

NASA Astrophysics Data System (ADS)

Muin, A.; Hanifah, S. H.; Diwidian, F.

2018-01-01

This research was conducted to analyse the effect of creative problem solving (CPS) learning model on the students’ mathematical adaptive reasoning. The method used in this study was a quasi-experimental with randomized post-test only control group design. Samples were taken as many as two classes by cluster random sampling technique consisting of experimental class (CPS) as many as 40 students and control class (conventional) as many as 40 students. Based on the result of hypothesis testing with the t-test at the significance level of 5%, it was obtained that significance level of 0.0000 is less than α = 0.05. This shows that the students’ mathematical adaptive reasoning skills who were taught by CPS model were higher than the students’ mathematical adaptive reasoning skills of those who were taught by conventional model. The result of this research showed that the most prominent aspect of adaptive reasoning that could be developed through a CPS was inductive intuitive. Two aspects of adaptive reasoning, which were inductive intuitive and deductive intuitive, were mostly balanced. The different between inductive intuitive and deductive intuitive aspect was not too big. CPS model can develop student mathematical adaptive reasoning skills. CPS model can facilitate development of mathematical adaptive reasoning skills thoroughly.

External Exposure to Short- and Medium-Chain Chlorinated Paraffins for the General Population in Beijing, China.

PubMed

Gao, Wei; Cao, Dandan; Wang, Yingjun; Wu, Jing; Wang, Ying; Wang, Yawei; Jiang, Guibin

2018-01-02

Chlorinated paraffins (CPs) are a class of compounds that are currently produced and used in large amounts in commercial products worldwide. In this study, food, indoor air, indoor dust, and drinking water samples were collected to evaluate the external exposure levels of CPs and possible pathway for the general population in Beijing, China. Short chain CPs (SCCPs) and medium chain CPs (MCCPs) in 199 samples were analyzed using a gas chromatography tandem time-of-flight high-resolution mass spectrometry (GC-TOF-HR-MS) method. High levels of CPs were observed in the indoor environment from residential houses, offices, and student dormitories. The geometric mean concentrations (GM) of ∑SCCPs and ∑MCCPs in indoor dust were 92 μg g -1 and 82 μg g -1 , respectively, while in indoor air, the concentrations were 80 ng m -3 and 3.4 ng m -3 , respectively. The GM of ∑SCCPs and ∑MCCPs in the diet were 83 ng g -1 dry weight (dw) and 56 ng g -1 dw, respectively. The most important external exposure routes to CPs to the general populations in Beijing were food intake and indoor dust ingestion. Indoor dust and indoor air posed higher risks for toddlers and infants than for adults.

Human adipose stem cell and ASC-derived cardiac progenitor cellular therapy improves outcomes in a murine model of myocardial infarction

PubMed Central

Davy, Philip MC; Lye, Kevin D; Mathews, Juanita; Owens, Jesse B; Chow, Alice Y; Wong, Livingston; Moisyadi, Stefan; Allsopp, Richard C

2015-01-01

Background Adipose tissue is an abundant and potent source of adult stem cells for transplant therapy. In this study, we present our findings on the potential application of adipose-derived stem cells (ASCs) as well as induced cardiac-like progenitors (iCPs) derived from ASCs for the treatment of myocardial infarction. Methods and results Human bone marrow (BM)-derived stem cells, ASCs, and iCPs generated from ASCs using three defined cardiac lineage transcription factors were assessed in an immune-compromised mouse myocardial infarction model. Analysis of iCP prior to transplant confirmed changes in gene and protein expression consistent with a cardiac phenotype. Endpoint analysis was performed 1 month posttransplant. Significantly increased endpoint fractional shortening, as well as reduction in the infarct area at risk, was observed in recipients of iCPs as compared to the other recipient cohorts. Both recipients of iCPs and ASCs presented higher myocardial capillary densities than either recipients of BM-derived stem cells or the control cohort. Furthermore, mice receiving iCPs had a significantly higher cardiac retention of transplanted cells than all other groups. Conclusion Overall, iCPs generated from ASCs outperform BM-derived stem cells and ASCs in facilitating recovery from induced myocardial infarction in mice. PMID:26604802

Towards a Semantic Web of Things: A Hybrid Semantic Annotation, Extraction, and Reasoning Framework for Cyber-Physical System.

PubMed

Wu, Zhenyu; Xu, Yuan; Yang, Yunong; Zhang, Chunhong; Zhu, Xinning; Ji, Yang

2017-02-20

Web of Things (WoT) facilitates the discovery and interoperability of Internet of Things (IoT) devices in a cyber-physical system (CPS). Moreover, a uniform knowledge representation of physical resources is quite necessary for further composition, collaboration, and decision-making process in CPS. Though several efforts have integrated semantics with WoT, such as knowledge engineering methods based on semantic sensor networks (SSN), it still could not represent the complex relationships between devices when dynamic composition and collaboration occur, and it totally depends on manual construction of a knowledge base with low scalability. In this paper, to addresses these limitations, we propose the semantic Web of Things (SWoT) framework for CPS (SWoT4CPS). SWoT4CPS provides a hybrid solution with both ontological engineering methods by extending SSN and machine learning methods based on an entity linking (EL) model. To testify to the feasibility and performance, we demonstrate the framework by implementing a temperature anomaly diagnosis and automatic control use case in a building automation system. Evaluation results on the EL method show that linking domain knowledge to DBpedia has a relative high accuracy and the time complexity is at a tolerant level. Advantages and disadvantages of SWoT4CPS with future work are also discussed.

Left-right and Yin-Yang balance of biophoton emission from hands.

PubMed

Yang, Joon-mo; Choi, Chunho; Hyun-hee; Woo, Won-myung; Yi, Seung-ho; Soh, Kwang-sup; Yang, Jong Soo; Choi, C

2004-01-01

Yearlong measurements of biophotons from palm and back of hand of three healthy people were performed. The detection of biophoton was done with two photomultiplier tubes whose spectral range was from 300 nm to 650 nm. The measurement was done on a circular area of diameter 46 mm whose centers were at the acupuncture point Laogong (PC8) of a palm and the mid-point of a back, respectively. The emission rates from the dorsa showed strong seasonal dependence which is consistent with the active nature of Yang meridians, while the palm sides show less seasonal dependence as they belong to the passive Yin meridians. This could be quantified simply by the standard deviations from the yearly average: They were 47.6 counts per second (cps), 66.1 cps and 66.0 cps from the dorsa, and 23.8 cps, 29.7 cps and 30.4 cps from the palms of subject 1, 2 and 3, respectively. Biophoton emission revealed qualitative individual tendencies: The subjects 1 and 2 emitted more strongly from the left dorsa, while the subject 3 from the right dorsum. The left-right balance of biophoton emission was well kept for normal people, which is in contrast with the severe imbalance for some stroke patients. Thus biophoton measurement has a diagnostic potential that encourages more studies.

Ensemble coding of face identity is present but weaker in congenital prosopagnosia.

PubMed

Robson, Matthew K; Palermo, Romina; Jeffery, Linda; Neumann, Markus F

2018-03-01

Individuals with congenital prosopagnosia (CP) are impaired at identifying individual faces but do not appear to show impairments in extracting the average identity from a group of faces (known as ensemble coding). However, possible deficits in ensemble coding in a previous study (CPs n = 4) may have been masked because CPs relied on pictorial (image) cues rather than identity cues. Here we asked whether a larger sample of CPs (n = 11) would show intact ensemble coding of identity when availability of image cues was minimised. Participants viewed a "set" of four faces and then judged whether a subsequent individual test face, either an exemplar or a "set average", was in the preceding set. Ensemble coding occurred when matching (vs. mismatching) averages were mistakenly endorsed as set members. We assessed both image- and identity-based ensemble coding, by varying whether test faces were either the same or different images of the identities in the set. CPs showed significant ensemble coding in both tasks, indicating that their performance was independent of image cues. As a group, CPs' ensemble coding was weaker than controls in both tasks, consistent with evidence that perceptual processing of face identity is disrupted in CP. This effect was driven by CPs (n= 3) who, in addition to having impaired face memory, also performed particularly poorly on a measure of face perception (CFPT). Future research, using larger samples, should examine whether deficits in ensemble coding may be restricted to CPs who also have substantial face perception deficits. Copyright © 2018 Elsevier Ltd. All rights reserved.

Measuring the involvement of people with HIV in treatment decision making using the control preferences scale.

PubMed

Kremer, Heidemarie; Ironson, Gail

2008-01-01

Since 1983, HIV patients have been advocating for participatory decision making. This study measures the involvement that HIV-positive people perceive in treatment decision making. A secondary objective is to assess the validity of the instrument used to examine decisional roles, the Control Preferences Scale (CPS). The authors interviewed 79 HIV-positive people, a sub-sample of a study on long survival with HIV, diverse with respect to ethnicity, age, gender, and sexual orientation. They compared the self- and researcher-rated decisional roles of participants on the CPS. They also assessed how well the CPS corresponds with Charles's paternalistic, shared- and informed-choice models of decision making about treatment based on decisional roles and information exchange. Most participants (75%) perceived collaborative/active involvement in decision making. Agreement (Kendall's tau-b) between self- and researcher-rated decisional roles on the CPS was 0.82, whereas agreement between self-ratings on the CPS and researcher ratings on Charles's classification was 0.60. Charles's classification was difficult if participants had chosen not to take their prescribed medication without being adequately informed about the risky consequences of this decision. In this study, HIV-positive people perceived a high level of involvement in decision making. Reliability and convergent validity of the CPS was high. Charles's classification was problematic because decisional roles and information exchange are distinct dimensions. Some people make risky treatment decisions on their own without being adequately informed. The CPS is a useful instrument to measure decisional role perceptions of HIV-positive people but needs to be complemented by an instrument measuring treatment knowledge.

Continuous palliative sedation: not only a response to physical suffering.

PubMed

Swart, Siebe J; van der Heide, Agnes; van Zuylen, Lia; Perez, Roberto S G M; Zuurmond, Wouter W A; van der Maas, Paul J; van Delden, Johannes J M; Rietjens, Judith A C

2014-01-01

Palliative sedation is a medical intervention aimed at relieving symptoms that can no longer be controlled by conventional treatment. Ample knowledge is available regarding the nature of such symptoms, but there is no in-depth information regarding how health care workers decide about palliative sedation. The study objective was to investigate considerations concerning the indications for continuous palliative sedation (CPS) and issues that influence these considerations. The study consisted of qualitative interviews regarding patients who had recently received CPS. The study involved physicians and nurses working in general practice, nursing homes, and hospitals. Analyses by a multidisciplinary research team used the constant comparative method. Together with physical symptoms, psychological and existential suffering may combine to produce a refractory state for which other treatment options than CPS were not available or considered inappropriate. A limited life expectancy was by many considered crucial (e.g., to avoid hastening death) and by some less important (e.g., because the patient's suffering was considered to be key). Issues influencing the decision to use CPS related to patient preferences (e.g., dignity, not wanting to experience further suffering) or family issues (impact of suffering on family, family requesting CPS). The indication for CPS typically originates from physical symptoms and nonphysical problems producing a refractory state in which a patient suffers unbearably. In such states, preferences of patients and families and the life expectancy criterion are weighed against the severity of refractory symptoms. Therefore the use of CPS is not only a response to the physical suffering of patients in the dying phase.

Incongruence between women's survey- and interview-determined decision control preferences: A mixed methods study of decision-making in metastatic breast cancer.

PubMed

Ejem, Deborah; Dionne-Odom, J Nicholas; Turkman, Yasemin; Knight, Sara J; Willis, Dan; Kaufman, Peter A; Bakitas, Marie

2018-04-30

Women with metastatic breast cancer face numerous, complex treatment and advance care planning (ACP) decisions. Our aim was to develop a better understanding of women with metastatic breast cancer's decision-making preferences overtime and relative to specific types of decisions. Convergent, parallel mixed-methods study. Participants completed the Control Preferences Scale (CPS) and a semi-structured interview of decision-making experiences at enrollment (T1; n = 22) and when facing a decision or 3 months later (T2; n = 19). We categorized women's decision-making experience descriptions into one of the CPS decisional styles and compared them to their CPS response. We constructed an analytic grid that aligned the interview-determined treatment and ACP decisional preferences with the CPS categories at T1 and T2 and calculated Cohen's kappa coefficient and congruence percentages. Participants (n = 22) were White (100%), averaged 62 years, married (54%), retired (45%), and had a bachelor's degree (45%). Congruence between CPS response and interview-determined treatment preferences at T1 was 32% (kappa = 0.083) and 33% (kappa = 0.120) at T2. Congruence between CPS survey response and interview-determined ACP preferences at T1 was 22.7% (kappa =0.092) at T1 and 11% (kappa = 0.011) at T2. Although women selected a "shared" treatment decision-making style using the CPS validated tool, when interviewed their descriptions generally reflected a passive process in which they followed the oncologists' treatment suggestions. Future research should explore whether the incongruence between stated and actual decision-making style is a function of misinterpreting the CPS choices or a true inconsistency that could lead to adverse consequences such as decisional regret. Copyright © 2018 John Wiley & Sons, Ltd.

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

Bisht, Kamal Kumar; Rachuri, Yadagiri; Academy of Scientific and Innovative Research

Four ternary coordination polymers (CPs) namely, ([Ni(SDB)(BITMB)(H{sub 2}O)]·H{sub 2}O){sub n} (CP1), ([Cd(SDB)(BITMB) (H{sub 2}O)]·(THF)(H{sub 2}O)){sub n} (CP2), ([Zn{sub 2}(SDB){sub 2}(BITMB)]·(THF){sub 2}){sub n} (CP3) and ([Co{sub 2}(SDB){sub 2}(BITMB)]·(Dioxane){sub 3}){sub n} (CP4) composed of angular dicarboxylate SDB (4,4'-sulfonyldibenzoate) and N-donor BITMB (1,3-bis(imidazol-1-ylmethyl)-2,4,6-trimethyl benzene) have been synthesized by solvothermal reactions and characterized by single crystal X-ray diffraction and other physico-chemical techniques. CP1 possesses one-dimensional ribbon type metal–organic motifs glued together by H-bonds and π⋯π interactions, whereas CP2–CP4, exhibit non-interpenetrated sql networks supported by weak supramolecular interactions. Structural diversity of these CPs can be attributed to the coordination geometry adopted by the metal nodes,more » versatile coordination modes of SDB and conformational flexibility of BITMB. Solid state luminescence properties of CP1–CP4 were explored. Photocatalytic performance of all CPs for the decomposition of metanil yellow by dilute hydrogen peroxide in the presence of visible light was also investigated. 25–83% dye removal from aqueous solutions in the presence of CP1–CP4 was observed. - Graphical abstract: Four new ternary transition metal CPs have been hydrothermally prepared and their structural aspects as well as photocatalytic activity for decolourization of metanil yellow (MY) dye have been investigated. - Highlights: • Four ternary coordination polymers containing Ni, Cd, Zn and Co center are prepared. • Crystal structure and thermal stability of all four CPs has been described. • PL and diffuse reflectance spectra of synthesized CPs have also been examined. • Band gap values suggest semiconducting behavior of prepared CPs. • Photocatalytic activity of CPs for oxidative degradation of metanil yellow is studied.« less

Establishment and characterization of the reversibly immortalized mouse fetal heart progenitors.

PubMed

Li, Mi; Chen, Yuan; Bi, Yang; Jiang, Wei; Luo, Qing; He, Yun; Su, Yuxi; Liu, Xing; Cui, Jing; Zhang, Wenwen; Li, Ruidong; Kong, Yuhan; Zhang, Jiye; Wang, Jinhua; Zhang, Hongyu; Shui, Wei; Wu, Ningning; Zhu, Jing; Tian, Jie; Yi, Qi-Jian; Luu, Hue H; Haydon, Rex C; He, Tong-Chuan; Zhu, Gao-Hui

2013-01-01

Progenitor cell-based cardiomyocyte regeneration holds great promise of repairing an injured heart. Although cardiomyogenic differentiation has been reported for a variety of progenitor cell types, the biological factors that regulate effective cardiomyogenesis remain largely undefined. Primary cardiomyogenic progenitors (CPs) have a limited life span in culture, hampering the CPs' in vitro and in vivo studies. The objective of this study is to investigate if primary CPs isolated from fetal mouse heart can be reversibly immortalized with SV40 large T and maintain long-term cell proliferation without compromising cardiomyogenic differentiation potential. Primary cardiomyocytes were isolated from mouse E15.5 fetal heart, and immortalized retrovirally with the expression of SV40 large T antigen flanked with loxP sites. Expression of cardiomyogenic markers were determined by quantitative RT-PCR and immunofluorescence staining. The immortalization phenotype was reversed by using an adenovirus-mediated expression of the Cre reconbinase. Cardiomyogenic differentiation induced by retinoids or dexamethasone was assessed by an α-myosin heavy chain (MyHC) promoter-driven reporter. We demonstrate that the CPs derived from mouse E15.5 fetal heart can be efficiently immortalized by SV40 T antigen. The conditionally immortalized CPs (iCP15 clones) exhibit an increased proliferative activity and are able to maintain long-term proliferation, which can be reversed by Cre recombinase. The iCP15 cells express cardiomyogenic markers and retain differentiation potential as they can undergo terminal differentiate into cardiomyctes under appropriate differentiation conditions although the iCP15 clones represent a large repertoire of CPs at various differentiation stages. The removal of SV40 large T increases the iCPs' differentiation potential. Thus, the iCPs not only maintain long-term cell proliferative activity but also retain cardiomyogenic differentiation potential. Our results suggest that the reported reversible SV40 T antigen-mediated immortalization represents an efficient approach for establishing long-term culture of primary cardiomyogenic progenitors for basic and translational research.

A Quasi-Experimental Analysis of the Influence of Neighborhood Disadvantage on Child and Adolescent Conduct Problems

PubMed Central

Goodnight, Jackson A.; Lahey, Benjamin B.; Van Hulle, Carol A.; Rodgers, Joseph L.; Rathouz, Paul J.; Waldman, Irwin D.; D’Onofrio, Brian M.

2012-01-01

A quasi-experimental comparison of cousins differentially exposed to levels of neighborhood disadvantage (ND) was used with extensive measured covariates to test the hypothesis that neighborhood risk has independent effects on youth conduct problems (CPs). Multilevel analyses were based on mother-rated ND and both mother-reported CPs across 4–13 years (n = 7,077) and youth-reported CPs across 10–13 years (n = 4,524) from the Children of the National Longitudinal Survey of Youth. ND was robustly related to CPs reported by both informants when controlling for both measured risk factors that are correlated with ND and unmeasured confounds. These findings are consistent with the hypothesis that ND has influence on conduct problems. PMID:21942334

Trichomonas vaginalis Cysteine Proteinases: Iron Response in Gene Expression and Proteolytic Activity

PubMed Central

Cárdenas-Guerra, Rosa Elena; Figueroa-Angulo, Elisa Elvira; Puente-Rivera, Jonathan; Zamudio-Prieto, Olga; Ortega-López, Jaime

2015-01-01

We focus on the iron response of Trichomonas vaginalis to gene family products such as the cysteine proteinases (CPs) involved in virulence properties. In particular, we examined the effect of iron on the gene expression regulation and function of cathepsin L-like and asparaginyl endopeptidase-like CPs as virulence factors. We addressed some important aspects about CPs genomic organization and we offer possible explanations to the fact that only few members of this large gene family are expressed at the RNA and protein levels and the way to control their proteolytic activity. We also summarized all known iron regulations of CPs at transcriptional, posttranscriptional, and posttranslational levels along with new insights into the possible epigenetic and miRNA processes. PMID:26090464

A Systematic Review of Community Interventions to Improve Aboriginal Child Passenger Safety

PubMed Central

Oudie, Eugenia; Desapriya, Ediriweera; Turcotte, Kate; Pike, Ian

2014-01-01

We evaluated evidence of community interventions to improve Aboriginal child passenger safety (CPS) in terms of its scientific merit and cultural relevance. We included studies if they reported interventions to improve CPS in Aboriginal communities, compared at least pre- and postintervention conditions, and evaluated rates and severity of child passenger injuries, child restraint use, or knowledge of CPS. We also appraised quality and cultural relevance of studies. Study quality was associated with community participation and cultural relevance. Strong evidence showed that multicomponent interventions tailored to each community improves CPS. Interventions in Aboriginal communities should incorporate Aboriginal views of health, involve the community, and be multicomponent and tailored to the community’s circumstances and culture. PMID:24754652

Urea cycle regulation by mitochondrial sirtuin, SIRT5.

PubMed

Nakagawa, Takashi; Guarente, Leonard

2009-06-29

Mammalian sirtuins have diverse roles in aging, metabolism and disease. Recently we reported a new function for SIRT5 in urea cycle regulation. Our study uncovered that SIRT5 localized to mitochondria matrix and deacetylates carbamoyl phosphate synthetase 1 (CPS1), an enzyme which is the first and rate-limiting step of urea cycle. Deacetylation of CPS1 by SIRT5 resulted in activation of CPS1 enzymatic activity. Indeed, SIRT5-deficient mice failed to up-regulate CPS1 activity and showed hyper ammonemia during fasting. Similar effects are also observed on high protein diet or calorie restriction. These data indicate SIRT5 also has an emerging role in the metabolic adaptation to fasting, high protein diet and calorie restriction.

Assessment of potential factors associating with costs of hospitalizing cardiovascular diseases in 141 hospitals in Guangxi, China

PubMed Central

Zhou, Li-fang; Zhang, Mao-xin; Kong, Ling-qian; Liu, Jun-jun; Feng, Qi-ming; Lu, Wei; Wei, Bo; Zhao, Lue Ping

2017-01-01

Background The rising cost of healthcare is of great concern in China, as evidenced by the media features negative reports almost daily. However there are only a few studies from well-developed cities, like Beijing or Shanghai, and little is known about healthcare costs in rest of the country. In this study, we use hospitalization summary reports (HSRs) from admitted cardiovascular diseases patients in Guangxi hospitals during 2013–2016, and we investigate temporal trends of healthcare costs and associated factors. Methods By generalized additive model, we compute temporal trends of cost per stay (CPS), cost per day (CPD) and others. We then use generalized linear models to assess which factors associate with CPS and CPD. Findings Using a total of 760,000 HSRs, we find that CPS appears to be stabilized around $1040 until the middle of year 2015, before exhibiting a downward trend. Similarly, CPD exhibits similar stable pattern. Meanwhile, surgery-specific CPS showed an increase in year 2013–2014, and then stabilized. Drug costs account for over 1/3 of CPS, but they are gradually declining. Costs associated with physicians’ and nurses’ services represent less than 5% of CPS. We found that age, sex, marital status, occupation and payment methods are significantly associated with CPS or CPD. Interestingly, we found no association between patient ethnicity and these costs. However, we did find that minority patients use more secondary hospitals than Han patients. Interpretations Healthcare costs in Guangxi are stable, contrary to the rise portrayed by Chinese mass media. Several factors can be associated with healthcare costs, and these may be useful for developing evidence-based policies. In particular, there is a need to encourage more Han patients to seek care in primary and secondary hospitals. PMID:28301501

Utility of the CPS+EG staging system in hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer treated with neoadjuvant chemotherapy.

PubMed

Marmé, Frederik; Lederer, Bianca; Blohmer, Jens-Uwe; Costa, Serban Dan; Denkert, Carsten; Eidtmann, Holger; Gerber, Bernd; Hanusch, Claus; Hilfrich, Jörn; Huober, Jens; Jackisch, Christian; Kümmel, Sherko; Loibl, Sibylle; Paepke, Stefan; Untch, Michael; von Minckwitz, Gunter; Schneeweiss, Andreas

2016-01-01

Pathologic complete response after neoadjuvant chemotherapy (NACT) correlates with overall survival (OS) in primary breast cancer. A recently described staging system based on pre-treatment clinical stage (CS), final pathological stage (PS), estrogen receptor (ER) status and nuclear grade (NG) leads to a refined estimation of prognosis in unselected patients. Its performance in luminal type breast cancers has not been determined. This study investigates the clinical utility of this CPS+EG score when restricted to hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) patients and compares the results to a cohort of unselected patients. The CPS+EG score was calculated for 6637 unselected patients and 2454 patients with HR+/HER2- tumours who received anthracycline/taxane-based NACT within 8 prospective German trials. Five-year disease-free survival (DFS) and OS were 75.6% and 84.1% for the unselected cohort and 80.6% and 87.8% for the HR+/HER2- subgroup, respectively. The CPS+EG system distinguished different prognostic groups with 5-year DFS ranging from 0% to 91%. The CPS+EG system leads to an improved categorisation of patients by outcome compared to CS, PS, ER or NG alone. When applying the CPS+EG score to the HR+/HER2- subgroup, a shift to lower scores was observed compared to the overall population, but 5-year DFS and OS for the individual scores were identical to that observed in the overall population. In HR+/HER2- patients, the CPS+EG staging system retains its ability to facilitate a refined stratification of patients according to outcome. It can help to select candidates for post-neoadjuvant clinical trials in luminal breast cancer. Copyright © 2015 Elsevier Ltd. All rights reserved.

Protection against Streptococcus suis Serotype 2 Infection Using a Capsular Polysaccharide Glycoconjugate Vaccine

PubMed Central

Calzas, Cynthia; Shiao, Tze Chieh; Neubauer, Axel; Kempker, Jennifer; Roy, René; Gottschalk, Marcelo

2016-01-01

Streptococcus suis serotype 2 is an encapsulated bacterium and one of the most important bacterial pathogens in the porcine industry. Despite decades of research for an efficient vaccine, none is currently available. Based on the success achieved with other encapsulated pathogens, a glycoconjugate vaccine strategy was selected to elicit opsonizing anti-capsular polysaccharide (anti-CPS) IgG antibodies. In this work, glycoconjugate prototypes were prepared by coupling S. suis type 2 CPS to tetanus toxoid, and the immunological features of the postconjugation preparations were evaluated in vivo. In mice, experiments evaluating three different adjuvants showed that CpG oligodeoxyribonucleotide (ODN) induces very low levels of anti-CPS IgM antibodies, while the emulsifying adjuvants Stimune and TiterMax Gold both induced high levels of IgGs and IgM. Dose-response trials comparing free CPS with the conjugate vaccine showed that free CPS is nonimmunogenic independently of the dose used, while 25 μg of the conjugate preparation was optimal in inducing high levels of anti-CPS IgGs postboost. With an opsonophagocytosis assay using murine whole blood, sera from immunized mice showed functional activity. Finally, the conjugate vaccine showed immunogenicity and induced protection in a swine challenge model. When conjugated and administered with emulsifying adjuvants, S. suis type 2 CPS is able to induce potent IgM and isotype-switched IgGs in mice and pigs, yielding functional activity in vitro and protection against a lethal challenge in vivo, all features of a T cell-dependent response. This study represents a proof of concept for the potential of glycoconjugate vaccines in veterinary medicine applications against invasive bacterial infections. PMID:27113360

What is the number of child prostitutes in Thailand?

PubMed

Archavanitkul, K

1999-01-01

This study estimates the number of child prostitutes (CPs) in Thailand. It is estimated by Mahidol University that CPs amounted to about 36,000 children out of 150,000-200,000 prostitutes. The Center for the Protection of Children's Rights estimates that Thai and foreign child prostitutes aged under 11 years, in 1996, amounted to about 800,000 out of a total 2 million prostitutes. An estimated 20,000 establishments employed about 700,000 sex workers. About 30,000 underground sex establishments registered about 1.3 million sex workers. The Ministry of Public Health estimates that CPs amounted to about 16,276 in 1995. The 3 different estimates vary widely. This study estimates the number of CPs aged under 18 years of age, differentiates between Thai and foreign prostitutes, and accounts for those who entered prostitution prior to the age of 18 years. 16% of the total number of prostitutes may be Thai CPs; 50% may have begun their work under the age of 18. About 30% of total foreign prostitutes may be children; 75% may have entered prostitution as minors. A 1997 census of establishments indicates 7816 sex establishments. Based on field research on underestimation, it is estimated that 18,248 were foreign sex workers in Thailand in 1997, or 20% of the total of 90,915 sex workers. 90% of the foreign sex workers were estimated to be from the Mekong subregion of Myanmar, Laos, Cambodia, and Viet Nam. An estimated 4927 (30%) were CPs. During 1990-97, an estimated minimum 80,000 children and women from the Mekong subregion entered the sex trade. An estimated 18,000 were Thai CPs.

Transformation of chlorinated paraffins to olefins during metal work and thermal exposure - Deconvolution of mass spectra and kinetics.

PubMed

Schinkel, Lena; Lehner, Sandro; Knobloch, Marco; Lienemann, Peter; Bogdal, Christian; McNeill, Kristopher; Heeb, Norbert V

2018-03-01

Chlorinated paraffins (CPs) are high production volume chemicals widely used as additives in metal working fluids. Thereby, CPs are exposed to hot metal surfaces which may induce degradation processes. We hypothesized that the elimination of hydrochloric acid would transform CPs into chlorinated olefins (COs). Mass spectrometry is widely used to detect CPs, mostly in the selected ion monitoring mode (SIM) evaluating 2-3 ions at mass resolutions R < 20'000. This approach is not suited to detected COs, because their mass spectra strongly overlap with CPs. We applied a mathematical deconvolution method based on full-scan MS data to separate interfered CP/CO spectra. Metal drilling indeed induced HCl-losses. CO proportions in exposed mixtures of chlorotridecanes increased. Thermal exposure of chlorotridecanes at 160, 180, 200 and 220 °C also induced dehydrohalogenation reactions and CO proportions also increased. Deconvolution of respective mass spectra is needed to study the CP transformation kinetics without bias from CO interferences. Apparent first-order rate constants (k app ) increased up to 0.17, 0.29 and 0.46 h -1 for penta-, hexa- and heptachloro-tridecanes exposed at 220 °C. Respective half-life times (τ 1/2 ) decreased from 4.0 to 2.4 and 1.5 h. Thus, higher chlorinated paraffins degrade faster than lower chlorinated ones. In conclusion, exposure of CPs during metal drilling and thermal treatment induced HCl losses and CO formation. It is expected that CPs and COs are co-released from such processes. Full-scan mass spectra and subsequent deconvolution of interfered signals is a promising approach to tackle the CP/CO problem, in case of insufficient mass resolution. Copyright © 2017 Elsevier Ltd. All rights reserved.

Japan Meteorological Agency/Meteorological Research Institute-Coupled Prediction System version 1 (JMA/MRI-CPS1) for operational seasonal forecasting

NASA Astrophysics Data System (ADS)

Takaya, Yuhei; Yasuda, Tamaki; Fujii, Yosuke; Matsumoto, Satoshi; Soga, Taizo; Mori, Hirotoshi; Hirai, Masayuki; Ishikawa, Ichiro; Sato, Hitoshi; Shimpo, Akihiko; Kamachi, Masafumi; Ose, Tomoaki

2017-01-01

This paper describes the operational seasonal prediction system of the Japan Meteorological Agency (JMA), the Japan Meteorological Agency/Meteorological Research Institute-Coupled Prediction System version 1 (JMA/MRI-CPS1), which was in operation at JMA during the period between February 2010 and May 2015. The predictive skill of the system was assessed with a set of retrospective seasonal predictions (reforecasts) covering 30 years (1981-2010). JMA/MRI-CPS1 showed reasonable predictive skill for the El Niño-Southern Oscillation, comparable to the skills of other state-of-the-art systems. The one-tiered approach adopted in JMA/MRI-CPS1 improved its overall predictive skills for atmospheric predictions over those of the two-tiered approach of the previous uncoupled system. For 3-month predictions with a 1-month lead, JMA/MRI-CPS1 showed statistically significant skills in predicting 500-hPa geopotential height and 2-m temperature in East Asia in most seasons; thus, it is capable of providing skillful seasonal predictions for that region. Furthermore, JMA/MRI-CPS1 was superior overall to the previous system for atmospheric predictions with longer (4-month) lead times. In particular, JMA/MRI-CPS1 was much better able to predict the Asian Summer Monsoon than the previous two-tiered system. This enhanced performance was attributed to the system's ability to represent atmosphere-ocean coupled variability over the Indian Ocean and the western North Pacific from boreal winter to summer following winter El Niño events, which in turn influences the East Asian summer climate through the Pacific-Japan teleconnection pattern. These substantial improvements obtained by using an atmosphere-ocean coupled general circulation model underpin its success in providing more skillful seasonal forecasts on an operational basis.

Application of a VLSI vector quantization processor to real-time speech coding

NASA Technical Reports Server (NTRS)

Davidson, G.; Gersho, A.

1986-01-01

Attention is given to a working vector quantization processor for speech coding that is based on a first-generation VLSI chip which efficiently performs the pattern-matching operation needed for the codebook search process (CPS). Using this chip, the CPS architecture has been successfully incorporated into a compact, single-board Vector PCM implementation operating at 7-18 kbits/sec. A real time Adaptive Vector Predictive Coder system using the CPS has also been implemented.

Design of Cyclic Peptide Based Glucose Receptors and Their Application in Glucose Sensing.

PubMed

Li, Chao; Chen, Xin; Zhang, Fuyuan; He, Xingxing; Fang, Guozhen; Liu, Jifeng; Wang, Shuo

2017-10-03

Glucose assay is of great scientific significance in clinical diagnostics and bioprocess monitoring, and to design a new glucose receptor is necessary for the development of more sensitive, selective, and robust glucose detection techniques. Herein, a series of cyclic peptide (CP) glucose receptors were designed to mimic the binding sites of glucose binding protein (GBP), and CPs' sequence contained amino acid sites Asp, Asn, His, Asp, and Arg, which constituted the first layer interactions of GBP. The properties of these CPs used as a glucose receptor or substitute for the GBP were studied by using a quartz crystal microbalance (QCM) technique. It was found that CPs can form a self-assembled monolayer at the Au quartz electrode surface, and the monolayer's properties were characterized by using cyclic voltammetry, electrochemical impedance spectroscopy, and atomic force microscopy. The CPs' binding affinity to saccharide (i.e., galactose, fructose, lactose, sucrose, and maltose) was investigated, and the CPs' sensitivity and selectivity toward glucose were found to be dependent upon the configuration,i.e., the amino acids sequence of the CPs. The cyclic unit with a cyclo[-CNDNHCRDNDC-] sequence gave the highest selectivity and sensitivity for glucose sensing. This work suggests that a synthetic peptide bearing a particular functional sequence could be applied for developing a new generation of glucose receptors and would find huge application in biological, life science, and clinical diagnostics fields.

Cold Incineration of Chlorophenols in Aqueous Solution by Advanced Electrochemical Process Electro-Fenton. Effect of Number and Position of Chlorine Atoms on the Degradation Kinetics

NASA Astrophysics Data System (ADS)

Oturan, Nihal; Panizza, Marco; Oturan, Mehmet A.

2009-09-01

This study reports the kinetics of the degradation of several chlorophenols (CPs), such as monochlorophenols (2-chlorophenol and 4-chlorophenol), dichlorophenols (2,4-dichlorophenol and 2,6- dichlorophenol), trichlorophenols (2,3,5- trichlorophenol and 2,4,5-trichlorophenol), 2,3,5,6-tetrachlorophenol, and pentachlorophenol, by the electro-Fenton process using a carbon felt cathode and a Pt anode. The effect of number and the position of the chlorine atoms in the aromatic ring on the oxidative degradation rate was evaluated and discussed. The oxidation reaction of all the CPs with hydroxyl radicals evidenced a pseudo-first-order kinetics and the rate constant decreased with increasing the number of chlorine atoms. The absolute rate constant of second-order reaction kinetics between CPs and •OH was determined by the competition kinetics method in the range of (3.56-7.75) × 109 M-1 s-1 and follows the same sequence of the apparent rate constants. The mineralization of several CPs and of a mixture of all CPs under study was monitored by the total organic carbon (TOC) removal and the chlorine release during mineralization was followed by ion chromatography. Our results demonstrated that more chlorinated phenols are more difficult to mineralize; however for all the tested CPs, almost quantitative release of chloride ions was obtained after 6 h of treatment.

The Classroom Performance System (CPS): Effects on student participation, attendance, and achievement in multicultural anatomy and physiology classes at South Texas College

NASA Astrophysics Data System (ADS)

Termos, Mohamad Hani

2011-12-01

The Classroom Performance System (CPS) is an instructional technology tool that increases student performance and addresses different learning styles. Instructional technologies are used to promote active learning; however, student embarrassment issue in a multicultural setting is not addressed. This study assessed the effect of the CPS on student participation, attendance, and achievement in multicultural college-level anatomy and physiology classes at South Texas College, where the first spoken language is not English. Quantitative method and quasi-experimental design were employed and comparative statistic methods and pre-post tests were used to collect the data. Participants were college students and sections of study were selected by convenient sampling. Participation was 100% during most of the lectures held and participation rate did not strike above 68% in control group. Attendance was significantly higher in CPS sections than the control group as shown by t-tests. Experimental sections had a higher increase in the pre-post test scores and student averages on lecture exams increased at a higher rate as compared to the control group. Therefore, the CPS increased student participation, attendance, and achievement in multicultural anatomy and physiology classes. The CPS can be studied in other settings where the first spoken language is English or in other programs, such as special education programs. Additionally, other variables can be studied and other methodologies can be employed.

Streptococcus suis capsular polysaccharide inhibits phagocytosis through destabilization of lipid microdomains and prevents lactosylceramide-dependent recognition.

PubMed

Houde, Mathieu; Gottschalk, Marcelo; Gagnon, Fleur; Van Calsteren, Marie-Rose; Segura, Mariela

2012-02-01

Streptococcus suis type 2 is a major swine pathogen and a zoonotic agent, causing meningitis in both swine and humans. S. suis infects the host through the respiratory route, reaches the bloodstream, and persists until breaching into the central nervous system. The capsular polysaccharide (CPS) of S. suis type 2 is considered a key virulence factor of the bacteria. Though CPS allows S. suis to adhere to the membrane of cells of the immune system, it provides protection against phagocytosis. In fact, nonencapsulated mutants are easily internalized and killed by macrophages and dendritic cells. The objective of this work was to study the molecular mechanisms by which the CPS of S. suis prevents phagocytosis. By using latex beads covalently linked with purified CPS, it was shown that CPS itself was sufficient to inhibit entry of both latex beads and bystander fluorescent beads into macrophages. Upon contact with macrophages, encapsulated S. suis was shown to destabilize lipid microdomains at the cell surface, to block nitric oxide (NO) production during infection, and to prevent lactosylceramide accumulation at the phagocytic cup during infection. In contrast, the nonencapsulated mutant was easily internalized via lipid rafts, in a filipin-sensitive manner, leading to lactosylceramide recruitment and strong NO production. This is the first report to identify a role for CPS in lipid microdomain stability and to recognize an interaction between S. suis and lactosylceramide in phagocytes.

Amplified fragment length polymorphism of Streptococcus suis strains correlates with their profile of virulence-associated genes and clinical background.

PubMed

Rehm, Thomas; Baums, Christoph G; Strommenger, Birgit; Beyerbach, Martin; Valentin-Weigand, Peter; Goethe, Ralph

2007-01-01

Amplified fragment length polymorphism (AFLP) typing was applied to 116 Streptococcus suis isolates with different clinical backgrounds (invasive/pneumonia/carrier/human) and with known profiles of virulence-associated genes (cps1, -2, -7 and -9, as well as mrp, epf and sly). A dendrogram was generated that allowed identification of two clusters (A and C) with different subclusters (A1, A2, C1 and C2) and two heterogeneous groups of strains (B and D). For comparison, three strains from each AFLP subcluster and group were subjected to multilocus sequence typing (MLST) analysis. The closest relationship and lowest diversity were found for patterns clustering within AFLP subcluster A1, which corresponded with sequence type (ST) complex 1. Strains within subcluster A1 were mainly invasive cps1 and mrp+ epf+ (or epf*) sly+ cps2+ strains of porcine or human origin. A new finding of this study was the clustering of invasive mrp* cps9 isolates within subcluster A2. MLST analysis suggested that A2 correlates with a single ST complex (ST87). In contrast to A1 and A2, subclusters C1 and C2 contained mainly pneumonia isolates of genotype cps7 or cps2 and epf- sly-. In conclusion, this study demonstrates that AFLP allows identification of clusters of S. suis strains with clinical relevance.

Are persistent early onset child conduct problems predicted by the trajectories and initial levels of discipline practices?

PubMed

Lorber, Michael F; Slep, Amy M Smith

2015-08-01

In the present investigation we focused on 2 broad sets of questions: Do parental overreactivity, laxness, and corporal punishment show evidence of normative change in early to middle childhood? Are persistently elevated child conduct problems (CPs) associated with deviations from normative changes in, as well as high initial levels of, discipline practices? Four hundred fifty-three couples with 3- to 7-year-old children were recruited via random digit dialing and studied at 3 annual assessments. Parents completed questionnaire measures of all study constructs. Normative declines were found in maternal corporal punishment and laxness. Maternal overreactivity showed a normative increase. For fathers, only corporal punishment showed evidence of a normative decline. The declines in mothers' corporal punishment and laxness, and in fathers' corporal punishment, exhibited little variability. In contrast, the trajectories of maternal overreactivity were significantly variable. High-increasing CPs were more common than low-stable CPs in families with greater increases in maternal overreactivity. High-increasing CPs were also more common in families with greater initial maternal overreactivity and corporal punishment. Yet in no case did discipline practices significantly distinguish children on high-increasing versus high-decreasing CPs trajectories. In tests of alternative models, child effects were found for all parenting variables, suggesting reciprocal causation. The findings are discussed relative to etiological models of CPs and implications for preventive intervention. (c) 2015 APA, all rights reserved).

Dispersion of Short- and Medium-Chain Chlorinated Paraffins (CPs) from a CP Production Plant to the Surrounding Surface Soils and Coniferous Leaves.

PubMed

Xu, Jiazhi; Gao, Yuan; Zhang, Haijun; Zhan, Faqiang; Chen, Jiping

2016-12-06

Chlorinated paraffin (CP) production is one important emission source for short- and medium-chain CPs (SCCPs and MCCPs) in the environment. In this study, 48 CP congener groups were measured in the surface soils and coniferous leaves collected from the inner and surrounding environment of a CP production plant that has been in operation for more than 30 years to investigate the dispersion and deposition behavior of SCCPs and MCCPs. The average concentrations of the sum of SCCPs and MCCPs in the in-plant coniferous leaves and surface soils were 4548.7 ng g -1 dry weight (dw) and 3481.8 ng g -1 dw, which were 2-fold and 10-fold higher than those in the surrounding environment, respectively. The Gaussian air pollution model explained the spatial distribution of CPs in the coniferous leaves, whereas the dispersion of CPs to the surrounding surface soils fits the Boltzmann equation well. Significant fractionation effect was observed for the atmospheric dispersion of CPs from the production plant. CP congener groups with higher octanol-air partitioning coefficients (K OA ) were more predominant in the in-plant environment, whereas the ones with lower K OA values had the elevated proportion in the surrounding environment. A radius of approximately 4 km from the CP production plant was influenced by the atmospheric dispersion and deposition of CPs.

Problem-Solving Phase Transitions During Team Collaboration.

PubMed

Wiltshire, Travis J; Butner, Jonathan E; Fiore, Stephen M

2018-01-01

Multiple theories of problem-solving hypothesize that there are distinct qualitative phases exhibited during effective problem-solving. However, limited research has attempted to identify when transitions between phases occur. We integrate theory on collaborative problem-solving (CPS) with dynamical systems theory suggesting that when a system is undergoing a phase transition it should exhibit a peak in entropy and that entropy levels should also relate to team performance. Communications from 40 teams that collaborated on a complex problem were coded for occurrence of problem-solving processes. We applied a sliding window entropy technique to each team's communications and specified criteria for (a) identifying data points that qualify as peaks and (b) determining which peaks were robust. We used multilevel modeling, and provide a qualitative example, to evaluate whether phases exhibit distinct distributions of communication processes. We also tested whether there was a relationship between entropy values at transition points and CPS performance. We found that a proportion of entropy peaks was robust and that the relative occurrence of communication codes varied significantly across phases. Peaks in entropy thus corresponded to qualitative shifts in teams' CPS communications, providing empirical evidence that teams exhibit phase transitions during CPS. Also, lower average levels of entropy at the phase transition points predicted better CPS performance. We specify future directions to improve understanding of phase transitions during CPS, and collaborative cognition, more broadly. Copyright © 2017 Cognitive Science Society, Inc.

Towards a Semantic Web of Things: A Hybrid Semantic Annotation, Extraction, and Reasoning Framework for Cyber-Physical System

PubMed Central

Wu, Zhenyu; Xu, Yuan; Yang, Yunong; Zhang, Chunhong; Zhu, Xinning; Ji, Yang

2017-01-01

Web of Things (WoT) facilitates the discovery and interoperability of Internet of Things (IoT) devices in a cyber-physical system (CPS). Moreover, a uniform knowledge representation of physical resources is quite necessary for further composition, collaboration, and decision-making process in CPS. Though several efforts have integrated semantics with WoT, such as knowledge engineering methods based on semantic sensor networks (SSN), it still could not represent the complex relationships between devices when dynamic composition and collaboration occur, and it totally depends on manual construction of a knowledge base with low scalability. In this paper, to addresses these limitations, we propose the semantic Web of Things (SWoT) framework for CPS (SWoT4CPS). SWoT4CPS provides a hybrid solution with both ontological engineering methods by extending SSN and machine learning methods based on an entity linking (EL) model. To testify to the feasibility and performance, we demonstrate the framework by implementing a temperature anomaly diagnosis and automatic control use case in a building automation system. Evaluation results on the EL method show that linking domain knowledge to DBpedia has a relative high accuracy and the time complexity is at a tolerant level. Advantages and disadvantages of SWoT4CPS with future work are also discussed. PMID:28230725

Improving parenting in families referred for child maltreatment: a randomized controlled trial examining effects of Project Support.

PubMed

Jouriles, Ernest N; McDonald, Renee; Rosenfield, David; Norwood, William D; Spiller, Laura; Stephens, Nanette; Corbitt-Shindler, Deborah; Ehrensaft, Miriam

2010-06-01

Project Support is an intervention designed to decrease coercive patterns of aggressive discipline and increase positive parenting. This research evaluates Project Support in a sample of families reported to Children's Protective Services (CPS) for allegations of physical abuse or neglect; 35 families with a child between 3- and 8-years-old participated. In all families, CPS allowed the children to remain in the family home while the family received services. Families were randomly assigned to receive either Project Support or services as usual, which were provided by CPS or CPS-contracted service providers. To evaluate intervention effects, a multimethod, multi-informant assessment strategy was used that included data from mothers' reports, direct observation of parents' behavior, and review of CPS records for re-referrals for child maltreatment. Families who received Project Support services showed greater decreases than families who received services as usual in the following areas: mothers' perceived inability to manage childrearing responsibilities, mothers' reports of harsh parenting, and observations of ineffective parenting practices. Only 5.9% of families in the Project Support condition had a subsequent referral to CPS for child maltreatment, compared with 27.7% of families in the comparison condition. The results suggest that Project Support may be a promising intervention for reducing child maltreatment among families in which it has occurred. (c) 2010 APA, all rights reserved.

Effects of mipafox, paraoxon, chlorpyrifos and its metabolite chlorpyrifos-oxon on the expression of biomarker genes of differentiation in D3 mouse embryonic stem cells.

PubMed

Sogorb, Miguel A; Fuster, Encarnación; Del Río, Eva; Estévez, Jorge; Vilanova, Eugenio

2016-11-25

Chlorpyrifos (CPS) is an organophosphorus compound (OP) capable of causing well-known cholinergic and delayed syndromes through the inhibition of acetylcholinesterase and Neuropathy Target Esterase (NTE), respectively. CPS is also able to induce neurodevelopmental toxicity in animals. NTE is codified by the Pnpla6 gene and plays a central role in differentiation and neurodifferentiation. We tested, in D3 mouse embryonic stem cells under differentiation, the effects of the NTE inhibition by the OPs mipafox, CPS and its main active metabolite chlorpyrifos-oxon (CPO) on the expression of genes Vegfa, Bcl2, Amot, Nes and Jun, previously reported to be under- or overexpressed after Pnpla6 silencing in this same cellular model. Mipafox did not significantly alter the expression of such genes at concentrations that significantly inhibited NTE. However, CPS and CPO at concentrations that caused NTE inhibition at similar levels to mipafox statistically and significantly altered the expression of most of these genes. Paraoxon (another OP with capability to inhibit esterases but not NTE) caused similar effects to CPS and CPO. These findings suggest that the molecular mechanism for the neurodevelopmental toxicity induced by CPS is not based on NTE inhibition, and that other unknown esterases might be potential targets of neurodevelopmental toxicity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Chlorinated paraffins wrapping of carbon nanotubes: A theoretical investigation

NASA Astrophysics Data System (ADS)

Ding, Qiuyue; Ding, Ning; Chen, Xiangfeng; Wu, Chi-Man Lawrence

2018-04-01

How nanomaterials interact with pollutants is the central for understanding their environmental behavior and practical application. In this work, molecular dynamics (MD) and density functional theoretical (DFT) methods were used to investigated the influence of carbon chain length, degree of chlorination, chain configuration, and chirality of chlorinated paraffin (CP) and diameter of single-walled carbon nanotubes (SWNTs) on the interaction between CPs and SWNTs. The simulation results demonstrated that CP chain length and chlorination degree played considerably important roles in determining interaction strength between SWNTs and CPs. The interaction energies increased with increasing chain length and chlorination degree. The chirality of SWNT exerted negligible influence on the interaction energy between SWNTs and CPs. On the contrary, interaction energy increased with increasing radius of SWNTs due to the surface curvatures. This result was rationalized by considering the decrease in SWNT curvature with increasing radius, which resulted in plane-like CNT wall. The negligible influence of CP chain configurations was attributed to relative flexibility of CP carbon chains, which can wrap on tubes through conformational changes with low-energy barriers. MD results indicated that CPs could adsorb on SWNT surface rapidly in aqueous environment. Charge transfer and electronic density results indicated that the interaction between CPs and SWNTs was physisorption in nature. This work provides fundamental information regarding SWNTs as sorbents for CPs extraction and adsorptive removal from environmental water system.

The Feasibility of a Web-Intervention for Military and Veteran Spouses Concerned about their Partner’s Alcohol Misuse

PubMed Central

Osilla, Karen Chan; Pedersen, Eric R.; Tolpadi, Anagha; Howard, Stefanie Stern; Phillips, Jessica L.; Gore, Kristie L.

2017-01-01

Concerned partners (CPs) of military service members and veterans with alcohol misuse can be an important catalyst for change. We adapted the Community Reinforcement and Family Training (CRAFT) intervention into a 4-session web-based intervention (WBI) called Partners Connect. The program aims to help the CP increase their own well-being, teach the CP how to manage his/her behavior (e.g., communication) toward their partner, and identify ways the CP can help their partner reduce drinking and seek treatment. We recruited CPs through social media, and then tested the feasibility and acceptance of the WBI by conducting qualitative interviews and post-WBI session surveys after their WBI sessions. CPs (n=12) spontaneously reported improvements in communication and more effective management of their partner’s drinking due to skills learned. They discussed how the online approach can help overcome barriers to seeking in-person help. This WBI fills an important gap in clinical services for military and veteran CPs and CPs in the general population who may not otherwise seek in-person counseling. PMID:28039559

Polysaccharides from bamboo shoots processing by-products: New insight into extraction and characterization.

PubMed

Chen, Guangjing; Chen, Kewei; Zhang, Renfeng; Chen, Xiaolong; Hu, Peng; Kan, Jianquan

2018-04-15

In this study, an efficient accelerated solvent extraction (ASE) technology was applied for rapid extraction of polysaccharides from the processing by-products of Chimonobambusa quadrangularis (CPS). The extraction yields, physicochemical characterization, and antioxidant activities of CPS obtained by ASE and hot water extraction (HWE) were further compared. A maximal ASE-CPS yield was obtained by optimized extraction conditions (temperature 126 °C, 2 cycles, and 22 min) using response surface methodology. The yield of polysaccharides from ASE (9.96% ± 0.39%) was significantly higher than that from HWE (7.16% ± 0.32%). Differences were found between ASE and HWE with the chemical composition, molecular weight distribution, rheological property, and antioxidant activities of the obtained polysaccharides, while the primary structure remained the same. ASE-CPS exhibited better chemical antioxidant activities in oxygen radical absorbance capacity (ORAC), reducing power, and DPPH and hydroxyl radical scavenging ability, whereas HWE-CPS displayed higher activity in metal chelating activity assay. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of extraction methods on the yield, chemical structure and anti-tumor activity of polysaccharides from Cordyceps gunnii mycelia.

PubMed

Zhu, Zhen-Yuan; Dong, Fengying; Liu, Xiaocui; Lv, Qian; YingYang; Liu, Fei; Chen, Ling; Wang, Tiantian; Wang, Zheng; Zhang, Yongmin

2016-04-20

This study was to investigate the effects of different extraction methods on the yield, chemical structure and antitumor activity of polysaccharides from Cordyceps gunnii (C. gunnii) mycelia. Five extraction methods were used to extract crude polysaccharides (CPS), which include room-temperature water extraction (RWE), hot-water extraction (HWE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE) and cellulase-assisted extraction (CAE). Then Sephadex G-100 was used for purification of CPS. As a result, the antitumor activities of CPS and PPS on S180 cells were evaluated. Five CPS and purified polysaccharides (PPS) were obtained. The yield of CPS by microwave-assisted extraction (CPSMAE) was the highest and its anti-tumor activity was the best and its macromolecular polysaccharide (3000-1000kDa) ratio was the largest. The PPS had the same monosaccharide composition, but their obvious difference was in the antitumor activity and the physicochemical characteristics, such as intrinsic viscosity, specific rotation, scanning electron microscopy and circular dichroism spectra. Copyright © 2015 Elsevier Ltd. All rights reserved.

Optimization of microwave-assisted enzymatic extraction of polysaccharides from the fruit of Schisandra chinensis Baill.

PubMed

Cheng, Zhenyu; Song, Haiyan; Yang, Yingjie; Liu, Yan; Liu, Zhigang; Hu, Haobin; Zhang, Yang

2015-05-01

A microwave-assisted enzymatic extraction (MAEE) method had been developed, which was optimized by response surface methodology (RSM) and orthogonal test design, to enhance the extraction of crude polysaccharides (CPS) from the fruit of Schisandra chinensis Baill. The optimum conditions were as follows: microwave irradiation time of 10 min, extraction pH of 4.21, extraction temperature of 47.58°C, extraction time of 3h and enzyme concentration of 1.5% (wt% of S. chinensis powder) for cellulase, papain and pectinase, respectively. Under these conditions, the extraction yield of CPS was 7.38 ± 0.21%, which was well in close agreement with the value predicted by the model. The three methods including heat-refluxing extraction (HRE), ultrasonic-assisted extraction (UAE) and enzyme-assisted extraction (EAE) for extracting CPS by RSM were further compared. Results indicated MAEE method had the highest extraction yields of CPS at lower temperature. It was indicated that the proposed approach in this study was a simple and efficient technique for extraction of CPS in S. chinensis Baill. Copyright © 2015 Elsevier B.V. All rights reserved.

Workplace discrimination and cancer.

PubMed

McKenna, Maureen A; Fabian, Ellen; Hurley, Jessica E; McMahon, Brian T; West, Steven L

2007-01-01

Data from the Equal Employment Opportunity Commission (EEOC) Integrated Mission System database were analyzed with specific reference to allegations of workplace discrimination filed by individuals with cancer under ADA Title One. These 6,832 allegations, filed between July 27, 1992 and September 30, 2003, were compared to 167,798 allegations from a general disability population on the following dimensions: type of workplace discrimination; demographic characteristics of the charging parties (CPs); the industry designation, location, and size of employers; and the outcome or resolution of EEOC investigations. Results showed allegations derived from CPs with cancer were more likely than those in the general disability population to include issues involving discharge, terms and conditions of employment, lay-off, wages, and demotion. Compared to the general disability group, CPs with cancer were more likely to be female, older, and White. Allegations derived from CPs with cancer were also more likely to be filed against smaller employers (15-100 workers) or those in service industries. Finally, the resolution of allegations by CPs with cancer were more likely to be meritorious than those filed from the general disability population; that is, actual discrimination is more likely to have occurred.

Solvent induced rapid modulation of micro/nano structures of metal carboxylates coordination polymers: mechanism and morphology dependent magnetism.

PubMed

Liu, Kun; Shen, Zhu-Rui; Li, Yue; Han, Song-De; Hu, Tong-Liang; Zhang, Da-Shuai; Bu, Xian-He; Ruan, Wen-Juan

2014-08-12

Rational modulation of morphology is very important for functional coordination polymers (CPs) micro/nanostructures, and new strategies are still desired to achieve this challenging target. Herein, organic solvents have been established as the capping agents for rapid modulating the growth of metal-carboxylates CPs in organic solvent/water mixtures at ambient conditions. Co-3,5-pyridinedicarboxylate (pydc) CPs was studied here as the example. During the reaction, the organic solvents exhibited three types of modulation effect: anisotropic growth, anisotropic growth/formation of new crystalline phase and the formation of new crystalline phase solely, which was due to the variation of their binding ability with metal cations. The following study revealed that the binding ability was critically affected by their functional groups and molecular size. Moreover, their modulation effect could be finely tuned by changing volume ratios of solvent mixtures. Furthermore, they could be applied for modulating other metal-carboxylates CPs: Co-1,3,5-benzenetricarboxylic (BTC), Zn-pydc and Eu-pydc etc. Additionally, the as-prepared Co-pydc CPs showed a fascinating morphology-dependent antiferromagnetic behavior.

Solvent induced rapid modulation of micro/nano structures of metal carboxylates coordination polymers: mechanism and morphology dependent magnetism

NASA Astrophysics Data System (ADS)

Liu, Kun; Shen, Zhu-Rui; Li, Yue; Han, Song-De; Hu, Tong-Liang; Zhang, Da-Shuai; Bu, Xian-He; Ruan, Wen-Juan

2014-08-01

Rational modulation of morphology is very important for functional coordination polymers (CPs) micro/nanostructures, and new strategies are still desired to achieve this challenging target. Herein, organic solvents have been established as the capping agents for rapid modulating the growth of metal-carboxylates CPs in organic solvent/water mixtures at ambient conditions. Co-3,5-pyridinedicarboxylate (pydc) CPs was studied here as the example. During the reaction, the organic solvents exhibited three types of modulation effect: anisotropic growth, anisotropic growth/formation of new crystalline phase and the formation of new crystalline phase solely, which was due to the variation of their binding ability with metal cations. The following study revealed that the binding ability was critically affected by their functional groups and molecular size. Moreover, their modulation effect could be finely tuned by changing volume ratios of solvent mixtures. Furthermore, they could be applied for modulating other metal-carboxylates CPs: Co-1,3,5-benzenetricarboxylic (BTC), Zn-pydc and Eu-pydc etc. Additionally, the as-prepared Co-pydc CPs showed a fascinating morphology-dependent antiferromagnetic behavior.

Solvent induced rapid modulation of micro/nano structures of metal carboxylates coordination polymers: mechanism and morphology dependent magnetism

PubMed Central

Liu, Kun; Shen, Zhu-Rui; Li, Yue; Han, Song-De; Hu, Tong-Liang; Zhang, Da-Shuai; Bu, Xian-He; Ruan, Wen-Juan

2014-01-01

Rational modulation of morphology is very important for functional coordination polymers (CPs) micro/nanostructures, and new strategies are still desired to achieve this challenging target. Herein, organic solvents have been established as the capping agents for rapid modulating the growth of metal-carboxylates CPs in organic solvent/water mixtures at ambient conditions. Co-3,5-pyridinedicarboxylate (pydc) CPs was studied here as the example. During the reaction, the organic solvents exhibited three types of modulation effect: anisotropic growth, anisotropic growth/formation of new crystalline phase and the formation of new crystalline phase solely, which was due to the variation of their binding ability with metal cations. The following study revealed that the binding ability was critically affected by their functional groups and molecular size. Moreover, their modulation effect could be finely tuned by changing volume ratios of solvent mixtures. Furthermore, they could be applied for modulating other metal-carboxylates CPs: Co-1,3,5-benzenetricarboxylic (BTC), Zn-pydc and Eu-pydc etc. Additionally, the as-prepared Co-pydc CPs showed a fascinating morphology-dependent antiferromagnetic behavior. PMID:25113225

Child Protective Services referrals in cases of sudden infant death: a 10-year, population-based analysis in San Diego County, California.

PubMed

Krous, Henry F; Haas, Elisabeth A; Manning, Julie M; Deeds, Anita; Silva, Patricia D; Chadwick, Amy E; Stanley, Christina

2006-08-01

The potential diagnostic significance of prior family referral to Child Protective Services (CPS) in cases of sudden infant death is unknown. Therefore, the authors retrospectively searched for CPS data for the 5-year referral history on all 533 families whose infants died suddenly from Sudden Infant Death Syndrome (SIDS), other natural diseases, accidents, or inflicted injuries and underwent postmortem examination by the medical examiner during a 10-year period. No family had more than one infant death. At least 27% of the families in each group had at least one CPS referral. The data suggest that a family's referral to CPS prior to their sudden death of their infant does not increase the likelihood that it was caused by inflicted injuries, and prior referral should not preclude a diagnosis of SIDS. The authors recommend future prospective studies that include refined exposure histories and that are large enough to have sufficient statistical power to compare family CPS referrals and outcomes in groups of infants who died suddenly with a matched group of living infants.

Maternal Intimate Partner Violence Victimization Before and During Pregnancy and Postbirth Child Welfare Contact: A Population-Based Assessment.

PubMed

Parrish, Jared W; Lanier, Paul; Newby-Kew, Abigail; Arvidson, Joshua; Shanahan, Meghan

2016-02-01

We conducted a population-based prospective cohort study to help elucidate the predictive relationship between a maternal prebirth self-reported history of intimate partner violence (IPV) and any postbirth reported allegation to Child Protective Services (CPS) by age 2. We linked data from the 2009-2010 Alaska Pregnancy Risk Assessment Monitoring System with CPS data through 2012. Among this cohort, we found that 8.0%w self-reported experiencing IPV 12 months prior or during pregnancy, and 8.0%w of the offspring experienced at least one CPS report of alleged maltreatment during the study period. The predictive relationship varied by maternal educational attainment. Among mothers with 12+ years education completed, the odds of a CPS report were 3.9 times compared to those with no IPV, while among mothers with <12 years education completed, no association was noted. These results suggest that for a subset of Alaskan families, maternal history of IPV is a strong independent predictor of future CPS contact. © The Author(s) 2015.

Immunisation of cattle with cysteine proteinases of Trypanosoma congolense: targetting the disease rather than the parasite.

PubMed

Authié, E; Boulangé, A; Muteti, D; Lalmanach, G; Gauthier, F; Musoke, A J

2001-11-01

In order to test the hypothesis that trypanosome cysteine proteinases (CPs) contribute to pathology of trypanosomosis, cattle were immunised with CP1 and/or CP2, the major CPs of Trypanosoma congolense, and subsequently challenged with T. congolense. Immunisation had no effect on the establishment of infection and the development of acute anaemia. However, immunised cattle, unlike control cattle, maintained or gained weight during infection. Their haematocrit and leukocyte counts showed a tendency to recovery after 2-3 months of infection. Cattle immunised with CP2 mounted early and prominent IgG responses to CPs and to the variable surface glycoprotein following challenge. Thus trypanosome CPs may play a role in anaemia and immunosuppression; conversely, anti-CP antibody may modulate the trypanosome-induced pathology.

Cryogenic Propulsion Stage (CPS) Configuration in Support of NASA's Multiple Design Reference Missions (DRMs)

NASA Technical Reports Server (NTRS)

Hanna, Stephen G.; Jones, David L.; Creech, Stephen D.; Lawrence, Thomas D.

2012-01-01

In support of the National Aeronautics and Space Administration's (NASA) Human Exploration and Operations Mission Directorate (HEOMD), the Space Launch System (SLS) is being designed for safe, affordable, and sustainable human and scientific exploration missions beyond Earth's or-bit (BEO). The SLS Team is tasked with developing a system capable of safely and repeatedly lofting a new fleet of spaceflight vehicles beyond Earth orbit. The Cryogenic Propulsion Stage (CPS) is a key enabler for evolving the SLS capability for BEO missions. This paper reports on the methodology and initial recommendations relative to the CPS, giving a brief retrospective of early studies on this promising propulsion hardware. This paper provides an overview of the requirements development and CPS configuration in support of NASA's multiple Design Reference Missions (DRMs).

High Assurance Control of Cyber-Physical Systems with Application to Unmanned Aircraft Systems

NASA Astrophysics Data System (ADS)

Kwon, Cheolhyeon

With recent progress in the networked embedded control technology, cyber attacks have become one of the major threats to Cyber-Physical Systems (CPSs) due to their close integration of physical processes, computational resources, and communication capabilities. While CPSs have various applications in both military and civilian uses, their on-board automation and communication afford significant advantages over a system without such abilities, but these benefits come at the cost of possible vulnerability to cyber attacks. Traditionally, most cyber security studies in CPSs are mainly based on the computer security perspective, focusing on issues such as the trustworthiness of data flow, without rigorously considering the system's physical processes such as real-time dynamic behaviors. While computer security components are key elements in the hardware/software layer, these methods alone are not sufficient for diagnosing the healthiness of the CPSs' physical behavior. In seeking to address this problem, this research work proposes a control theoretic perspective approach which can accurately represent the interactions between the physical behavior and the logical behavior (computing resources) of the CPS. Then a controls domain aspect is explored extending beyond just the logical process of the CPS to include the underlying physical behavior. This approach will allow the CPS whose physical operations are robust/resilient to the damage caused by cyber attacks, successfully complementing the existing CPS security architecture. It is important to note that traditional fault-tolerant/robust control methods could not be directly applicable to achieve resiliency against malicious cyber attacks which can be designed sophisticatedly to spoof the security/safety monitoring system (note this is different from common faults). Thus, security issues at this layer require different risk management to detect cyber attacks and mitigate their impact within the context of a unified physical and logical process model of the CPS. Specifically, three main tasks are discussed in this presentation: (i) we first investigate diverse granularity of the interactions inside the CPS and propose feasible cyber attack models to characterize the compromised behavior of the CPS with various measures, from its severity to detectability; (ii) based on this risk information, our approach to securing the CPS addresses both monitoring of and high assurance control design against cyber attacks by developing on-line safety assessment and mitigation algorithms; and (iii) by extending the developed theories and methods from a single CPS to multiple CPSs, we examine the security and safety of multi-CPS network that are strongly dependent on the network topology, cooperation protocols between individual CPSs, etc. The effectiveness of the analytical findings is demonstrated and validated with illustrative examples, especially unmanned aircraft system (UAS) applications.

The effect of water-containing electrolyte on lithium-sulfur batteries

NASA Astrophysics Data System (ADS)

Wu, Heng-Liang; Haasch, Richard T.; Perdue, Brian R.; Apblett, Christopher A.; Gewirth, Andrew A.

2017-11-01

Dissolved polysulfides, formed during Li-S battery operation, freely migrate and react with both the Li anode and the sulfur cathode. These soluble polysulfides shuttle between the anode and cathode - the so-called shuttle effect - resulting in an infinite recharge process and poor Columbic efficiency. In this study, water present as an additive in the Li-S battery electrolyte is found to reduce the shuttle effect in Li-S batteries. Batteries where water content was below 50 ppm exhibited a substantial shuttle effect and low charge capacity. Alternatively, addition of 250 ppm water led to stable charge/discharge behavior with high Coulombic efficiency. XPS results show that H2O addition results in the formation of solid electrolyte interphase (SEI) film with more LiOH on Li anode which protects the Li anode from the polysulfides. Batteries cycled without water result in a SEI film with more Li2CO3 likely formed by direct contact between the Li metal and the solvent. Intermediate quantities of H2O in the electrolyte result in high cycle efficiency for the first few cycles which then rapidly decays. This suggests that H2O is consumed during battery cycling, likely by interaction with freshly exposed Li metal formed during Li deposition.

Building better lithium-sulfur batteries: from LiNO3 to solid oxide catalyst

NASA Astrophysics Data System (ADS)

Ding, Ning; Zhou, Lan; Zhou, Changwei; Geng, Dongsheng; Yang, Jin; Chien, Sheau Wei; Liu, Zhaolin; Ng, Man-Fai; Yu, Aishui; Hor, T. S. Andy; Sullivan, Michael B.; Zong, Yun

2016-09-01

Lithium nitrate (LiNO3) is known as an important electrolyte additive in lithium-sulfur (Li-S) batteries. The prevailing understanding is that LiNO3 reacts with metallic lithium anode to form a passivation layer which suppresses redox shuttles of lithium polysulfides, enabling good rechargeability of Li-S batteries. However, this view is seeing more challenges in the recent studies, and above all, the inability of inhibiting polysulfide reduction on Li anode. A closely related issue is the progressive reduction of LiNO3 on Li anode which elevates internal resistance of the cell and compromises its cycling stability. Herein, we systematically investigated the function of LiNO3 in redox-shuttle suppression, and propose the suppression as a result of catalyzed oxidation of polysulfides to sulfur by nitrate anions on or in the proximity of the electrode surface upon cell charging. This hypothesis is supported by both density functional theory calculations and the nitrate anions-suppressed self-discharge rate in Li-S cells. The catalytic mechanism is further validated by the use of ruthenium oxide (RuO2, a good oxygen evolution catalyst) on cathode, which equips the LiNO3-free cell with higher capacity and improved capacity retention over 400 cycles.

A Novel Polar Copolymer Design as a Multi-Functional Binder for Strong Affinity of Polysulfides in Lithium-Sulfur Batteries

NASA Astrophysics Data System (ADS)

Jiao, Yu; Chen, Wei; Lei, Tianyu; Dai, Liping; Chen, Bo; Wu, Chunyang; Xiong, Jie

2017-03-01

High energy density, low cost and environmental friendliness are the advantages of lithium-sulfur (Li-S) battery which is regarded as a promising device for electrochemical energy storage systems. As one of the important ingredients in Li-S battery, the binder greatly affects the battery performance. However, the conventional binder has some drawbacks such as poor capability of absorbing hydrophilic lithium polysulfides, resulting in severe capacity decay. In this work, we reported a multi-functional polar binder (AHP) by polymerization of hexamethylene diisocyanate (HDI) with ethylenediamine (EDA) bearing a large amount of amino groups, which were successfully used in electrode preparation with commercial sulfur powder cathodes. The abundant amide groups of the binder endow the cathode with multidimensional chemical bonding interaction with sulfur species within the cathode to inhibit the shuttling effect of polysulfides, while the suitable ductility to buffer volume change. Utilizing these advantageous features, composite C/S cathodes based the binder displayed excellent capacity retention at 0.5 C, 1 C, 1.5 C, and 3 C over 200 cycles. Accompany with commercial binder, AHP may act as an alternative feedstock to open a promising approach for sulfur cathodes in rechargeable lithium battery to achieve commercial application.

Chloride-Reinforced Carbon Nanofiber Host as Effective Polysulfide Traps in Lithium-Sulfur Batteries.

PubMed

Fan, Lei; Zhuang, Houlong L; Zhang, Kaihang; Cooper, Valentino R; Li, Qi; Lu, Yingying

2016-12-01

Lithium-sulfur (Li-S) battery is one of the most promising alternatives for the current state-of-the-art lithium-ion batteries due to its high theoretical energy density and low production cost from the use of sulfur. However, the commercialization of Li-S batteries has been so far limited to the cyclability and the retention of active sulfur materials. Using co-electrospinning and physical vapor deposition procedures, we created a class of chloride-carbon nanofiber composites, and studied their effectiveness on polysulfides sequestration. By trapping sulfur reduction products in the modified cathode through both chemical and physical confinements, these chloride-coated cathodes are shown to remarkably suppress the polysulfide dissolution and shuttling between lithium and sulfur electrodes. From adsorption experiments and theoretical calculations, it is shown that not only the sulfide-adsorption effect but also the diffusivity in the vicinity of these chlorides materials plays an important role on the reversibility of sulfur-based cathode upon repeated cycles. Balancing the adsorption and diffusion effects of these nonconductive materials could lead to the enhanced cycling performance of an Li-S cell. Electrochemical analyses over hundreds of cycles indicate that cells containing indium chloride-modified carbon nanofiber outperform cells with other halogenated salts, delivering an average specific capacity of above 1200 mAh g -1 at 0.2 C.

Controllably Designed "Vice-Electrode" Interlayers Harvesting High Performance Lithium Sulfur Batteries.

PubMed

Hao, Youchen; Xiong, Dongbin; Liu, Wen; Fan, Linlin; Li, Dejun; Li, Xifei

2017-11-22

An interlayer has been regarded as a promising mediator to prolong the life span of lithium sulfur batteries because its excellent absorbability to soluble polysulfide efficiently hinders the shuttle effect. Herein, we designed various interlayers and understand the working mechanism of an interlayer for lithium sulfur batteries in detail. It was found that the electrochemical performance of a S electrode for an interlayer located in cathode side is superior to the pristine one without interlayers. Surprisingly, the performance of the S electrode for an interlayer located in anode side is poorer than that of pristine one. For comparison, glass fibers were also studied as a nonconductive interlayer for lithium sulfur batteries. Unlike the two interlayers above, these nonconductive interlayer did displays significant capacity fading because polysulfides were adsorbed onto insulated interlayer. Thus, the nonconductive interlayer function as a "dead zone" upon cycling. Based on our findings, it was for the first time proposed that a controllably optimized interlayer, with electrical conductivity as well as the absorbability of polysulfides, may function as a "vice-electrode" of the anode or cathode upon cycling. Therefore, the cathodic conductive interlayer can enhance lithium sulfur battery performance, and the anodic conductive interlayer may be helpful for the rational design of 3D networks for the protection of lithium metal.

Polysulfide-Scission Reagents for the Suppression of the Shuttle Effect in Lithium-Sulfur Batteries.

PubMed

Hua, Wuxing; Yang, Zhi; Nie, Huagui; Li, Zhongyu; Yang, Jizhang; Guo, Zeqing; Ruan, Chunping; Chen, Xi'an; Huang, Shaoming

2017-02-28

Lithium-sulfur batteries have become an appealing candidate for next-generation energy-storage technologies because of their low cost and high energy density. However, one of their major practical problems is the high solubility of long-chain lithium polysulfides and their infamous shuttle effect, which causes low Coulombic efficiency and sulfur loss. Here, we introduced a concept involving the dithiothreitol (DTT) assisted scission of polysulfides into lithium-sulfur system. Our designed porous carbon nanotube/S cathode coupling with a lightweight graphene/DTT interlayer (PCNTs-S@Gra/DTT) exhibited ultrahigh cycle-ability even at 5 C over 1100 cycles, with a capacity degradation rate of 0.036% per cycle. Additionally, the PCNTs-S@Gra/DTT electrode with a 3.51 mg cm -2 sulfur mass loading delivered a high initial areal capacity of 5.29 mAh cm -2 (1509 mAh g -1 ) at current density of 0.58 mA cm -2 , and the reversible areal capacity of the cell was maintained at 3.45 mAh cm -2 (984 mAh g -1 ) over 200 cycles at a higher current density of 1.17 mA cm -2 . Employing this molecule scission principle offers a promising avenue to achieve high-performance lithium-sulfur batteries.

Biomass derived Ni(OH)2@porous carbon/sulfur composites synthesized by a novel sulfur impregnation strategy based on supercritical CO2 technology for advanced Li-S batteries

NASA Astrophysics Data System (ADS)

Xia, Yang; Zhong, Haoyue; Fang, Ruyi; Liang, Chu; Xiao, Zhen; Huang, Hui; Gan, Yongping; Zhang, Jun; Tao, Xinyong; Zhang, Wenkui

2018-02-01

The rational design and controllable synthesis of sulfur cathode with high sulfur content, superior structural stability and fascinating electrochemical properties is a vital step to realize the large-scale application of rechargeable lithium-sulfur (Li-S) batteries. However, the electric insulation of elemental sulfur and the high solubility of lithium polysulfides are two intractable obstacles to hinder the success of Li-S batteries. In order to overcome aforementioned issues, a novel strategy combined supercritical CO2 fluid technology and biotemplating method is developed to fabricate Ni(OH)2 modified porous carbon microspheres as sulfur hosts to ameliorate the electronic conductive of sulfur and enhance simultaneously the physical and chemical absorptions of polysulfides. This elaborately designed Ni(OH)2@PYC/S composite cathode exhibits high reversible discharge capacity (1335 mAh g-1 at 0.1 C), remarkable cyclic stability (602 mAh g-1 after 200 cycles at 0.2 C) and superior rate capability, which is much better than its PYC/S counterpart. These results clearly demonstrate that the advanced porous carbon with good conductivity and the polar Ni(OH)2 coating layer with strong trapping ability of polysulfides are responsible for the enhanced electrochemical performance.

Atomic Iron Catalysis of Polysulfide Conversion in Lithium-Sulfur Batteries.

PubMed

Liu, Zhenzhen; Zhou, Lei; Ge, Qi; Chen, Renjie; Ni, Mei; Utetiwabo, Wellars; Zhang, Xiaoling; Yang, Wen

2018-06-13

Lithium-sulfur batteries have been regarded as promising candidates for energy storage because of their high energy density and low cost. It is a main challenge to develop long-term cycling stability battery. Here, a catalytic strategy is presented to accelerate reversible transformation of sulfur and its discharge products in lithium-sulfur batteries. This is achieved with single-atomic iron active sites in porous nitrogen-doped carbon, prepared by polymerizing and carbonizing diphenylamine in the presence of iron phthalocyanine and a hard template. The Fe-PNC/S composite electrode exhibited a high discharge capacity (427 mAh g -1 ) at a 0.1 C rate after 300 cycles with the Columbic efficiency of above 95.6%. Besides, the electrode delivers much higher capacity of 557.4 mAh g -1 at 0.5 C over 300 cycles. Importantly, the Fe-PCN/S has a smaller phase nucleation overpotential of polysulfides than nitrogen-doped carbon alone for the formation of nanoscale of Li 2 S as revealed by ex situ SEM, which enhance lithium-ion diffusion in Li 2 S, and therefore a high rate performance and remarkable cycle life of Li-sulfur batteries were achieved. Our strategy paves a new way for polysulfide conversion with atomic iron catalysis to exploit high-performance lithium-sulfur batteries.

A Nacre-Like Carbon Nanotube Sheet for High Performance Li-Polysulfide Batteries with High Sulfur Loading.

PubMed

Pan, Zheng-Ze; Lv, Wei; He, Yan-Bing; Zhao, Yan; Zhou, Guangmin; Dong, Liubing; Niu, Shuzhang; Zhang, Chen; Lyu, Ruiyang; Wang, Cong; Shi, Huifa; Zhang, Wenjie; Kang, Feiyu; Nishihara, Hirotomo; Yang, Quan-Hong

2018-06-01

Lithium-sulfur (Li-S) batteries are considered as one of the most promising energy storage systems for next-generation electric vehicles because of their high-energy density. However, the poor cyclic stability, especially at a high sulfur loading, is the major obstacles retarding their practical use. Inspired by the nacre structure of an abalone, a similar configuration consisting of layered carbon nanotube (CNT) matrix and compactly embedded sulfur is designed as the cathode for Li-S batteries, which are realized by a well-designed unidirectional freeze-drying approach. The compact and lamellar configuration with closely contacted neighboring CNT layers and the strong interaction between the highly conductive network and polysulfides have realized a high sulfur loading with significantly restrained polysulfide shuttling, resulting in a superior cyclic stability and an excellent rate performance for the produced Li-S batteries. Typically, with a sulfur loading of 5 mg cm -2 , the assembled batteries demonstrate discharge capacities of 1236 mAh g -1 at 0.1 C, 498 mAh g -1 at 2 C and moreover, when the sulfur loading is further increased to 10 mg cm -2 coupling with a carbon-coated separator, a superhigh areal capacity of 11.0 mAh cm -2 is achieved.

A self-cleaning Li-S battery enabled by a bifunctional redox mediator

NASA Astrophysics Data System (ADS)

Ren, Y. X.; Zhao, T. S.; Liu, M.; Zeng, Y. K.; Jiang, H. R.

2017-09-01

The polysulfide shuttle effect and lithium dendrite growth in lithium-sulfur (Li-S) batteries can repeatedly breach the anodic solid electrolyte interphase (SEI) over cycling. As a result, irreversible short-chain sulfide side products (Li2Sx, x = 1, 2) keep depositing on the Li anode, leading to the active material loss, increasing the Li+ transport resistance, and thereby reducing the cycle life. In this work, indium iodide (InI3) is investigated as a bifunctional electrolyte additive for Li-S batteries to protect the Li anode and decompose the side products spontaneously. On the one hand, Indium (In) is electrodeposited onto the Li anode prior to Li plating during the initial charging process, forming a chemically and mechanically stable SEI to prevent the Li anode from reacting with soluble polysulfide species to form Li2Sx (x = 1, 2) side products. On the other hand, by adequately overcharging the battery, the triiodide/iodide redox mediator is capable of chemically transforming side products deposited on the Li anode and separator into soluble polysulfides, which can be recycled by the cathode. It is shown that the battery with the InI3 additive exhibits a prolonged cycle life, and is capable of retrieving its capacity by a facile overcharging process.

Ionic Liquid-Enhanced Solid State Electrolyte Interface (SEI) for Lithium Sulfur Batteries

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

Zheng, Jianming; Gu, Meng; Chen, Honghao

2013-05-16

Li-S battery is a complicated system with many challenges existing before its final market penetration. While most of the reported work for Li-S batteries is focused on the cathode design, we demonstrate in this work that the anode consumption accelerated by corrosive polysulfide solution also critically determines the Li-S cell performance. To validate this hypothesis, ionic liquid (IL) N-methyl-N-butylpyrrolidinium bis(trifluoromethylsulfonyl)imide (Py14TFSI) has been employed to modify the properties of SEI layer formed on Li metal surface in Li-S batteries. It is found that the IL-enhanced passivation film on the lithium anode surface exhibits much different morphology and chemical compositions, effectivelymore » protecting lithium metal from continuous attack by soluble polysulfides. Therefore, both cell impedance and the irreversible consumption of polysulfides on lithium metal are reduced. As a result, the Coulombic efficiency and the cycling stability of Li-S batteries have been greatly improved. After 120 cycles, Li-S battery cycled in the electrolyte containing IL demonstrates a high capacity retention of 94.3% at 0.1 C rate. These results unveil another important failure mechanism for Li-S batteries and shin the light on the new approaches to improve Li-S battery performances.« less

The effect of co-solvent addition on Li-solvation in solvate electrolytes in Li-S batteries

NASA Astrophysics Data System (ADS)

Lau, Kah Chun; See, Kimberly A.; Wu, Heng-Liang; Shin, Minjeong; Curtiss, Larry A.; Gewirth, Andrew A.

Li?S batteries are a promising next-generation battery technology. Due to the formation of soluble polysulfides during cell operation, the electrolyte composition of the cell plays an active role in directing the formation and speciation of the soluble lithium polysulfides. Recently, new classes of electrolytes termed `solvates' that contain stoichiometric quantities of salt and solvent and form a liquid at room temperature have been explored due to their sparingly solvating properties with respect to polysulfides. The viscosity of the solvate electrolytes is understandably high limiting their viability, however, cosolvents that thought to be inert to the solvate structure itself, can be introduced to reduce viscosity and enhance diffusion. In this work, Raman and NMR spectroscopy coupled with ab initio molecular dynamics simulations are used to study the unique solvation structure of 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether as co-solvent in solvate (MeCN)2?LiTFSI electrolyte that used in Li-S battery. The underlying design rules and implications to Li-S battery performance will be discussed. This work was supported as part of the Joint Center for Energy Storage Research, an Energy Innovation Hub funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences.

Direct measurement of polysulfide shuttle current: A window into understanding the performance of lithium-sulfur cells

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

Moy, Derek; Manivannan, A.; Narayanan, S. R.

2014-11-04

The shuttling of polysulfide ions between the electrodes in a lithium-sulfur battery is a major technical issue limiting the self-discharge and cycle life of this high-energy rechargeable battery. Although there have been attempts to suppress the shuttling process, there has not been a direct measurement of the rate of shuttling. We report here a simple and direct measurement of the rate of the shuttling (that we term “shuttle current”), applicable to the study of any type of lithium-sulfur cell. We demonstrate the effectiveness of this measurement technique using cells with and without lithium nitrate (a widely-used shuttle suppressor additive). Wemore » present a phenomenological analysis of the shuttling process and simulate the shuttle currents as a function of the state-of-charge of a cell. We also demonstrate how the rate of decay of the shuttle current can be used to predict the capacity fade in a lithium-sulfur cell due to the shuttle process. As a result, we expect that this new ability to directly measure shuttle currents will provide greater insight into the performance differences observed with various additives and electrode modifications that are aimed at suppressing the rate of shuttling of polysulfide ions and increasing the cycle life of lithium-sulfur cells.« less

Building better lithium-sulfur batteries: from LiNO3 to solid oxide catalyst

PubMed Central

Ding, Ning; Zhou, Lan; Zhou, Changwei; Geng, Dongsheng; Yang, Jin; Chien, Sheau Wei; Liu, Zhaolin; Ng, Man-Fai; Yu, Aishui; Hor, T. S. Andy; Sullivan, Michael B.; Zong, Yun

2016-01-01

Lithium nitrate (LiNO3) is known as an important electrolyte additive in lithium-sulfur (Li-S) batteries. The prevailing understanding is that LiNO3 reacts with metallic lithium anode to form a passivation layer which suppresses redox shuttles of lithium polysulfides, enabling good rechargeability of Li-S batteries. However, this view is seeing more challenges in the recent studies, and above all, the inability of inhibiting polysulfide reduction on Li anode. A closely related issue is the progressive reduction of LiNO3 on Li anode which elevates internal resistance of the cell and compromises its cycling stability. Herein, we systematically investigated the function of LiNO3 in redox-shuttle suppression, and propose the suppression as a result of catalyzed oxidation of polysulfides to sulfur by nitrate anions on or in the proximity of the electrode surface upon cell charging. This hypothesis is supported by both density functional theory calculations and the nitrate anions-suppressed self-discharge rate in Li-S cells. The catalytic mechanism is further validated by the use of ruthenium oxide (RuO2, a good oxygen evolution catalyst) on cathode, which equips the LiNO3-free cell with higher capacity and improved capacity retention over 400 cycles. PMID:27629986

Co3O4-Carbon Cloth free standing cathode for lithium sulfur battery

NASA Astrophysics Data System (ADS)

Xu, Jing; Su, Dawei; Wang, Guoxiu

2017-07-01

Lithium-sulfur (Li-S) battery has been considered to be one of the most promising next-generation electrochemical energy-storage systems due to its high theoretical energy of 2600 Wh kg-1 with low cost. The insulating nature of both sulfur and the dissolution of polysulfides are the two primary challenges for the application of lithium sulfur batteries. Here, we developed a binder-free cathode by chemisorption of Co3O4 to carbon cloth (CC), which was used as a 3D current collector to accommodate a large amount of sulfur, multiwall carbon nanofiber (MWCNF) and carbon black (CB) hybrids within the conductive scaffold, enabling the fabrication of ultrahigh sulfur loaded electrodes. The interconnected carbon fibers established a long-range conductive matrix for an efficient electron transport, the multiple conductive pathways guarantee high sulfur utilization. More importantly, the high electrolyte absorbability of the Co3O4-CC-S current collector facilitates well-localized polysulfides within the Co3O4-CC-S, meanwhile, the polar Co3O4 could also effectively entrapped the intermediated polysulfides preventing their free diffusion to the lithium anode, guaranteeing good cycling stability. Consequently, the Co3O4-CC-S electrodes exhibit excellent electrochemical performance with sulfur loading of 4.3 mg cm-2.

Extending AADL for Security Design Assurance of Cyber Physical Systems

DTIC Science & Technology

2015-12-16

a detailed system architecture design of a CPS can be analyzed using AADL to prevent such types of CWEs. We divided the work into two tasks as...security modeling to CPSs, and develop a case study to show how formal modeling using AADL could be applied to a CPS to improve the security design of the... CPS . These examples of recent attacks against automobiles have been reported:  A wireless device used by Progressive Insurance to gather information

Level of Discomfort Decreases After the Administration of Continuous Palliative Sedation: A Prospective Multicenter Study in Hospices and Palliative Care Units.

PubMed

van Deijck, Rogier H P D; Hasselaar, Jeroen G J; Verhagen, Stans C A H H V M; Vissers, Kris C P; Koopmans, Raymond T C M

2016-09-01

A gold standard or validated tool for monitoring the level of discomfort during continuous palliative sedation (CPS) is lacking. Therefore, little is known about the course of discomfort in sedated patients, the efficacy of CPS, and the determinants of discomfort during CPS. To identify the course of discomfort in patients receiving CPS. A prospective observational multicenter study in nine hospices and palliative care units was performed. The Discomfort Scale-Dementia of Alzheimer Type (DS-DAT) was independently assessed for monitoring of patient discomfort during CPS. The DS-DAT scores range from 0 (no observed discomfort) to a maximum of 27 (high level of observed discomfort). Using a mixed model, the mean group score of discomfort between four predefined time frames of CPS was compared, correcting for confounding patient characteristics. A total of 130 patients were sedated, and the DS-DAT was completed in 106 patients at least once. The median duration of the sedation in these 106 patients was 25.5 hours (range 2-161). The mean score of the DS-DAT in the phase before sedation was 12.16 (95% CI 9.83-14.50) and decreased significantly to 8.06 (95% CI 5.53-10.58) in the titration phase of sedation. The mean score of the DS-DAT in the final phase of sedation was 7.42 (95% CI 4.90-9.94). This study shows that CPS is associated with a decrease in the level of discomfort within an acceptable time frame, although in some sedated patients higher levels of discomfort in the last hours of life occurred. Although the DS-DAT seems to be of value for monitoring the level of discomfort during CPS, the results of this study should be interpreted within the constraints of the limitations, and further research on the psychometric properties of this tool is needed before the DS-DAT can be used in clinical practice. Copyright © 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Patient-Related Determinants of the Administration of Continuous Palliative Sedation in Hospices and Palliative Care Units: A Prospective, Multicenter, Observational Study.

PubMed

van Deijck, Rogier H P D; Hasselaar, Jeroen G J; Verhagen, Stans C A H H V M; Vissers, Kris C P; Koopmans, Raymond T C M

2016-05-01

Knowledge of determinants that are associated with the administration of continuous palliative sedation (CPS) helps physicians identify patients who are at risk of developing refractory symptoms, thereby enabling proactive care planning. This study aims to explore which patient-related factors at admission are associated with receiving CPS later in the terminal phase of life. A prospective multicenter observational study was performed in six Dutch hospices and three nursing home-based palliative care units. The association between patient-related variables at admission (age, gender, diagnosis, use of opioids or psycholeptics, number of medications, Karnofsky Performance Status scale score, Edmonton Symptom Assessment System distress score, and Glasgow Coma Scale score) and the administration of CPS at the end of life was analyzed. A total of 467 patients died during the study period, of whom 130 received CPS. In univariate analysis, statistically significant differences were noted between the sedated and nonsedated patients with respect to younger age (P = 0.009), malignancy as a diagnosis (P = 0.05), higher Karnofsky Performance Status score (P = 0.03), the use of opioids (P < 0.001), the use of psycholeptics (P = 0.003), and higher Edmonton Symptom Assessment System distress score (P = 0.05). Multivariate logistic regression analysis showed that only the use of opioids at admission (odds ratio 1.90; 95% confidence interval 1.18-3.05) was significantly associated with the administration of CPS. Physicians should be aware that patients who use opioids at admission have an increased risk for the administration of CPS at the end of life. In this group of patients, a comprehensive personalized care plan starting at admission is mandatory to try to prevent the development of refractory symptoms. Further research is recommended, to identify other determinants of the administration of CPS and to investigate which early interventions will be effective to prevent the need for CPS in patients at high risk. Copyright © 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Reversible synthesis of colanic acid and O-antigen polysaccharides in Salmonella Typhimurium enhances induction of cross-immune responses and provides protection against heterologous Salmonella challenge.

PubMed

Li, Pei; Liu, Qing; Huang, Chun; Zhao, Xinxin; Roland, Kenneth L; Kong, Qingke

2017-05-15

Colanic Acid (CA) and lipopolysaccharide (LPS) are two major mannose-containing extracellular polysaccharides of Salmonella. Their presence on the bacterial surface can mask conserved protective outer membrane proteins (OMPs) from the host immune system. The mannose moiety in these molecules is derived from GDP-mannose, which is synthesized in several steps. The first two steps require the action of phosphomannose isomerase, encoded by pmi (manA), followed by phosphomannomutase, encoded by manB. There are two copies of manB present in the Salmonella chromosome, one located in the cps gene cluster (cpsG) responsible for CA synthesis, and the other in the rfb gene cluster (rfbK) involved in LPS O-antigen synthesis. In this study, it was demonstrated that the products of cpsG and rfbK are isozymes. To evaluate the impact of these genes on O-antigen synthesis, virulence and immunogenicity, single mutations (Δpmi, ΔrfbK or ΔcpsG) and a double mutation (ΔrfbK ΔcpsG) were introduced into both wild-type Salmonella enterica and an attenuated Δcya Δcrp vaccine strain. The Δpmi, ΔrfbK and ΔcpsG ΔrfbK mutants were defective in LPS synthesis and attenuated for virulence. In orally inoculated mice, strain S122 (Δcrp Δcya ΔcpsG ΔrfbK) and its parent S738 (Δcrp Δcya) were both avirulent and colonized internal tissues. Strain S122 elicited higher levels of anti-S. Typhimurium OMP serum IgG than its parent strain. Mice immunized with S122 were completely protected against challenge with wild-type virulent S. Typhimurium and partially protected against challenge with either wild-type virulent S. Choleraesuis or S. Enteritidis. These data indicate that deletions in rfbK and cpsG are useful mutations for inclusion in future attenuated Salmonella vaccine strains to induce cross-protective immunity. Copyright © 2017 Elsevier Ltd. All rights reserved.

[Biomechanical study on effects of bone mineral density on fixation strength of expansive pedicle screw].

PubMed

Gao, Mingxuan; Li, Xusheng; Zhen, Ping; Wu, Zhigang; Zhou, Shenghu; Tian, Qi; Lei, Wei

2013-08-01

To evaluate the fixation strength of expansive pedicle screw (EPS) at different bone mineral density (BMD) levels, further to provide theoretical evidence for the clinical application of the EPS in patients with osteoporosis. Fresh human cadaver spines (T12-L5 spines) were divided into 4 levels: normal BMD, osteopenia, osteoporosis, and severe osteoporosis according to the value of BMD, 12 vertebra in each level. Conventional pedicle screw (CPS) or EPS was implanted into the bilateral vertebra in CPS group and EPS group, respectively, 12 screws in each group per BMD level. Screw pullout tests were conducted. The maximum pullout strength, stiffness, and energy absorption were determined by an AG-IS material testing machine with constant rate of loading in a speed of 5 mm/min. With the decline of BMD from normal to severe osteoporosis level, the maximum pullout strength and the stiffness correspondingly declined (P < 0.05). In CPS group, the energy absorption gradually decreased (P < 0.05); in EPS group, significant difference was found between other different BMD levels (P < 0.05) except between normal BMD and osteopenia and between osteoporosis and severe osteoporosis (P > 0.05). At the same BMD level, the maximum pullout strength of EPS group was significantly larger than that of CPS group (P < 0.05); the stiffness of EPS group was significantly higher than that of CPS group (P < 0.05) except one at normal BMD level; and no significant difference was found in the energy absorption between 2 groups (P > 0.05) except one at osteopenia level. No significant difference was found in maximum pullout strength, stiffness, and energy absorption between EPS group at osteoporosis level and CPS group at osteopenia level (P > 0.05); however, the maximum pullout strength, stiffness, and energy absorption of EPS group at severe osteoporosis level were significantly lower than those of CPS group at osteopenia level (P < 0.05). Compared with CPS, the EPS can significantly improve the fixation strength, especially in patients with osteopenia or osteoporosis.

Neighborhood collective efficacy, parental spanking, and subsequent risk of household child protective services involvement.

PubMed

Ma, Julie; Grogan-Kaylor, Andrew; Klein, Sacha

2018-06-01

Children exposed to negative neighborhood conditions and parental spanking are at higher risk of experiencing maltreatment. We conducted prospective analyses of secondary data to determine the effects of neighborhood collective efficacy and parental spanking on household Child Protective Services (CPS) involvement, and whether spanking mediates the relationship between neighborhood collective efficacy and CPS involvement. The sample (N = 2,267) was drawn from the Fragile Families and Child Wellbeing Study (FFCWS), a stratified random sample of 4,789 births between 1998-2000 in 20 large U.S. cities. Logistic regression models were employed to test the effects of neighborhood collective efficacy and spanking at child age 3 on mother's report of CPS contact during the subsequent two years. The product-of-coefficient approach was used to test the mediation hypothesis. One aspect of neighborhood collective efficacy (i.e., Social Cohesion/Trust) is associated with lower odds of CPS involvement (OR = .80, 95% CI 0.670-0.951) after controlling for Informal Social Control, parental spanking, and the covariates. Parental spanking predicts increased odds of CPS involvement during the next two years (OR = 1.38, 95% CI 1.001-1.898), net of neighborhood collective efficacy and the covariates. The mediation hypothesis is not supported. Promoting both cohesive and trusting relationships between neighbors and non-physical discipline practices is likely to reduce the incidence of household CPS involvement. Copyright © 2018 Elsevier Ltd. All rights reserved.

Providing patient care in community pharmacies in Australia.

PubMed

Benrimoj, Shalom I; Roberts, Alison S

2005-11-01

To describe Australia's community pharmacy network in the context of the health system and outline the provision of services. The 5000 community pharmacies form a key component of the healthcare system for Australians, for whom health expenditures represent 9% of the Gross Domestic Product. A typical community pharmacy dispenses 880 prescriptions per week. Pharmacists are key partners in the Government's National Medicines Policy and contribute to its objectives through the provision of cognitive pharmaceutical services (CPS). The Third Community Pharmacy Agreement included funding for CPS including medication review and the provision of written drug information. Funding is also provided for a quality assurance platform with which the majority of pharmacies are accredited. Fifteen million dollars (Australian) have been allocated to research in community pharmacy, which has focused on achieving quality use of medicines (QUM), as well as developing new CPS and facilitating change. Elements of the Agreements have taken into account QUM principles and are now significant drivers of practice change. Although accounting for 10% of remuneration for community pharmacy, the provision of CPS represents a significant shift in focus to view pharmacy as a service provider. Delivery of CPS through the community pharmacy network provides sustainability for primary health care due to improvement in quality presumably associated with a reduction in healthcare costs. Australian pharmacy practice is moving strongly in the direction of CPS provision; however, change does not occur easily. The development of a change management strategy is underway to improve the uptake of professional and business opportunities in community pharmacy.

Streptococcus suis Capsular Polysaccharide Inhibits Phagocytosis through Destabilization of Lipid Microdomains and Prevents Lactosylceramide-Dependent Recognition

PubMed Central

Houde, Mathieu; Gottschalk, Marcelo; Gagnon, Fleur; Van Calsteren, Marie-Rose

2012-01-01

Streptococcus suis type 2 is a major swine pathogen and a zoonotic agent, causing meningitis in both swine and humans. S. suis infects the host through the respiratory route, reaches the bloodstream, and persists until breaching into the central nervous system. The capsular polysaccharide (CPS) of S. suis type 2 is considered a key virulence factor of the bacteria. Though CPS allows S. suis to adhere to the membrane of cells of the immune system, it provides protection against phagocytosis. In fact, nonencapsulated mutants are easily internalized and killed by macrophages and dendritic cells. The objective of this work was to study the molecular mechanisms by which the CPS of S. suis prevents phagocytosis. By using latex beads covalently linked with purified CPS, it was shown that CPS itself was sufficient to inhibit entry of both latex beads and bystander fluorescent beads into macrophages. Upon contact with macrophages, encapsulated S. suis was shown to destabilize lipid microdomains at the cell surface, to block nitric oxide (NO) production during infection, and to prevent lactosylceramide accumulation at the phagocytic cup during infection. In contrast, the nonencapsulated mutant was easily internalized via lipid rafts, in a filipin-sensitive manner, leading to lactosylceramide recruitment and strong NO production. This is the first report to identify a role for CPS in lipid microdomain stability and to recognize an interaction between S. suis and lactosylceramide in phagocytes. PMID:22124659

The relationship between child protection contact and mental health outcomes among Canadian adults with a child abuse history.

PubMed

Afifi, Tracie O; McTavish, Jill; Turner, Sarah; MacMillan, Harriet L; Wathen, C Nadine

2018-05-01

Despite being a primary response to child abuse, it is currently unknown whether contact with child protection services (CPS) does more good than harm. The aim of the current study was to examine whether contact with CPS is associated with improved mental health outcomes among adult respondents who reported experiencing child abuse, after adjusting for sociodemographic factors and abuse severity. The data were drawn from the 2012 Canadian Community Health Survey-Mental Health (CCHS-2012), which used a multistage stratified cluster design (household-level response rate = 79.8%). Included in this study were individuals aged 18 years and older living in the 10 Canadian provinces (N = 23,395). Child abuse included physical abuse, sexual abuse, and exposure to intimate partner violence (IPV). Mental health outcomes included lifetime mental disorders, lifetime and past year suicidal ideation, plans, and attempts, and current psychological well-being and functioning and distress. All models were adjusted for sociodemographic factors and severity of child abuse. For the majority of outcomes, there were no statistically significant differences between adults with a child abuse history who had CPS contact compared to those without CPS contact. However, those with CPS contact were more likely to report lifetime suicide attempts. These findings suggest that CPS contact is not associated with improved mental health outcomes. Implications are discussed. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Comparison of Tension-Band Wiring With the Cable Pin System in Patella Fractures: A Randomized Prospective Study.

PubMed

Tian, Qing-xian; Hai, Yong; Du, Xin-ru; Xu, Zi-yu; Lu, Tie; Shan, Lei; Liu, Yang; Zhou, Jun-lin

2015-12-01

To compare the outcome of tension-band wiring (TBW) with the cable pin system (CPS) for transverse fractures of the patella. Randomized prospective study. Academic Level I trauma center. From February 2008 to December 2011, 73 consecutive patients with transverse fractures of the patella were prospectively enrolled in this study. The patients were randomly divided into 2 groups: one group was treated using the CPS, and the other group was treated using the modified TBW. The clinical outcome assessment included analyses of the radiographic images, the modified Hospital for Special Surgery scoring system, and complications. The follow-up time ranged from 12 to 29 months. All fractures healed, with a union rate of 100%. The fracture healing time was significantly shorter in the CPS group (8.51 ± 2.59 weeks, n = 34) compared with the TBW group (11.79 ± 3.04 weeks, n = 39). Postoperative complications in the CPS and TBW groups were observed in 1 and 9 patients, respectively, a difference that was statistically significant. The mean Hospital for Special Surgery score for the CPS group (90.53 ± 5.19 points) was significantly higher than that for the TBW group (81.36 ± 12.71 points). The CPS is a viable option for transverse fractures of the patella and is associated with a shorter healing time, fewer complications, and better function than TBW. Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Inferring Roles in Defense from Metabolic Allocation of Rice Diterpenoids.

PubMed

Lu, Xuan; Zhang, Juan; Brown, Benjamin; Li, Riqing; Rodríguez-Romero, Julio; Berasategui, Aileen; Liu, Bo; Xu, Meimei; Luo, Dangping; Pan, Zhiqiang; Baerson, Scott; Gershenzon, Jonathan; Li, Zhaohu; Sesma, Ane; Yang, Bing; Peters, Reuben J

2018-04-24

Among their responses to microbial infection, plants deploy an arsenal of natural antibiotic products. These historically have been identified on the basis of their antibiotic activity in vitro, which leaves open the question of their relevance to defense in planta. The vast majority of such natural products from the important crop plant rice (Oryza sativa) are diterpenoids whose biosynthesis proceeds via either ent- or syn- copalyl diphosphate (CPP) intermediates, and which were isolated on the basis of their antibiotic activity against the fungal blast pathogen Magnaporthe oryzae. However, rice plants in which the gene for the syn-CPP synthase Os-CPS4 is knocked-out do not exhibit increased susceptibility to M. oryzae. Here we show that knocking-out or knocking-down Os-CPS4 actually decreases susceptibility to the bacterial leaf blight pathogen Xanthomonas oryzae. By contrast, genetic manipulation of the gene for the ent-CPP synthase Os-CPS2 alters susceptibility to both M. oryzae and X. oryzae. Despite the secretion of diterpenoids dependent on Os-CPS2 or Os-CPS4 from roots, neither knock-out exhibited significant changes in the composition of their rhizosphere bacterial communities. Nevertheless, rice plants allocate substantial metabolic resources towards syn- and ent-CPP derived diterpenoids upon infection/induction. Further investigation revealed that Os-CPS4 plays a role in fungal non-host disease resistance. Thus, examination of metabolic allocation provides important clues into physiological function. © 2018 American Society of Plant Biologists. All rights reserved.

Japan Meteorological Agency/Meteorological Research Institute-Coupled Prediction System version 2 (JMA/MRI-CPS2): atmosphere-land-ocean-sea ice coupled prediction system for operational seasonal forecasting

NASA Astrophysics Data System (ADS)

Takaya, Yuhei; Hirahara, Shoji; Yasuda, Tamaki; Matsueda, Satoko; Toyoda, Takahiro; Fujii, Yosuke; Sugimoto, Hiroyuki; Matsukawa, Chihiro; Ishikawa, Ichiro; Mori, Hirotoshi; Nagasawa, Ryoji; Kubo, Yutaro; Adachi, Noriyuki; Yamanaka, Goro; Kuragano, Tsurane; Shimpo, Akihiko; Maeda, Shuhei; Ose, Tomoaki

2018-02-01

This paper describes the Japan Meteorological Agency/Meteorological Research Institute-Coupled Prediction System version 2 (JMA/MRI-CPS2), which was put into operation in June 2015 for the purpose of performing seasonal predictions. JMA/MRI-CPS2 has various upgrades from its predecessor, JMA/MRI-CPS1, including improved resolution and physics in its atmospheric and oceanic components, introduction of an interactive sea-ice model and realistic initialization of its land component. Verification of extensive re-forecasts covering a 30-year period (1981-2010) demonstrates that JMA/MRI-CPS2 possesses improved seasonal predictive skills for both atmospheric and oceanic interannual variability as well as key coupled variability such as the El Niño-Southern Oscillation (ENSO). For ENSO prediction, the new system better represents the forecast uncertainty and transition/duration of ENSO phases. Our analysis suggests that the enhanced predictive skills are attributable to incremental improvements resulting from all of the changes, as is apparent in the beneficial effects of sea-ice coupling and land initialization on 2-m temperature predictions. JMA/MRI-CPS2 is capable of reasonably representing the seasonal cycle and secular trends of sea ice. The sea-ice coupling remarkably enhances the predictive capability for the Arctic 2-m temperature, indicating the importance of this factor, particularly for seasonal predictions in the Arctic region.

Commentary: taking a deep breath before reflecting on differential response.

PubMed

Merkel-Holguin, Lisa; Bross, Donald C

2015-01-01

Although there are certainly limitations to each and every research and evaluation project in child welfare, as with other fields of study, understanding DR as a CPS reform has been fostered through many thoughtful and rigorous studies that have employed random control trial evaluation designs. For each assumption addressed in this commentary, we have raised a few questions. For all interested in CPS reform, other questions arise because child protection and child welfare professionals are trying to encourage more scientific ways of thinking as a means of engendering improvements: 1. Has the research on DR spotlighted the inadequacy of CPS interventions, either AR or IR? A high percentage of CPS responses are short-term. Is it reasonable to expect significant differences between AR and IR families and improvements in the CPS population, given that families often present with problems characterized as intractable but the intensity of the CPS response, coupled with limited service availability and accessibility, may not be sufficient to meet family needs? 2. Has the DR research, which has mainly focused on AR families, also highlighted the glaring absence of quality research in what is effective in producing positive outcomes for families that receive traditional child abuse and neglect investigations? 3. Does the implementation of DR move the CPS field ahead in terms of making better triage decisions, identifying especially those that require CPS involvement as compared to those who will benefit from but might not absolutely need intervention? Is 'triage' an explicit assumption of the DR innovation? Is it an implicit assumption of DR, however defined? If triage is not part of the research, does the ability of child protection to respond both differentially and also correctly to cases needing most, some, or no attention remain unknown? Until there is a reliable and valid way for determining for which families services are most urgently needed, are many reforms in CPS at risk of not producing the outcomes desired? 4. Are there other unintended consequences of either accepting or rejecting DR that might not have been considered? Our current perspective is to state the obvious and point out that rarely are scientifically or "evidence-based" changes in practice achieved or discredited in a decade or two, much more a scant few years. Breathing deeply from time to time, and even pausing for reflection once in awhile, are useful habits for taking on long-range and difficult human endeavors.

Andrographis paniculata transcriptome provides molecular insights into tissue-specific accumulation of medicinal diterpenes.

PubMed

Garg, Anchal; Agrawal, Lalit; Misra, Rajesh Chandra; Sharma, Shubha; Ghosh, Sumit

2015-09-02

Kalmegh (Andrographis paniculata) has been widely exploited in traditional medicine for the treatment of infectious diseases and health disorders. Ent-labdane-related diterpene (ent-LRD) specialized (i.e., secondary) metabolites of kalmegh such as andrographolide, neoandrographolide and 14-deoxy-11,12-didehydroandrographolide, are known for variety of pharmacological activities. However, due to the lack of genomic and transcriptomic information, underlying molecular basis of ent-LRDs biosynthesis has remained largely unknown. To identify candidate genes of the ent-LRD biosynthetic pathway, we performed comparative transcriptome analysis using leaf and root tissues that differentially accumulate ent-LRDs. De novo assembly of Illumina HiSeq2000 platform-generated paired-end sequencing reads resulted into 69,011 leaf and 64,244 root transcripts which were assembled into a total of 84,628 unique transcripts. Annotation of these transcripts to the Uniprot, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Carbohydrate-Active Enzymes (CAZy) databases identified candidate transcripts of the ent-LRD biosynthetic pathway. These included transcripts that encode enzymes of the plastidial 2C-methyl-D-erythritol-4-phosphate pathway which provides C5 isoprenoid precursors for the ent-LRDs biosynthesis, geranylgeranyl diphosphate synthase, class II diterpene synthase (diTPS), cytochrome P450 monooxygenase and glycosyltransferase. Three class II diTPSs (ApCPS1, ApCPS2 and ApCPS3) that showed distinct tissue-specific expression profiles and are phylogenetically related to the dicotyledon ent-copalyl diphosphate synthases, are identified. ApCPS1, ApCPS2 and ApCPS3 encode for 832-, 817- and 797- amino acids proteins of 55-63 % identity, respectively. Spatio-temporal patterns of transcripts and ent-LRDs accumulation are consistent with the involvement of ApCPS1 in general (i.e., primary) metabolism for the biosynthesis of phytohormone gibberellin, ApCPS2 in leaf specialized ent-LRDs biosynthesis and ApCPS3 in root diterpene biosynthesis. Moreover, simple sequence repeats (SSRs) that might assist in genotyping and developing specific chemotypes were identified in transcripts of the specialized metabolic pathways, including ent-LRDs. Comparative analysis of root and leaf transcriptomes disclosed novel genes of the ent-LRD biosynthetic pathway, including three class II diTPSs that showed discrete spatio-temporal expression patterns; thus, suggesting their participation into distinct diterpene metabolic pathways of kalmegh. Overall, these results will be useful in understanding molecular basis of the medicinal ent-LRDs biosynthesis and developing breeding strategies for improving their yields.

The number of multinucleated trophoblastic giant cells in the basal decidua is decreased in retained placenta.

PubMed

van Beekhuizen, H J; Joosten, I; de Groot, A N J A; Lotgering, F K; van der Laak, J; Bulten, J

2009-09-01

Retained placenta (RP) is a major cause of obstetric haemorrhage. The aim of the study was to obtain a better understanding of the mechanisms that cause some placentas to become retained, while most are not. 23 RPs clinically diagnosed as placenta adhesiva and 10 control placentas (CPs) were examined for differences in trophoblast fusion into multinucleated trophoblastic giant cells (MTGCs), defects in the basal decidua, and decidual attachment of myometrial fibres. The number of MTGCs in the basal decidua was significantly smaller in RPs (0.23 MTGC/standard length) than in CPs (1.11 MTGC/standard length) (p<0.001). Defects in the decidua were observed in 4% of the RPs and in 0% of the CPs. Myometrial fibres were attached to the decidua in 78% of the RPs and in 0% of the CPs (p<0.001). In placenta adhesiva compared with CPs, significantly less MTGCs were present in the basal decidua, the basal decidua was intact, and myometrial fibres were more frequently attached to the basal decidua. It is speculated that these findings may indicate that defective fusion of trophoblastic cells into MTGCs plays a causative role in placenta adhesiva.

The CPS Plasma Award at the Intel Science and Engineering Fair

NASA Astrophysics Data System (ADS)

Berry, Lee

2012-10-01

For the past eight years, the Coalition for Plasma Science (CPS) has presented an award for a plasma project at the Intel International Science and Engineering Fair (ISEF). We reported on the first five years of this award at the 2009 DPP Symposium. Pulsed neutron-producing experiments are a recurring topic, with the efforts now turning to applications. The most recent award at the Pittsburgh ISEF this past May was given for analysis of data from Brookhaven's Relativistic Heavy Ion Collider. The effort had the goal of understanding the fluid properties of the quark-gluon plasma. All of the CPS award-winning projects so far have been based on experiments, with four awards going to women students and four to men. In 2009 we noted that the number and quality of projects was improving. Since then, as we we predicted (hoped for), that trend has continued. The CPS looks forward to continuing its work with students who are excited about the possibilities of plasma. You too can share this excitement by judging at the 2013 fair in Phoenix on May 12-17. Information may be obtained by emailing cps@plasmacoalition.org.

Cortisol production patterns in young children living with birth parents vs children placed in foster care following involvement of Child Protective Services.

PubMed

Bernard, Kristin; Butzin-Dozier, Zachary; Rittenhouse, Joseph; Dozier, Mary

2010-05-01

To examine differences in waking to bedtime cortisol production between children who remained with birth parents vs children placed in foster care following involvement of Child Protective Services (CPS). Between-subject comparison of cortisol patterns among 2 groups of children. Children referred from the child welfare system. Three hundred thirty-nine children aged 2.9 to 31.4 months who were living with birth parents (n = 155) or placed in foster care (n = 184) following CPS involvement as well as 96 unmatched children from low-risk environments. Main Exposures Involvement by CPS and foster care. Main Outcome Measure Salivary cortisol samples obtained at waking and bedtime for children on 2 days. Child Protective Services-involved children who continued to live with birth parents and CPS-involved children placed in foster care differed in cortisol production, with children living with their birth parents showing flatter slopes in waking to bedtime values. Continuing to live with birth parents following involvement of CPS is associated with greater perturbation to the diurnal pattern of cortisol production than living with foster parents. Foster care may have a regulating influence on children's cortisol among children who have experienced maltreatment.

SecureCPS: Defending a nanosatellite cyber-physical system

NASA Astrophysics Data System (ADS)

Forbes, Lance; Vu, Huy; Udrea, Bogdan; Hagar, Hamilton; Koutsoukos, Xenofon D.; Yampolskiy, Mark

2014-06-01

Recent inexpensive nanosatellite designs employ maneuvering thrusters, much as large satellites have done for decades. However, because a maneuvering nanosatellite can threaten HVAs on-­orbit, it must provide a level of security typically reserved for HVAs. Securing nanosatellites with maneuvering capability is challenging due to extreme cost, size, and power constraints. While still in the design process, our low-­cost SecureCPS architecture promises to dramatically improve security, to include preempting unknown binaries and detecting abnormal behavior. SecureCPS also applies to a broad class of cyber-­physical systems (CPS), such as aircraft, cars, and trains. This paper focuses on Embry-­Riddle's ARAPAIMA nanosatellite architecture, where we assume any off-­the-­shelf component could be compromised by a supply chain attack.1 Based on these assumptions, we have used Vanderbilt's Cyber Physical -­ Attack Description Language (CP-­ADL) to represent realistic attacks, analyze how these attacks propagate in the ARAPAIMA architecture, and how to defeat them using the combination of a low-­cost Root of Trust (RoT) Module, Global InfoTek's Advanced Malware Analysis System (GAMAS), and Anomaly Detection by Machine Learning (ADML).2 Our most recent efforts focus on refining and validating the design of SecureCPS.

Potential use of multispectral imaging technology to identify moisture content and water-holding capacity in cooked pork sausages.

PubMed

Ma, Fei; Zhang, Bin; Wang, Wu; Li, Peijun; Niu, Xiangli; Chen, Conggui; Zheng, Lei

2018-03-01

The traditional detection methods for moisture content (MC) and water-holding capacity (WHC) in cooked pork sausages (CPS) are destructive, time consuming, require skilled personnel and are not suitable for online industry applications. The goal of this work was to explore the potential of multispectral imaging (MSI) in combination with multivariate analysis for the identification of MC and WHC in CPS. Spectra and textures of 156 CPS treated by six salt concentrations (0-2.5%) were analyzed using different calibration models to find the most optimal results of predicting MC and WHC in CPS. By using the fused data of spectra and textures, partial least squares regression models performed well for determining the MC and WHC, with a correlation coefficient (r) of 0.949 and 0.832, respectively. Additionally, their spatial distribution in CPS could be visualized via applying prediction equations to transfer each pixel in the image. Results of satisfactory detection and visualization of the MC and WHC showed that MSI has the potential to serve as a rapid and non-destructive method for use in sausage industry. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Corn peptides protect against thioacetamide-induced hepatic fibrosis in rats.

PubMed

Lv, Jie; Nie, Zhi-Kui; Zhang, Jiu-Liang; Liu, Feng-Yan; Wang, Zhen-Zhen; Ma, Zhi-Li; He, Hui

2013-10-01

Certain bioactive peptides are reported to be able to alleviate hepatic fibrosis. Our previous work has confirmed the hepatoprotective effect of corn peptides (CPs) that are prepared from a high protein by-product, corn gluten meal, on acute liver injury in an animal model. However, the antifibrotic activity of CPs remained to be elucidated. In this study, the hepatoprotective effect of CPs on thioacetamide (TAA)-induced liver fibrosis was tested. Results showed that CPs (100 mg/kg body weight) significantly decreased the levels of alanine transaminase/aspartate transaminase, laminin, type IV collagen, and type III collagen in serum and increased the serum albumin levels and total antioxidant capacity. Additionally, with CP treatment (100 mg/kg body weight), a significant decrease was observed in the levels of malondialdehyde, nitric oxide, hydroxyproline, transforming growth factor β1, and lactate dehydrogenase activity as well as the liver index, while the activity of superoxidedismutase was significantly increased in livers. The histological and morphological analysis showed that the hepatocyte structure in CP-treated rats was superior to that of TAA-injured rats, and inflammation and fibrosis were also ameliorated. Therefore, CPs can be used as an option for prevention and adjuvant therapy of liver fibrosis.

Automated Derivation of Complex System Constraints from User Requirements

NASA Technical Reports Server (NTRS)

Foshee, Mark; Murey, Kim; Marsh, Angela

2010-01-01

The Payload Operations Integration Center (POIC) located at the Marshall Space Flight Center has the responsibility of integrating US payload science requirements for the International Space Station (ISS). All payload operations must request ISS system resources so that the resource usage will be included in the ISS on-board execution timelines. The scheduling of resources and building of the timeline is performed using the Consolidated Planning System (CPS). The ISS resources are quite complex due to the large number of components that must be accounted for. The planners at the POIC simplify the process for Payload Developers (PD) by providing the PDs with a application that has the basic functionality PDs need as well as list of simplified resources in the User Requirements Collection (URC) application. The planners maintained a mapping of the URC resources to the CPS resources. The process of manually converting PD's science requirements from a simplified representation to a more complex CPS representation is a time-consuming and tedious process. The goal is to provide a software solution to allow the planners to build a mapping of the complex CPS constraints to the basic URC constraints and automatically convert the PD's requirements into systems requirements during export to CPS.

Prenatal whole exome sequencing: the views of clinicians, scientists, genetic counsellors and patient representatives.

PubMed

Quinlan-Jones, Elizabeth; Kilby, Mark D; Greenfield, Sheila; Parker, Michael; McMullan, Dominic; Hurles, Matthew E; Hillman, Sarah C

2016-10-01

Focus groups were conducted with individuals involved in prenatal diagnosis to determine their opinions relating to whole exome sequencing in fetuses with structural anomalies. Five representatives of patient groups/charities (PRGs) and eight clinical professionals (CPs) participated. Three focus groups occurred (the two groups separately and then combined). Framework analysis was performed to elicit themes. A thematic coding frame was identified based on emerging themes. Seven main themes (consent, analysis, interpretation/reinterpretation of results, prenatal issues, uncertainty, incidental findings and information access) with subthemes emerged. The main themes were raised by both groups, apart from 'analysis', which was raised by CPs only. Some subthemes were raised by PRGs and CPs (with different perspectives). Others were raised either by PRGs or CPs, showing differences in patient/clinician agendas. Prenatal consent for whole exome sequencing is not a 'perfect' process, but consent takers should be fully educated regarding the test. PRGs highlighted issues involving access to results, feeling that women want to know all information. PRGs also felt that patients want reinterpretation of results over time, whilst CPs felt that interpretation should be performed at the point of testing only. © 2016 John Wiley & Sons, Ltd. © 2016 John Wiley & Sons, Ltd.

The effect of material hardship on child protective service involvement.

PubMed

Yang, Mi-Youn

2015-03-01

This study employs four waves of survey data on 1,135 families from the Illinois Families Study, a longitudinal panel study of Temporary Assistance for Needy Families in Illinois. This study explores the following issues within this low-income population: (1) whether material hardships are associated with child protective services (CPS) investigations, (2) whether the effect of material hardship on CPS differs by the type of child maltreatment investigated, and (3) whether psychological distress mediates the association between material hardship and CPS involvement. Results from pooled and fixed effects logistic regressions suggest that caregivers who experience material hardship are more likely to become involved in CPS. In general, investigated neglect reports are responsive to particular types of hardship such as housing and food, while investigated physical abuse reports are responsive to levels of hardship regardless of specific types. The association between material hardship and CPS involvement is not fully explained by depressive symptoms or parenting stress. The study results suggest that in order to prevent child maltreatment, it may be necessary to address a family's unmet material needs through economic support interventions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Chemical tagging of chlorinated phenols for their facile detection and analysis by NMR spectroscopy

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

Valdez, Carlos A.; Leif, Roald N.

2015-03-22

A derivatization method that employs diethyl (bromodifluoromethyl) phosphonate (DBDFP) to efficiently tag the endocrine disruptor pentachlorophenol (PCP) and other chlorinated phenols (CPs) along with their reliable detection and analysis by NMR is presented. The method accomplishes the efficient alkylation of the hydroxyl group in CPs with the difluoromethyl (CF 2H) moiety in extremely rapid fashion (5 min), at room temperature and in an environmentally benign manner. The approach proved successful in difluoromethylating a panel of 18 chlorinated phenols, yielding derivatives that displayed unique 1H, 19F NMR spectra allowing for the clear discrimination between isomerically related CPs. Due to its biphasicmore » nature, the derivatization can be applied to both aqueous and organic mixtures where the analysis of CPs is required. Furthermore, the methodology demonstrates that PCP along with other CPs can be selectively derivatized in the presence of other various aliphatic alcohols, underscoring the superiority of the approach over other general derivatization methods that indiscriminately modify all analytes in a given sample. The present work demonstrates the first application of NMR on the qualitative analysis of these highly toxic and environmentally persistent species.« less

Citrus psorosis virus RNA 1 is of negative polarity and potentially encodes in its complementary strand a 24K protein of unknown function and 280K putative RNA dependent RNA polymerase.

PubMed

Naum-Onganía, Gabriela; Gago-Zachert, Selma; Peña, Eduardo; Grau, Oscar; Garcia, Maria Laura

2003-10-01

Citrus psorosis virus (CPsV), the type member of genus Ophiovirus, has three genomic RNAs. Complete sequencing of CPsV RNA 1 revealed a size of 8184 nucleotides and Northern blot hybridization with chain specific probes showed that its non-coding strand is preferentially encapsidated. The complementary strand of RNA 1 contains two open reading frames (ORFs) separated by a 109-nt intergenic region, one located near the 5'-end potentially encoding a 24K protein of unknown function, and another of 280K containing the core polymerase motifs characteristic of viral RNA-dependent RNA polymerases (RdRp). Comparison of the core RdRp motifs of negative-stranded RNA viruses, supports grouping CPsV, Ranunculus white mottle virus (RWMV) and Mirafiori lettuce virus (MiLV) within the same genus (Ophiovirus), constituting a monophyletic group separated from all other negative-stranded RNA viruses. Furthermore, RNAs 1 of MiLV, CPsV and RWMV are similar in size and those of MiLV and CPsV also in genomic organization and sequence.

Screening by coral green fluorescent protein (GFP)-like chromoproteins supports a role in photoprotection of zooxanthellae

NASA Astrophysics Data System (ADS)

Smith, E. G.; D'Angelo, C.; Salih, A.; Wiedenmann, J.

2013-06-01

Green fluorescent protein (GFP)-like pigments are responsible for the vivid colouration of many reef-building corals and have been proposed to act as photoprotectants. Their role remains controversial because the functional mechanism has not been elucidated. We provide direct evidence to support a photoprotective role of the non-fluorescent chromoproteins (CPs) that form a biochemically and photophysically distinct group of GFP-like proteins. Based on observations of Acropora nobilis from the Great Barrier Reef, we explored the photoprotective role of CPs by analysing five coral species under controlled conditions. In vitro and in hospite analyses of chlorophyll excitation demonstrate that screening by CPs leads to a reduction in chlorophyll excitation corresponding to the spectral properties of the specific CPs present in the coral tissues. Between 562 and 586 nm, the CPs maximal absorption range, there was an up to 50 % reduction of chlorophyll excitation. The screening was consistent for established and regenerating tissue and amongst symbiont clades A, C and D. Moreover, among two differently pigmented morphs of Acropora valida grown under identical light conditions and hosting subclade type C3 symbionts, high CP expression correlated with reduced photodamage under acute light stress.

Cyber Physical System Modelling of Distribution Power Systems for Dynamic Demand Response

NASA Astrophysics Data System (ADS)

Chu, Xiaodong; Zhang, Rongxiang; Tang, Maosen; Huang, Haoyi; Zhang, Lei

2018-01-01

Dynamic demand response (DDR) is a package of control methods to enhance power system security. A CPS modelling and simulation platform for DDR in distribution power systems is presented in this paper. CPS modelling requirements of distribution power systems are analyzed. A coupled CPS modelling platform is built for assessing DDR in the distribution power system, which combines seamlessly modelling tools of physical power networks and cyber communication networks. Simulations results of IEEE 13-node test system demonstrate the effectiveness of the modelling and simulation platform.

Fine Particulate Matter and Total Mortality in Cancer Prevention Study Cohort Reanalysis.

PubMed

Enstrom, James E

2017-01-01

In 1997 the US Environmental Protection Agency (EPA) established the National Ambient Air Quality Standard (NAAQS) for fine particulate matter (PM 2.5 ), largely because of its positive relationship to total mortality in the 1982 American Cancer Society Cancer Prevention Study (CPS II) cohort. Subsequently, EPA has used this relationship as the primary justification for many costly regulations, most recently the Clean Power Plan. An independent analysis of the CPS II data was conducted in order to test the validity of this relationship. The original CPS II questionnaire data, including 1982 to 1988 mortality follow-up, were analyzed using Cox proportional hazards regression. Results were obtained for 292 277 participants in 85 counties with 1979-1983 EPA Inhalable Particulate Network PM 2.5 measurements, as well as for 212 370 participants in the 50 counties used in the original 1995 analysis. The 1982 to 1988 relative risk (RR) of death from all causes and 95% confidence interval adjusted for age, sex, race, education, and smoking status was 1.023 (0.997-1.049) for a 10 µg/m 3 increase in PM 2.5 in 85 counties and 1.025 (0.990-1.061) in the 50 original counties. The fully adjusted RR was null in the western and eastern portions of the United States, including in areas with somewhat higher PM 2.5 levels, particularly 5 Ohio Valley states and California. No significant relationship between PM 2.5 and total mortality in the CPS II cohort was found when the best available PM 2.5 data were used. The original 1995 analysis found a positive relationship by selective use of CPS II and PM 2.5 data. This independent analysis of underlying data raises serious doubts about the CPS II epidemiologic evidence supporting the PM 2.5 NAAQS. These findings provide strong justification for further independent analysis of the CPS II data.

Fine Particulate Matter and Total Mortality in Cancer Prevention Study Cohort Reanalysis

PubMed Central

2017-01-01

Background: In 1997 the US Environmental Protection Agency (EPA) established the National Ambient Air Quality Standard (NAAQS) for fine particulate matter (PM2.5), largely because of its positive relationship to total mortality in the 1982 American Cancer Society Cancer Prevention Study (CPS II) cohort. Subsequently, EPA has used this relationship as the primary justification for many costly regulations, most recently the Clean Power Plan. An independent analysis of the CPS II data was conducted in order to test the validity of this relationship. Methods: The original CPS II questionnaire data, including 1982 to 1988 mortality follow-up, were analyzed using Cox proportional hazards regression. Results were obtained for 292 277 participants in 85 counties with 1979-1983 EPA Inhalable Particulate Network PM2.5 measurements, as well as for 212 370 participants in the 50 counties used in the original 1995 analysis. Results: The 1982 to 1988 relative risk (RR) of death from all causes and 95% confidence interval adjusted for age, sex, race, education, and smoking status was 1.023 (0.997-1.049) for a 10 µg/m3 increase in PM2.5 in 85 counties and 1.025 (0.990-1.061) in the 50 original counties. The fully adjusted RR was null in the western and eastern portions of the United States, including in areas with somewhat higher PM2.5 levels, particularly 5 Ohio Valley states and California. Conclusion: No significant relationship between PM2.5 and total mortality in the CPS II cohort was found when the best available PM2.5 data were used. The original 1995 analysis found a positive relationship by selective use of CPS II and PM2.5 data. This independent analysis of underlying data raises serious doubts about the CPS II epidemiologic evidence supporting the PM2.5 NAAQS. These findings provide strong justification for further independent analysis of the CPS II data. PMID:28473741

The Study of Carbamoyl Phosphate Synthetase 1 Deficiency Sheds Light on the Mechanism for Switching On/Off the Urea Cycle.

PubMed

Díez-Fernández, Carmen; Gallego, José; Häberle, Johannes; Cervera, Javier; Rubio, Vicente

2015-05-20

Carbamoyl phosphate synthetase 1 (CPS1) deficiency (CPS1D) is an inborn error of the urea cycle having autosomal (2q34) recessive inheritance that can cause hyperammonemia and neonatal death or mental retardation. We analyzed the effects on CPS1 activity, kinetic parameters and enzyme stability of missense mutations reported in patients with CPS1 deficiency that map in the 20-kDa C-terminal domain of the enzyme. This domain turns on or off the enzyme depending on whether the essential allosteric activator of CPS1, N-acetyl-L-glutamate (NAG), is bound or is not bound to it. To carry out the present studies, we exploited a novel system that allows the expression in vitro and the purification of human CPS1, thus permitting site-directed mutagenesis. These studies have clarified disease causation by individual mutations, identifying functionally important residues, and revealing that a number of mutations decrease the affinity of the enzyme for NAG. Patients with NAG affinity-decreasing mutations might benefit from NAG site saturation therapy with N-carbamyl-L-glutamate (a registered drug, the analog of NAG). Our results, together with additional present and prior site-directed mutagenesis data for other residues mapping in this domain, suggest an NAG-triggered conformational change in the β4-α4 loop of the C-terminal domain of this enzyme. This change might be an early event in the NAG activation process. Molecular dynamics simulations that were restrained according to the observed effects of the mutations are consistent with this hypothesis, providing further backing for this structurally plausible signaling mechanism by which NAG could trigger urea cycle activation via CPS1. Copyright © 2015 Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and Genetics Society of China. Published by Elsevier Ltd. All rights reserved.

Occurrences, sources and risk assessment of short- and medium-chain chlorinated paraffins in sediments from the middle reaches of the Yellow River, China.

PubMed

Qiao, Lin; Xia, Dan; Gao, Lirong; Huang, Huiting; Zheng, Minghui

2016-12-01

Chlorinated paraffins (CPs), one class of hydrophobic and toxic compounds, are easily adsorbed into sediments and then pose potential risks to the ecosystem and human health. However, few researches on short- and medium-chain CPs (SCCPs and MCCPs) in sediments have been performed. In order to comprehensively investigate the spatial distributions, sources, and ecological risks of CPs, sediments collected from the middle reaches of the Yellow River were analyzed by two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC × GC-TOFMS). The concentrations of SCCPs and MCCPs ranged from 11.6 to 9.76 × 10 3  ng/g dry weight (dw) and from 8.33 to 168 ng/g dw, respectively. No significant correlation was found between total organic carbon (TOC) and CP concentrations (P > 0.05). The spatial distributions showed that contamination levels of CPs were relevant to human activities. In addition, two types of sediment samples were classified by hierarchical cluster analysis (HCA) and results indicated the predominant congener groups were C 10 Cl 6-7 for SCCPs and C 14 Cl 7-8 for MCCPs. Principal component analysis (PCA) revealed that SCCPs and MCCPs in the sediments may have different sources, and SCCPs are likely to come from the production and use of CP-42 and CP-52. Moreover, complex environmental processes, including long-range transportation via the atmosphere and/or river, deposition and degradation of CPs, resulted in increased abundances of short chain and low chlorinated congeners in sediment samples compared with commercial mixtures, and different homolog patterns among samples. The significant negative correlation between SCCP concentrations and MCCP/SCCP ratios could be related to long-range transport of CPs. A preliminary risk assessment indicated that CPs at current levels posed no significant ecological risk. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genome-wide annotation of cuticular proteins in the oriental fruit fly (Bactrocera dorsalis), changes during pupariation and expression analysis of CPAP3 protein genes in response to environmental stresses.

PubMed

Chen, Er-Hu; Hou, Qiu-Li; Dou, Wei; Wei, Dan-Dan; Yue, Yong; Yang, Rui-Lin; Yang, Pei-Jin; Yu, Shuai-Feng; De Schutter, Kristof; Smagghe, Guy; Wang, Jin-Jun

2018-06-01

Cuticular proteins (CPs) are essential components of the insect cuticle as they create a structural and protective shield and may have a role in insect development. In this paper, we studied the CPs in the oriental fruit fly (Bactrocera dorsalis), one of the most economically important pests in the Tephritidae family around the world. The availability of a complete genome sequence (NCBI Assembly: ASM78921v2) allowed the identification of 164 CP genes in B. dorsalis. Comparative analysis of the CPs in B. dorsalis with those in the model insect Drosophila melanogaster and the closely related Ceratitis capitata, and CPs from mosquitoes, Lepidoptera, Hymenoptera and Coleoptera identified Diptera-specific genes and cuticle development patterns. Analysis of their evolutionary relationship revealed that some CP families had evolved according to the phylogeny of the different insect species, while others shared a closer relationship based on domain architecture. Subsequently, transcriptome analysis showed that while most of the CPs (60-100% of the family members) are expressed in the epidermis, some were also present in internal organs such as the fat body and the reproductive organs. Furthermore, the study of the expression profiles throughout development revealed a profound change in the expression of CPs during the formation of the puparium (pupariation). Further analysis of the expression profiles of the CPAP3 genes under various environmental stresses revealed them to be involved in the response to pesticides and arid and extreme temperatures conditions. In conclusion, the data provide a particular overview of CPs and their evolutionary and transcriptional dynamics, and in turn they lay a molecular foundation to explore their roles in the unique developmental process of insect metamorphosis and stress responses. Copyright © 2018 Elsevier Ltd. All rights reserved.

Removal of 10-nm contaminant particles from Si wafers using CO2 bullet particles.

PubMed

Kim, Inho; Hwang, Kwangseok; Lee, Jinwon

2012-04-11

Removal of nanometer-sized contaminant particles (CPs) from substrates is essential in successful fabrication of nanoscale devices. The particle beam technique that uses nanometer-sized bullet particles (BPs) moving at supersonic velocity was improved by operating it at room temperature to achieve higher velocity and size uniformity of BPs and was successfully used to remove CPs as small as 10 nm. CO2 BPs were generated by gas-phase nucleation and growth in a supersonic nozzle; appropriate size and velocity of the BPs were obtained by optimizing the nozzle contours and CO2/He mixture fraction. Cleaning efficiency greater than 95% was attained. BP velocity was the most important parameter affecting removal of CPs in the 10-nm size range. Compared to cryogenic Ar or N2 particles, CO2 BPs were more uniform in size and had higher velocity and, therefore, cleaned CPs more effectively.

Mitochondrial endonuclease G mediates breakdown of paternal mitochondria upon fertilization.

PubMed

Zhou, Qinghua; Li, Haimin; Li, Hanzeng; Nakagawa, Akihisa; Lin, Jason L J; Lee, Eui-Seung; Harry, Brian L; Skeen-Gaar, Riley Robert; Suehiro, Yuji; William, Donna; Mitani, Shohei; Yuan, Hanna S; Kang, Byung-Ho; Xue, Ding

2016-07-22

Mitochondria are inherited maternally in most animals, but the mechanisms of selective paternal mitochondrial elimination (PME) are unknown. While examining fertilization in Caenorhabditis elegans, we observed that paternal mitochondria rapidly lose their inner membrane integrity. CPS-6, a mitochondrial endonuclease G, serves as a paternal mitochondrial factor that is critical for PME. We found that CPS-6 relocates from the intermembrane space of paternal mitochondria to the matrix after fertilization to degrade mitochondrial DNA. It acts with maternal autophagy and proteasome machineries to promote PME. Loss of cps-6 delays breakdown of mitochondrial inner membranes, autophagosome enclosure of paternal mitochondria, and PME. Delayed removal of paternal mitochondria causes increased embryonic lethality, demonstrating that PME is important for normal animal development. Thus, CPS-6 functions as a paternal mitochondrial degradation factor during animal development. Copyright © 2016, American Association for the Advancement of Science.

Chronic periodontitis can affect the levels of potential oral cancer salivary mRNA biomarkers.

PubMed

Cheng, Y-S L; Jordan, L; Chen, H-S; Kang, D; Oxford, L; Plemons, J; Parks, H; Rees, T

2017-06-01

More than 100 salivary constituents have been found to show levels significantly different in patients with oral squamous cell carcinoma (OSCC) from those found in healthy controls, and therefore have been suggested to be potential salivary biomarkers for OSCC detection. However, many of these potential OSCC salivary biomarkers are also involved in chronic inflammation, and whether the levels of these biomarkers could be affected by the presence of chronic periodontitis was not known. The objective of this pilot study was therefore to measure the levels of seven previously reported potential OSCC salivary mRNA biomarkers in patients with chronic periodontitis and compare them to levels found in patients with OSCC and healthy controls. The seven salivary mRNAs were interleukin (IL)-8, IL-1β, dual specificity phosphatase 1, H3 histone family 3A, ornithine decarboxylase antizyme 1, S100 calcium-binding protein P (S100P) and spermidine/spermine N1-acetyltransferase 1. Unstimulated whole saliva samples were collected from a total of 105 human subjects from the following four study groups: OSCC; CPNS (chronic periodontitis, moderate to severe degree, non-smokers); CPS (chronic periodontitis, moderate to severe degree, smokers); and healthy controls. Levels of each mRNA in patient groups (OSCC or chronic periodontitis) relative to the healthy controls were determined by a pre-amplification reverse transcription-quantitative polymerase chain reaction approach with nested gene-specific primers. Results were recorded and analyzed by the Bio-Rad CFX96 Real-Time System. Mean fold changes between each pair of patient vs. control groups were analyzed by the Mann-Whitney U-test with Bonferroni corrections. Only S100P showed significantly higher levels in patients with OSCC compared to both patients with CPNS (p = 0.003) and CPS (p = 0.007). The difference in S100P levels between patients with OSCC and healthy controls was also marginally significant (p = 0.009). There was no significant difference in the levels of salivary IL-8, IL-1β and dual specificity phosphatase 1 mRNAs between patients with OSCC and patients with CPNS (p = 0.510, 0.058 and 0.078, respectively); no significant difference in levels of salivary ornithine decarboxylase antizyme 1 and spermine N1-acetyltransferase mRNAs between patients with OSCC and patients with CPS (p = 0.318 and 0.764, respectively); and no significant difference in levels of the H3 histone family 3A mRNA between patients with OSCC and either CPS (p = 0.449) or healthy controls (p = 0.107). Salivary S100P mRNA could be a reliable biomarker for OSCC detection, regardless of the presence of chronic periodontitis. The presence of chronic periodontitis could significantly affect the levels of the other six mRNAs, and negatively influence reliability for using them as biomarkers for oral cancer detection. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The effect of parental intellectual disability status on child protection service worker decision making.

PubMed

Proctor, S N; Azar, S T

2013-12-01

There is evidence to suggest that parents with an intellectual disability (ID) constitute a higher proportion of child-protective services (CPS) cases than would be expected based on the prevalence of ID in the general population. Researchers have suggested that the stereotypic assumptions and expectations that CPS workers have about parents with an ID might influence decisions and responses made to such parents. This study examined whether parental ID (having an ID vs. not) had an effect on CPS workers' emotional reactions, attributions and decisions about risk to the child, whether to remove the child and workers' general willingness to help the parent. Two hundred and twelve CPS workers read vignettes describing parents who were labelled as either having or not having an ID. Workers responded to the vignettes by making ratings of their emotional reactions, attributions and decisions regarding risk, removal and helping. CPS workers made significantly higher ratings of pity, willingness to help and risk for parents with an ID than for parents without an ID. Lower ratings of anger and disgust were found for parents with an ID than for parents without an ID. Parents' intellectual status did not have a direct effect on workers' attributions or removal decisions. The results show evidence for the influence of stereotypes regarding parental ID due to its differential effect on CPS workers' emotional reactions and decisions about child risk and their willingness to help. © 2012 The Authors. Journal of Intellectual Disability Research © 2012 John Wiley & Sons Ltd, MENCAP & IASSID.

Recent developments in capabilities for analysing chlorinated paraffins in environmental matrices: A review.

PubMed

van Mourik, Louise M; Leonards, Pim E G; Gaus, Caroline; de Boer, Jacob

2015-10-01

Concerns about the high production volumes, persistency, bioaccumulation potential and toxicity of chlorinated paraffin (CP) mixtures, especially short-chain CPs (SCCPs), are rising. However, information on their levels and fate in the environment is still insufficient, impeding international classifications and regulations. This knowledge gap is mainly due to the difficulties that arise with CP analysis, in particular the chromatographic separation within CPs and between CPs and other compounds. No fully validated routine analytical method is available yet and only semi-quantitative analysis is possible, although the number of studies reporting new and improved methods have rapidly increased since 2010. Better cleanup procedures that remove interfering compounds, and new instrumental techniques, which distinguish between medium-chain CPs (MCCPs) and SCCPs, have been developed. While gas chromatography coupled to an electron capture negative ionisation mass spectrometry (GC/ECNI-MS) remains the most commonly applied technique, novel and promising use of high resolution time of flight MS (TOF-MS) has also been reported. We expect that recent developments in high resolution TOF-MS and Orbitrap technologies will further improve the detection of CPs, including long-chain CPs (LCCPs), and the group separation and quantification of CP homologues. Also, new CP quantification methods have emerged, including the use of mathematical algorithms, multiple linear regression and principal component analysis. These quantification advancements are also reflected in considerably improved interlaboratory agreements since 2010. Analysis of lower chlorinated paraffins (

The effect of care pathways for hip fractures: a systematic review.

PubMed

Leigheb, Fabrizio; Vanhaecht, Kris; Sermeus, Walter; Lodewijckx, Cathy; Deneckere, Svin; Boonen, Steven; Boto, Paulo Alexandre Faria; Mendes, Rita Veloso; Panella, Massimiliano

2012-07-01

We performed a systematic review for primary studies on care pathways (CPs) for hip fracture (HF). The online databases MEDLINE-PubMed, Ovid-EMBASE, CINAHL-EBSCO host, and The Cochrane Library (Cochrane Central Register of Clinical Trials, Health Technology Assessment Database, NHS Economic Evaluation Database) were searched. Two researchers reviewed the literature independently. Primary studies that met predefined inclusion criteria were assessed for their methodological quality. A total of 15 publications were included: 15 primary studies corresponding with 12 main investigations. Primary studies were evaluated for clinical outcomes, process outcomes, and economic outcomes. The studies assessed a wide range of outcome measures. While a number of divergent clinical outcomes were reported, most studies showed positive results of process management and health-services utilization. In terms of mortality, the results provided evidence for a positive impact of CPs on in-hospital mortality. Most studies also showed a significantly reduced risk of complications, including medical complications, wound infections, and pressure sores. Moreover, time-span process measures showed that an improvement in the organization of care was achieved through the use of CPs. Conflicting results were observed with regard to functional recovery and mobility between patients treated with CPs compared to usual care. Although our review suggests that CPs can have positive effects in patients with HF, the available evidence is insufficient for formal recommendations. There is a need for more research on CPs with selected process and outcome indicators, for in-hospital and postdischarge management of HF, with an emphasis on well-designed randomized trials.

Chronic postnatal stress induces voluntary alcohol intake and modifies glutamate transporters in adolescent rats.

PubMed

Odeon, María Mercedes; Andreu, Marcela; Yamauchi, Laura; Grosman, Mauricio; Acosta, Gabriela Beatriz

2015-01-01

Postnatal stress alters stress responses for life, with serious consequences on the central nervous system (CNS), involving glutamatergic neurotransmission and development of voluntary alcohol intake. Several drugs of abuse, including alcohol and cocaine, alter glutamate transport (GluT). Here, we evaluated effects of chronic postnatal stress (CPS) on alcohol intake and brain glutamate uptake and transporters in male adolescent Wistar rats. For CPS from postnatal day (PD) 7, pups were separated from their mothers and exposed to cold stress (4 °C) for 1 h daily for 20 days; controls remained with their mothers. Then they were exposed to either voluntary ethanol (6%) or dextrose (1%) intake for 7 days (5-7 rats per group), then killed. CPS: (1) increased voluntary ethanol intake, (2) did not affect body weight gain or produce signs of toxicity with alcohol exposure, (3) increased glutamate uptake by hippocampal synaptosomes in vitro and (4) reduced protein levels (Western measurements) in hippocampus and frontal cortex of glial glutamate transporter-1 (GLT-1) and excitatory amino-acid transporter-3 (EAAT-3) but increased glutamate aspartate transporter (GLAST) levels. We propose that CPS-induced decrements in GLT-1 and EAAT-3 expression levels are opposed by activation of a compensatory mechanism to prevent excitotoxicity. A greater role for GLAST in total glutamate uptake to prevent enlarged extracellular glutamate levels is inferred. Although CPS strongly increased intake of ethanol, this had little impact on effects of CPS on brain glutamate uptake or transporters. However, the impact of early life adverse events on glutamatergic neurotransmission may underlie increased alcohol consumption in adulthood.

The infundibulo-tuberal syndrome caused by craniopharyngiomas: clinicopathological evidence from an historical French cohort (1705-1973).

PubMed

Castro-Dufourny, Inés; Carrasco, Rodrigo; Prieto, Ruth; Barrios, Laura; Pascual, José M

2015-10-01

Infundibulo-tuberal syndrome groups endocrine, metabolic and behavioral disturbances caused by lesions involving the upper neurohypophysis (median eminence) and adjacent basal hypothalamus (tuber cinereum). It was originally described by Henri Claude and Jean Lhermitte in 1917, in a patient with a craniopharyngioma. This study investigates the clinical, pathological and surgical evidence verifying the infundibulo-tuberal syndrome caused by craniopharyngiomas (CPs). A systematic retrospective review of craniopharyngiomas reported in French literature between 1705 and 1973 was conducted. A total of 128 well described reports providing a comprehensive clinical and pathological description of the tumors were selected. This series represents the historical French cohort of CPs reported in the pre-CT/MRI era. Three major syndromes caused by CPs were categorized: pituitary syndrome (35%), infundibulo-tuberal syndrome (52%) and hypothalamic syndrome (49%). CP topography was significantly related to the type of syndrome described (p < 0.001). Infundibulo-tuberal syndrome occurred in CPs which replaced or invaded the third ventricle floor. In contrast, the majority of sellar/suprasellar CPs growing below the third ventricle showed a pituitary syndrome (82%). Cases with hypothalamic syndrome were characterized by anatomical integrity of the pituitary gland and stalk (p = 0.033) and occurred predominantly in adults older than 41 years old (p < 0.005). Among infundibulo-tuberal symptoms, abnormal somnolence was not related with the presence of hydrocephalus. All squamous-papillary CPs presented psychiatric disturbances (p < 0.001). This historical CP cohort evidences a clinical-topographical correlation between the patient's type of syndrome and the anatomical structures involved by the tumor along the hypophysial-hypothalamic axis.

Predictors of inadequate prenatal care in methamphetamine-using mothers in New Zealand and the United States.

PubMed

Wu, Min; Lagasse, Linda L; Wouldes, Trecia A; Arria, Amelia M; Wilcox, Tara; Derauf, Chris; Newman, Elana; Shah, Rizwan; Smith, Lynne M; Neal, Charles R; Huestis, Marilyn A; Dellagrotta, Sheri; Lester, Barry M

2013-04-01

This study compared patterns of prenatal care among mothers who used methamphetamine (MA) during pregnancy and non-using mothers in the US and New Zealand (NZ), and evaluated associations among maternal drug use, child protective services (CPS) referral, and inadequate prenatal care in both countries. The sample consisted of 182 mothers in the MA-Exposed and 196 in the Comparison groups in the US, and 107 mothers in the MA-Exposed and 112 in the Comparison groups in NZ. Positive toxicology results and/or maternal report of MA use during pregnancy were used to identify MA use. Information about sociodemographics, prenatal care and prenatal substance use was collected by maternal interview. MA-use during pregnancy is associated with lower socioeconomic status, single marital status, and CPS referral in both NZ and the US. Compared to their non-using counterparts, MA-using mothers in the US had significantly higher rates of inadequate prenatal care. No association was found between inadequate care and MA-use in NZ. In the US, inadequate prenatal care was associated with CPS referral, but not in NZ. Referral to CPS for drug use only composed 40 % of all referrals in the US, but only 15 % of referrals in NZ. In our study population, prenatal MA-use and CPS referral eclipse maternal sociodemographics in explanatory power for inadequate prenatal care. The predominant effect of CPS referral in the US is especially interesting, and should encourage further research on whether the US policy of mandatory reporting discourages drug-using mothers from seeking antenatal care.

75 FR 17928 - Nisso America, Inc.; Filing of Food Additive Petition

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-08

... dietary supplements. FOR FURTHER INFORMATION CONTACT: Laura Dye, Center for Food Safety and Applied... from 145 cPs to 10 cPs and to permit its use as a binder in dietary supplements. The agency has...

Customer premises services market demand assessment 1980 - 2000: Volume 2

NASA Technical Reports Server (NTRS)

Gamble, R. B.; Saporta, L.; Heidenrich, G. A.

1983-01-01

Potential customer premises service (CPS), telecommunication services, potential CPS user classes, a primary research survey, comparative economics, market demand forcasts, distance distribution of traffic, segmentation of market demand, and a nationwide traffic distribution model are discussed.

Comparison of Capsular Genes of Streptococcus pneumoniae Serotype 6A, 6B, 6C, and 6D Isolates▿

PubMed Central

Song, Jae-Hoon; Baek, Jin Yang; Ko, Kwan Soo

2011-01-01

Recently, Streptococcus pneumoniae serotypes 6C and 6D have been identified. It is thought that they emerged by the replacement of wciNβ in the capsular loci of serotypes 6A and 6B, respectively. However, their evolution has not been unveiled yet. To investigate the evolution of four serotypes of S. pneumoniae serogroup 6, four genes of the capsular polysaccharide synthesis (cps) locus, wchA, wciN, wciO, and wciP, of isolates of S. pneumoniae serotypes 6A, 6B, 6C, and 6D were sequenced. Multilocus sequence typing (MLST) was performed to investigate their genetic backgrounds. The wchA gene of serotype 6C and 6D isolates was distinct from that of serotype 6A and 6B isolates, which may suggest cotransfer of wchA with wciNβ. Otherwise, serotypes 6C and 6D displayed different genetic backgrounds from serotypes 6A and 6B, which was suggested by MLST analysis. In addition, serotype 6C isolates showed distinct wciP polymorphisms from other serotypes, which also indicated that serotype 6C had not recently originated from serotype 6A. Although serotype 6D shared the same amino acid polymorphisms of wciO with serotype 6B, wciP of serotype 6D differed from that of serotype 6B. The data indicate the implausibility of the scenario of a recent emergence of the cps locus of serotype 6D by genetic recombination between serotypes 6B and 6C. In addition, five serotype 6A and 6B isolates (6X group) displayed cps loci distinct from those of other isolates. The cps locus homogeneity and similar sequence types in MLST analysis suggest that most of the 6X group of isolates originated from the same ancestor and that the entire cps locus might have recently been transferred from an unknown origin. Serotype 6B isolates showed two or more cps locus subtypes, indicating a recombination-mediated mosaic structure of the cps locus of serotype 6B. The collective data favor the emergence of cps loci of serotypes 6A, 6B, 6C, and 6D by complicated recombination. PMID:21411593

In Situ X-ray Absorption Spectroscopy Studies of Discharge Reactions in a Thick Cathode of a Lithium Sulfur Battery

DOE PAGES

Wujcik, Kevin H.; Wang, Dunyang Rita; Pascal, Tod A.; ...

2016-12-01

Lithium sulfur (Li-S) batteries are well known for their high theoretical specific capacities, but are plagued with scientific obstacles that make practical implementation of the technology impossible. The success of Li-S batteries will likely necessitate the use of thick sulfur cathodes that enable high specific energy densities. However, little is known about the fundamental reaction mechanisms and chemical processes that take place in thick cathodes, as most research has focused on studying thinner cathodes that enable high performance. In this study, in situ X-ray absorption spectroscopy at the sulfur K-edge is used to examine the back of a 115 μmmore » thick Li-S cathode during discharge. Our results show that in such systems, where electrochemical reactions between sulfur and lithium are likely to proceed preferentially toward the front of the cathode, lithium polysulfide dianions formed in this region diffuse to the back of the cathode during discharge. We show that high conversion of elemental sulfur is achieved by chemical reactions between elemental sulfur and polysulfide dianions of intermediate chain length (Li 2S x, 4 ≤ x ≤ 6). Our work suggests that controlling the formation and diffusion of intermediate chain length polysulfide dianions is crucial for insuring full utilization of thick sulfur cathodes.« less

A Fluorinated Ether Electrolyte Enabled High Performance Prelithiated Graphite/Sulfur Batteries

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

Chen, Shuru; Yu, Zhaoxin; Gordin, Mikhail L.

Lithium/sulfur (Li/S) batteries have attracted great attention as a promising energy storage technology, but so far their practical applications are greatly hindered by issues of polysulfide shuttling and unstable lithium/electrolyte interface. To address these issues, a feasible strategy is to construct a rechargeable prelithiated graphite/sulfur batteries. In this study, a fluorinated ether of bis(2,2,2-trifluoroethyl) ether (BTFE) was reported to blend with 1,3-dioxolane (DOL) for making a multifunctional electrolyte of 1.0 M LiTFSI DOL/BTFE (1:1, v/v) to enable high performance prelithiated graphite/S batteries. First, the electrolyte significantly reduces polysulfide solubility to suppress the deleterious polysulfide shuttling and thus improves capacity retentionmore » of sulfur cathodes. Second, thanks to the low viscosity and good wettability, the fluorinated electrolyte dramatically enhances the reaction kinetics and sulfur utilization of high-areal-loading sulfur cathodes. More importantly, this electrolyte forms a stable solid-electrolyte interphase (SEI) layer on graphite surface and thus enables remarkable cyclability of graphite anodes. Lastly, by coupling prelithiated graphite anodes with sulfur cathodes with high areal capacity of ~3 mAh cm -2, we demonstrate prelithiated graphite/sulfur batteries that show high sulfur-specific capacity of ~1000 mAh g -1 and an excellent capacity retention of >65% after 450 cycles at C/10.« less

Hydrogen sulfide and its roles in Saccharomyces cerevisiae in a winemaking context.

PubMed

Huang, Chien-Wei; Walker, Michelle E; Fedrizzi, Bruno; Gardner, Richard C; Jiranek, Vladimir

2017-09-01

The rotten-egg odour of hydrogen sulfide (H2S) produced by the yeast Saccharomyces cerevisiae has attracted considerable research interest due to its huge impact on the sensory quality of fermented foods and beverages. To date, the yeast genetic mechanisms of H2S liberation during wine fermentation are well understood and yeast strains producing low levels of H2S have been developed. Studies have also revealed that H2S is not just a by-product in the biosynthesis of the sulfur-containing amino acids, but indeed a vital molecule involved in detoxification, population signalling and extending cellular life span. Moreover, polysulfides have recently emerged as key players in signalling and the sensory quality of wine because their degradation leads to the release of H2S. This review will focus on the recent findings on the production of H2S and polysulfides in S. cerevisiae and summarise their potential roles in yeast survival and winemaking. Recent advances in techniques for the detection of H2S and polysulfides offer an exciting opportunity to uncover the novel genes and pathways involved in their formation from different sulfur sources. This knowledge will not only provide further insights into yeast sulfur metabolism, but could potentially improve the sensory quality of wine. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A Fluorinated Ether Electrolyte Enabled High Performance Prelithiated Graphite/Sulfur Batteries

DOE PAGES

Chen, Shuru; Yu, Zhaoxin; Gordin, Mikhail L.; ...

2017-02-03

Lithium/sulfur (Li/S) batteries have attracted great attention as a promising energy storage technology, but so far their practical applications are greatly hindered by issues of polysulfide shuttling and unstable lithium/electrolyte interface. To address these issues, a feasible strategy is to construct a rechargeable prelithiated graphite/sulfur batteries. In this study, a fluorinated ether of bis(2,2,2-trifluoroethyl) ether (BTFE) was reported to blend with 1,3-dioxolane (DOL) for making a multifunctional electrolyte of 1.0 M LiTFSI DOL/BTFE (1:1, v/v) to enable high performance prelithiated graphite/S batteries. First, the electrolyte significantly reduces polysulfide solubility to suppress the deleterious polysulfide shuttling and thus improves capacity retentionmore » of sulfur cathodes. Second, thanks to the low viscosity and good wettability, the fluorinated electrolyte dramatically enhances the reaction kinetics and sulfur utilization of high-areal-loading sulfur cathodes. More importantly, this electrolyte forms a stable solid-electrolyte interphase (SEI) layer on graphite surface and thus enables remarkable cyclability of graphite anodes. Lastly, by coupling prelithiated graphite anodes with sulfur cathodes with high areal capacity of ~3 mAh cm -2, we demonstrate prelithiated graphite/sulfur batteries that show high sulfur-specific capacity of ~1000 mAh g -1 and an excellent capacity retention of >65% after 450 cycles at C/10.« less

Enhanced performance of lithium-sulfur batteries with an ultrathin and lightweight MoS2/carbon nanotube interlayer

NASA Astrophysics Data System (ADS)

Yan, Lingjia; Luo, Nannan; Kong, Weibang; Luo, Shu; Wu, Hengcai; Jiang, Kaili; Li, Qunqing; Fan, Shoushan; Duan, Wenhui; Wang, Jiaping

2018-06-01

Ultrathin and lightweight MoS2/carbon nanotube (CNT) interlayers are developed to effectively trap polysulfides in high-performance lithium-sulfur (Li-S) batteries. The MoS2/CNT interlayer is constructed by loading MoS2 nanosheets onto a cross-stacked CNT film. The CNT film with excellent conductivity and superior mechanical properties provides the Li-S batteries with a uniform conductive network, a supporting skeleton for the MoS2 nanosheets, as well as a physical barrier for the polysulfides. Moreover, chemical interactions and bonding between the MoS2 nanosheets and the polysulfides are evident. The electrode with the MoS2/CNT interlayer delivers an attractive specific capacity of 784 mA h g-1 at a high capacity rate of 10 C. In addition, the electrode demonstrates a high initial capacity of 1237 mA h g-1 and a capacity fade as low as -0.061% per cycle over 500 charge/discharge cycles at 0.2 C. The problem of self-discharge can also be suppressed with the introduction of the MoS2/CNT interlayer. The simple fabrication procedure, which is suitable for commercialization, and the outstanding electrochemical performance of the cells with the MoS2/CNT interlayer demonstrate a great potential for the development of high-performance Li-S batteries.

In Situ Chemical Imaging of Solid-Electrolyte Interphase Layer Evolution in Li–S Batteries

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

Nandasiri, Manjula I.; Camacho-Forero, Luis E.; Schwarz, Ashleigh M.

Parasitic reactions of electrolyte and polysulfide with the Li-anode in lithium sulfur (Li-S) batteries lead to the formation of solid-electrolyte interphase (SEI) layers, which are the major reason behind severe capacity fading in these systems. Despite numerous studies, the evolution mechanism of the SEI layer and specific roles of polysulfides and other electrolyte components are still unclear. Here, we report an in-situ X-ray photoelectron spectroscopy (XPS) and chemical imaging analysis combined with ab initio molecular dynamics (AIMD) computational modeling to gain fundamental understanding regarding the evolution of SEI layers on Li-anodes within Li-S batteries. A multi-modal approach involving AIMD modelingmore » and in-situ XPS characterization uniquely reveals the chemical identity and distribution of active participants in parasitic reactions as well as the SEI layer evolution mechanism. The SEI layer evolution has three major stages: the formation of a primary composite mixture phase involving stable lithium compounds (Li 2S, LiF, Li 2O etc); and formation of a secondary matrix type phase due to cross interaction between reaction products and electrolyte components, which is followed by a highly dynamic mono-anionic polysulfide (i.e. LiS 5) fouling process. In conclusion, these new molecular-level insights into the SEI layer evolution on Li- anodes are crucial for delineating effective strategies for the development of Li–S batteries.« less

In Situ Chemical Imaging of Solid-Electrolyte Interphase Layer Evolution in Li–S Batteries

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

Nandasiri, Manjula I.; Camacho-Forero, Luis E.; Schwarz, Ashleigh M.

Parasitic reactions of electrolyte and polysulfide with the Li-anode in lithium sulfur (Li-S) batteries lead to the for-mation of solid electrolyte interphase (SEI) layers, which are the major reason behind severe capacity fading in these systems. Despite numerous studies, the evolution mechanism of the SEI layer and specific roles of polysulfides and oth-er electrolyte components are still unclear. We report an in-situ X-ray photoelectron spectroscopy (XPS) and chemical imaging analysis combined with ab initio molecular dynamics (AIMD) computational modeling to gain fundamental understanding regarding the evolution of SEI layers on Li-anodes within Li-S batteries. A multi-modal approach in-volving AIMD modelingmore » and in-situ XPS characterization uniquely reveals the chemical identity and distribution of active participants in parasitic reactions as well as the SEI layer evolution mechanism. The SEI layer evolution has three major stages: the formation of a primary composite mixture phase involving stable lithium compounds (Li2S, LiF, Li2O etc); and formation of a secondary matrix type phase due to cross interaction between reaction products and elec-trolyte components, which is followed by a highly dynamic mono-anionic polysulfide (i.e. LiS5) fouling process. These new molecular-level insights into the SEI layer evolution on Li- anodes are crucial for delineating effective strategies for the development of Li–S batteries.« less

Cathode composites for Li-S batteries via the use of oxygenated porous architectures.

PubMed

Demir-Cakan, Rezan; Morcrette, Mathieu; Nouar, Farid; Davoisne, Carine; Devic, Thomas; Gonbeau, Danielle; Dominko, Robert; Serre, Christian; Férey, Gérard; Tarascon, Jean-Marie

2011-10-12

Li-S rechargeable batteries are attractive for electric transportation because of their low cost, environmentally friendliness, and superior energy density. However, the Li-S system has yet to conquer the marketplace, owing to its drawbacks, namely, soluble polysulfide formation. To tackle this issue, we present here a strategy based on the use of a mesoporous chromium trimesate metal-organic framework (MOF) named MIL-100(Cr) as host material for sulfur impregnation. Electrodes containing sulfur impregnated within the pores of the MOF were found to show a marked increase in the capacity retention of Li-S cathodes. Complementary transmission electron microscopy and X-ray photoelectron spectroscopy measurements demonstrated the reversible capture and release of the polysulfides by the pores of MOF during cycling and evidenced a weak binding between the polysulphides and the oxygenated framework. Such an approach was generalized to other mesoporous oxide structures, such as mesoporous silica, for instance SBA-15, having the same positive effect as the MOF on the capacity retention of Li-S cells. Besides pore sizes, the surface activity of the mesoporous additives, as observed for the MOF, appears to also have a pronounced effect on enhancing the cycle performance. Increased knowledge about the interface between polysulfide species and oxide surfaces could lead to novel approaches in the design and fabrication of long cycle life S electrodes.

In Situ Chemical Imaging of Solid-Electrolyte Interphase Layer Evolution in Li–S Batteries

DOE PAGES

Nandasiri, Manjula I.; Camacho-Forero, Luis E.; Schwarz, Ashleigh M.; ...

2017-05-03

Parasitic reactions of electrolyte and polysulfide with the Li-anode in lithium sulfur (Li-S) batteries lead to the formation of solid-electrolyte interphase (SEI) layers, which are the major reason behind severe capacity fading in these systems. Despite numerous studies, the evolution mechanism of the SEI layer and specific roles of polysulfides and other electrolyte components are still unclear. Here, we report an in-situ X-ray photoelectron spectroscopy (XPS) and chemical imaging analysis combined with ab initio molecular dynamics (AIMD) computational modeling to gain fundamental understanding regarding the evolution of SEI layers on Li-anodes within Li-S batteries. A multi-modal approach involving AIMD modelingmore » and in-situ XPS characterization uniquely reveals the chemical identity and distribution of active participants in parasitic reactions as well as the SEI layer evolution mechanism. The SEI layer evolution has three major stages: the formation of a primary composite mixture phase involving stable lithium compounds (Li 2S, LiF, Li 2O etc); and formation of a secondary matrix type phase due to cross interaction between reaction products and electrolyte components, which is followed by a highly dynamic mono-anionic polysulfide (i.e. LiS 5) fouling process. In conclusion, these new molecular-level insights into the SEI layer evolution on Li- anodes are crucial for delineating effective strategies for the development of Li–S batteries.« less

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

NONE

This report documents the objectives and the conceptual and methodological approach used in the development of the Coal Production Submodule (CPS). It provides a description of the CPS for model analysts and the public. The Coal Market Module provides annual forecasts of prices, production, and consumption of coal.

Compositions for directed alignment of conjugated polymers

DOEpatents

Kim, Jinsang; Kim, Bong-Gi; Jeong, Eun Jeong

2016-04-19

Conjugated polymers (CPs) achieve directed alignment along an applied flow field and a dichroic ratio of as high as 16.67 in emission from well-aligned thin films and fully realized anisotropic optoelectronic properties of CPs in field-effect transistor (FET).

Biochemical Characterization of CPS-1, a Subclass B3 Metallo-β-Lactamase from a Chryseobacterium piscium Soil Isolate.

PubMed

Gudeta, Dereje Dadi; Pollini, Simona; Docquier, Jean-Denis; Bortolaia, Valeria; Rossolini, Gian Maria; Guardabassi, Luca

2015-12-14

CPS-1 is a subclass B3 metallo-β-lactamase from a Chryseobacterium piscium isolate collected from soil, showing 68% amino acid identity to the GOB-1 enzyme. CPS-1 was overproduced in Escherichia coli Rosetta (DE3), purified by chromatography, and biochemically characterized. This enzyme exhibits a broad-spectrum substrate profile, including penicillins, cephalosporins, and carbapenems, which overall resembles those of L1, GOB-1, and acquired subclass B3 enzymes AIM-1 and SMB-1. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

[Congenital portosystemic shunts: experience of the western region of France over 5 years].

PubMed

Hubert, G; Giniès, J-L; Dabadie, A; Tourtelier, Y; Willot, S; Pariente, D; Lefrançois, T; Caldari, D

2014-11-01

Congenital portosystemic shunts (CPS) are rare vascular malformations that lead to liver metabolic modifications. The aim of this study was to describe the management and outcome of CPS in children who were followed in the western region of France and to compare our experience to a literature review. This retrospective study reports nine children with CPS who were followed in the western region of France between 2008 and 2013. Among these nine children, six were detected by prenatal ultrasonography, one had cholestatic jaundice during the postoperative period, one had cholestatic jaundice during the first days of life, and one had dyspnea and fatigue. Two children had liver tumors. The CPS was intrahepatic for four children and extrahepatic for two children. Three others had a patent ductus venosus. Among the intrahepatic shunts that were discovered before the age of 2 years, three closed spontaneously. The five other shunts were closed surgically or by interventional radiology techniques, after angiography for four children. After closure of eight shunts, the outcome was favorable for six children. Two children presented complications after surgery: portal hypertension and portal thrombus. When CPS is suspected, the diagnosis should be confirmed and complications should be investigated. Shunt closure restores portal flow and prevents complications. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Radiation induced in-situ cationic polymerization of polystyrene organogel for selective absorption of cholorophenols from petrochemical wastewater.

PubMed

Ghobashy, Mohamed M; Younis, Sherif A; Elhady, Mohamed A; Serp, Philippe

2018-03-15

A new in-situ cationic polymerization was performed to synthesize a cross-linked (91%) polystyrene (PS) organogel through tetrachloroethylene radiolysis assisted by 60 Co gamma rays. Hoernschemeyer diagram and swelling capacity test show a better selectivity of PS organogel to chlorinated molecules compared to ester, hydrocarbons and alcohols organic molecules by 80-184 folds. Response surface modeling (RSM) of CPs (2,4,6-trichlorophenol) sorption from artificial wastewater confirm superiority of PS organogel to absorb 1746 μmol CPs/g (∼345 mg CPs/g) at broad pH (4-10) and temperature (25-45 °C). Based on ANOVA statistic, simulated CPs absorption model onto PS organogel was successfully developed, with accuracy of prediction of R 2 ≈ R Adj 2 of 0.991-0.995 and lower coefficient of variation of 2.73% with F model of 611.4 at p < .0001. Particularly, the usage of PS organogel for petroleum wastewater reclamation exhibited higher absorption affinities for all the organic contaminants especially for CPs (>99%) by non-covalent and/or dispersive interaction mechanisms with a well-term reusability and good stability up to 5 cycles. Copyright © 2018 Elsevier Ltd. All rights reserved.

Knowledge, attitudes and awareness regarding fertility preservation among oncologists and clinical practitioners in Lebanon.

PubMed

Ghazeeri, Ghina; Zebian, Dina; Nassar, Anwar H; Harajly, Sally; Abdallah, Alain; Hakimian, Stephanie; Skaiff, Bassem; Abbas, Hussein A; Awwad, Johnny

2016-06-01

Fertility preservation (FP) aims to help individuals overcome the infertility associated with cancer treatments such as chemotherapy and radiation. The objective of this study was to assess the awareness, attitudes and knowledge of oncologists' and clinical practitioners' (CPs) about fertility preservation and its options in Lebanon. This was a cross-sectional study with surveys carried out between March 2012 and February 2013 on CPs at the American University of Beirut Medical Centre and Saint Jude's Children Cancer Centre as well as all registered oncologists in Lebanon. Ninety percent of CPs (n = 88) and 94% of oncologists (n = 53) agreed that fertility preservation should be discussed with patient before their cancer treatment. Our data showed a gender bias in relation to patients being informed of their FP options, as well as conflicting knowledge of FP options available in Lebanon among oncologists. The CPs were more likely to have accurate knowledge of FP options and treatment than oncologists. A proactive approach is required to: (1) increase the awareness and knowledge of FP; (2) improve attitudes towards FP; and (3) encourage its communication between CPs, oncologists and patients in Lebanon. Increased education programs, awareness campaigns and development of dedicated FP centres are needed.

Use of Powder PEG-3350 as a Sole Bowel Preparation: Clinical Case Series of 245 Patients.

PubMed

Arora, Manish; Okolo, Patrick I

2008-07-01

To assess the efficacy of low-volume powder polyethylene glycol (PEG)-3350 as a sole bowel preparation for colonoscopy. This case series examined 245 consecutive patients (a mixture of inpatients and outpatients undergoing screening colonoscopy) at a hospital endoscopy center over a 2-year period. The patients received powder PEG-3350 in the amount of 204 g dissolved in 32 oz of water and taken in 3 divided doses 1 hour apart with 8 oz of water in between each dose. Colon preparation scores (CPS) were used to assess the quality of colon cleansing. The results obtained from the 245 patients were collated and compared to those of patients receiving sodium phosphate, the historical control. The mean CPS was calculated to be 3.43, with a standard deviation of 1.12. Of the 245 patients, 92 were scored with a grade of 4, and 5 patients had incomplete colonoscopies secondary to failure of bowel preparation (CPS=0). Among the remaining patients, 22 and 26 were graded as poor (CPS=1) or fair (CPS=2) bowel preparations, respectively. The low-volume powder PEG-3350 formula used in our case series showed effective colon cleansing and may be considered for use as a sole bowel preparation.