High throughput screening: an in silico solubility parameter approach for lipids and solvents in SLN preparations.

PubMed

Shah, Malay; Agrawal, Yadvendra

2013-01-01

The present paper describes an in silico solubility behavior of drug and lipids, an essential screening study in preparation of solid lipid nanoparticles (SLN). Ciprofloxacin HCl was selected as a model drug along with 11 lipids and 5 organic solvents. In silico miscibility study of drug/lipid/solvent was performed using Hansen solubility parameter approach calculated by group contribution method of Van Krevelen and Hoftyzer. Predicted solubility was validated by determining solubility of lipids in various solvent at different temperature range, while miscibility of drug in lipids was determined by apparent solubility study and partition experiment. The presence of oxygen and OH functionality increases the polarity and hydrogen bonding possibilities of the compound which has reflected the highest solubility parameter values for Geleol and Capmul MCM C8. Ethyl acetate, Geleol and Capmul MCM C8 was identified as suitable organic solvent, solid lipid and liquid lipid respectively based on a solubility parameter approach which was in agreement with the result of an apparent solubility study and partition coefficient. These works demonstrate the validity of solubility parameter approach and provide a feasible predictor to the rational selection of excipients in designing SLN formulation.

Compatibility Assessment of Fuel System Thermoplastics with Bio-Blendstock Fuel Candidates Using Hansen Solubility Analysis

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

Kass, Michael D.; West, Brian H.

The compatibility of key fuel system infrastructure plastics with 39 bio-blendstock fuel candidates was examined using Hansen solubility analysis. Fuel types included multiple alcohols, esters, ethers, ketones, alkenes and one alkane. These compounds were evaluated as neat molecules and as blends with the gasoline surrogate, dodecane, and a mix of dodecane and 10% ethanol (E10D). The plastics included polyphenylene sulfide (PPS), polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyoxymethylene (POM), polybutylene terephthalate (PBT), polypropylene (PP), high density polyethylene (HDPE), along with several nylon grades. These materials have been rigorously studied with other fuel types, and their volume change resultsmore » were found to correspond well with their predicted solubility levels.The compatibility was assessed using Hansen solubility parameters and in many instances peak solubility occurred for blends rather than the neat fuel components. The results showed that good compatibilities can be expected for PPS, PVDF, PET, nylons, acetal, PEI, PVC, HDPE and PBT. PTFE showed potential incompatibilities at low blend concentrations, especially when E10D was used as the base fuel blend. Although, the nylons show good overall compatibility, the results do indicate that mid-range and high alcohol contents may not be suitable for Nylon 6 and Nylon 11 in applications requiring low volume swell. Poor potential compatibility was limited to two plastic types; PETG exposed to mid and high blend levels of the ethers and PP exposed to sabinene and the aromatics. In general, the data showed good compatibility for the majority of the candidate fuels and plastics.« less

Compatibility Assessment of Fuel System Thermoplastics with Bio-Blendstock Fuel Candidates Using Hansen Solubility Analysis

DOE PAGES

Kass, Michael D.; West, Brian H.

2018-01-03

The compatibility of key fuel system infrastructure plastics with 39 bio-blendstock fuel candidates was examined using Hansen solubility analysis. Fuel types included multiple alcohols, esters, ethers, ketones, alkenes and one alkane. These compounds were evaluated as neat molecules and as blends with the gasoline surrogate, dodecane, and a mix of dodecane and 10% ethanol (E10D). The plastics included polyphenylene sulfide (PPS), polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), polyoxymethylene (POM), polybutylene terephthalate (PBT), polypropylene (PP), high density polyethylene (HDPE), along with several nylon grades. These materials have been rigorously studied with other fuel types, and their volume change resultsmore » were found to correspond well with their predicted solubility levels.The compatibility was assessed using Hansen solubility parameters and in many instances peak solubility occurred for blends rather than the neat fuel components. The results showed that good compatibilities can be expected for PPS, PVDF, PET, nylons, acetal, PEI, PVC, HDPE and PBT. PTFE showed potential incompatibilities at low blend concentrations, especially when E10D was used as the base fuel blend. Although, the nylons show good overall compatibility, the results do indicate that mid-range and high alcohol contents may not be suitable for Nylon 6 and Nylon 11 in applications requiring low volume swell. Poor potential compatibility was limited to two plastic types; PETG exposed to mid and high blend levels of the ethers and PP exposed to sabinene and the aromatics. In general, the data showed good compatibility for the majority of the candidate fuels and plastics.« less

Influence of matching solubility parameter of polymer matrix and CNT on electrical conductivity of CNT/rubber composite

PubMed Central

Ata, Seisuke; Mizuno, Takaaki; Nishizawa, Ayumi; Subramaniam, Chandramouli; Futaba, Don N.; Hata, Kenji

2014-01-01

We report a general approach to fabricate elastomeric composites possessing high electrical conductivity for applications ranging from wireless charging interfaces to stretchable electronics. By using arbitrary nine kinds of rubbers as matrices, we experimentally demonstrate that the matching the solubility parameter of CNTs and the rubber matrix is important to achieve higher electrical conductivity in CNT/rubber composite, resulting in continuous conductive pathways leading to electrical conductivities as high as 15 S/cm with 10 vol% CNT in fluorinated rubber. Further, using thermodynamic considerations, we demonstrate an approach to mix CNTs to arbitrary rubber matrices regardless of solubility parameter of matrices by adding small amounts of fluorinated rubber as a polymeric-compatibilizer of CNTs. We thereby achieved electrical conductivities ranging from 1.2 to 13.8 S/cm (10 vol% CNTs) using nine varieties of rubber matrices differing in chemical structures and physical properties. Finally, we investigated the components of solubility parameter of CNT by using Hansen solubility parameters, these findings may useful for controlling solubility parameter of CNTs. PMID:25434701

Solubility studies of inorganic-organic hybrid nanoparticle photoresists with different surface functional groups

NASA Astrophysics Data System (ADS)

Li, Li; Chakrabarty, Souvik; Jiang, Jing; Zhang, Ben; Ober, Christopher; Giannelis, Emmanuel P.

2016-01-01

The solubility behavior of Hf and Zr based hybrid nanoparticles with different surface ligands in different concentrations of photoacid generator as potential EUV photoresists was investigated in detail. The nanoparticles regardless of core or ligand chemistry have a hydrodynamic diameter of 2-3 nm and a very narrow size distribution in organic solvents. The Hansen solubility parameters for nanoparticles functionalized with IBA and 2MBA have the highest contribution from the dispersion interaction than those with tDMA and MAA, which show more polar character. The nanoparticles functionalized with unsaturated surface ligands showed more apparent solubility changes after exposure to DUV than those with saturated ones. The solubility differences after exposure are more pronounced for films containing a higher amount of photoacid generator. The work reported here provides material selection criteria and processing strategies for the design of high performance EUV photoresists.The solubility behavior of Hf and Zr based hybrid nanoparticles with different surface ligands in different concentrations of photoacid generator as potential EUV photoresists was investigated in detail. The nanoparticles regardless of core or ligand chemistry have a hydrodynamic diameter of 2-3 nm and a very narrow size distribution in organic solvents. The Hansen solubility parameters for nanoparticles functionalized with IBA and 2MBA have the highest contribution from the dispersion interaction than those with tDMA and MAA, which show more polar character. The nanoparticles functionalized with unsaturated surface ligands showed more apparent solubility changes after exposure to DUV than those with saturated ones. The solubility differences after exposure are more pronounced for films containing a higher amount of photoacid generator. The work reported here provides material selection criteria and processing strategies for the design of high performance EUV photoresists. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr07334k

Mixed Gas Hydrogen Sulfide Permeability and Separation Using Supported Polyphosphazene Membranes

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

Frederick F. Stewart; Christopher J. Orme

Three phosphazene polymers were characterized for permeability using a suite of pure gases, including H2S where high permeabilities were measured with respect to the other gases in the study. Furthermore, mixed gas selectivities were determined and compared to the ideal gas selectivities for the H2S/CH4, CO2/CH4, and Ar/CH4 gas pairs. The three phosphazenes represent a set of membrane materials differing by their polarities. Description of the polarity of each was performed using Hansen solubility parameters derived from group contributions for each chemical structure. A good correlation was observed between the polar Hansen parameter (äp) and the gas permeabilities of bothmore » CO2 and H2S. Furthermore, permeant gas critical temperatures were also found to correlate with permeability suggesting a solubility driven transport process. A comparison of the mixed gas permeabilities with the corresponding pure gas data revealed good agreement in the data, although the presence of more condensable gases hinders non-polar gas transport resulting in higher separation factors.« less

Hansen Solubility Parameters for Octahedral Oligomeric Silsesquioxanes

DTIC Science & Technology

2012-08-28

Chujo, Y. Synthesis of organic-inorganic polymer hybrids from poly(vinyl chloride ) and polyhedral oligomeric silsesquioxane via CH/pi interaction...referred to as octa(phenethyl), POSS and either polystyrene22 or polyvinyl chloride .23 However, in many cases, the reported solubility of POSS...Acetonitrile 1.82 Fail E- 1.85 Fail E- 2.40 Fail E- Acetone 0.33 Pass E+ 0.58 Pass E+ 1.27 Pass U+ Allyl Chloride 1.64 Fail E- 1.83 Fail E- 1.42 Fail E

Use of Hansen Solubility Parameters in Fuel Treatment Processes

DTIC Science & Technology

2014-03-17

Clearance # Considerations for Rocket Fuel Objective: Utilize liquid/liquid extraction process to improve performance, increase availability, and...1/4)(H1 - H0)2 - (D2 – D0)2 - (1/4) (P2 - P0)2 - (1/4)(H2 - H0)2 ] + RT ln (V1/ V2 ) K = C0,2 / CO,1 Partition coefficient RT ln K = V0( D1...02 – D2-02 ) + RT ln (V1/ V2 ) Di-0 is the distance in “solubility parameter space” between liquid i and impurity 0. For reference, phase 1 = fuel

Comparison of the cohesion-adhesion balance approach to colloidal probe atomic force microscopy and the measurement of Hansen partial solubility parameters by inverse gas chromatography for the prediction of dry powder inhalation performance.

PubMed

Jones, Matthew D; Buckton, Graham

2016-07-25

The abilities of the cohesive-adhesive balance approach to atomic force microscopy (AFM) and the measurement of Hansen partial solubility parameters by inverse gas chromatography (IGC) to predict the performance of carrier-based dry powder inhaler (DPI) formulations were compared. Five model drugs (beclometasone dipropionate, budesonide, salbutamol sulphate, terbutaline sulphate and triamcinolone acetonide) and three model carriers (erythritol, α-lactose monohydrate and d-mannitol) were chosen, giving fifteen drug-carrier combinations. Comparison of the AFM and IGC interparticulate adhesion data suggested that they did not produce equivalent results. Comparison of the AFM data with the in vitro fine particle delivery of appropriate DPI formulations normalised to account for particle size differences revealed a previously observed pattern for the AFM measurements, with a slightly cohesive AFM CAB ratio being associated with the highest fine particle fraction. However, no consistent relationship between formulation performance and the IGC data was observed. The results as a whole highlight the complexity of the many interacting variables that can affect the behaviour of DPIs and suggest that the prediction of their performance from a single measurement is unlikely to be successful in every case. Copyright © 2016 Elsevier B.V. All rights reserved.

Characterization of 2-(2-Methoxyethoxy)ethanol Substituted Phosphazene Polymers Using Pervaporation, Solubility Parameters and Sorption Studies

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

Orme, Christopher Joseph; Klaehn, John Ray; Harrup, Mason Kurt

Two linear phosphazene polymers were synthesized with differing amounts of hydrophilic 2-(2-methoxyethoxy)ethanol (MEE) and hydrophobic 4-methoxyphenol (MEOP) substituted on the backbone. These high polymers were cast into membranes and their permeability to water, methanol, ethanol, and 2-propanol was evaluated as a function of temperature. An additional polymer with a low content of MEE was studied for water permeation and was characterized by trace flux. At higher levels of MEE on the backbone, fluxes of all solvents increased. Solubility also was found to increase with increasing MEE content for all solvents except water. Unexpectedly, water was found to be less solublemore » in the higher MEE polymer, although higher membrane fluxes were observed. Diffusion coefficients showed the following trend: methanol 2-propanol > ethanol water. Finally, the affinity of solvents and polymers was discussed in terms of Hansen solubility parameters.« less

The influence of guaifenesin and ketoprofen on the properties of hot-melt extruded polyethylene oxide films.

PubMed

Crowley, Michael M; Fredersdorf, Anke; Schroeder, Britta; Kucera, Shawn; Prodduturi, Suneela; Repka, Michael A; McGinity, James W

2004-08-01

Films containing polyethylene oxide (PEO) and a model drug, either guaifenesin (GFN) or ketoprofen (KTP), were prepared by hot-melt extrusion. The thermal properties of the hot-melt extruded films were investigated using differential scanning calorimetry (DSC). Scanning electron microscopy (SEM) was used to examine the surface morphology of the films, and wide angle X-ray diffraction (XRD) was used to investigate the crystalline properties of the polymer, drugs and physical mixtures as well as the solid state structure of the films. The stability of the polymer was studied using gel permeation chromatography. The mechanical properties, including percent elongation and tensile strength of the films, were determined on an Instron according to American Society for Testing Materials (ASTM) procedures. The Hansen solubility parameter was calculated using the Hoftyzer or van Krevelen method to estimate the likelihood of drug--polymer miscibility. Both GFN and KTP were stable during the extrusion process. Melting points corresponding to the crystalline drugs were not observed in the films. Crystallization of GFN on the surface of the film was observed at all concentrations studied, however KTP crystallization did not occur until reaching the 15% level. Guaifenesin and ketoprofen were found to decrease drive load, increase PEO stability and plasticize the polymer during extrusion. The Hansen solubility parameters predicted miscibility between PEO and KTP and poor miscibility between PEO and GFN. The predictions of the solubility parameters were in agreement with the XRD and SEM results. The percent elongation decreased with increasing GFN concentrations and significantly increased with increasing levels of KTP. Both GFN and KTP decreased the tensile strength of the extruded film.

Evaluation of reversed-phase nano liquid chromatography conditions by using reversed-phase thin layer chromatography based on Hansen solubility parameters for the analysis of amphiphilic glycosylsphingolipid transformations.

PubMed

Kanie, Yoshimi; Taniuchi, Mizuki; Kanie, Osamu

2018-01-26

Pulse chase analysis is often used in investigating dynamics of cellular substances. Fluorescently labeled lactosyl sphingosine molecule is useful in chasing its transformation, however the analysis of such metabolites in attomole level is of extreme difficult due to the presence of large amount of endogenous amphiphilic molecules such as glycosphingolipids, sphingomyerin, and glycerophospholipids. Nano LC suites for analyzing the attomole scale metabolites, therefore removal of endogenous substances prior to nano LC and finding appropriate nano LC conditions are necessary. Thus, we focused on the solubility of fluorescent BODIPY-labeled lactosylsphingosine (Lac-Sph-BODIPY) to identify suitable solvents to remove endogenous compounds. In this study, we evaluated solvents by using C18 thin layer chromatography (RP TLC). The mobility (R f ) of Lac-Sph-BODIPY against several solvent mixtures on RP TLC were plotted against polarity and hydrogen bonding capability followed by Hansen solubility parameters (HSPs). The optimum solvent mixture with R f  = 0.3 ± 0.1 was chosen for elimination of endogenous phospholipids on a ZrO 2 -SiO 2 cartridge column and subsequent separation by nano LC. Efficient removal of endogenous phospholipids was demonstrated, and good resolution in nano LC analysis of Lac-Sph-BODIPY extracted from Chinese hamster ovary (CHO)-K1 cells was achieved. It was also shown that the amount of exogenously added compound was important in the investigation of metabolites using cultured cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Production of cocrystals in an excipient matrix by spray drying.

PubMed

Walsh, David; Serrano, Dolores R; Worku, Zelalem Ayenew; Norris, Brid A; Healy, Anne Marie

2018-01-30

Spray drying is a well-established scale-up technique for the production of cocrystals. However, to the best of our knowledge, the effect of introducing a third component into the feed solution during the spray drying process has never been investigated. Cocrystal formation in the presence of a third component by a one-step spray drying process has the potential to reduce the number of unit operations which are required to produce a final pharmaceutical product (e.g. by eliminating blending with excipient). Sulfadimidine (SDM), a poorly water soluble active pharmaceutical ingredient (API), and 4-aminosalicylic acid (4ASA), a hydrophilic molecule, were used as model drug and coformer respectively to form cocrystals by spray drying in the presence of a third component (excipient). The solubility of the cocrystal in the excipient was measured using a thermal analysis approach. Trends in measured solubility were in agreement with those determined by calculated Hansen Solubility Parameter (HSP) values. The ratio of cocrystal components to excipient was altered and cocrystal formation at different weight ratios was assessed. Cocrystal integrity was preserved when the cocrystal components were immiscible with the excipient, based on the difference in Hansen Solubility Parameters (HSP). For immiscible systems (difference in HSP > 9.6 MPa 0.5 ), cocrystal formation occurred even when the proportion of excipient was high (90% w/w). When the excipient was partly miscible with the cocrystal components, cocrystal formation was observed post spray drying, but crystalline API and coformer were also recovered in the processed powder. An amorphous dispersion was formed when the excipient was miscible with the cocrystal components even when the proportion of excipient used as low (10% w/w excipient). For selected spray dried cocrystal-excipient systems an improvement in tableting characteristics was observed, relative to equivalent physical mixtures. Copyright © 2017 Elsevier B.V. All rights reserved.

Rational Design of Molecular Gelator - Solvent Systems Guided by Solubility Parameters

NASA Astrophysics Data System (ADS)

Lan, Yaqi

Self-assembled architectures, such as molecular gels, have attracted wide interest among chemists, physicists and engineers during the past decade. However, the mechanism behind self-assembly remains largely unknown and no capability exists to predict a priori whether a small molecule will gelate a specific solvent or not. The process of self-assembly, in molecular gels, is intricate and must balance parameters influencing solubility and those contrasting forces that govern epitaxial growth into axially symmetric elongated aggregates. Although the gelator-gelator interactions are of paramount importance in understanding gelation, the solvent-gelator specific (i.e., H-bonding) and nonspecific (dipole-dipole, dipole-induced and instantaneous dipole induced forces) intermolecular interactions are equally important. Solvent properties mediate the self-assembly of molecular gelators into their self-assembled fibrillar networks. Herein, solubility parameters of solvents, ranging from partition coefficients (logP), to Henry's law constants (HLC), to solvatochromic ET(30) parameters, to Kamlet-Taft parameters (beta, alpha and pi), to Hansen solubility parameters (deltap, deltad, deltah), etc., are correlated with the gelation ability of numerous classes of molecular gelators. Advanced solvent clustering techniques have led to the development of a priori tools that can identify the solvents that will be gelled and not gelled by molecular gelators. These tools will greatly aid in the development of novel gelators without solely relying on serendipitous discoveries.

A Systematic Approach to Solvent Selection Based on Cohesive Energy Densities in a Molecular Bulk Heterojunction System

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

Walker, Bright; Tamayo, Arnold; Duong, Duc T.

The solubilities of 3,6-bis(5-(benzofuran-2-yl)thiophen-2-yl)-2,5-bis(2-ethylhexyl)pyrrolo[3,4-c]pyrrole-1,4-dione (DPP(TBFu)₂) and [6,6]-phenyl-C₇₁-butyric acid methyl ester (PC₇₁BM) in a series of solvents are measured, and this data is used to calculate the Hansen solubility parameters of the two materials. The dispersion, polar, and H-bonding parameters of DPP(TBFu)₂ and PC₇₁BM were found to be (19.3, 4.8, 6.3) and (20.2, 5.4, 4.5) MPa{sup 1/2}, respectively, with an error of ± 0.8 MPa{sup 1/2}. Based on the solubility properties of the two materials, three new solvents (thiophene, trichloroethylene and carbon disulfide) were utilized for the DPP(TBFu)₂:PC₇₁BM system which, after device optimization, led to power conversion efficiencies up to 4.3%.

Reprint of: Effects of solution degassing on solubility, crystal growth and dissolution-Case study: Salicylic acid in methanol

NASA Astrophysics Data System (ADS)

Seidel, J.; Ulrich, J.

2017-07-01

The influence of dissolved gases on the crystallization parameter solubility, MZW, growth and dissolution rates was investigated experimentally using degassed and non-degassed (air-saturated) solutions. The results of this study show that degassing has no effect on the solubility curve of the used model substance salicylic acid (SA) in methanol (MeOH). This reveals in the assumption that a thermodynamic effect of dissolved gases can be excluded. Growth rates were measured by means of a desupersaturation method and the results indicate that the growth rates of SA are not affected by degassing. The results of the dissolution rate measurements reveal a distinct decrease in dissolution rates for non-degassed solutions compared to degassed solutions, especially, at low temperature (10 °C). To explain this phenomenon the gas solubility, represented by oxygen, in MeOH in dependence on the SA concentration was estimated by means of Hansen Solubility Parameters (HSP) [1]. It was found that the oxygen solubility decreases with increasing SA content which explains the inhibition of crystal dissolution in non-degassed solution compared to degassed solution. Moreover, this kind of 'drowing-out' mechanism would not appear in growth rate measurements, where indeed no effect of degassing could be observed.

Effects of solution degassing on solubility, crystal growth and dissolution-Case study: Salicylic acid in methanol

NASA Astrophysics Data System (ADS)

Seidel, J.; Ulrich, J.

2017-02-01

The influence of dissolved gases on the crystallization parameter solubility, MZW, growth and dissolution rates was investigated experimentally using degassed and non-degassed (air-saturated) solutions. The results of this study show that degassing has no effect on the solubility curve of the used model substance salicylic acid (SA) in methanol (MeOH). This reveals in the assumption that a thermodynamic effect of dissolved gases can be excluded. Growth rates were measured by means of a desupersaturation method and the results indicate that the growth rates of SA are not affected by degassing. The results of the dissolution rate measurements reveal a distinct decrease in dissolution rates for non-degassed solutions compared to degassed solutions, especially, at low temperature (10 °C). To explain this phenomenon the gas solubility, represented by oxygen, in MeOH in dependence on the SA concentration was estimated by means of Hansen Solubility Parameters (HSP) [1]. It was found that the oxygen solubility decreases with increasing SA content which explains the inhibition of crystal dissolution in non-degassed solution compared to degassed solution. Moreover, this kind of 'drowing-out' mechanism would not appear in growth rate measurements, where indeed no effect of degassing could be observed.

Formulation strategies for optimizing the morphology of polymeric bulk heterojunction organic solar cells: a brief review

NASA Astrophysics Data System (ADS)

Vongsaysy, Uyxing; Bassani, Dario M.; Servant, Laurent; Pavageau, Bertrand; Wantz, Guillaume; Aziz, Hany

2014-01-01

Polymeric bulk heterojunction (BHJ) organic solar cells represent one of the most promising technologies for renewable energy with a low fabrication cost. Control over BHJ morphology is one of the key factors in obtaining high-efficiency devices. This review focuses on formulation strategies for optimizing the BHJ morphology. We address how solvent choice and the introduction of processing additives affect the morphology. We also review a number of recent studies concerning prediction methods that utilize the Hansen solubility parameters to develop efficient solvent systems.

Development of novel purifiers with appropriate functional groups based on solvent polarities at bulk filtration

NASA Astrophysics Data System (ADS)

Kohyama, Tetsu; Kaneko, Fumiya; Ly, Saksatha; Hamzik, James; Jaber, Jad; Yamada, Yoshiaki

2017-03-01

Weak-polar solvents like PGMEA (Propylene Glycol Monomethyl Ether Acetate) or CHN (Cyclohexanone) are used to dissolve hydrophobic photo-resist polymers, which are challenging for traditional cleaning methods such as distillation, ion-exchange resins service or water-washing processes. This paper investigated two novel surface modifications to see their effectiveness at metal removal and to understand the mechanism. The experiments yielded effective purification methods for metal reduction, focusing on solvent polarities based on HSP (Hansen Solubility Parameters), and developing optimal purification strategies.

Establishing the importance of oil-membrane interactions on the transmembrane diffusion of physicochemically diverse compounds.

PubMed

Najib, Omaima N; Martin, Gary P; Kirton, Stewart B; Sallam, Al-Sayed; Murnane, Darragh

2016-06-15

The diffusion process through a non-porous barrier membrane depends on the properties of the drug, vehicle and membrane. The aim of the current study was to investigate whether a series of oily vehicles might have the potential to interact to varying degrees with synthetic membranes and to determine whether any such interaction might affect the permeation of co-formulated permeants: methylparaben (MP); butylparaben (BP) or caffeine (CF). The oils (isopropyl myristate (IPM), isohexadecane (IHD), hexadecane (HD), oleic acid (OA) and liquid paraffin (LP)) and membranes (silicone, high density polyethylene and polyurethane) employed in the study were selected such that they displayed a range of different structural, and physicochemical properties. Diffusion studies showed that many of the vehicles were not inert and did interact with the membranes resulting in a modification of the permeants' flux when corrected for membrane thickness (e.g. normalized flux of MP increased from 1.25±0.13μgcm(-1)h(-1) in LP to 17.94±0.25μgcm(-1)h(-1)in IPM). The oils were sorbed differently to membranes (range of weight gain: 2.2±0.2% for polyurethane with LP to 105.6±1.1% for silicone with IHD). Membrane interaction was apparently dependent upon the physicochemical properties including; size, shape, flexibility and the Hansen solubility parameter values of both the membranes and oils. Sorbed oils resulted in modified permeant diffusion through the membranes. No simple correlation was found to exist between the Hansen solubility parameters of the oils or swelling of the membrane and the normalized fluxes of the three compounds investigated. More sophisticated modelling would appear to be required to delineate and quantify the key molecular parameters of membrane, permeant and vehicle compatibility and their interactions of relevance to membrane permeation. Copyright © 2016 Elsevier B.V. All rights reserved.

Application of carrier and plasticizer to improve the dissolution and bioavailability of poorly water-soluble baicalein by hot melt extrusion.

PubMed

Zhang, Yilan; Luo, Rui; Chen, Yi; Ke, Xue; Hu, Danrong; Han, Miaomiao

2014-06-01

The objective of this study was to develop a suitable formulation for baicalein (a poorly water-soluble drug exhibiting high melting point) to prepare solid dispersions using hot melt extrusion (HME). Proper carriers and plasticizers were selected by calculating the Hansen solubility parameters, evaluating melting processing condition, and measuring the solubility of obtained melts. The characteristic of solid dispersions prepared by HME was evaluated. The dissolution performance of the extrudates was compared to the pure drug and the physical mixtures. Physicochemical properties of the extrudates were characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and Fourier transform infrared spectroscopy (FTIR). Relative bioavailability after oral administration in beagle dogs was assessed. As a result, Kollidon VA64 and Eudragit EPO were selected as two carriers; Cremophor RH was used as the plasticizer. The dissolution of all the extrudates was significantly improved. DSC and PXRD results suggested that baicalein in the extrudates was amorphous. FTIR spectroscopy revealed the interaction between drug and polymers. After oral administration, the relative bioavailability of solid dispersions with VA64 and EPO was comparative, about 2.4- and 2.9-fold greater compared to the pure drug, respectively.

Experimental study and thermodynamic modeling for determining the effect of non-polar solvent (hexane)/polar solvent (methanol) ratio and moisture content on the lipid extraction efficiency from Chlorella vulgaris.

PubMed

Malekzadeh, Mohammad; Abedini Najafabadi, Hamed; Hakim, Maziar; Feilizadeh, Mehrzad; Vossoughi, Manouchehr; Rashtchian, Davood

2016-02-01

In this research, organic solvent composed of hexane and methanol was used for lipid extraction from dry and wet biomass of Chlorella vulgaris. The results indicated that lipid and fatty acid extraction yield was decreased by increasing the moisture content of biomass. However, the maximum extraction efficiency was attained by applying equivolume mixture of hexane and methanol for both dry and wet biomass. Thermodynamic modeling was employed to estimate the effect of hexane/methanol ratio and moisture content on fatty acid extraction yield. Hansen solubility parameter was used in adjusting the interaction parameters of the model, which led to decrease the number of tuning parameters from 6 to 2. The results indicated that the model can accurately estimate the fatty acid recovery with average absolute deviation percentage (AAD%) of 13.90% and 15.00% for the two cases of using 6 and 2 adjustable parameters, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

LC-MS/MS method for the simultaneous quantification of luteolin, wedelolactone and apigenin in mice plasma using hansen solubility parameters for liquid-liquid extraction: Application to pharmacokinetics of Eclipta alba chloroform fraction.

PubMed

Cheruvu, Hanumanth Srikanth; Yadav, Navneet K; Valicherla, Guru R; Arya, Rakesh K; Hussain, Zakir; Sharma, Chetan; Arya, Kamal R; Singh, Rama K; Datta, Dipak; Gayen, Jiaur R

2018-04-01

Eclipta alba (Bhringraj) in ayurveda has been widely used as a traditional medicine for its multi-therapeutic properties for ages. Luteolin (LTL), wedelolactone (WDL) and apigenin (APG) are the three main bioactive phytochemicals present in Eclipta alba extract. However there was a lack of sensitive bioanalytical method for the pharmacokinetics of these free compounds in plasma which majorly contributes for their activities after oral administration of Eclipta alba. The present study aims to develop a sensitive, rapid and reliable liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the simultaneous estimation of mice plasma concentrations of LTL, WDL and APG using quercetin as an internal standard for the pharmacokinetic analysis. Analytes were separated on Phenomenex Luna C18 (150 × 4.6 mm, 3.0 μm) column with mobile phase containing methanol: acetonitrile (90: 10, v/v) and 0.1% formic acid in 10 mM ammonium formate buffer in the ratio of 70: 30 (v/v) in isocratic mode. Liquid-liquid extraction was optimized using Hansen solubility parameters and diethyl ether finalized as an extraction solvent for the recovery ranging from 61 to 76% for all analytes in mice plasma. The validated method has an accuracy and precision over the linearity range of 0.1-200 ng/mL with a correlation coefficient (r 2 ) of ≥0.997. The intra and inter-day assay accuracy was between 98.17 and 107% and 95.83-107.89% respectively and the intra and inter day assay precision ranged from 0.37-6.05% and 1.85-10.76%, respectively for all the analytes. This validated method can be used for future clinical investigation studies of Eclipta alba extracts. Copyright © 2018 Elsevier B.V. All rights reserved.

Method for efficient recovery of high-purity polycarbonates from electronic waste.

PubMed

Weeden, George S; Soepriatna, Nicholas H; Wang, Nien-Hwa Linda

2015-02-17

More than one million tons of polycarbonates from waste electrical and electronic equipment are consigned to landfills at an increasing rate of 3-5% per year. Recycling the polymer waste should have a major environmental impact. Pure solvents cannot be used to selectively extract polycarbonates from mixtures of polymers with similar properties. In this study, selective mixed solvents are found using guidelines from Hansen solubility parameters, gradient polymer elution chromatography, and solubility tests. A room-temperature sequential extraction process using two mixed solvents is developed to recover polycarbonates with high yield (>95%) and a similar purity and molecular weight distribution as virgin polycarbonates. The estimated cost of recovery is less than 30% of the cost of producing virgin polycarbonates from petroleum. This method would potentially reduce raw materials from petroleum, use 84% less energy, reduce emission by 1-6 tons of CO2 per ton of polycarbonates, and reduce polymer accumulation in landfills and associated environmental hazards.

Alternative Bio-Based Solvents for Extraction of Fat and Oils: Solubility Prediction, Global Yield, Extraction Kinetics, Chemical Composition and Cost of Manufacturing

PubMed Central

Sicaire, Anne-Gaëlle; Vian, Maryline; Fine, Frédéric; Joffre, Florent; Carré, Patrick; Tostain, Sylvain; Chemat, Farid

2015-01-01

The present study was designed to evaluate the performance of alternative bio-based solvents, more especially 2-methyltetrahydrofuran, obtained from crop’s byproducts for the substitution of petroleum solvents such as hexane in the extraction of fat and oils for food (edible oil) and non-food (bio fuel) applications. First a solvent selection as well as an evaluation of the performance was made with Hansen Solubility Parameters and the COnductor-like Screening MOdel for Realistic Solvation (COSMO-RS) simulations. Experiments were performed on rapeseed oil extraction at laboratory and pilot plant scale for the determination of lipid yields, extraction kinetics, diffusion modeling, and complete lipid composition in term of fatty acids and micronutrients (sterols, tocopherols and tocotrienols). Finally, economic and energetic evaluations of the process were conducted to estimate the cost of manufacturing using 2-methyltetrahydrofuran (MeTHF) as alternative solvent compared to hexane as petroleum solvent. PMID:25884332

Physico-chemical separation process of nanoparticles in cosmetic formulations

NASA Astrophysics Data System (ADS)

Retamal Marín, R. R.; Babick, F.; Stintz, M.

2017-06-01

Understanding the world of nanoparticles, especially their interactions with the environment, begins with their correct detection and successive quantification. To achieve this purpose, one needs to perform correctly developed standard operating procedures (SOPs). Furthermore, the study of nanoparticles frequently requires their characterisation in complex media (e.g. in cosmetic formulations). In this study, a set of sample preparation procedures for the detection and extraction of NMs in emulsion-based formulations is proposed and their performance for model and real-life products is discussed. A separation or extraction of lipid phases is achieved by means of organic solvents. The polarity of the lipid phases is decisive for selecting an optimum solvent. The use of the Hansen Solubility Parameters (HSP) may clearly support this decision.

Study the influence of formulation process parameters on solubility and dissolution enhancement of efavirenz solid solutions prepared by hot-melt extrusion: a QbD methodology.

PubMed

Pawar, Jaywant; Suryawanshi, Dilipkumar; Moravkar, Kailas; Aware, Rahul; Shetty, Vasant; Maniruzzaman, Mohammed; Amin, Purnima

2018-02-09

The current study investigates the dissolution rate performance of amorphous solid solutions of a poorly water-soluble drug, efavirenz (EFV), in amorphous Soluplus® (SOL) and Kollidon® VA 64 (KVA64) polymeric systems. For the purpose of the study, various formulations with varying drug loadings of 30, 50, and 70% w/w were developed via hot-melt extrusion processing and adopting a Box-Behnken design of experiment (DoE) approach. The polymers were selected based on the Hansen solubility parameter calculation and the prediction of the possible drug-polymer miscibility. In DoE experiments, a Box-Behnken factorial design was conducted to evaluate the effect of independent variables such as Soluplus® ratio (A 1 ), HME screw speed (A 2 ), and processing temperature (A 3 ), and Kollidon®VA64 ratio (B 1 ), screw speed (B 2 ), and processing temperature (B 3 ) on responses such as solubility (X 1 and Y 1 ) and dissolution rate (X 2 and Y 2 ) for both ASS [EFV:SOL] and BSS [EFV:KVA64] systems. DSC and XRD data confirmed that bulk crystalline EFV transformed to amorphous form during the HME processing. Advanced chemical analyses conducted via 2D COSY NMR, FTIR chemical imaging, AFM analysis, and FTIR showed that EFV was homogenously dispersed in the respective polymer matrices. The maximum solubility and dissolution rate was observed in formulations containing 30% EFV with both SOL and KVA64 alone. This could be attributed to the maximum drug-polymer miscibility in the optimized formulations. The actual and predicted values of both responses were found precise and close to each other.

Problems of millipound thrust measurement. The "Hansen Suspension"

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

Carta, David G.

Considered in detail are problems which led to the need and use of the 'Hansen Suspension'. Also discussed are problems which are likely to be encountered in any low level thrust measuring system. The methods of calibration and the accuracies involved are given careful attention. With all parameters optimized and calibration techniques perfected, the system was found capable of a resolution of 10 {mu} lbs. A comparison of thrust measurements made by the 'Hansen Suspension' with measurements of a less sophisticated device leads to some surprising results.

Pharmaceutical Cocrystal: An Antique and Multifaceted Approach.

PubMed

Panzade, Prabhakar S; Shendarkar, Giridhar R

2017-01-01

Pharmaceutical cocrystal is an emerging approach to tailor physicochemical and mechanical properties of drug substances. Cocrystals are composed of API and pharmaceutically acceptable coformer. It is used to address the solubility, dissolution, mechanical properties and stability of drugs. This review discusses introduction to cocrystal, preparation, and characterization, what USFDA says on cocrystal and role of Hansen solubility parameter to predict cocrystal. The effect of cocrystal on drug properties, dependence of cocrystal solubility on pH, concept of drug-drug cocrystal, and aerosil 200 as novel cocrystal former and impact of cocrystal on drug pharmacokinetic has also been presented in this review along with highly selected examples of cocrystals. Finally, how cocrystal offers an opportunity for patents is also delineated. Pharmaceutical cocrystals have ability to tailor physichochemical and mechanical properties of drug substances. It also provides opportunity for patentable invention. Therapeutic efficacy of drugs may be improved via drug-drug cocrystal. The pharmaceutical cocrystals are not fully explored and have potential for future development. Successful drug delivery can be achieved through cocrystallization. Pharmaceutical industry will be beneficial through successful cocrystallization of drug substances. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Influence of polymorphism on the surface energetics of salmeterol xinafoate crystallized from supercritical fluids.

PubMed

Tong, Henry H Y; Shekunov, Boris Yu; York, Peter; Chow, Albert H L

2002-05-01

To characterize the surface thermodynamic properties of two polymorphic forms (I and II) of salmeterol xinafoate (SX) prepared from supercritical fluids and a commercial micronized SX (form 1) sample (MSX). Inverse gas chromatographic analysis was conducted on the SX samples at 30, 40, 50, and 60 degrees C using the following probes at infinite dilution: nonpolar probes (NPs; alkane C5-C9 series); and polar probes (PPs; i.e., dichloromethane, chloroform, acetone, ethyl acetate, diethyl ether, and tetrahydrofuran). Surface thermodynamic parameters of adsorption and Hansen solubility parameters were calculated from the retention times of the probes. The free energies of adsorption (- deltaG(A)) of the three samples obtained at various temperatures follow this order: SX-II > MSX approximately/= SX-I for the NPs; and SX-II > MSX > SX-I for the PPs. For both NPs and PPs, SX-II exhibits a less negative enthalpy of adsorption (deltaH(A)) and a much less negative entropy of adsorption (ASA) than MSX and SX-I, suggesting that the high -AGA of SX-II is contributed by a considerably reduced entropy loss. The dispersive component of surface free energy (gammas(D)) is the highest for MSX but the lowest for SX-II at all temperatures studied, whereas the specific component of surface free energy of adsorption (-deltaG(A)SP) is higher for SX-II than for SX-I. That SX-II displays the highest -deltaG(A) for the NP but the lowest gammasD of all the SX samples may be explained by the additional -AGA change associated with an increased mobility of the probe molecules on the less stable and more disordered SX-II surface. The acid and base parameters, K(A) and K(D) that were derived from deltaH(A)SP reveal significant differences in the relative acid and base properties among the samples. The calculated Hansen solubility parameters (deltaD, deltap, and deltaH) indicate that the surface of SX-II is the most polar and most energetic of all the three samples in terms of specific interactions (mostly hydrogen bonding). The metastable SX-II polymorph possesses a higher surface free energy, higher surface entropy, and a more polar surface than the stable SX-I polymorph.

Nanocellular thermoplastic foam and process for making the same

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

Zhu, Lingbo; Costeux, Stephane; Patankar, Kshitish A.

Prepare a thermoplastic polymer foam having a porosity of 70% or more and at least one of: (i) an average cell size of 200 nanometers or less; and (ii) a nucleation density of at least 1.times.1015 effective nucleation sites per cubic centimeter of foamable polymer composition not including blowing agent using a foamable polymer composition containing a thermoplastic polymer selected from styrenic polymer and (meth)acrylic polymers, a blowing agent comprising at least 20 mole-percent carbon dioxide based on moles of blowing agent and an additive having a Total Hansen Solubility Parameter that differs from that of carbon dioxide by lessmore » than 2 and that is present at a concentration of 0.01 to 1.5 weight parts per hundred weight parts thermoplastic polymer.« less

Orally Disintegrating Tablets Containing Melt Extruded Amorphous Solid Dispersion of Tacrolimus for Dissolution Enhancement.

PubMed

Ponnammal, Poovizhi; Kanaujia, Parijat; Yani, Yin; Ng, Wai Kiong; Tan, Reginald B H

2018-03-16

In order to improve the aqueous solubility and dissolution of Tacrolimus (TAC), amorphous solid dispersions of TAC were prepared by hot melt extrusion with three hydrophilic polymers, Polyvinylpyrrolidone vinyl acetate (PVP VA64), Soluplus ® and Hydroxypropyl Cellulose (HPC), at a drug loading of 10% w / w . Molecular modeling was used to determine the miscibility of the drug with the carrier polymers by calculating the Hansen Solubility Parameters. Powder X-ray diffraction and differential scanning calorimetry (DSC) studies of powdered solid dispersions revealed the conversion of crystalline TAC to amorphous form. Fourier transform Infrared (FTIR) spectroscopy results indicated formation of hydrogen bond between TAC and polymers leading to stabilization of TAC in amorphous form. The extrudates were found to be stable under accelerated storage conditions for 3 months with no re-crystallization, indicating that hot melt extrusion is suitable for producing stable amorphous solid dispersions of TAC in PVP VA64, Soluplus ® and HPC. Stable solid dispersions of amorphous TAC exhibited higher dissolution rate, with the solid dispersions releasing more than 80% drug in 15 min compared to the crystalline drug giving 5% drug release in two hours. These stable solid dispersions were incorporated into orally-disintegrating tablets in which the solid dispersion retained its solubility, dissolution and stability advantage.

Orally Disintegrating Tablets Containing Melt Extruded Amorphous Solid Dispersion of Tacrolimus for Dissolution Enhancement

PubMed Central

Ponnammal, Poovizhi; Kanaujia, Parijat; Ng, Wai Kiong; Tan, Reginald B. H.

2018-01-01

In order to improve the aqueous solubility and dissolution of Tacrolimus (TAC), amorphous solid dispersions of TAC were prepared by hot melt extrusion with three hydrophilic polymers, Polyvinylpyrrolidone vinyl acetate (PVP VA64), Soluplus® and Hydroxypropyl Cellulose (HPC), at a drug loading of 10% w/w. Molecular modeling was used to determine the miscibility of the drug with the carrier polymers by calculating the Hansen Solubility Parameters. Powder X-ray diffraction and differential scanning calorimetry (DSC) studies of powdered solid dispersions revealed the conversion of crystalline TAC to amorphous form. Fourier transform Infrared (FTIR) spectroscopy results indicated formation of hydrogen bond between TAC and polymers leading to stabilization of TAC in amorphous form. The extrudates were found to be stable under accelerated storage conditions for 3 months with no re-crystallization, indicating that hot melt extrusion is suitable for producing stable amorphous solid dispersions of TAC in PVP VA64, Soluplus® and HPC. Stable solid dispersions of amorphous TAC exhibited higher dissolution rate, with the solid dispersions releasing more than 80% drug in 15 min compared to the crystalline drug giving 5% drug release in two hours. These stable solid dispersions were incorporated into orally-disintegrating tablets in which the solid dispersion retained its solubility, dissolution and stability advantage. PMID:29547585

Enhanced in vivo absorption of CB-1 antagonist in rats via solid solutions prepared by hot-melt extrusion.

PubMed

Ranzani, L S; Font, J; Galimany, F; Santanach, A; Gomez-Gomar, A M; Casadevall, G; Gryczke, A

2011-06-01

The aim of the present work was to investigate in vitro dissolution properties of three binary solid solutions prepared by a hot-melt extrusion (HME) process with vinyl pirrolidone--vinyl acetate copolymer (Kollidon VA 64), ethyl acrylate, methyl methacrylate polymer (Eudragit E) polyetilenglicol 8000 (PEG 8000) with a cannabinoid type 1 (CB-1) antagonist. Hansen solubility parameters were calculated from the chemical structures of the drug and the individual polymers in order to predict miscibility. Solid state characterizations of drug substance, physical blends and HME formulations were performed with differential scanning calorimetry. The dissolution testing conducted under sink conditions revealed that the dissolution rate of HME formulations improved around 1.8-fold vs drug substance. Supersaturation dissolution study demonstrated that HME formulations composed by Eudragit E and Kollidon VA64 increased drug solubility between 30- and 35-fold, respectively comparing to the drug substance. Physical and chemical stability of formulations were studied at 40°C/75%HR with open dish during 15 days. The formulation composed by the drug and Eudragit E at 10:90 was evaluated for in vivo drug absorption in male Wistar-Hannover rats and it was found to increase CB-1 absorption threefold greater than pure drug oral suspension.

Considering the filler network as a third phase in polymer/CNT nanocomposites to predict the tensile modulus using Hashin-Hansen model

NASA Astrophysics Data System (ADS)

Kim, Sanghoon; Jamalzadeh, Navid; Zare, Yasser; Hui, David; Rhee, Kyong Yop

2018-07-01

In this paper, a conventional Hashin-Hansen model is developed to analyze the tensile modulus of polymer/CNT nanocomposites above the percolation threshold. This model for composites containing dispersed particles utilizes the aspect ratio of the nanofiller (α), the number of nanotubes per unit area (N), the percolation threshold (φp) and the modulus of the filler network (EN), assuming that the filler network constitutes a third phase in the nanocomposites. The experimental results and the predictions agree well, verifying the proposed relations between the modulus and the other parameters in the Hashin-Hansen model. Moreover, large values of "α", "N" and "EN" result in an improved modulus of the polymer/CNT nanocomposites, while a low percolation threshold results in a high modulus.

Nailfold capillaroscopy in leprosy.

PubMed

Lima, Adma Silva de; Pizzol, Vanessa Irusta Dal; Fritsch, Scheila; Fonseca, Gabriela Poglia; Mulinari-Brenner, Fabiane Andrade; Muller, Carolina de Souza; Ottoboni, Vanessa Cristhine Dalombo

2016-01-01

Due to mounting evidences of interaction between Hansen's bacilli with endothelial cells and the paucity of studies addressing the presence of nailfold capillaroscopic alterations in patients with Hansen's disease, a study was carried out in order to verify the presence of capillaroscopic alterations in patients with leprosy in its various forms and its correlation with clinical parameters. Ten patients were evaluated at a specialized university service. Sixty percent of those had some capillaroscopic change, such as micro-hemorrhages, ectatic, bushy and corkscrew capillaries. Such changes were unspecific, which suggests there is not a specific pattern for this disease.

Ciprofloxacin hydrochloride-loaded glyceryl monostearate nanoparticle: factorial design of Lutrol F68 and Phospholipon 90G.

PubMed

Shah, Malay; Agrawal, Yadvendra

2012-01-01

This investigation was undertaken to develop glyceryl monostearate (Geleol)-based solid lipid nanoparticles (SLNs) of a hydrophilic drug ciprofloxacin HCl. Hansen's solubility parameter study was carried out in screening of a suitable carrier and solvent system. Subsequently, SLNs were prepared by solvent diffusion evaporation method and investigated for particle size, polydispersity index (PDI), zeta potential (ZP), entrapment efficiency (EE) and drug release behaviour. Variations in SLN composition resulted in particle sizes between 170 and 810 nm and ZPs between 8 and 14 mV. The maximum EE was found to be 26.3% with particle size of 188.8 nm. SLN can sustain the release of drug for up to 15 h and it shows Higuchi matrix model as the best-fitted model. SLNs were stable without aggregation of particles under storage conditions. The results of this study provide the framework for further study involving the SLN formulation for hydrophilic drug molecule.

Tunable Physical Properties of Ethylcellulose/Gelatin Composite Nanofibers by Electrospinning.

PubMed

Liu, Yuyu; Deng, Lingli; Zhang, Cen; Feng, Fengqin; Zhang, Hui

2018-02-28

In this work, the ethylcellulose/gelatin blends at various weight ratios in water/ethanol/acetic acid solution were electrospun to fabricate nanofibers with tunable physical properties. The solution compatibility was predicted based on Hansen solubility parameters and evaluated by rheological measurements. The physical properties were characterized by scanning electron microscopy, porosity, differential scanning calorimetry, thermogravimetry, Fourier transform infrared spectroscopy, and water contact angle. Results showed that the entangled structures among ethylcellulose and gelatin chains through hydrogen bonds gave rise to a fine morphology of the composite fibers with improved thermal stability. The fibers with higher gelatin ratio (75%), possessed hydrophilic surface (water contact angle of 53.5°), and adequate water uptake ability (1234.14%), while the fibers with higher ethylcellulose proportion (75%) tended to be highly water stable with a hydrophobic surface (water contact angle of 129.7°). This work suggested that the composite ethylcellulose/gelatin nanofibers with tunable physical properties have potentials as materials for bioactive encapsulation, food packaging, and filtration applications.

Nailfold capillaroscopy in leprosy*

PubMed Central

de Lima, Adma Silva; Pizzol, Vanessa Irusta dal; Fritsch, Scheila; Fonseca, Gabriela Poglia; Mulinari-Brenner, Fabiane Andrade; Muller, Carolina de Souza; Ottoboni, Vanessa Cristhine Dalombo

2016-01-01

Due to mounting evidences of interaction between Hansen's bacilli with endothelial cells and the paucity of studies addressing the presence of nailfold capillaroscopic alterations in patients with Hansen's disease, a study was carried out in order to verify the presence of capillaroscopic alterations in patients with leprosy in its various forms and its correlation with clinical parameters. Ten patients were evaluated at a specialized university service. Sixty percent of those had some capillaroscopic change, such as micro-hemorrhages, ectatic, bushy and corkscrew capillaries. Such changes were unspecific, which suggests there is not a specific pattern for this disease. PMID:27828654

42 CFR 32.91 - Purchase of services for Hansen's disease patients.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Purchase of services for Hansen's disease patients... MEDICAL CARE AND EXAMINATIONS MEDICAL CARE FOR PERSONS WITH HANSEN'S DISEASE AND OTHER PERSONS IN EMERGENCIES Persons with Hansen's Disease § 32.91 Purchase of services for Hansen's disease patients. Hansen's...

42 CFR 32.91 - Purchase of services for Hansen's disease patients.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 42 Public Health 1 2011-10-01 2011-10-01 false Purchase of services for Hansen's disease patients... MEDICAL CARE AND EXAMINATIONS MEDICAL CARE FOR PERSONS WITH HANSEN'S DISEASE AND OTHER PERSONS IN EMERGENCIES Persons with Hansen's Disease § 32.91 Purchase of services for Hansen's disease patients. Hansen's...

42 CFR 32.91 - Purchase of services for Hansen's disease patients.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 42 Public Health 1 2014-10-01 2014-10-01 false Purchase of services for Hansen's disease patients... MEDICAL CARE AND EXAMINATIONS MEDICAL CARE FOR PERSONS WITH HANSEN'S DISEASE AND OTHER PERSONS IN EMERGENCIES Persons with Hansen's Disease § 32.91 Purchase of services for Hansen's disease patients. Hansen's...

42 CFR 32.91 - Purchase of services for Hansen's disease patients.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 42 Public Health 1 2012-10-01 2012-10-01 false Purchase of services for Hansen's disease patients... MEDICAL CARE AND EXAMINATIONS MEDICAL CARE FOR PERSONS WITH HANSEN'S DISEASE AND OTHER PERSONS IN EMERGENCIES Persons with Hansen's Disease § 32.91 Purchase of services for Hansen's disease patients. Hansen's...

42 CFR 32.91 - Purchase of services for Hansen's disease patients.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 42 Public Health 1 2013-10-01 2013-10-01 false Purchase of services for Hansen's disease patients... MEDICAL CARE AND EXAMINATIONS MEDICAL CARE FOR PERSONS WITH HANSEN'S DISEASE AND OTHER PERSONS IN EMERGENCIES Persons with Hansen's Disease § 32.91 Purchase of services for Hansen's disease patients. Hansen's...

Reduced toxicity polyester resins and microvascular pre-preg tapes for advanced composites manufacturing

NASA Astrophysics Data System (ADS)

Poillucci, Richard

Advanced composites manufacturing broadly encapsulates topics ranging from matrix chemistries to automated machines that lay-up fiber-reinforced materials. Environmental regulations are stimulating research to reduce matrix resin formulation toxicity. At present, composites fabricated with polyester resins expose workers to the risk of contact with and inhalation of styrene monomer, which is a potential carcinogen, neurotoxin, and respiratory irritant. The first primary goal of this thesis is to reduce the toxicity associated with polyester resins by: (1) identification of potential monomers to replace styrene, (2) determination of monomer solubility within the polyester, and (3) investigation of approaches to rapidly screen a large resin composition parameter space. Monomers are identified based on their ability to react with polyester and their toxicity as determined by the Globally Harmonized System (GHS) and a green screen method. Solubilities were determined by the Hoftyzer -- Van Krevelen method, Hansen solubility parameter database, and experimental mixing of monomers. A combinatorial microfluidic mixing device is designed and tested to obtain distinct resin compositions from two input chemistries. The push for safer materials is complemented by a thrust for multifunctional composites. The second primary goal of this thesis is to design and implement the manufacture of sacrificial fiber materials suitable for use in automated fiber placement of microvascaular multifunctional composites. Two key advancements are required to achieve this goal: (1) development of a roll-to-roll method to place sacrificial fibers onto carbon fiber pre-preg tape; and (2) demonstration of feasible manufacture of microvascular carbon fiber plates with automated fiber placement. An automated method for placing sacrificial fibers onto carbon fiber tapes is designed and a prototype implemented. Carbon fiber tows with manual placement of sacrificial fibers is implemented within an automated fiber placement machine and the successful fabrication of a carbon fiber plate with an integrated microvascular channel is demonstrated.

Solvent-induced dimensional changes in EDTA-demineralized dentin matrix.

PubMed

Pashley, D H; Agee, K A; Nakajima, M; Tay, F R; Carvalho, R M; Terada, R S; Harmon, F J; Lee, W K; Rueggeberg, F A

2001-08-01

The purpose of this study was to test the null hypothesis that the re-expansion of dried matrix and the shrinkage of moist, demineralized dentin is not influenced by polar solvents. Dentin disks were prepared from midcoronal dentin of extracted human third molars. After complete demineralization in 0.5M of EDTA (pH 7), the specimens were placed in the well of a device that measures changes in matrix height in real time. Dry, collapsed matrices were created by blowing dry N(2) on the specimens until they shrank to a stable plateau. Polar solvents [water, methanol, ethanol, n-propanol, n-butanol, formamide, ethylene glycol, hydroxyethyl methacrylate (HEMA), or mixtures of water-HEMA] as model primers then were added and the degree of re-expansion measured. These same solvents also were applied to moist, expanded matrices and the solvent-induced shrinkages measured. Regression analysis was used to test the correlations between matrix height and Hansen's dispersive, polar, hydrogen bonding, and total solubility parameters (delta(d), delta(p), delta(h), delta(t)). The results indicate that water-free polar solvents of low hydrogen bonding (H-bond) ability (e.g., neat HEMA) do not re-expand dried matrices and that they shrink moist matrices. When HEMA was mixed with progressively higher water concentrations, the model water-HEMA primers expanded the dried matrix in proportion to their water concentrations and they produced less shrinkage of moist matrices. Solvents with higher H-bonding capacities (methanol, ethanol, ethylene glycol, formamide, and water) re-expanded the dried matrix in proportion to their solubility parameters for H-bonding (delta(h)). They also induced small transient shrinkages of moist matrices, which slowly re-expanded. The results require rejection of the null hypothesis. Copyright 2001 John Wiley & Sons, Inc. J Biomed Mater Res 56: 273-281, 2001

FTIR Imaging Coupled with Multivariate Analysis for Study of Initial Diffusion of Different Solvents in Cellulose Acetate Butyrate Films

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

Lindblad, M.S.; Keyes, B.; Gedvilas, L.

Fourier transform infrared (FTIR) spectroscopic imaging was used to study the initial diffusion of different solvents in cellulose acetate butyrate (CAB) films containing different amounts of acetyl and butyryl substituents. Different solvents and solvent/non-solvent mixtures were also studied. The FTIR imaging system allowed acquisition of sequential images of the CAB films as solvent penetration proceeded without disturbing the system. The interface between the non-swollen polymer and the initial swelling front could be identified using multivariate data analysis tools. For a series of ketone solvents the initial diffusion coefficients and diffusion rates could be quantified and were found to be relatedmore » to the polar and hydrogen interaction parameters in the Hansen solubility parameters of the solvents. For the solvent/non-solvent system the initial diffusion rate decreased less than linearly with the weight-percent of non-solvent present in the solution, which probably was due to the swelling characteristic of the non-solvent. For a given solvent, increasing the butyryl content of the CAB increased the initial diffusion rate. Increasing the butyryl content from 17 wt.% butyryl to 37 wt.% butyryl produced a considerably larger increase in initial diffusion rate compared to an increase in butyryl content from 37 wt.% to 50 wt.% butyryl.« less

Graphene and poly(methyl methacrylate) composite laminates on flexible substrates for volatile organic compound detection

NASA Astrophysics Data System (ADS)

Rattanabut, Chanoknan; Wongwiriyapan, Winadda; Muangrat, Worawut; Bunjongpru, Win; Phonyiem, Mayuree; Song, Young Jae

2018-04-01

In this paper, we present a gas sensor for volatile organic compound (VOC) detection based on graphene and poly(methyl methacrylate) (GR/PMMA) composite laminates fabricated using CVD-grown graphene. Graphene was transferred to a poly(ethylene terephthalate) (PET) substrate by PMMA-supported wet transfer process without PMMA removal in order to achieve the deposition of GR/PMMA composite laminates on PET. The GR/PMMA and graphene sensors show completely different sensitivities to VOC vapors. The GR/PMMA and graphene sensors showed the highest sensitivities to dichloromethane (DCM). The response of the GR/PMMA sensor to DCM was 3 times higher than that of the graphene sensor but the GR/PMMA sensor hardly responded to acetone, chloroform, or benzene. The sensing mechanism of the graphene sensor can be based on the dielectric constant of VOCs, the size of VOC molecule, and electron hopping effects on defect graphene, while that of the GR/PMMA sensor can be explained in terms of the polymer swelling owing to the Hansen solubility parameter.

Continuous production of itraconazole-based solid dispersions by hot melt extrusion: Preformulation, optimization and design space determination.

PubMed

Thiry, Justine; Lebrun, Pierre; Vinassa, Chloe; Adam, Marine; Netchacovitch, Lauranne; Ziemons, Eric; Hubert, Philippe; Krier, Fabrice; Evrard, Brigitte

2016-12-30

The purpose of this work was to increase the solubility and the dissolution rate of itraconazole, which was chosen as the model drug, by obtaining an amorphous solid dispersion by hot melt extrusion. Therefore, an initial preformulation study was conducted using differential scanning calorimetry, thermogravimetric analysis and Hansen's solubility parameters in order to find polymers which would have the ability to form amorphous solid dispersions with itraconazole. Afterwards, the four polymers namely Kollidon ® VA64, Kollidon ® 12PF, Affinisol ® HPMC and Soluplus ® , that met the set criteria were used in hot melt extrusion along with 25wt.% of itraconazole. Differential scanning confirmed that all four polymers were able to amorphize itraconazole. A stability study was then conducted in order to see which polymer would keep itraconazole amorphous as long as possible. Soluplus ® was chosen and, the formulation was fine-tuned by adding some excipients (AcDiSol ® , sodium bicarbonate and poloxamer) during the hot melt extrusion process in order to increase the release rate of itraconazole. In parallel, the range limits of the hot melt extrusion process parameters were determined. A design of experiment was performed within the previously defined ranges in order to optimize simultaneously the formulation and the process parameters. The optimal formulation was the one containing 2.5wt.% of AcDiSol ® produced at 155°C and 100rpm. When tested with a biphasic dissolution test, more than 80% of itraconazole was released in the organic phase after 8h. Moreover, this formulation showed the desired thermoformability value. From these results, the design space around the optimum was determined. It corresponds to the limits within which the process would give the optimized product. It was observed that a temperature between 155 and 170°C allowed a high flexibility on the screw speed, from about 75 to 130rpm. Copyright © 2016 Elsevier B.V. All rights reserved.

Raymond Hansen | NREL

Science.gov Websites

Raymond Hansen Photo of Raymond Hansen Raymond Hansen Industrial Research Equipment Technician Pyrolysis Areas of Expertise Industrial equipment fabrication specialist Pilot plant operator/trainer Education Industrial Science Program, Red Rocks Community College, 2006-present Professional Experience

VizieR Online Data Catalog: RPA Southern Pilot Search of 107 Stars (Hansen+, 2018)

NASA Astrophysics Data System (ADS)

Hansen, T. T.; Holmbeck, E. M.; Beers, T. C.; Placco, V. M.; Roederer, I. U.; Frebel, A.; Sakari, C. M.; Simon, J. D.; Thompson, I. B.

2018-03-01

Complete equivalent width measurements of FeI and FeII lines for all stars in our sample used to derive spectroscopic stellar parameters. Also included are the derived abundances for each line. (2 data files).

Peter Andreas Hansen and the astronomical community - a first investigation of the Hansen papers. (German Title: Peter Andreas Hansen und die astronomische Gemeinschaft - eine erste Auswertung des Hansen-Nachlasses. )

NASA Astrophysics Data System (ADS)

Schwarz, Oliver; Strumpf, Manfred

The literary assets of Peter Andreas Hansen are deposited in the Staatsarchiv Hamburg, the Forschungs- und Landesbibliothek Gotha and the Thüringer Staatsarchiv Gotha. They were never systematically investigated. We present here some results of a first evaluation. It was possible to reconstruct the historical events with regard to the maintenance of the Astronomische Nachrichten and the Altona observatory in 1854. Hansen was a successful teacher for many young astronomers. His way of stimulating the evolution of astronomy followed Zach's tradition.

Development and study of the displaced foam dispersion methodology for the manufacture of multiscale/hybrid composites

NASA Astrophysics Data System (ADS)

McCrary-Dennis, Micah C. L.

Incorporating nanostructured functional constituents within polymers has become extensive in processes and products for manufacturing composites. The conception of carbon nanotubes (CNTs) and their heralded attributes yielding property enhancements to the carrier system is leading many industries and research endeavors. Displaced Foam Dispersion (DFD) methodology is a novel and effective approach to facilitating the incorporation of CNTs within fiber reinforced polymer composites (FRPC). The methodology consists of six separate solubility phases that lead to the manufacture of CNT-FRPCs (also termed hybrid/multiscale composites). This study was primarily initiated to characterize the interaction parameters of nanomaterials (multiwall carbon nanotubes), polymers (polystyrene), and solvents (dimethyl formamide (DMF) and acetone) in the current paradigm of the DFD materials manufacture. Secondly, we sought to illustrate the theoretical potential for the methodology to be used in conjunction with other nanomaterial-polymer-solvent systems. Herein, the theory of Hansen's solubility parameters (HSP) is employed to explain the DFD constituents manufacturing combination parameters and aid in the explanation of the experimental results. The results illustrate quantitative values for the relative energy differences between each polymer-solvent system. Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were used to characterize the multiwalled carbon nanotubes (MWCNTs) in each of the solubility stages and culminates with an indication of good dispersion potential in the final multiscale composite. Additionally, acetone absorption, evaporation mass loss and retention are reported for the sorbed plasticized PS-CNT (CNTaffy) nanocomposites that has successfully achieved up through approximately 60 weight percent loading. The findings indicate that as CNT loading percentage increases the acetone absorbency also increases, but the materials retention of acetone over time decreases. This directly influences the manufacturability of the porous polymer nanocomposite (P-PNC) in the DFD methodology. Localized interlaminar CNT enrichment was achieved through 60 wt. % loading within the P-PNC and verified under two-electrode electrical conductivity testing of the final multiscale composite. The electrical properties of low weight percent (approximately 0.15 - 2.5 wt. %) nanomaterials show a decreasing trend in the materials' resistivity that indicates the ability to become increasingly conductive with increasing CNT loadings. Finally, the mechanical properties will show evidence of toughness, increased strain to failure, and the potential for greater energy absorption.

Compatibility Study for Plastic, Elastomeric, and Metallic Fueling Infrastructure Materials Exposed to Aggressive Formulations of Ethanol-blended Gasoline

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

Kass, Michael D; Pawel, Steven J; Theiss, Timothy J

In 2008 Oak Ridge National Laboratory began a series of experiments to evaluate the compatibility of fueling infrastructure materials with intermediate levels of ethanol-blended gasoline. Initially, the focus was elastomers, metals, and sealants, and the test fuels were Fuel C, CE10a, CE17a and CE25a. The results of these studies were published in 2010. Follow-on studies were performed with an emphasis on plastic (thermoplastic and thermoset) materials used in underground storage and dispenser systems. These materials were exposed to test fuels of Fuel C and CE25a. Upon completion of this effort, it was felt that additional compatibility data with higher ethanolmore » blends was needed and another round of experimentation was performed on elastomers, metals, and plastics with CE50a and CE85a test fuels. Compatibility of polymers typically relates to the solubility of the solid polymer with a solvent. It can also mean susceptibility to chemical attack, but the polymers and test fuels evaluated in this study are not considered to be chemically reactive with each other. Solubility in polymers is typically assessed by measuring the volume swell of the polymer exposed to the solvent of interest. Elastomers are a class of polymers that are predominantly used as seals, and most o-ring and seal manufacturers provide compatibility tables of their products with various solvents including ethanol, toluene, and isooctane, which are components of aggressive oxygenated gasoline as described by the Society of Automotive Engineers (SAE) J1681. These tables include a ranking based on the level of volume swell in the elastomer associated with exposure to a particular solvent. Swell is usually accompanied by a decrease in hardness (softening) that also affects performance. For seal applications, shrinkage of the elastomer upon drying is also a critical parameter since a contraction of volume can conceivably enable leakage to occur. Shrinkage is also indicative of the removal of one or more components of the elastomers (by the solvent). This extraction of additives can negatively change the properties of the elastomer, leading to reduced performance and durability. For a seal application, some level of volume swell is acceptable, since the expansion will serve to maintain a seal. However, the acceptable level of swell is dependent on the particular application of the elastomer product. It is known that excessive swell can lead to unacceptable extrusion of the elastomer beyond the sealed interface, where it becomes susceptible to damage. Also, since high swell is indicative of high solubility, there is a heightened potential for fluid to seep through the seal and into the environment. Plastics, on the other hand, are used primarily in structural applications, such as solid components, including piping and fluid containment. Volume change, especially in a rigid system, will create internal stresses that may negatively affect performance. In order to better understand and predict the compatibility for a given polymer type and fuel composition, an analysis based on Hansen solubility theory was performed for each plastic and elastomer material. From this study, the solubility distance was calculated for each polymer material and test fuel combination. Using the calculated solubility distance, the ethanol concentration associated with peak swell and overall extent of swell can be predicted for each polymer. The bulk of the material discussion centers on the plastic materials, and their compatibility with Fuel C, CE25a, CE50a, and CE85a. The next section of this paper focuses on the elastomer compatibility with the higher ethanol concentrations with comparison to results obtained previously for the lower ethanol levels. The elastomers were identical to those used in the earlier study. Hansen solubility theory is also applied to the elastomers to provide added interpretation of the results. The final section summarizes the performance of the metal coupons.« less

Delayed neutron spectral data for Hansen-Roach energy group structure

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

Campbell, J.M.; Spriggs, G.D.

A detailed knowledge of delayed neutron spectra is important in reactor physics. It not only allows for an accurate estimate of the effective delayed neutron fraction {beta}{sub eff} but also is essential to calculating important reactor kinetic parameters, such as effective group abundances and the ratio of {beta}{sub eff} to the prompt neutron generation time. Numerous measurements of delayed neutron spectra for various delayed neutron precursors have been performed and reported in the literature. However, for application in reactor physics calculations, these spectra are usually lumped into one of the traditional six groups of delayed neutrons in accordance to theirmore » half-lives. Subsequently, these six-group spectra are binned into energy intervals corresponding to the energy intervals of a chosen nuclear cross-section set. In this work, the authors present a set of delayed neutron spectra that were formulated specifically to match Keepin`s six-group parameters and the 16-energy-group Hansen-Roach cross sections.« less

Revision of the Neotropical water scavenger beetle genus Quadriops Hansen, 1999 (Coleoptera, Hydrophilidae, Acidocerinae)

PubMed Central

Girón, Jennifer C.; Short, Andrew Edward Z.

2017-01-01

Abstract The genus Quadriops Hansen, 1999 is revised and redescribed. The genus is found to contain six species, including two that are here described as new: Quadriops clusia sp. n. (Brazil, Guyana, Suriname) and Q. acroreius sp. n. (Suriname, French Guiana). Two species are found to be junior subjective synonyms of Q. depressus Hansen, 1999: Q. amazonensis García, 2000, syn. n. and Q. politus Hansen, 1999, syn. n. The male of Q. similaris Hansen, 1999 is described for the first time. New records are provided for Q. dentatus Hansen, 1999, Q. reticulatus Hansen, 1999, and Q. similaris. All species are described and illustrated in detail. Most species are confirmed as having a terrestrial way of life, with several species being found in rotten fruits, sap flows, and dead wood. Furthermore, we discuss ecological trends of the species given their collecting information. PMID:29118615

W. W. Hansen, Microwave Physics, and Silicon Valley

NASA Astrophysics Data System (ADS)

Leeson, David

2009-03-01

The Stanford physicist W. W. Hansen (b. 1909, AB '29 and PhD '32, MIT post-doc 1933-4, Prof. physics '35-'49, d. 1949) played a seminal role in the development of microwave electronics. His contributions underlay Silicon Valley's postwar ``microwave'' phase, when numerous companies, acknowledging their unique scientific debt to Hansen, flourished around Stanford University. As had the prewar ``radio'' companies, they furthered the regional entrepreneurial culture and prepared the ground for the later semiconductor and computer developments we know as Silicon Valley. In the 1930's, Hansen invented the cavity resonator. He applied this to his concept of the radio-frequency (RF) linear accelerator and, with the Varian brothers, to the invention of the klystron, which made microwave radar practical. As WWII loomed, Hansen was asked to lecture on microwaves to the physicists recruited to the MIT Radiation Laboratory. Hansen's ``Notes on Microwaves,'' the Rad Lab ``bible'' on the subject, had a seminal impact on subsequent works, including the Rad Lab Series. Because of Hansen's failing health, his postwar work, and MIT-Stanford rivalries, the Notes were never published, languishing as an underground classic. I have located remaining copies, and will publish the Notes with a biography honoring the centenary of Hansen's birth. After the war, Hansen founded Stanford's Microwave Laboratory to develop powerful klystrons and linear accelerators. He collaborated with Felix Bloch in the discovery of nuclear magnetic resonance. Hansen experienced first-hand Stanford's evolution from its depression-era physics department to corporate, then government funding. Hansen's brilliant career was cut short by his death in 1949, after his induction in the National Academy of Sciences. His ideas were carried on in Stanford's two-mile long linear accelerator and the development of Silicon Valley.

42 CFR 22.1 - Duty at a station of the Service devoted to the care of Hansen's disease patients; additional pay.

Code of Federal Regulations, 2010 CFR

2010-10-01

... care of Hansen's disease patients; additional pay. 22.1 Section 22.1 Public Health PUBLIC HEALTH... Hansen's Disease Duty by Personnel Other Than Commissioned Officers § 22.1 Duty at a station of the Service devoted to the care of Hansen's disease patients; additional pay. (a) Non-commissioned officers...

42 CFR 22.1 - Duty at a station of the Service devoted to the care of Hansen's disease patients; additional pay.

Code of Federal Regulations, 2011 CFR

2011-10-01

... care of Hansen's disease patients; additional pay. 22.1 Section 22.1 Public Health PUBLIC HEALTH... Hansen's Disease Duty by Personnel Other Than Commissioned Officers § 22.1 Duty at a station of the Service devoted to the care of Hansen's disease patients; additional pay. (a) Non-commissioned officers...

42 CFR 22.1 - Duty at a station of the Service devoted to the care of Hansen's disease patients; additional pay.

Code of Federal Regulations, 2012 CFR

2012-10-01

... care of Hansen's disease patients; additional pay. 22.1 Section 22.1 Public Health PUBLIC HEALTH... Hansen's Disease Duty by Personnel Other Than Commissioned Officers § 22.1 Duty at a station of the Service devoted to the care of Hansen's disease patients; additional pay. (a) Non-commissioned officers...

42 CFR 22.1 - Duty at a station of the Service devoted to the care of Hansen's disease patients; additional pay.

Code of Federal Regulations, 2013 CFR

2013-10-01

... care of Hansen's disease patients; additional pay. 22.1 Section 22.1 Public Health PUBLIC HEALTH... Hansen's Disease Duty by Personnel Other Than Commissioned Officers § 22.1 Duty at a station of the Service devoted to the care of Hansen's disease patients; additional pay. (a) Non-commissioned officers...

42 CFR 22.1 - Duty at a station of the Service devoted to the care of Hansen's disease patients; additional pay.

Code of Federal Regulations, 2014 CFR

2014-10-01

... care of Hansen's disease patients; additional pay. 22.1 Section 22.1 Public Health PUBLIC HEALTH... Hansen's Disease Duty by Personnel Other Than Commissioned Officers § 22.1 Duty at a station of the Service devoted to the care of Hansen's disease patients; additional pay. (a) Non-commissioned officers...

Comparative role of 20% cord blood serum and 20% autologous serum in dry eye associated with Hansen's disease: a tear proteomic study.

PubMed

Mukhopadhyay, Somnath; Sen, Swarnali; Datta, Himadri

2015-01-01

To compare the role of topically applied serum therapy with preservative-free artificial tear (AT) drops in patients with moderate to severe dry eye in Hansen's disease along with change in tear protein profile. 144 consecutive patients were randomly divided into three groups. After a baseline examination of clinical parameters, each of the patients received designated modality of topical therapy six times a day for 6 weeks. Post-treatment documentation of clinical parameters was done at 6 weeks, and then at 12 weeks after discontinuation of topical therapy. Analysis of three tear proteins using gel electrophoresis (sodium dodecyl sulfate polyacrylamide gel electrophoresis) was done at baseline, at the first and second post-treatment visits. In the cord blood serum (CBS) group, except for McMonnies score and staining score, all other clinical parameters showed continued improvement in the first and second post-treatment analyses. In the autologous serum (ALS) group, all the clinical parameters except Schirmer's I showed significant improvement in the first post-treatment analysis .This was sustained at a significant level in the second analysis except for tear film break-up time (TBUT) and conjunctival impression cytology grading. In the AT group, all the parameters improved at a non-significant level except for TBUT in the first analysis. In the next analysis, apart from McMonnies score and TBUT, other clinical parameters did not improve. In the ALS and CBS groups, tear lysozyme, lactoferrin levels improved in both post-treatment measurements (statistically insignificant).Total tear protein continued to increase at statistically significant levels in the first and second post-treatment analyses in the CBS group and at a statistically insignificant level in the ALS group. In the AT group, the three tear proteins continued to decrease in both the analyses. In moderate to severe dry eye in Hansen's disease, serum therapy in comparison with AT drops, improves clinical parameters and causes betterment in tear protein profile. CTRI/2013/07/003802. 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 study on the physicochemical properties of hydroalcoholic solutions to improve the direct exfoliation of natural graphite down to few-layers graphene

NASA Astrophysics Data System (ADS)

Fedi, Filippo; Miglietta, Maria Lucia; Polichetti, Tiziana; Ricciardella, Filiberto; Massera, Ettore; Ninno, Domenico; Di Francia, Girolamo

2015-03-01

Straightforward methods to produce pristine graphene flakes in large quantities are based on the liquid-phase exfoliation processes. These one-step physical transformations of graphite into graphene offer many unique advantages. To date, a large number of liquids have been employed as exfoliation media exploiting their thermodynamic and chemical features as compared to those of graphene. Here, we pursued the goal of realizing water based mixtures to exfoliate graphite and disperse graphene without the aid of surfactants. To this aim, aqueous mixtures with suitable values of surface tension and Hansen solubility parameters (HSPs), were specifically designed and used. The very high water surface tension was decreased by the addition of solvents with lower surface tensions such as alcohols, obtaining, in this way, more favourable HSP distances. The specific role of each of these thermodynamic features was finally investigated. The results showed that the designed hydroalcoholic solutions were effective in both the graphite exfoliation and dispersion without the addition of any surfactants or other stabilizing agents. Stable graphene suspensions were obtained at concentration comparable to those produced with low-boiling solvents and water/surfactants.

A Modern History of 'Imperial Medicine' Surrounding Hansen's Disease: Strategies to Manage Public Opinion in Modern Japanese Media.

PubMed

Seo, Gijae

2017-12-01

The purpose of this study is to understand the reality of imperial medicine by exploring the strategic attitude of the Japanese authority targeting the public who were not patients of Hansen's disease. For this purpose, this study examines the mass media data related to Hansen's disease published in Korea and Japan during the Japanese colonial rule. Research on Hansen's disease can be divided into medical, sociohistorical, social welfare, and human rights approach. There are medical studies and statistics on the dissemination of medical information about Hansen's disease and management measures, the history of the management of the disease, guarantee of the rights of the patients and the welfare environment, and studies on the autobiographical, literary writings and oral statements on the life and psychological conflicts of the patients. Among existing research, the topics of the study on Hansen's disease under the Japanese colonial rule include the history of the Sorokdo Island Sanatorium, investigation on the forced labor of the patients in the island, human rights violations against the patients, oral memoirs of the patients and doctors who practiced at that time. All of these studies are important achievements regarding the research on the patients. An important study of Hansen's disease in modern Japan is the work of Hujino Utaka, which introduces the isolation of and discrimination against the patients of Hansen's disease. Hujino Utaka's study examines the annihilation of people with infectious diseases in Japan and its colonies by the imperial government, which was the consequence of the imperial medical policies, and reports on the isolation of Hansen's disease patients during the war. Although these researches are important achievements in the study of Hansen's disease in modernity, their focus has mainly been on the history of isolation and exploitation in the Sorokdo Island Sanatorium and discrimination against the patients within the sanatorium, which was controlled by the director of the sanatorium. Consequently, the research tends to perceive the problem within the frame of antagonism between the agent of imperialism and the victims of exploitation by the hands of imperialism. Hence, it has limitations in that it has not fully addressed the problem of the people who were not Hansen's disease patients and as such, existed somewhere in between the two extremes in the process of administering medicine under the imperial rule. The purpose of this study is to identify the direction of imperial medicine in the history of Hansen's disease in Japan and to comprehend the characteristics of policy on Hansen's disease developed by Mitsuda Kensuke, who was behind the policy of imperial medicine, and examine the process of imperial medicine reaching out to the people (of Japan and its colonies). To achieve the goal, this study explores how the agent of imperial medicine gain the favor the public, who are not Hansen's disease patients, by means of the mass media. Specifically, this paper examines data in the Japanese language related to Korean patients of Hansen's disease including the mass media data on Hansen's disease in the source book titled The Collection of Data on Hansen's Disease in Joseon under the Colonial Rule(8 volumes) compiled by Takio Eiji, which has not been studied until now. It also reviews the cultural and popular magazines published in Japan and Joseon at that time.

National Hansen's Disease (Leprosy) Program

MedlinePlus

... Date Last Reviewed: May 2018 Hansen's Disease Diagnosis & Management Patient Information English (PDF - 109 KB) Portuguese (PDF - 43 KB) ... in the United States - Diagnosis & Treatment Seminar Comprehensive Management of the Neuropathic Foot ... Links Hansen's Disease (Leprosy) (Centers for Disease ...

The use of solvent extractions and solubility theory to discern hydrocarbon associations in coal, with application to the coal-supercritical CO2 system

USGS Publications Warehouse

Kolak, Jonathan J.; Burruss, Robert A.

2014-01-01

Samples of three high volatile bituminous coals were subjected to parallel sets of extractions involving solvents dichloromethane (DCM), carbon disulfide (CS2), and supercritical carbon dioxide (CO2) (40 °C, 100 bar) to study processes affecting coal–solvent interactions. Recoveries of perdeuterated surrogate compounds, n-hexadecane-d34 and four polycyclic aromatic hydrocarbons (PAHs), added as a spike prior to extraction, provided further insight into these processes. Soxhlet-DCM and Soxhlet-CS2 extractions yielded similar amounts of extractable organic matter (EOM) and distributions of individual hydrocarbons. Supercritical CO2 extractions (40 °C, 100 bar) yielded approximately an order of magnitude less EOM. Hydrocarbon distributions in supercritical CO2 extracts generally mimicked distributions from the other solvent extracts, albeit at lower concentrations. This disparity increased with increasing molecular weight of target hydrocarbons. Five- and six-ring ring PAHs generally were not detected and no asphaltenes were recovered in supercritical CO2 extractions conducted at 40 °C and 100 bar. Supercritical CO2 extraction at elevated temperature (115 °C) enhanced recovery of four-ring and five-ring PAHs, dibenzothiophene (DBT), and perdeuterated PAH surrogate compounds. These results are only partially explained through comparison with previous measurements of hydrocarbon solubility in supercritical CO2. Similarly, an evaluation of extraction results in conjunction with solubility theory (Hildebrand and Hansen solubility parameters) does not fully account for the hydrocarbon distributions observed among the solvent extracts. Coal composition (maceral content) did not appear to affect surrogate recovery during CS2 and DCM extractions but might affect supercritical CO2 extractions, which revealed substantive uptake (partitioning) of PAH surrogates into the coal samples. This uptake was greatest in the sample (IN-1) with the highest vitrinite content. These findings indicate that hydrocarbon solubility does not exert a strong influence on hydrocarbon behavior in the systems studied. Other factors such as coal composition and maceral content, surface processes (physisorption), or other molecular interactions appear to affect the partitioning of hydrocarbons within the coal–supercritical CO2 system. Resolving the extent to which these factors might affect hydrocarbon behavior under different geological settings is important to efforts seeking to model petroleum generation, fractionation and expulsion from coal beds and to delineate potential hydrocarbon fate and transport in geologic CO2 sequestration settings.

Truth and opinion in climate change discourse: the Gore-Hansen disagreement.

PubMed

Russill, Chris

2011-11-01

In this paper, I discuss the "inconvenient truth" strategy of Al Gore. I argue that Gore's notion of truth upholds a conception of science and policy that narrows our understanding of climate change discourse. In one notable exchange, Gore and NASA scientist, James Hansen, disagreed about whether scientific statements based on Hansen's computer simulations were truth or opinion. This exchange is featured in An Inconvenient Truth, yet the disagreement is edited from the film and presented simply as an instance of Hansen speaking "inconvenient truth". In this article, I compare the filmic representation of Hansen's testimony with the congressional record. I place their exchange in a broader historical perspective on climate change disputation in order to discuss the implications of Gore's perspective on truth.

Method development for compositional analysis of low molecular weight poly(vinyl acetate) by matrix-assisted/laser desorption-mass spectrometry and its application to analysis of chewing gum.

PubMed

Tisdale, Evgenia; Wilkins, Charles

2014-04-11

The influence of the sample preparation parameters (the choice of the solvent and of the matrix:analyte ratio) was investigated and optimal conditions were established for MALDI mass spectrometry analysis of the pristine low molecular weight polyvinyl acetate (PVAc). It was demonstrated that comparison of polymer's and solvent's Hansen solubility parameters could be used as a guide when choosing the solvent for MALDI sample preparation. The highest intensity PVAc signals were obtained when ethyl acetate was used as a solvent along with the lowest matrix-analyte ratio (2,5-dihydroxybenzoic acid was used as a matrix in all experiments). The structure of the PVAc was established with high accuracy using the matrix-assisted laser desorption/ionization-Fourier transform mass spectrometry (MALDI-FTMS) analysis. It was demonstrated that PVAc undergoes unimolecular decomposition by losing acetic acid molecules from its backbone under the conditions of FTMS measurements. Number and weight average molecular weights as well as polydispersity indices were determined with both MALDI-TOF and MALDI-FTMS methods. The sample preparation protocol developed was applied to the analysis of a chewing gum and the molecular weight and structure of the polyvinyl acetate present in the sample were established. Thus, it was shown that optimized MALDI mass spectrometry could be used successfully for characterization of polyvinyl acetate in commercially available chewing gum. Copyright © 2014 Elsevier B.V. All rights reserved.

Can Cosmopolitanism Work Religiously? A Response to David T. Hansen

ERIC Educational Resources Information Center

Ghiloni, Aaron J.

2017-01-01

This response to David T. Hansen's 2016 plenary address to the Religious Education Association tests the viability of educational cosmopolitanism for religious education. Using a Deweyan methodology of understanding an idea through its consequences, Hansen's proposal is analyzed using dialogues with interreligious and Islamic pedagogies. The…

Peter Andreas Hansen und die astronomische Gemeinschaft - eine erste Auswertung des Hansen-Nachlasses.

NASA Astrophysics Data System (ADS)

Schwarz, O.; Strumpf, M.

The literary assets of Peter Andreas Hansen are deposited in the Staatsarchiv Hamburg, the Forschungs- und Landesbibliothek Gotha and the Thüringer Staatsarchiv Gotha. They were never systematically investigated. The authors present here some results of a first evaluation. It was possible to reconstruct the historical events with regard to the maintenance of the Astronomische Nachrichten and the Altona observatory in 1854. Hansen was a successful teacher for many young astronomers. His way of stimulating the evolution of astronomy followed Zach's tradition.

Active Surveillance of Hansen's Disease (Leprosy): Importance for Case Finding among Extra-domiciliary Contacts

PubMed Central

Moura, Maria L. N.; Dupnik, Kathryn M.; Sampaio, Gabriel A. A.; Nóbrega, Priscilla F. C.; Jeronimo, Ana K.; do Nascimento-Filho, Jose M.; Miranda Dantas, Roberta L.; Queiroz, Jose W.; Barbosa, James D.; Dias, Gutemberg; Jeronimo, Selma M. B.; Souza, Marcia C. F.; Nobre, Maurício L.

2013-01-01

Hansen's disease (leprosy) remains an important health problem in Brazil, where 34,894 new cases were diagnosed in 2010, corresponding to 15.3% of the world's new cases detected in that year. The purpose of this study was to use home visits as a tool for surveillance of Hansen's disease in a hyperendemic area in Brazil. A total of 258 residences were visited with 719 individuals examined. Of these, 82 individuals had had a previous history of Hansen's disease, 209 were their household contacts and 428 lived in neighboring residences. Fifteen new Hansen's disease cases were confirmed, yielding a detection rate of 2.0% of people examined. There was no difference in the detection rate between household and neighbor contacts (p = 0.615). The two groups had the same background in relation to education (p = 0.510), household income (p = 0.582), and the number of people living in the residence (p = 0.188). Spatial analysis showed clustering of newly diagnosed cases and association with residential coordinates of previously diagnosed multibacillary cases. Active case finding is an important tool for Hansen's disease control in hyperendemic areas, enabling earlier diagnosis, treatment, decrease in disability from Hansen's disease and potentially less spread of Mycobacterium leprae. PMID:23516645

A Return to the Human in Humanism: A Response to Hansen's Humanistic Vision

ERIC Educational Resources Information Center

Lemberger, Matthew E.

2012-01-01

In his extension of the humanistic vision, Hansen (2012) recommends that counseling practitioners and scholars adopt operations that are consistent with his definition of a multiple-perspective philosophy. Alternatively, the author of this article believes that Hansen has reduced the capacity of the human to interpret meaning through quantitative…

Mechanochemical Synthesis of Pharmaceutical Cocrystal Suspensions via Hot Melt Extrusion: Enhancing Cocrystal Yield.

PubMed

Li, Shu; Yu, Tao; Tian, Yiwei; Lagan, Colette; Jones, David S; Andrews, Gavin P

2017-11-22

Pharmaceutical cocrystals have attracted increasing attention over the past decade as an alternative way to modify the physicochemical properties and hence improve the bioavailability of a drug, without sacrificing thermodynamic stability. Our previous work has demonstrated the viability of in-situ formation of ibuprofen/isonicotinamide cocrystal suspensions within a matrix carrier via a single-step hot-melt extrusion (HME) process. The key aim of the current work is to establish optimised processing conditions to improve cocrystal yield within extruded matrices. The solubility of each individual cocrystal component in the matrix carrier was estimated using two different methods, calculation of Hansen solubility parameters, and Flory-Huggins solution theory using melting point depression measurement, respectively. The latter was found to be more relevant to extrusion cocrystallisation because of the ability to predict miscibility across a range of temperatures. The predictions obtained from the F-H phase diagrams were verified using ternary extrusion processing. Temperatures that promote solubilisation of the parent reagents during processing, and precipitation of the newly formed cocrystal were found to be the most suitable in generating high cocrystal yields. The incorporation of intensive mixing/kneading elements to the screw configuration was also shown to significantly improve the cocrystal yield when utilising a matrix platform. This work has shown that intensive mixing in combination with appropriate temperature selection, can significantly improve the cocrystal yield within a stable and low viscosity carrier during HME processing. Most importantly, this work reports, for the very first time in the literature, the use of the F-H phase diagrams to predict the most appropriate HME processing window to drive higher cocrystal yield.

Inverse gas chromatographic determination of solubility parameters of excipients.

PubMed

Adamska, Katarzyna; Voelkel, Adam

2005-11-04

The principle aim of this work was an application of inverse gas chromatography (IGC) for the estimation of solubility parameter for pharmaceutical excipients. The retention data of number of test solutes were used to calculate Flory-Huggins interaction parameter (chi1,2infinity) and than solubility parameter (delta2), corrected solubility parameter (deltaT) and its components (deltad, deltap, deltah) by using different procedures. The influence of different values of test solutes solubility parameter (delta1) over calculated values was estimated. The solubility parameter values obtained for all excipients from the slope, from Guillet and co-workers' procedure are higher than that obtained from components according Voelkel and Janas procedure. It was found that solubility parameter's value of the test solutes influences, but not significantly, values of solubility parameter of excipients.

Isotropy of the early universe from CMB anisotropies

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

Donoghue, Evan P.; University of Notre Dame, Notre Dame, Indiana 46556; Donoghue, John F.

The acoustic peak in the cosmic microwave background power spectrum is sensitive to causal processes and cosmological parameters in the early universe up to the time of last scattering. We provide limits on correlated spatial variations of the peak height and peak position and interpret these as constraints on the spatial variation of the cosmological parameters (baryon density, cold dark matter density, and cosmological constant as well as the amplitude and tilt of the original fluctuations). We utilize recent work of Hansen, Banday, and Gorski who have studied the spatial isotropy of the power spectrum as measured by WMAP bymore » performing the power spectrum analysis on smaller patches of the sky. We find that there is no statistically significant correlated asymmetry of the peak. Hansen, Banday, and Gorski have also provided preliminary indications of a preferred direction in the lower angular momentum range (l{approx}2-40) and we show how possible explanations of this asymmetry are severely constrained by the data on the acoustic peak. Finally we show a possible non-Gaussian feature in the data, associated with a difference in the northern and southern galactic hemispheres.« less

The Value of Social Constructionism for the Counseling Profession: A Reply to Hansen

ERIC Educational Resources Information Center

Rudes, James; Guterman, Jeffrey T.

2007-01-01

The authors reply to J. T. Hansen's (2005) call for the profession to revalue the inner subjective experiences (ISE) of clients. Hansen argued that social constructionism has influenced the decline of the counseling profession by obscuring its unique focus on ISE. The authors maintain that social constructionism is a useful framework for…

Extending the Dialogue about Science and Humanities in Counseling: A Reply to Hansen

ERIC Educational Resources Information Center

Martin, Clayton V.; Guterman, Jeffrey T.; Kopp, David M.

2012-01-01

This is a reply to Hansen's (2012b) rejoinder to the authors (Guterman, Martin, & Kopp, 2012), which is a response to Hansen's (2012a) keystone article about the relationship between humanities and science in counseling. In this reply, the authors provide remaining clarifications, points of disagreement, and suggestions for future directions in…

Towards uniformly dispersed battery electrode composite materials: Characteristics and performance

DOE PAGES

Yo Han Kwon; Takeuchi, Esther S.; Huie, Matthew M.; ...

2016-01-14

Battery electrodes are complex mesoscale systems comprised of electroactive components, conductive additives, and binders. In this report, methods for processing electrodes with dispersion of the components are described. To investigate the degree of material dispersion, a spin-coating technique was adopted to provide a thin, uniform layer that enabled observation of the morphology. Distinct differences in the distribution profile of the electrode components arising from individual materials physical affinities were readily identified. Hansen solubility parameter (HSP) analysis revealed pertinent surface interactions associated with materials dispersivity. Further studies demonstrated that HSPs can provide an effective strategy to identify surface modification approaches formore » improved dispersions of battery electrode materials. Specifically, introduction of surfactantlike functionality such as oleic acid (OA) capping and P3HT-conjugated polymer wrapping on the surface of nanomaterials significantly enhanced material dispersity over the composite electrode. The approach to the surface treatment on the basis of HSP study can facilitate design of composite electrodes with uniformly dispersed morphology and may contribute to enhancing their electrical and electrochemical behaviors. The conductivity of the composites and their electrochemical performance was also characterized. In conclusion, the study illustrates the importance of considering electronic conductivity, electron transfer, and ion transport in the design of environments incorporating active nanomaterials.« less

High throughput atmospheric pressure plasma-induced graft polymerization for identifying protein-resistant surfaces.

PubMed

Gu, Minghao; Kilduff, James E; Belfort, Georges

2012-02-01

Three critical aspects of searching for and understanding how to find highly resistant surfaces to protein adhesion are addressed here with specific application to synthetic membrane filtration. They include the (i) discovery of a series of previously unreported monomers from a large library of monomers with high protein resistance and subsequent low fouling characteristics for membrane ultrafiltration of protein-containing fluids, (ii) development of a new approach to investigate protein-resistant mechanisms from structure-property relationships, and (iii) adaptation of a new surface modification method, called atmospheric pressure plasma-induced graft polymerization (APP), together with a high throughput platform (HTP), for low cost vacuum-free synthesis of anti-fouling membranes. Several new high-performing chemistries comprising two polyethylene glycol (PEG), two amines and one zwitterionic monomers were identified from a library (44 commercial monomers) of five different classes of monomers as strong protein-resistant monomers. Combining our analysis here, using the Hansen solubility parameters (HSP) approach, and data from the literature, we conclude that strong interactions with water (hydrogen bonding) and surface flexibility are necessary for producing the highest protein resistance. Superior protein-resistant surfaces and subsequent anti-fouling performance was obtained with the HTP-APP as compared with our earlier HTP-photo graft-induced polymerization (PGP). Copyright © 2011 Elsevier Ltd. All rights reserved.

Towards uniformly dispersed battery electrode composite materials: Characteristics and performance

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

Yo Han Kwon; Takeuchi, Esther S.; Huie, Matthew M.

Battery electrodes are complex mesoscale systems comprised of electroactive components, conductive additives, and binders. In this report, methods for processing electrodes with dispersion of the components are described. To investigate the degree of material dispersion, a spin-coating technique was adopted to provide a thin, uniform layer that enabled observation of the morphology. Distinct differences in the distribution profile of the electrode components arising from individual materials physical affinities were readily identified. Hansen solubility parameter (HSP) analysis revealed pertinent surface interactions associated with materials dispersivity. Further studies demonstrated that HSPs can provide an effective strategy to identify surface modification approaches formore » improved dispersions of battery electrode materials. Specifically, introduction of surfactantlike functionality such as oleic acid (OA) capping and P3HT-conjugated polymer wrapping on the surface of nanomaterials significantly enhanced material dispersity over the composite electrode. The approach to the surface treatment on the basis of HSP study can facilitate design of composite electrodes with uniformly dispersed morphology and may contribute to enhancing their electrical and electrochemical behaviors. The conductivity of the composites and their electrochemical performance was also characterized. In conclusion, the study illustrates the importance of considering electronic conductivity, electron transfer, and ion transport in the design of environments incorporating active nanomaterials.« less

Tar Management and Recycling in Biomass Gasification and Syngas Purification

NASA Astrophysics Data System (ADS)

McCaffrey, Zach

Removal of tars is critical to the design and operation of biomass gasification systems as most syngas utilization processing equipment (e.g. internal combustion engines, gas turbines, fuel cells, and liquid fuel synthesis reactors) have a low tolerance for tar. Capturing and disposal of tar is expensive due to equipment costs, high hazardous waste disposal costs where direct uses cannot be found, and system energy losses incurred. Water scrubbing is an existing technique commonly used in gasification plants to remove contaminants and tar; however using water as the absorbent is non-ideal as tar compounds have low or no water solubility. Hydrophobic solvents can improve scrubber performance and this study evaluated tar solubility in selected solvents using slip-streams of untreated syngas from a laboratory fluidized bed reactor operated on almond composite feedstock using both air and steam gasification. Tar solubility was compared with Hansen's solubility theory to examine the extent to which the tar removal can be predicted. As collection of tar without utilization leads to a hazardous waste problem, the study investigated the effects of recycling tars back into the gasifier for destruction. Prior to experiments conducted on tar capture and recycle, characterizations of the air and steam gasification of the almond composite mix were made. This work aims to provide a better understanding of tar collection and solvent selection for wet scrubbers, and to provide information for designing improved tar management systems for biomass gasification.

Memories and history of Hansen's disease in Brazil told by witnesses (1960-2000).

PubMed

Rosa Maciel, Laurinda; Oliveira, Maria Leide Wand-del-Rey; Gallo, Maria Eugênia N; Damasco, Mariana Santos

2003-01-01

This report is a preliminary result of a survey on memories and history of Hansen's disease, or 'hanseniasis', prepared by the Fundação Oswaldo Cruz (Fiocruz) and the Universidade Federal do Rio de Janeiro (UFRJ) using statements from those who have been afflicted by the disease or those that have fought against it. It outlines the methodology used by the authors and gives a succinct history of Hansen's disease in Brazil, together wish information on the stage of the survey with extracts from our archives of statements. The founding and the role of Movement for the Reintegration of People Afflicted by Hansen's Disease (Morhan) are explained in the testimony of Thomas Frist, a social scientist who worked in Brazil in the 1970s and 1980s, when the country's old colonies were being restructured, and Cristiano Torres, a former patient who spent time in prevention centers and leproseries in Pará state and who is now active in proposing new policy for the control of Hansen's disease.

9.73% Efficiency Nonfullerene All Organic Small Molecule Solar Cells with Absorption-Complementary Donor and Acceptor.

PubMed

Bin, Haijun; Yang, Yankang; Zhang, Zhi-Guo; Ye, Long; Ghasemi, Masoud; Chen, Shanshan; Zhang, Yindong; Zhang, Chunfeng; Sun, Chenkai; Xue, Lingwei; Yang, Changduk; Ade, Harald; Li, Yongfang

2017-03-29

In the last two years, polymer solar cells (PSCs) developed quickly with n-type organic semiconductor (n-OSs) as acceptor. In contrast, the research progress of nonfullerene organic solar cells (OSCs) with organic small molecule as donor and the n-OS as acceptor lags behind. Here, we synthesized a D-A structured medium bandgap organic small molecule H11 with bithienyl-benzodithiophene (BDTT) as central donor unit and fluorobenzotriazole as acceptor unit, and achieved a power conversion efficiency (PCE) of 9.73% for the all organic small molecules OSCs with H11 as donor and a low bandgap n-OS IDIC as acceptor. A control molecule H12 without thiophene conjugated side chains on the BDT unit was also synthesized for investigating the effect of the thiophene conjugated side chains on the photovoltaic performance of the p-type organic semiconductors (p-OSs). Compared with H12, the 2D-conjugated H11 with thiophene conjugated side chains shows intense absorption, low-lying HOMO energy level, higher hole mobility and ordered bimodal crystallite packing in the blend films. Moreover, a larger interaction parameter (χ) was observed in the H11 blends calculated from Hansen solubility parameters and differential scanning calorimetry measurements. These special features combined with the complementary absorption of H11 donor and IDIC acceptor resulted in the best PCE of 9.73% for nonfullerene all small molecule OSCs up to date. Our results indicate that fluorobenzotriazole based 2D conjugated p-OSs are promising medium bandgap donors in the nonfullerene OSCs.

The Solubility Parameters of Ionic Liquids

PubMed Central

Marciniak, Andrzej

2010-01-01

The Hildebrand’s solubility parameters have been calculated for 18 ionic liquids from the inverse gas chromatography measurements of the activity coefficients at infinite dilution. Retention data were used for the calculation. The solubility parameters are helpful for the prediction of the solubility in the binary solvent mixtures. From the solubility parameters, the standard enthalpies of vaporization of ionic liquids were estimated. PMID:20559495

Correlation of Paleocene Harmon and Hansen lignite beds, Adams, Billings, Bowman, Golden Valley, Hettinger, and Slope Counties, Williston Basin, North Dakota

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

Keighin, C.W.; Flores, R.M.; Ochs, A.

In southwestern North Dakota, minable lignite beds in the Paleocene Fort Union Formation include the Harmon and Hansen beds in the Bowman-Gascoyne area. Data from more than 700 drill holes penetrating these beds was used to construct stratigraphic cross sections. The Harmon and Hansen beds are the thickest and most laterally persistent lignites found under < 150 ft of overburden. The Harmon coal bed is as much as 34 ft thick, and is often split by claystone interbeds of variable thickness. The Hansen coal bed typically occurs 10--100 ft below the Harmon coal bed; it rarely attains a thickness ofmore » 15 ft, and averages 4 ft in thickness.« less

[Early diagnosis of Hansen disease: study of the health services in Recife (Pernambuco), Brazil].

PubMed

Feliciano, K V; Kovacs, M H; Alzate, A

1998-07-01

This paper presents the results of a descriptive study carried out in the city of Recife, state of Pernambuco, Brazil, between March and September 1994. The study aimed at health services available for performing early diagnosis of Hansen's disease with emphasis on accessibility and quality of the services provided. The sample consisted of 32 health clinics visited for diagnostic purposes by 183 patients with Hansen's disease. Information on organizational infrastructures was collected by means of interviews with health clinic managers. Information regarding routine procedures in the 32 clinics was collected by observation, with special attention given to archival and inspection activities. A total of 1,998 patients were interviewed to determine accessibility of services. Time spent in consultation with the physician was determined for 1,000 patients who were seen by 123 physicians at the clinics during the interviews. To explore physicians' attitude and knowledge regarding Hansen's disease, 133 were randomly selected from a list of names. The following factors were identified as hindering early diagnosis of Hansen's disease: the large number of people seeking service who could not be seen by a physician on the same day; the long time elapsed between appointment scheduling and the actual visit (for those not seen on the same day); the long wait for the consultation; the brevity of the consultation; the low availability of trained personnel; the low proportion of physicians who examined all body surfaces; difficulties in the clinical recognition of the disease; and physicians not prepared to make a differential diagnosis. These obstacles can precipitate the physical deterioration of Hansen's disease patients and stimulate the persistence of transmissibility; therefore, they need to be overcome if Hansen's disease is to be eliminated.

The production of social discourse on Hansen' disease and health education materials in Brazil: a skin patch as something harmless or a serious disease?

PubMed

Santos, Adriana Kelly; Ribeiro, Ana Paula Goulart; Monteiro, Simone

2012-03-01

Hansen's disease is endemic in Brazil and government control programmes promote publicity campaigns to increase the detection of new cases through the production and distribution of educative material. This study analyses a set of 276 educational materials produced by governmental and non-governmental organisations that work to control Hansen's disease in Brazil. It describes the content of the materials and the way the issues were approached. It is a qualitative study that adopts the theoretical and methodological framework of the semiology of social discourse. Analysis reveals that the relations between the enunciator and recipient of the materials are asymmetrical as a result of the technical and educational language employed. Biomedical information forms the basis for social representations an practices of Hansen's disease, as opposed to historical collective knowledge of 'leprosy'. The prioritised topics are: signs and symptoms of the disease, treatment stigma, cure and surveillance. The institutionalisation of public education on Hansen's disease in Brazil was not limited simply to the change of terminology from 'leprosy' to 'Hansen's disease,' but was shaped also by new educational practices. It is recommended that the evaluation and production of new materials be incorporated into the set of activities already carried out in health centres so as to expand the discussion on content, language and the best way to address the disease in the materials.

The Hildebrand solubility parameters of ionic liquids-part 2.

PubMed

Marciniak, Andrzej

2011-01-01

The Hildebrand solubility parameters have been calculated for eight ionic liquids. Retention data from the inverse gas chromatography measurements of the activity coefficients at infinite dilution were used for the calculation. From the solubility parameters, the enthalpies of vaporization of ionic liquids were estimated. Results are compared with solubility parameters estimated by different methods.

[The compulsory isolation of Hansen's disease patients: memories of the elderly].

PubMed

de Castro, Selma Munhoz Sanches; Watanabe, Helena Akemi Wada

2009-01-01

From 1924 to 1962, Brazil used compulsory internment of Hansen's disease patients as one of the ways of controlling the disease in the community. After this policy ended, many patients continued to live in these units. The former Asilo Pirapitingui, now the Hospital Dr. Francisco Ribeiro Arantes, is the only old-style asylum for the socially determined internment of those suffering from Hansen's disease. Through recorded and transcribed interviews of eight of those remaining, we sought to learn their history and the meaning of this isolation in their lives. The thematic analysis of the discourse enabled identification of the following analysis categories: Hansen's disease; internment day-to-day life; the institution; current health conditions; and staying in the institution after the end of compulsory internment.

The Influence of Drug Physical State on the Dissolution Enhancement of Solid Dispersions Prepared Via Hot-Melt Extrusion: A Case Study Using Olanzapine

PubMed Central

Pina, Maria Fátima; Zhao, Min; Pinto, João F; Sousa, João J; Craig, Duncan Q M

2014-01-01

In this study, we examine the relationship between the physical structure and dissolution behavior of olanzapine (OLZ) prepared via hot-melt extrusion in three polymers [polyvinylpyrrolidone (PVP) K30, polyvinylpyrrolidone-co-vinyl acetate (PVPVA) 6:4, and Soluplus® (SLP)]. In particular, we examine whether full amorphicity is necessary to achieve a favorable dissolution profile. Drug–polymer miscibility was estimated using melting point depression and Hansen solubility parameters. Solid dispersions were characterized using differential scanning calorimetry, X-ray powder diffraction, and scanning electron microscopy. All the polymers were found to be miscible with OLZ in a decreasing order of PVP>PVPVA>SLP. At a lower extrusion temperature (160°C), PVP generated fully amorphous dispersions with OLZ, whereas the formulations with PVPVA and SLP contained 14%–16% crystalline OLZ. Increasing the extrusion temperature to 180°C allowed the preparation of fully amorphous systems with PVPVA and SLP. Despite these differences, the dissolution rates of these preparations were comparable, with PVP showing a lower release rate despite being fully amorphous. These findings suggested that, at least in the particular case of OLZ, the absence of crystalline material may not be critical to the dissolution performance. We suggest alternative key factors determining dissolution, particularly the dissolution behavior of the polymers themselves. PMID:24765654

Selective extraction of high-value phenolic compounds from distillation wastewater of basil (Ocimum basilicum L.) by pressurized liquid extraction.

PubMed

Pagano, Imma; Sánchez-Camargo, Andrea Del Pilar; Mendiola, Jose Antonio; Campone, Luca; Cifuentes, Alejandro; Rastrelli, Luca; Ibañez, Elena

2018-01-31

During the essential oil steam distillation from aromatic herbs, huge amounts of distillation wastewaters (DWWs) are generated. These by-products represent an exceptionally rich source of phenolic compounds such as rosmarinic acid (RA) and caffeic acid (CA). Herein, the alternative use of dried basil DWWs (dDWWs) to perform a selective extraction of RA and CA by pressurized liquid extraction (PLE) employing bio-based solvent was studied. To select the most suitable solvent for PLE, the theoretical modelling of Hansen solubility parameters (HSP) was carried out. This approach allows reducing the list of candidate to two solvents: ethanol and ethyl lactate. Due to the composition of the sample, mixtures of water with those solvents were also tested. An enriched PLE extract in RA (23.90 ± 2.06 mg/g extract) with an extraction efficiency of 75.89 ± 16.03% employing a water-ethanol mixture 25:75 (% v/v) at 50°C was obtained. In the case of CA, a PLE extract with 2.42 ± 0.04 mg/g extract, having an extraction efficiency of 13.86 ± 4.96% using ethanol absolute at 50°C was achieved. DWWs are proposed as new promising sources of natural additives and/or functional ingredients for cosmetic, nutraceutical, and food applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effect of the solvent on the size of clay nanoparticles in solution as determined using an ultraviolet-visible (UV-Vis) spectroscopy methodology.

PubMed

Alin, Jonas; Rubino, Maria; Auras, Rafael

2015-06-01

Ultraviolet-visible (UV-Vis) spectroscopy methodology was developed and utilized for the in situ nanoscale measurement of the size of mineral clay agglomerates in various liquid suspensions. The clays studied were organomodified and unmodified montmorillonite clays (I.44p, Cloisite 93a, and PGN). The methodology was compared and validated against dynamic light scattering (DLS) analysis. The method was able to measure clay agglomerates in solvents in situations where DLS analysis was unsuccessful due to the shapes, polydispersity, and high aspect ratios of the clay particles and the complexity of the aggregates, or dispersion medium. The measured clay agglomerates in suspension were found to be in the nanometer range in the more compatible solvents, and their sizes correlated with the Hansen solubility parameter space distance between the clay modifiers and the solvents. Mass detection limits for size determination were in the range from 1 to 9 mg/L. The methodology thus provides simple, rapid, and inexpensive characterization of clays or particles in the nano- or microsize range in low concentrations in various liquid media, including complex mixtures or highly viscous fluids that are difficult to analyze with DLS. In addition, by combining UV-VIS spectroscopy with DLS it was possible to discern flocculation behavior in liquids, which otherwise could result in false size measurements by DLS alone.

The Hildebrand Solubility Parameters of Ionic Liquids—Part 2

PubMed Central

Marciniak, Andrzej

2011-01-01

The Hildebrand solubility parameters have been calculated for eight ionic liquids. Retention data from the inverse gas chromatography measurements of the activity coefficients at infinite dilution were used for the calculation. From the solubility parameters, the enthalpies of vaporization of ionic liquids were estimated. Results are compared with solubility parameters estimated by different methods. PMID:21747694

Treatment of leprosy/Hansen's disease in the early 21st century.

PubMed

Worobec, Sophie M

2009-01-01

Leprosy, or Hansen's disease (HD), is caused by Mycobacterium leprae, a slowly dividing mycobacterium that has evolved to be an intracellular parasite, causing skin lesions and nerve damage. Less than 5% of people exposed to M. leprae develop clinical disease. Host cell-mediated resistance determines whether an individual will develop paucibacillary or multibacillary disease. Hansen's disease is a worldwide disease with about 150 new cases reported annually in the United States. Effective anti-mycobacterial treatments are available, and many patients experience severe reversal and erythema nodosum leprosum reactions that also require treatment. Leprosy has been the target of a World Health Organization multiple drug therapy campaign to eliminate it as a national public health problem in member countries, but endemic regions persist. In the United States, the National Hansen's Disease Program has primary responsibility for medical care, research, and information.

Leprosy (Hansen's Disease)

MedlinePlus

... See all Leprosy (Hansen's Disease) related NIAID Now posts Basic Research NIAID-funded investigators are developing the armadillo as a research animal model for human leprosy and developing improved skin test antigens to detect leprosy. Read more about leprosy ...

The solubility parameter for biomedical polymers-Application of inverse gas chromatography.

PubMed

Adamska, K; Voelkel, A; Berlińska, A

2016-08-05

The solubility parameter seems to be a useful tool for thermodynamic characterisation of different materials. The solubility parameter concept can be used to predict sufficient miscibility or solubility between a solvent and a polymer, as well as components of co-polymer matrix in composite biomaterials. The values of solubility parameter were determined for polycaprolactone (PCL), polylactic acid (PLA) and polyethylene glycol (PEG) by using different procedures and experimental data, collected by means of inverse gas chromatography. Copyright © 2016 Elsevier B.V. All rights reserved.

75 FR 49516 - Lewis and Clark National Wildlife Refuge and the Julia Butler Hansen Refuge for the Columbian...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-13

... that dredge-spoil islands provide benefits for wildlife. Julia Butler Hansen Refuge Alternative 1 Under... safety purposes, studying potential wilderness lands, developing a bicycling and hiking trail, installing...

DROMO Propagator Revisited

NASA Astrophysics Data System (ADS)

Urrutxua, H.; Sanjurjo-Rivo, M.; Peláez, J.

2013-12-01

In year 2000 a house-made orbital propagator was developed by the SDGUPM (former Grupo de Dinámica de Tethers) based in a set of redundant variables including Euler parameters. This propagator was called DROMO. and it was mainly used in numerical simulations of electrodynamic tethers. It was presented for the first time in the international meeting V Jornadas de Trabajo en Mecánica Celeste, held in Albarracín, Spain, in 2002 (see reference 1). The special perturbation method associated with DROMO can be consulted in the paper.2 In year 1975, Andre Deprit in reference 3 proposes a propagation scheme very similar to the one in which DROMO is based, by using the ideal frame concept of Hansen. The different approaches used in references 3 and 2 gave rise to a small controversy. In this paper we carried out a different deduction of the DROMO propagator, underlining its close relation with the Hansen ideal frame concept, and also the similarities and the differences with the theory carried out by Deprit in 3. Simultaneously we introduce some improvements in the formulation that leads to a more synthetic propagator.

78 FR 40738 - Proposed CERCLA Administrative Cost Recovery Settlement; Double H Pesticide Burial Site

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-08

... are Double H, L.P.; James T. Hansen; Linda L. Hansen; George W. Higgins; and Edith M. Higgins. The... their original terms. Dated: June 27, 2013. Chris D. Field, Manager, Emergency Management Program, U.S...

Arctic Technology Evaluation 2014 Oil-in-Ice Demonstration Report

DTIC Science & Technology

2015-03-01

Spills in Ice”, 2014 International Oil Spill Conference, Savannah, GA, May, 2014. Hansen, Kurt A., Scot T. Trip, Rich L. Hansen (2014) “Evaluating...Operations”, Woods Hole Oceanographic Institution (WHOI) report to BSEE, 2013. Arctic Technology Evaluation 2014 Oil-in-Ice Demonstration Report 40

Validity of Hansen-Roach cross sections in low-enriched uranium systems

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

Busch, R.D.; O'Dell, R.D.

Within the nuclear criticality safety community, the Hansen-Roach 16 group cross section set has been the standard'' for use in k{sub eff} calculations over the past 30 years. Yet even with its widespread acceptance, there are still questions about its validity and adequacy, about the proper procedure for calculating the potential scattering cross section, {sigma}{sub p}, for uranium and plutonium, and about the concept of resonance self shielding and its impact on cross sections. This paper attempts to address these questions. It provides a brief background on the Hansen-Roach cross sections. Next is presented a review of resonances in crossmore » sections, self shielding of these resonances, and the use of {sigma}{sub p} to characterize resonance self shielding. Three prescriptions for calculating {sigma}{sub p} are given. Finally, results of several calculations of k{sub eff} on low-enriched uranium systems are provided to confirm the validity of the Hansen-Roach cross sections when applied to such systems.« less

Arthur Hansen: engineering education to fit the times

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

Not Available

Dr Hansen, president of Purdue University, reports that students are eager to try solving today's complex energy and environmental problems. He expressed his views on university students' aims during the 1960s and the resultant unrest, but believes that students of today are more mature and are working harder for tangible results. Part of the approach at Purdue, he says, is to provide students with an education that will help them survive social and technological changes. The main facets of the EPRI program are reviewed, pointing out the main reasons for its existence. ''Every student should have a basic knowledge ofmore » technology,'' Dr. Hansen says. (MCW)« less

Rejoinder to Hansen

ERIC Educational Resources Information Center

Suthakaran, V.

2012-01-01

Hansen (2012b) reiterates his view that the humanities should form the ideological foundation of the counseling profession by challenging the validity of the central premises for the author's argument that the humanities and science should have equal ideological standing. The author attempts to explain the reasons for their conflicting ideas on…

Anion exchange membranes composed of a poly(2,6-dimethyl-1,4-phenylene oxide) random copolymer functionalized with a bulky phosphonium cation

DOE PAGES

Liu, Ye; Zhang, Bingzi; Kinsinger, Corey L.; ...

2016-01-22

A random copolymer, tris(2,4,6-trimethoxyphenyl) phosphonium functionalized poly(2,6-dimethyl-1,4-phenylene oxide) (PPO-TPQP) was cast from three different solvents: dimethyl sulfoxide (DMSO), ethyl lactate, or a 41:59 vol% mixture of DMSO and ethyl lactate. Solvents were selected via analysis of the Hansen solubility parameters to vary the phase separation of the polymer in the films. An optimized mixture of DMSO and ethyl lactate chosen for film fabrication and this film was contrasted with films cast from the neat constituent solvents. Atomic force microscopy identified domains from nanometer to tens of nanometer sizes, while the light microscopy showed features on the order of micron. SAXSmore » revealed a cation scattering peak with a d-spacing from 7 to 15 Å. Trends in conductivity and water diffusion for the membranes vary depending on the solvent from which they are cast. The mixed solvent cast membrane shows a linear Arrhenius behavior indicating fully dissociated cationic/anionic groups, and has the highest bromide conductivity of 3 mS/cm at 95% RH, 90 °C. The ethyl lactate cast membrane shows a linear Arrhenius relation in conductivity, but a Vogel-Tamman-Fulcher behavior in its water self-diffusion. While water increases bromide dissociation, water and bromide transport in these films seems to be decoupled. Lastly, this is particularly true for the film cast from ethyl lactate.« less

Anion exchange membranes composed of a poly(2,6-dimethyl-1,4-phenylene oxide) random copolymer functionalized with a bulky phosphonium cation

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

Liu, Ye; Zhang, Bingzi; Kinsinger, Corey L.

A random copolymer, tris(2,4,6-trimethoxyphenyl) phosphonium functionalized poly(2,6-dimethyl-1,4-phenylene oxide) (PPO-TPQP) was cast from three different solvents: dimethyl sulfoxide (DMSO), ethyl lactate, or a 41:59 vol% mixture of DMSO and ethyl lactate. Solvents were selected via analysis of the Hansen solubility parameters to vary the phase separation of the polymer in the films. An optimized mixture of DMSO and ethyl lactate chosen for film fabrication and this film was contrasted with films cast from the neat constituent solvents. Atomic force microscopy identified domains from nanometer to tens of nanometer sizes, while the light microscopy showed features on the order of micron. SAXSmore » revealed a cation scattering peak with a d-spacing from 7 to 15 A. Trends in conductivity and water diffusion for the membranes vary depending on the solvent from which they are cast. The mixed solvent cast membrane shows a linear Arrhenius behavior indicating fully dissociated cationic/anionic groups, and has the highest bromide conductivity of 3 mS/cm at 95% RH, 90 degrees C. The ethyl lactate cast membrane shows a linear Arrhenius relation in conductivity, but a Vogel-Tamman-Fulcher behavior in its water self-diffusion. While water increases bromide dissociation, water and bromide transport in these films seems to be decoupled. This is particularly true for the film cast from ethyl lactate.« less

Anion exchange membranes composed of a poly(2,6-dimethyl-1,4-phenylene oxide) random copolymer functionalized with a bulky phosphonium cation

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

Liu, Ye; Zhang, Bingzi; Kinsinger, Corey L.

A random copolymer, tris(2,4,6-trimethoxyphenyl) phosphonium functionalized poly(2,6-dimethyl-1,4-phenylene oxide) (PPO-TPQP) was cast from three different solvents: dimethyl sulfoxide (DMSO), ethyl lactate, or a 41:59 vol% mixture of DMSO and ethyl lactate. Solvents were selected via analysis of the Hansen solubility parameters to vary the phase separation of the polymer in the films. An optimized mixture of DMSO and ethyl lactate chosen for film fabrication and this film was contrasted with films cast from the neat constituent solvents. Atomic force microscopy identified domains from nanometer to tens of nanometer sizes, while the light microscopy showed features on the order of micron. SAXSmore » revealed a cation scattering peak with a d-spacing from 7 to 15 Å. Trends in conductivity and water diffusion for the membranes vary depending on the solvent from which they are cast. The mixed solvent cast membrane shows a linear Arrhenius behavior indicating fully dissociated cationic/anionic groups, and has the highest bromide conductivity of 3 mS/cm at 95% RH, 90 °C. The ethyl lactate cast membrane shows a linear Arrhenius relation in conductivity, but a Vogel-Tamman-Fulcher behavior in its water self-diffusion. While water increases bromide dissociation, water and bromide transport in these films seems to be decoupled. Lastly, this is particularly true for the film cast from ethyl lactate.« less

42 CFR 32.86 - Admissions to Service facilities.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Admissions to Service facilities. 32.86 Section 32.86 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES MEDICAL CARE AND... Hansen's Disease § 32.86 Admissions to Service facilities. Any person with Hansen's disease who presents...

Optoacoustic Spectroscopy to Detect Hydrazine Fuels.

DTIC Science & Technology

1981-07-01

signals in noise. Proc IEEE 58:610 (1970). 303. Rosen, H., A. D. Hansen, L. Gundel, and T. Novakov . Photoacoustic investigation of urban aerosol...Appl Phys 40:5404 (1969). 383. Yasa, Z., N. M. Amer, H. Rosen, A. D. Hansen, and T. Novakov . Photoacous- tic investigation of urban aerosol particles

Music Education as a Mirror to Humane Education

ERIC Educational Resources Information Center

Hansen, David T.

2017-01-01

Music and philosophy travel together through time in human culture, and in this article, David Hansen responds to Randall Allsup's recent book, "Remixing the Classroom: Toward an Open Philosophy of Music Education." Hansen says that a singular feature of Randall's new book is how marvelously he demonstrates the organic union between…

An Analysis of Alterity in Teachers' Inclusive Pedagogical Practices

ERIC Educational Resources Information Center

Sagner-Tapia, Johanna

2018-01-01

This investigation contributes to understanding how teachers reflect on the other with a disability and on their own practices. Literature suggests that inclusion takes place when barriers are removed, allowing participation. However, scholars agree that teachers still struggle with pedagogical practices in inclusive classrooms. Hansen (Hansen,…

Comparison of Hansen--Roach and ENDF/B-IV cross sections for $sup 233$U criticality calculations

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

McNeany, S. R.; Jenkins, J. D.

A comparison is made between criticality calculations performed using ENDF/B-IV cross sections and the 16-group Hansen-- Roach library at ORNL. The area investigated is homogeneous systems of highly enriched $sup 233$U in simple geometries. Calculations are compared with experimental data for a wide range of H/$sup 233$U ratios. Results show that calculations of k/sub eff/ made with the Hansen--Roach cross sections agree within 1.5 percent for the experiments considered. Results using ENDF/B-IV cross sections were in good agreement for well-thermalized systems, but discrepancies up to 7 percent in k/sub eff/ were observed in fast and epithermal systems. (auth)

Reaffirming the Role of Science and Diversity in Counseling: A Reply to Hansen

ERIC Educational Resources Information Center

Brady-Amoon, Peggy

2012-01-01

Overall, Hansen (2012a) and the author (Brady-Amoon, 2012) share a humanistic vision for the future of counseling. In this continued dialogue, the author argues that a broad-based philosophy of science that encompasses renewed respect for diversity remains essential for the future of the profession.

Humanities and Science: A Necessary Unity for the Counseling Profession

ERIC Educational Resources Information Center

Guterman, Jeffrey T.; Martin, Clayton V.; Kopp, David M.

2012-01-01

This article is a reply to Hansen's (2012) call for the counseling profession to embrace a purely humanistic ideology for counseling. The authors suggest the relationship between humanities and science set forth by Hansen does not emphasize the both-and aspects of these ideologies. An integrative framework is considered for counseling.

A Reply to Hansen's Cultural Humanism

ERIC Educational Resources Information Center

Lemberger, Matthew E.

2012-01-01

Hansen (2012b) responds to the author's (Lemberger, 2012) critique of his humanistic vision by dividing their arguments as either individual or cultural in design. In this reply, the author contends that the individual cannot be extracted from her or his culture and, therefore, what is sufficient for a humanistic counseling culture must also be…

Convergence of Personality and Interests: Meta-Analysis of the Multidimensional Personality Questionnaire and the Strong Interest Inventory

ERIC Educational Resources Information Center

Staggs, Gena D.; Larson, Lisa M.; Borgen, Fred H.

2007-01-01

Using meta-analysis, we revised Ackerman and Heggestad's (1997) identification of four trait complexes that propose personality and interest (P-I) linkages. Studies that had reported correlations between general and specific measures of vocational interests (Strong Interest Inventory [Strong; Hansen & Campbell, 1985; Harmon, Hansen, Borgen,…

Among School Teachers: Bearing Witness as an Orientation in Educational Inquiry

ERIC Educational Resources Information Center

Hansen, David T.

2017-01-01

In this writing, David Hansen illuminates the aesthetic, moral, and epistemic meaning of bearing witness to teaching and teachers by drawing upon a recently completed field-based endeavor that included extensive school visits. Hansen shows how bearing witness can bring the inquirer close to the truth of teaching. However, the witness must…

38 CFR 3.552 - Adjustment of allowance for aid and attendance.

Code of Federal Regulations, 2011 CFR

2011-07-01

... extremities together with loss of anal and bladder sphincter control, or Hansen's disease, except where... the provisions of § 3.551 (except where the disabling condition is Hansen's disease) . (3) Additional... authorized by this section. The rates specified will also be increased by amounts authorized under 38 U.S.C...

38 CFR 3.552 - Adjustment of allowance for aid and attendance.

Code of Federal Regulations, 2012 CFR

2012-07-01

... extremities together with loss of anal and bladder sphincter control, or Hansen's disease, except where... the provisions of § 3.551 (except where the disabling condition is Hansen's disease) . (3) Additional... authorized by this section. The rates specified will also be increased by amounts authorized under 38 U.S.C...

38 CFR 3.552 - Adjustment of allowance for aid and attendance.

Code of Federal Regulations, 2014 CFR

2014-07-01

... extremities together with loss of anal and bladder sphincter control, or Hansen's disease, except where... the provisions of § 3.551 (except where the disabling condition is Hansen's disease) . (3) Additional... authorized by this section. The rates specified will also be increased by amounts authorized under 38 U.S.C...

38 CFR 3.552 - Adjustment of allowance for aid and attendance.

Code of Federal Regulations, 2013 CFR

2013-07-01

... extremities together with loss of anal and bladder sphincter control, or Hansen's disease, except where... the provisions of § 3.551 (except where the disabling condition is Hansen's disease) . (3) Additional... authorized by this section. The rates specified will also be increased by amounts authorized under 38 U.S.C...

Surviving the "School of Slavery": Acculturation in Sharon Draper's "Copper Sun" and Joyce Hansen's "The Captive"

ERIC Educational Resources Information Center

Chandler, Karen Michele

2016-01-01

Although children's literature has long alluded to cultural connections between Africans and African Americans, very few texts establish clear lines of influence between particular African ethnic groups and African American characters and communities. Joyce Hansen's "The Captive" (1994) and Sharon Draper's "Copper Sun" (2006)…

Birth of a Canon: The Historiography of Early Republican Educational Thought. Historiographical Essay.

ERIC Educational Resources Information Center

Moroney, Siobhan

1999-01-01

Focuses on Allen O. Hansen's "Liberalism and American Education in the Eighteenth Century" and Frederick Rudolph's "Essays on Education in the Early Republic." Explores the influence of Hansen and Rudolph on other works of educational thought. Contends that a more accurate picture of the early republic is needed. (CMK)

Developing Conceptual Understanding of Fractions with Year Five and Six Students

ERIC Educational Resources Information Center

Mills, Judith

2016-01-01

This paper presents findings from classroom observations of one teacher (Beth). It focusses on the development of conceptual understanding of fractions with her students, articulated in Kieren's sub-constructs (Kieren, 1980,1988), and Hansen's progressions (Hansen, 2005). The study covers three lessons within a six week unit. Findings from this…

Performance Characterization of the Free Molecule Micro-Resistojet Utilizing Water Propellant (Preprint)

DTIC Science & Technology

2007-05-24

187, pp. 45-137, 2000. 3. Janson, S., Helvajian , H ., Hansen, W., and Lodmell, J. “Microthrusters for Nanosatellites,” The Second International...spherical propellant tank is given by ( )2 21 33e e t eV h r hπ= + (1) Where the resulting height of the propellant is 2p t eh r h = − (2) A...correlation between p t h r and w m M is found in ref. 10. For the parameters of the TD, the resulting mass of the sloshing waves prior to the burn

Further Extending the Humanistic Vision for the Future of Counseling: A Response to Hansen

ERIC Educational Resources Information Center

Brady-Amoon, Peggy

2012-01-01

This article offers additional support for Hansen's (2012) position that humanism and a renewed respect for human complexity are essential to counseling. In the article, the author also speaks to the critical importance of continuing to ground the profession in art and science. Implications for the future of humanism and counseling are presented.

78 FR 19477 - Public Service Company of Colorado; Notice of Settlement Agreement and Soliciting Comments

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-01

... Application: Settlement Agreement. b. Project No.: P-2351-017. c. Date filed: March 22, 2013. d. Applicant... the Commission's Rules of Practice and Procedure, 18 CFR 385.602. h. Applicant Contact: Christine E... Hansen, (202) 502-8074, ryan.hansen@ferc.gov . j. Deadline for filing comments: 20 days from the filing...

Publications - SR 47 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

and Facilities Staff Seismic and Well Data Data Reports Contact Us Frequently Asked Questions Ask a , T.K., Clough, A.H., Hansen, E.W., and Nelson, M.G. Publication Date: 1993 Publisher: Alaska Division ., Clough, A.H., Hansen, E.W., and Nelson, M.G., 1993, Alaska's mineral industry 1992: Alaska Division of

Assessment of the Thermodynamic Properties of DL-p-Mentha-1,8-diene, 4-Isopropyl-1-Methylcyclohexene (DL-limonene) by Inverse Gas Chromatography (IGC).

PubMed

Farshchi, Negin; Abbasian, Ali; Larijani, Kambiz

2018-05-10

Limonene is a colorless liquid hydrocarbon and had been investigated as a plasticizer for many plastics. Prediction of solubility between different materials is an advantage in many ways, one of the most convenient ways to know the compatibility of materials is to determine the degree of solubility of them in each other. The concept of "solubility parameter" can help practitioners in this way.In this study, inverse gas chromatography (IGC) method at infinite dilution was used for determination of the thermodynamic properties of DL-p-mentha-1,8-diene, 4-Isopropyl-1-methylcyclohexene (DL-limonene). The interaction between DL-limonene and 13 solvents were examined in the temperature range of 63-123°C through the assessment of the thermodynamic sorption parameters, the parameters of mixing at infinite dilution, the weight fraction activity coefficient and the Flory-Huggins interaction parameters. Additionally, the solubility parameter for DL-limonene and the temperature dependence of these parameters was investigated as well.Results show that there is a temperature dependence in solubility parameter, which increases by decreasing temperature. However, there were no specific dependence between interaction parameters and temperature, but chemical structure appeared to have a significant effect on them as well as on the type and strength of intermolecular interactions between DL-limonene and investigated solvents. The solubility parameter δ2 of DL-limonene determined to be 19.20 (J/cm3)0.5 at 25°C.

Results of SEI Independent Research and Development Projects

DTIC Science & Technology

2009-12-01

Achieving Predictable Performance in Multicore Embedded Real - Time Systems Dionisio de Niz, Jeffrey Hansen, Gabriel Moreno, Daniel Plakosh, Jorgen Hanson...Description Languages.‖ Fourth Congress on Embedded Real - Time Systems (ERTS), January 2008. [Hansson 2008b] J. Hansson, P. H. Feiler, & J. Morley...Predictable Performance in Multicore Embedded Real - Time Systems Dionisio de Niz, Jeffrey Hansen, Gabriel Moreno, Daniel Plakosh, Jorgen Hanson, Mark

Modeling Second Language Change Using Skill Retention Theory

DTIC Science & Technology

2013-06-01

xiv LIST OF TABLES Table 1. ILR and ACTFL Scale Comparison (From SIL International, 1999) ................5 Table 2. Metacognitive Learning Strategy...meaningful. • Speaking and writing are productive skill and require that a linguist actively produce information to be conveyed. E. RESEARCH...before productive skills (speaking and writing ) and attrition of these skills takes place in reverse order (Hansen & Reetz-Kurashige, 1999). Hansen

76 FR 76705 - Inside Passage Electric Cooperative; Notice of Intent To File License Application, Filing of Pre...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-08

... Application and Request to Use the Traditional Licensing Process. b. Project No.: 14066-001. c. Date Filed... regulations. h. Potential Applicant Contact: Peter Bibb, Inside Passage Electric Cooperative, P.O. Box 210149... Hansen at (202) 502-8074; or email at ryan.hansen@ferc.gov . j. IPEC filed its request to use the...

76 FR 9005 - David Creasey; Notice of Application Tendered for Filing With the Commission; Notice of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-16

... for public inspection. a. Type of Application: Original Minor License. b. Project No.: 13829-001. c... property owned by the applicant. h. Filed Pursuant to: 18 CFR 4.61 of the Commission's regulations. i... Hansen, (202) 502-8074, or e-mail at ryan.hansen@ferc.gov . k. A copy of the application is available for...

Publications - SR 48 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

and Facilities Staff Seismic and Well Data Data Reports Contact Us Frequently Asked Questions Ask a , R.C., Clough, A.H., Henning, M.W., and Hansen, E.W. Publication Date: 1994 Publisher: Alaska Division ., Swainbank, R.C., Clough, A.H., Henning, M.W., and Hansen, E.W., 1994, Alaska's mineral industry 1993: Alaska

Publications - SR 49 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

and Facilities Staff Seismic and Well Data Data Reports Contact Us Frequently Asked Questions Ask a , T.K., Clough, A.H., Henning, M.W., and Hansen, E.W. Publication Date: 1995 Publisher: Alaska Division ., Bundtzen, T.K., Clough, A.H., Henning, M.W., and Hansen, E.W., 1995, Alaska's mineral industry 1994: Alaska

Evaluation of ENDF/B-IV and Hansen--Roach /sup 233/U cross sections for use in criticality calculations

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

McNeany, S.R.; Jenkins, J.D.

Eleven /sup 233/U solution critical assemblies spanning an H//sup 233/U ratio range of 40 to 2000 and an unreflected metal /sup 233/U assembly were calculated with ENDF/B-IV and Hansen--Roach cross sections. Results from these calculations are compared with the experimental results and with each other. An increasing disagreement is observed between calculations with ENDF/B and Hansen--Roach data with decreasing H//sup 233/U ratio, indicative of large differences in their intermediate-energy cross sections. The Hansen--Roach cross sections appeared to give reasonably good agreement with experiments over the whole range, whereas the ENDF/B calculations yielded high values for k/sub eff/ on assemblies ofmore » low moderation. It is concluded that serious problems exist in the ENDF/B-IV representation of the /sup 233/U cross sections in the intermediate energy range and that further evaluation of this nuclide is warranted. In addition, it is recommended that an experimental program be undertaken to obtain /sup 233/U criticality data at low H//sup 233/U ratios for verification of generalized criticality safety guidelines. 3 figures, 15 tables.« less

Advanced materials for 193-nm resists

NASA Astrophysics Data System (ADS)

Ushirogouchi, Tohru; Asakawa, Koji; Shida, Naomi; Okino, Takeshi; Saito, Satoshi; Funaki, Yoshinori; Takaragi, Akira; Tsutsumi, Kentaro; Nakano, Tatsuya

2000-06-01

Acrylate monomers containing alicyclic side chains featuring a series of polar substituent groups were assumed to be model compounds. Solubility parameters were calculated for the corresponding acrylate polymers. These acrylate monomers were synthesized using a novel aerobic oxidation reaction employing N-hydroxyphtalimide (NHPI) as a catalyst, and then polymerized. These reactions were confirmed to be applicable for the mass-production of those compounds. The calculation results agreed with the hydrophilic parameters measured experimentally. Moreover, the relationship between the resist performance and the above-mentioned solubility parameter has been studied. As a result, a correlation between the resist performance and the calculated solubility parameter was observed. Finally, resolution of 0.13-micron patterns, based on the 1G DRAM design rule, could be successfully fabricated by optimizing the solubility parameter and the resist composition.

[Immune response of Hansen's disease. Review].

PubMed

Rada, Elsa; Aranzazu, Nacarid; Convit, Jacinto

2009-12-01

Hansen's disease presents a wide spectrum of clinical and histopathological manifestations that reflect the nature of the immunological response of the host towards diverse Mycobacterium leprae components. The immunological system, composed by both innate and adaptive immunology, offers protection towards infections of various etiologies, among them bacterial. Bacteria, of course, have developed multiple strategies for evading host defenses, based on either very complex or simple mechanisms, but with a single purpose: to "resist" host attacks and to be able to survive. We have tried to summarize some recent studies in Hansen's disease, with more emphasis in the inmunology area. We think that in the future, all illnesses should also be very strongly related to other important aspects such as the social, environmental and economic, and whose development is not solved in a laboratory.

Estimating terpene and terpenoid emissions from conifer oleoresin composition

NASA Astrophysics Data System (ADS)

Flores, Rosa M.; Doskey, Paul V.

2015-07-01

The following algorithm, which is based on the thermodynamics of nonelectrolyte partitioning, was developed to predict emission rates of terpenes and terpenoids from specific storage sites in conifers: Ei =xoriγoripi∘ where Ei is the emission rate (μg C gdw-1 h-1) and pi∘ is the vapor pressure (mm Hg) of the pure liquid terpene or terpenoid, respectively, and xori and γori are the mole fraction and activity coefficient (on a Raoult's law convention), respectively, of the terpene and terpenoid in the oleoresin. Activity coefficients are calculated with Hansen solubility parameters that account for dispersive, polar, and H-bonding interactions of the solutes with the oleoresin matrix. Estimates of pi∘ at 25 °C and molar enthalpies of vaporization are made with the SIMPOL.1 method and are used to estimate pi∘ at environmentally relevant temperatures. Estimated mixing ratios of terpenes and terpenols were comparatively higher above resin-acid- and monoterpene-rich oleoresins, respectively. The results indicated a greater affinity of terpenes and terpenols for the non-functionalized and carboxylic acid containing matrix through dispersive and H-bonding interactions, which are expressed in the emission algorithm by the activity coefficient. The correlation between measured emission rates of terpenes and terpenoids for Pinus strobus and emission rates predicted with the algorithm were very good (R = 0.95). Standard errors for the range and average of monoterpene emission rates were ±6 - ±86% and ±54%, respectively, and were similar in magnitude to reported standard deviations of monoterpene composition of foliar oils (±38 - ±51% and ±67%, respectively).

An enquiry on appropriate selection of polymers for preparation of polymeric nanosorbents and nanofiltration/ultrafiltration membranes for hormone micropollutants removal from water effluents.

PubMed

Khansary, Milad Asgarpour; Mellat, Mostafa; Saadat, Seyed Hassan; Fasihi-Ramandi, Mahdi; Kamali, Mehdi; Taheri, Ramezan Ali

2017-02-01

To analyze polymeric nanosorbents and nanofiltration/ultrafiltration membranes for hormone micropollutants removal from water effluents, here an in-through investigation on the suitability and compatibility of various polymers has been carried out. For this work, estradiol, estrone, testosterone, progesterone, estriol, mestranol, and ethinylestradiol were considered. A total number of 452 polymers were analyzed and initially screened using Hansen solubility parameters. The identified good pairs of hormones and polymers then were examined to obtain the equilibrium capacity of hormones removal from water effluents using a modified Flory-Huggins model. A distribution coefficient was defined as the ratio of hormones in water effluent phase and polymer phase. For removal of mestranol, estradiol and ethinylestradiol, no compatible polymer was identified based on initial screening of collected database. Three compatible polymers were identified for estriol. For progesterone, a wide variety of polymers was identified as good matching of polar, dispersion and hydrogen forces contributions can be observed for these pairs. For estrone, only two polymers can be proposed due to the mismatch observed between polar, dispersion and hydrogen forces contributions of other polymers and this hormone. The phase calculations showed that not all the identified good pairs could be used for practical separation applications. The domain of applicability of each good pair was investigated and potential polymers for practical micropollutants removal together with their removal capacity were represented in terms of phase envelops. The theoretical approach follows fundamental chemical thermodynamic equations and then can be simply applied for any system of interest. Copyright © 2016 Elsevier Ltd. All rights reserved.

Solvent Effects of Model Polymeric Corrosion Control Coatings on Water Transport and Corrosion Rate

NASA Astrophysics Data System (ADS)

Konecki, Christina

Industrial coating formulations are often made for volatile organic content compliance and ease of application, with little regard for the solvent impact on resultant performance characteristics. Our research objective was to understand the effect of both solvent retention and chemical structure on water transport through polymer films and resultant corrosion area growth of coated steel substrates. A clear, unpigmented Phenoxy(TM) thermoplastic polymer (PKHH) was formulated into resin solutions with three separate solvent blends selected by Hansen solubility parameter (HSP), boiling point, and ability to solubilize PKHH. Polymer films cast from MEK/PGME (methyl ethyl ketone/ propylene glycol methyl ether), dried under ambient conditions (AMB, > 6wt.% residual solvent) produced a porous morphology, which resulted in a corrosion area greater than 50%. We attributed this to the water-soluble solvent used in film preparation, which enabled residual PGME to be extracted by water. The resin solution prepared with CYCOH/DXL (Cyclohexanol/ 1,3 dioxolane) was selected because CYCOH is a solid at room temperature which acts as a pigment in the final film. Therefore, increasing the tortuosity of water transport, as well as a high hydrogen bonding character, which caused more interactions with water, slowing diffusion, producing a nodular morphology, and 37% less corrosion area than MEK/PGME AMB. The HSP of PKHH and EEP (ethyl 3-ethoxypropionate) are within 5% of each other, which produced a homogeneous morphology and resulted in comparable corrosion rates regardless of residual solvent content. We utilized electrochemical techniques and attenuated total reflectance- Fourier transform infrared spectroscopy to elucidate dynamic water absorption and solvent extraction in the exposed model formulations. We found that water absorption resulted in a loss of barrier properties, and increased corrosion due to the voids formed by solvent extraction. The polymer films were rejuvenated (removal of water) as an attempt to decrease the number of water transport pathways during exposure. Results found that samples rejuvenated at temperatures above the glass transition temperature of the samples achieved lower moisture content and consequently, lower corrosion growth rates. In commercial systems, rejuvenation lowered the corrosion rate up to 60% indicating better coating formulations and maintenance cycles would control the corrosion rate.

The Function of Scientific and Humanistic Ideologies in the Counseling Profession from the Perspective of Cognitive-Experiential Self-Theory: A Response to Hansen

ERIC Educational Resources Information Center

Suthakaran, V.

2012-01-01

In this response, the author addresses Hansen's (2012) call for the counseling profession to substitute science with humanities as its primary ideology. The author uses Epstein's (1994) cognitive-experiential self-theory to show that an equal appreciation for science and humanities is more congruent with a holistic humanistic vision for…

77 FR 53187 - Advisory Council on Dependents' Education; Notice of Open Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-31

..., from 2 a.m. to 6 a.m., Hawaii-Aleutian Standard Time (H-AST); Peachtree City, Georgia, from 8 a.m. to..., Georgia. FOR FURTHER INFORMATION CONTACT: Mr. Joel K. Hansen at (571) 372-5812 or Joel.Hansen@hq.dodea.edu... before the Council. Public Accessibility to the Meeting: Pursuant to 5 U.S.C. 552b and 41 CFR 102-3.140...

76 FR 14388 - David Creasey; Notice of Application Tendered for Filing With the Commission, Accepted for Filing...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-16

... No.: 13829-001. c. Date filed: February 4, 2011. d. Applicant: David Creasey. e. Name of Project... on private property owned by the applicant. h. Filed Pursuant to: 18 CFR 4.61 of the Commission's.... FERC Contact: Ryan Hansen, (202) 502-8074, or e-mail at ryan.hansen@ferc.gov . k. A copy of the...

Erratum: Hansen et al (2014).

PubMed

2015-04-01

In the article by Hansen AW, Dahl-Petersen I, Helge JW, et al, "Validation of an Internet-Based Long Version of the International Physical Activity Questionnaire in Danish Adults Using Combined Accelerometry and Heart Rate Monitoring," in J Phys Act Health, 11(3), p. 654, the DOI was listed incorrectly (10.1123/jpah.2012-0040a). This error has been fixed. The publisher apologizes for the error.

A method for estimating both the solubility parameters and molar volumes of liquids

NASA Technical Reports Server (NTRS)

Fedors, R. F.

1974-01-01

Development of an indirect method of estimating the solubility parameter of high molecular weight polymers. The proposed method of estimating the solubility parameter, like Small's method, is based on group additive constants, but is believed to be superior to Small's method for two reasons: (1) the contribution of a much larger number of functional groups have been evaluated, and (2) the method requires only a knowledge of structural formula of the compound.

Off-Range Beaked Whale Studies (ORBS): Baseline Data and Tagging Development for Northern Bottlenose Whales (Hyperoodon ampulatus) off Jan Mayen, Norway

DTIC Science & Technology

2015-09-30

02.003’N, 07°01.981’W) To be recovered in 2016 Ranging code #08D1; releasing code #0803 In collaboration with Rune Hansen of the University of...the animal with PTT 134760 was tracked moving all the way south to the Azores Archipelago. Figure courtesy of Rune Hansen. Objective 4. conduct

Hansen, Murphy, Receive Mineral and Rock Physics Graduate Research Awards

NASA Astrophysics Data System (ADS)

2014-08-01

Lars N. Hansen and Caitlin A. Murphy were awarded the 2013 Mineral and Rock Physics Graduate Research Award, given annually to one or more promising young scientists for outstanding contributions achieved during their Ph.D. research. Recipients of this award are engaged in experimental and/or theoretical studies of Earth and planetary materials with the purpose of unraveling the physics and chemistry that govern their origin and physical properties.

Neural Computation as a Tool to Differentiate Perceptual from Emotional Processes: The Case of Anger Superiority Effect

ERIC Educational Resources Information Center

Mermillod, Martial; Vermeulen, Nicolas; Lundqvist, Daniel; Niedenthal, Paula M.

2009-01-01

Research findings in social and cognitive psychology imply that it is easier to detect angry faces than happy faces in a crowd of neutral faces [Hansen, C. H., & Hansen, R. D. (1988). Finding the face in the crowd--An anger superiority effect. "Journal of Personality and Social Psychology," 54(6), 917-924]. This phenomenon has been held to have…

Modeling of central reactivity worth measurements in Lady Godiva

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

Wenz, T.R.; Busch, R.D.

The central reactivity worth measurements performed in Lady Godiva were duplicated using TWODANT, a deterministic neutron transport code, and the 16-group Hansen-Roach cross-section library. The purpose of this work was to determine how well the Hansen-Roach library predicts the reactivity worths for a fast neutron system. Lady Godiva is a spherical uranium metal (93.7 wt% [sup 235]U) critical assembly with a neutron flux distribution dominant in the first five groups of the Hansen-Roach energy structure (0.1 MeV and up). Provided that the cross sections of the replacement material do not undergo large variations (less than an order of magnitude) inmore » any of the aforementioned groups, the calculated reactivities were within 10% of the experimental values. For cases where the reactivities were outside this range, a large variation in the cross section was found to exist in one of the groups, which was not fully accounted for in the Hansen-Roach group structure. However, even in the cases where the agreement between calculation and experiment was not good, the calculated reactivity appeared to be an extremum in that the effect was found to be either more negative or more positive than the experimental value.« less

U.S. Navy-ASEE Summer Faculty Research Program. Abstracts 1987 - 1991

DTIC Science & Technology

1991-01-01

the WDrost-Hansen (thermal anomaly ) temperatures"); Drost-Hansen, 1969. 3. The rate of compaction, in the earlystages of this process, is also strongly...in a non- magnetic environment for determining underwater acoustic waves. The AM and homodyne probes used a cooled photomultiple take as the detector...of magnetic data and the Gauss-Schmidt coefficients for multi-years remains to be considered. A supercomputer is preferable for the stochastic

Characterization of Particulate Emissions: Size Fractionation and Chemical Speciation

DTIC Science & Technology

2003-10-01

Absorption by Aerosols. Aerosol Science and Technology 30(6) 1999 582-600. Hansen, A.D.A., H. Rosen, T. Novakov (1984). The Aethalometer - An...towards increasing levels of BC production ( Novakov , Ramanathan et al. 2003). It is unhealthy to breath the polycyclic aromatic hydrocarbons that... Novakov , T., V. Ramanathan, J. E. Hansen, T. W. Kirchstetter, M. Sato, J. E. Sinton and J. A. Sathaye (2003). "Large historical changes of fossil

Gas sorption and barrier properties of polymeric membranes from molecular dynamics and Monte Carlo simulations.

PubMed

Cozmuta, Ioana; Blanco, Mario; Goddard, William A

2007-03-29

It is important for many industrial processes to design new materials with improved selective permeability properties. Besides diffusion, the molecule's solubility contributes largely to the overall permeation process. This study presents a method to calculate solubility coefficients of gases such as O2, H2O (vapor), N2, and CO2 in polymeric matrices from simulation methods (Molecular Dynamics and Monte Carlo) using first principle predictions. The generation and equilibration (annealing) of five polymer models (polypropylene, polyvinyl alcohol, polyvinyl dichloride, polyvinyl chloride-trifluoroethylene, and polyethylene terephtalate) are extensively described. For each polymer, the average density and Hansen solubilities over a set of ten samples compare well with experimental data. For polyethylene terephtalate, the average properties between a small (n = 10) and a large (n = 100) set are compared. Boltzmann averages and probability density distributions of binding and strain energies indicate that the smaller set is biased in sampling configurations with higher energies. However, the sample with the lowest cohesive energy density from the smaller set is representative of the average of the larger set. Density-wise, low molecular weight polymers tend to have on average lower densities. Infinite molecular weight samples do however provide a very good representation of the experimental density. Solubility constants calculated with two ensembles (grand canonical and Henry's constant) are equivalent within 20%. For each polymer sample, the solubility constant is then calculated using the faster (10x) Henry's constant ensemble (HCE) from 150 ps of NPT dynamics of the polymer matrix. The influence of various factors (bad contact fraction, number of iterations) on the accuracy of Henry's constant is discussed. To validate the calculations against experimental results, the solubilities of nitrogen and carbon dioxide in polypropylene are examined over a range of temperatures between 250 and 650 K. The magnitudes of the calculated solubilities agree well with experimental results, and the trends with temperature are predicted correctly. The HCE method is used to predict the solubility constants at 298 K of water vapor and oxygen. The water vapor solubilities follow more closely the experimental trend of permeabilities, both ranging over 4 orders of magnitude. For oxygen, the calculated values do not follow entirely the experimental trend of permeabilities, most probably because at this temperature some of the polymers are in the glassy regime and thus are diffusion dominated. Our study also concludes large confidence limits are associated with the calculated Henry's constants. By investigating several factors (terminal ends of the polymer chains, void distribution, etc.), we conclude that the large confidence limits are intimately related to the polymer's conformational changes caused by thermal fluctuations and have to be regarded--at least at microscale--as a characteristic of each polymer and the nature of its interaction with the solute. Reducing the mobility of the polymer matrix as well as controlling the distribution of the free (occupiable) volume would act as mechanisms toward lowering both the gas solubility and the diffusion coefficients.

[Determination of solubility parameters for asymmetrical dicationic ionic liquids by inverse gas chromatography].

PubMed

Wang, Jun; Yang, Xuzhao; Wu, Jinchao; Song, Hao; Zou, Wenyuan

2015-12-01

Inverse gas chromatographic (IGC) technology was used to determine the solubility parameters of three asymmetrical dicationic ionic liquids ([ PyC5Pi] [ NTf2]2, [MpC5Pi] [NTf2]2 and [PyC6Pi] [NTf2]2) at 343.15-363.15 K. Five alkanes were applied as test probes including octane (n-C8) , decane (n-C10), dodecane (n-C12), tetradecane (n-C14), hexadecane (n-C16). Some thermodynamic parameters were obtained by IGC data analysis, such as the specific retention volumes of the solvents (V0(g)), the molar enthalpies of sorption (ΔHs(1)), the partial molar enthalpies of mixing at infinite dilution (ΔH∞91)), the molar enthalpies of vaporization (ΔH)v)), the activity coefficients at infinite dilution (Ω∞(1)), and Flory-Huggins interaction parameters (χ∞(12)) between ionic liquids and probes. The solubility parameters (δ2) of the three dicationic ionic liquids at room temperature (298.15 K) were 28.52-32.66 (J x cm(-3)) ½. The solubility parameters (δ2) of cationic structure with 4-methyl morpholine are bigger than those of the cationic structure with pyridine. The bigger the solubility parameter (δ2) is, the more the carbon numbers of linking group of the ionic liquids are. The results are of great importance to the study of the solution behavior and the applications of ionic liquid.

Prediction of solubility parameters and miscibility of pharmaceutical compounds by molecular dynamics simulations.

PubMed

Gupta, Jasmine; Nunes, Cletus; Vyas, Shyam; Jonnalagadda, Sriramakamal

2011-03-10

The objectives of this study were (i) to develop a computational model based on molecular dynamics technique to predict the miscibility of indomethacin in carriers (polyethylene oxide, glucose, and sucrose) and (ii) to experimentally verify the in silico predictions by characterizing the drug-carrier mixtures using thermoanalytical techniques. Molecular dynamics (MD) simulations were performed using the COMPASS force field, and the cohesive energy density and the solubility parameters were determined for the model compounds. The magnitude of difference in the solubility parameters of drug and carrier is indicative of their miscibility. The MD simulations predicted indomethacin to be miscible with polyethylene oxide and to be borderline miscible with sucrose and immiscible with glucose. The solubility parameter values obtained using the MD simulations values were in reasonable agreement with those calculated using group contribution methods. Differential scanning calorimetry showed melting point depression of polyethylene oxide with increasing levels of indomethacin accompanied by peak broadening, confirming miscibility. In contrast, thermal analysis of blends of indomethacin with sucrose and glucose verified general immiscibility. The findings demonstrate that molecular modeling is a powerful technique for determining the solubility parameters and predicting miscibility of pharmaceutical compounds. © 2011 American Chemical Society

User Guide for Characterizing Particulate Matter. Evaluation of Several Real-Time Methods. Appendix 1

DTIC Science & Technology

2003-10-01

Hansen, A.D.A., H. Rosen, T. Novakov (1984). The Aethalometer - An Instrument for the Real-Time Measurement of Optical Absorption by Aerosol Particles...hydrological cycles (Ramanathan and Crutzen 2003). Historical trends point towards increasing levels of BC production ( Novakov , Ramanathan et al. 2003...immunology : official organ of American Academy of Allergy 102(4 1): 539-554. Novakov , T., V. Ramanathan, J. E. Hansen, T. W. Kirchstetter, M. Sato, J. E

Assertion Mechanisms in Programming Languages.

DTIC Science & Technology

1979-11-01

the Construction and Verific3tion of ALPHAPD Programs ", IEEE Transactions on Software Engineering , voL. 2, no. 4, p. 253-265, 1 1-7t [Zelkooitz a...be true at a point in program execut ion. The languaje designer has several options when considering the semantics of an assertion mechanism... Software Engineering , vol. SE-i, no. 2, p. 156-173, June 1975. [Hansen] G. J. Hansen, G. A. Shoults and J. D. Coinmeat, "Construction of a Transportaole

PETROLEUM RESIDUA SOLUBILITY PARAMETER/POLARITY MAP: STABILITY STUDIES OF RESIDUA PYROLYSIS

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

John F. Schabron; A. Troy Pauli; Joseph F. Rovani, Jr.

1999-04-30

A new molecular weight/polarity map based on the Scatchard-Hildebrand solubility equation has been developed for petroleum residua. A series of extractions are performed with solvents of increasing solubility parameter, and the fractions are analyzed by vapor pressure osmometry for number average molecular weight and by analytical-scale size exclusion chromatography for molecular weight spread. Work was performed for a heavy oil material subjected to three increasing severities of thermal treatment prior to and through the onset of coke formation. The results are diagnostic of the layers of solvations by resin-type molecules around a central asphaltene core. Two additional stability diagnostic methodsmore » were also used. These were the Heithaus titration ''P-index'' and Gaestel ''G'' index, which have been applied to paving asphalts for decades. The Heithaus titration involves the titration of three toluene solutions of a residuum at three concentrations with a poor solvent, such as isooctane, to the point of asphaltene flocculation. In the present work, the significance of the data are developed in terms of the Hildebrand solubility parameter. The Heithaus results are combined with data from the new molecular weight/polarity map. The solubility parameters for the toluene-soluble asphaltene components are measured, and the solubility parameters of the maltenes can be calculated. As thermal treatment progresses, the solubility parameters of asphaltene materials increase and the molecular weights decrease. A new coking index is proposed based on Heithaus titration data. Preliminary results suggest that an alternative, simpler coking index may be developed by measuring the weight percent of cyclohexane solubles in heptane asphaltenes. Coking onset appears to coincide with the depletion of these resin-type asphaltene solubilizing components of residua. The objective of the present study was to develop a mapping tool that will enhance understanding of the changes that occur in residua during upgrading and support the industry-sponsored work in which Western Research Institute is engaged. WRI performs proprietary industry-sponsored residua and heavy oil upgrading process development and optimization research. The new mapping tool can be used for evaluating heavy oils and residua in both upstream and downstream operations.« less

Simultaneous cell disruption and lipid extraction of wet aurantiochytrium sp. KRS101 using a high shear mixer.

PubMed

Kwak, Minsoo; Kang, Seul Gi; Hong, Won-Kyung; Han, Jong-In; Chang, Yong Keun

2018-05-01

Microalgae are regarded as a promising source of biofuels, and the concept of a microalgae-based biorefinery has attracted increasing attention in recent years. From an economic perspective, however, the process remains far from competitive with fossil fuels. This is particularly true of lipid extraction, due in part to the energy-intensive drying step. As a result, wet extraction methods have been studied as an economic alternative. In the present study, a novel extraction approach which utilizes high shear stress mixing was adopted and demonstrated for simultaneous lipid extraction and cell disruption to enable the retrieval of lipids directly from concentrated wet biomass. When a high shear mixer (HSM) was used to extract lipid from a dense biomass (> 350 g/L) of the oleaginous algae Aurantiochytrium sp., it exhibited a yield of esterifiable lipids which exceeded 80% in 10 min at 15,000 rpm with various solvent types. The HSM was found to improve the lipid yields substantially with solvents less miscible with either lipids or water, such that the range of Hansen solubility parameters for the usable solvents became 3.3 times wider (14.9-26.5 MPa 1/2 ). The HSM, which appeared effectively to loosen the water barrier that prevents solvent molecules from penetrating through the cell envelope, was found to be more efficient with hexane, hexane/isopropanol, and ethanol, all of which showed nearly identical lipid yields compared to the dry extraction process. The HSM can, indeed, offer a powerful mechanical means of lipid extraction with non-polar and less toxic solvents from wet biomass.

On the classification of exoplanets according to Safronov number

NASA Astrophysics Data System (ADS)

Öztürk, O.; Erdem, A.

2018-02-01

We reexamine the classification of transiting exoplanets proposed by Hansen & Barman (2007) based on equilibrium temperatures and Safronov numbers. We used more sensitive data, namely, photometric and spectroscopic orbital solutions, of 263 well-known planets given in The Exoplanet Data Explorer, while Hansen & Barman (2007) used data on 18 transiting planets. Diagrams of the planet gravity vs. orbital period, planet gravity vs. equilibrium temperature, and Safronov number vs. equilibrium temperature of the 263 transiting planets show that the division of planets into two classes is indistinct.

Analysis and Thermodynamic Prediction of Hydrogen Solution in Solid and Liquid Multicomponent Aluminum Alloys

NASA Astrophysics Data System (ADS)

Anyalebechi, P. N.

Reported experimentally determined values of hydrogen solubility in liquid and solid Al-H and Al-H-X (where X = Cu, Si, Zn, Mg, Li, Fe or Ti) systems have been critically reviewed and analyzed in terms of Wagner's interaction parameter. An attempt has been made to use Wagner's interaction parameter and statistic linear regression models derived from reported hydrogen solubility limits for binary aluminum alloys to predict the hydrogen solubility limits in liquid and solid (commercial) multicomponent aluminum alloys. Reasons for the observed poor agreement between the predicted and experimentally determined hydrogen solubility limits are discussed.

[Diagnosis of Hansen's disease].

PubMed

Yotsu, Rie Roselyne; Suzuki, Koichi; Mori, Shuichi; Ishii, Norihisa

2011-02-01

The Leprosy Mailing List (LML) is an e-mailing list open to whoever interested in the field from all over the world. It acts as a forum for exchanging information related to Hansen's disease. It was established in February 2001 in Italy, and the present moderator of the LML is Dr. Salvatore Noto. He and his colleague have recently introduced an atlas for diagnosing Hansen's disease which they brought together information and photos collected through the LML. The atlas is divided into three sections, (1) Introduction, (2) Cardinal signs, and (3) Diagnosis and the clinical spectrum of leprosy, and they are all accompanied with relevant photos. This time, Dr. Noto kindly permitted us to translate the atlas into Japanese to be published in the Japanese Journal of Leprosy and posted in the Japanese Leprosy Association homepage. This article includes the translation and some of the most informative photos. For more information, please refer to the homepage where you will find all photos in the atlas.

Evaluation of a continual compliance monitoring program for dapsone in an outpatient Hansen's disease clinic.

PubMed

Fischer, J H; West, D P; Worobec, S M

1986-12-01

Guidelines for the assessment of patient compliance to dapsone were developed and evaluated. The urinary dapsone-to-creatinine (D/C) ratio following standardization by dose, ideal body weight, and time since last dose was used for assessment of compliance. Compliance standards were established in 12 patients of known compliance and confirmed prospectively in nine inpatients on 14 occasions. Compliance increased significantly among outpatients (N = 30) attending the University of Illinois Hansen's Disease Clinic from 47% at base line to 73% at 6 months and 80% at 18 months after establishing the monitoring program. In a subgroup of 18 patients, a similar increase in compliance was observed from 50% to 80%. A good therapeutic response was seen in the subgroup patients who were compliant. A poor therapeutic response was seen in the consistently noncompliant patients. These results demonstrate that use of a continual compliance monitoring program can improve patient drug compliance in an outpatient Hansen's disease clinic.

More efficient evolutionary strategies for model calibration with watershed model for demonstration

NASA Astrophysics Data System (ADS)

Baggett, J. S.; Skahill, B. E.

2008-12-01

Evolutionary strategies allow automatic calibration of more complex models than traditional gradient based approaches, but they are more computationally intensive. We present several efficiency enhancements for evolution strategies, many of which are not new, but when combined have been shown to dramatically decrease the number of model runs required for calibration of synthetic problems. To reduce the number of expensive model runs we employ a surrogate objective function for an adaptively determined fraction of the population at each generation (Kern et al., 2006). We demonstrate improvements to the adaptive ranking strategy that increase its efficiency while sacrificing little reliability and further reduce the number of model runs required in densely sampled parts of parameter space. Furthermore, we include a gradient individual in each generation that is usually not selected when the search is in a global phase or when the derivatives are poorly approximated, but when selected near a smooth local minimum can dramatically increase convergence speed (Tahk et al., 2007). Finally, the selection of the gradient individual is used to adapt the size of the population near local minima. We show, by incorporating these enhancements into the Covariance Matrix Adaption Evolution Strategy (CMAES; Hansen, 2006), that their synergetic effect is greater than their individual parts. This hybrid evolutionary strategy exploits smooth structure when it is present but degrades to an ordinary evolutionary strategy, at worst, if smoothness is not present. Calibration of 2D-3D synthetic models with the modified CMAES requires approximately 10%-25% of the model runs of ordinary CMAES. Preliminary demonstration of this hybrid strategy will be shown for watershed model calibration problems. Hansen, N. (2006). The CMA Evolution Strategy: A Comparing Review. In J.A. Lozano, P. Larrañga, I. Inza and E. Bengoetxea (Eds.). Towards a new evolutionary computation. Advances in estimation of distribution algorithms. pp. 75-102, Springer Kern, S., N. Hansen and P. Koumoutsakos (2006). Local Meta-Models for Optimization Using Evolution Strategies. In Ninth International Conference on Parallel Problem Solving from Nature PPSN IX, Proceedings, pp.939-948, Berlin: Springer. Tahk, M., Woo, H., and Park. M, (2007). A hybrid optimization of evolutionary and gradient search. Engineering Optimization, (39), 87-104.

Solubility parameters of hypromellose acetate succinate and plasticization in dry coating procedures.

PubMed

Klar, Fabian; Urbanetz, Nora Anne

2016-10-01

Solubility parameters of HPMCAS have not yet been investigated intensively. On this account, total and three-dimensional solubility parameters of HPMCAS were determined by using different experimental as well as computational methods. In addition, solubility properties of HPMCAS in a huge number of solvents were tested and a Teas plot for HPMCAS was created. The total solubility parameter of about 24 MPa(0.5) was confirmed by various procedures and compared with values of plasticizers. Twenty common pharmaceutical plasticizers were evaluated in terms of their suitability for supporting film formation of HPMCAS under dry coating conditions. Therefore, glass transition temperatures of mixtures of polymer and plasticizers were inspected and film formation of potential ones was further investigated in dry coating of pellets. Contact angles of plasticizers on HPMCAS were determined in order to give a hint of achievable coating efficiencies in dry coating, but none was found to spread on HPMCAS. A few common substances, e.g. dimethyl phthalate, glycerol monocaprylate, and polyethylene glycol 400, enabled plasticization of HPMCAS; however, only triethyl citrate and triacetin were found to be suitable for use in dry coating. Addition of acetylated monoglycerides to triacetin increased coating efficiency, which was likewise previously demonstrated for triethyl citrate.

The brilliant blue FCF ion-molecular forms in solutions according to the spectrophotometry data

NASA Astrophysics Data System (ADS)

Chebotarev, A. N.; Bevziuk, K. V.; Snigur, D. V.; Bazel, Ya. R.

2017-10-01

The brilliant blue FCF acid-base properties in aqueous solutions have been studied and its ionization constants have been defined by tristimulus colorimetry and spectrophotometry methods. The scheme of the acid-base dye equilibrium has been proposed and a diagram of the distribution of its ionic-molecular forms has been built. It has been established that the dominant form of the dye was the electroneutral form, which molar absorptivity (ɛ625 = 0.97 × 105) increases with the increase of the dielectric permittivity of the solvent. It has been shown that the replacement of polar solvents by less polar ones is causing a bathochromic shift of the maximum absorption band of the dye, the value of which is correlated with the value of the Hansen parameter. Tautomerization constants have been defined in a number of solvents and associated with the value of the Dimroth-Reichardt parameter.

Characterization of the surface tension and solubility parameter of epoxy resin by using inverse gas chromatography.

PubMed

Shi, Fenghui; Dai, Zhishuang; Zhang, Baoyan

2010-07-01

Inverse gas chromatography (IGC) was used to measure the surface tension and solubility parameter of E51 epoxy resin in this work. By using the Schultz method, decane, nonane, octane and heptane were chosen as the neutral probes to calculate the dispersive surface tensions (gamma(D)). Based on the Good-van Oss equation, the specific surface tension (gamma(SP)) of E51 epoxy resin was calculated with the acidic probe of dichloromethane and the basic probe of toluene. The results showed that the gamma(D) and gamma(SP) of the E51 resin decreased linearly with the increase of temperature. According to the Flory-Huggins parameters (chi) between the resin and a series of probes, the solubility parameters (delta) of E51 resin at different temperatures were estimated using the method developed by DiPaola-Baranyi and Guillet. It was found that the values of delta of the E51 resin were 11.78, 11.57, 11.48 and 11.14 MPa1/2 at 30, 40, 50 and 60 degrees C, respectively. The dispersive component (delta(D)) and the specific component (delta(SP)) of solubility parameter at different temperatures of the E51 resin were investigated according to the relationships between surface tension, cohesion energy and solubility parameter. The results showed that the values of delta(D) were higher than those of delta(SP) for the epoxy resin, and both of them decreased with the increase of temperature.

Echo 30" Sub Satellite

NASA Image and Video Library

2012-09-07

James Hansen describes the work on Project Echo s air density experiment known as the Sub-Satellite. Before launch engineers subjected the sub-satellite to many tests. Here, the sub-satellite is shown prior to tests to determine the capacity of the 30-inch Sub-Satellite to withstand the high temperature of direct sunlight in space, Langley researchers subjected it to 450 F heat test. Results indicated that the aluminum-covered Mylar plastic would effectively reflect the dangerous heat. -- Published in James R. Hansen, Spaceflight Revolution: NASA Langley Research Center From Sputnik to Apollo, NASA SP-4308, p. 168.

U.S. Army Corps of Engineers Recreation Study. A Plan Prepared for the Assistant Secretary of the Army (Civil Works). Volume 2. Appendices

DTIC Science & Technology

1990-09-01

TELEPHONE (Include Area Code) 22c OFFICE SYMBOL WILLIAM J. HANSEN (703) 355-3089 CEWRC-IWR-R DD FORM 1473, 84 MAR 83 APR edition may be used until... William J. Hansen of the Institute for Water Resources was the Technical Study Manager. Mr. L. Leigh Skaggs of the Institute for Water Resources...Mr. William Thornton, Missouri River Division, Mr. Bruce Hardie, Southwestern Division and Mr. Allen Summers, North Pacific Division. U.S. ARMY

VizieR Online Data Catalog: Simulation data for 50 planetary model systems (Hansen+, 2015)

NASA Astrophysics Data System (ADS)

Hansen, B. M. S.; Murray, N.

2017-11-01

We have used the results (after 10 Myr of evolution) of 50 model realizations of the 20 M{Earth} rocky planet systems from Hansen & Murray (2013ApJ...775...53H) to define the initial state of our systems, given in Table A1. We assume all the planets are of terrestrial class, in the sense that they obey the tidal dissipation, and evolve them for 10 Gyr according to our model for tidal+secular evolution. The final configurations are given in Table A2. (2 data files).

In vitro dynamic solubility test: influence of various parameters.

PubMed Central

Thélohan, S; de Meringo, A

1994-01-01

This article discusses the dissolution of mineral fibers in simulated physiological fluids (SPF), and the parameters that affect the solubility measurement in a dynamic test where an SPF runs through a cell containing fibers (Scholze and Conradt test). Solutions simulate either the extracellular fluid (pH 7.6) or the intracellular fluid (pH 4.5). The fibers have various chemical compositions and are either continuously drawn or processed as wool. The fiber solubility is determined by the amount of SiO2 (and occasionally other ions) released in the solution. Results are stated as percentage of the initial silica content released or as dissolution rate v in nm/day. The reproducibility of the test is higher with the less soluble fibers (10% solubility), than with highly soluble fibers (20% solubility). The influence of test parameters, including SPF, test duration, and surface area/volume (SA/V), has been studied. The pH and the inorganic buffer salts have a major influence: industrial glasswool composition is soluble at pH 7.6 but not at pH 4.5. The opposite is true for rock- (basalt) wool composition. For slightly soluble fibers, the dissolution rate v remains constant with time, whereas for highly soluble fibers, the dissolution rate decreases rapidly. The dissolution rates believed to occur are v1, initial dissolution rate, and v2, dissolution rate of the residual fibers. The SA of fibers varies with the mass of the fibers tested, or with the fiber diameter at equal mass. Volume, V, is the chosen flow rate. An increase in the SA/V ratio leads to a decrease in the dissolution rate.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7882964

In vitro dynamic solubility test: influence of various parameters.

PubMed

Thélohan, S; de Meringo, A

1994-10-01

This article discusses the dissolution of mineral fibers in simulated physiological fluids (SPF), and the parameters that affect the solubility measurement in a dynamic test where an SPF runs through a cell containing fibers (Scholze and Conradt test). Solutions simulate either the extracellular fluid (pH 7.6) or the intracellular fluid (pH 4.5). The fibers have various chemical compositions and are either continuously drawn or processed as wool. The fiber solubility is determined by the amount of SiO2 (and occasionally other ions) released in the solution. Results are stated as percentage of the initial silica content released or as dissolution rate v in nm/day. The reproducibility of the test is higher with the less soluble fibers (10% solubility), than with highly soluble fibers (20% solubility). The influence of test parameters, including SPF, test duration, and surface area/volume (SA/V), has been studied. The pH and the inorganic buffer salts have a major influence: industrial glasswool composition is soluble at pH 7.6 but not at pH 4.5. The opposite is true for rock- (basalt) wool composition. For slightly soluble fibers, the dissolution rate v remains constant with time, whereas for highly soluble fibers, the dissolution rate decreases rapidly. The dissolution rates believed to occur are v1, initial dissolution rate, and v2, dissolution rate of the residual fibers. The SA of fibers varies with the mass of the fibers tested, or with the fiber diameter at equal mass. Volume, V, is the chosen flow rate. An increase in the SA/V ratio leads to a decrease in the dissolution rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression, purification, and characterization of human acetyl-CoA carboxylase 2.

PubMed

Kim, Ki Won; Yamane, Harvey; Zondlo, James; Busby, James; Wang, Minghan

2007-05-01

The full-length human acetyl-CoA carboxylase 1 (ACC1) was expressed and purified to homogeneity by two separate groups (Y.G. Gu, M. Weitzberg, R.F. Clark, X. Xu, Q. Li, T. Zhang, T.M. Hansen, G. Liu, Z. Xin, X. Wang, T. McNally, H. Camp, B.A. Beutel, H.I. Sham, Synthesis and structure-activity relationships of N-{3-[2-(4-alkoxyphenoxy)thiazol-5-yl]-1-methylprop-2-ynyl}carboxy derivatives as selective acetyl-CoA carboxylase 2 inhibitors, J. Med. Chem. 49 (2006) 3770-3773; D. Cheng, C.H. Chu, L. Chen, J.N. Feder, G.A. Mintier, Y. Wu, J.W. Cook, M.R. Harpel, G.A. Locke, Y. An, J.K. Tamura, Expression, purification, and characterization of human and rat acetyl coenzyme A carboxylase (ACC) isozymes, Protein Expr. Purif., in press). However, neither group was successful in expressing the full-length ACC2 due to issues of solubility and expression levels. The two versions of recombinant human ACC2 in these reports are either truncated (lacking 1-148 aa) or have the N-terminal 275 aa replaced with the corresponding ACC1 region (1-133 aa). Despite the fact that ACC activity was observed in both cases, these constructs are not ideal because the N-terminal region of ACC2 could be important for the correct folding of the catalytic domains. Here, we report the high level expression and purification of full-length human ACC2 that lacks only the N-terminal membrane attachment sequence (1-20 and 1-26 aa, respectively) in Trichoplusia ni cells. In addition, we developed a sensitive HPLC assay to analyze the kinetic parameters of the recombinant enzyme. The recombinant enzyme is a soluble protein and has a K(m) value of 2 microM for acetyl-CoA, almost 30-fold lower than that reported for the truncated human ACC2. Our recombinant enzyme also has a lower K(m) value for ATP (K(m)=52 microM). Although this difference could be ascribed to different assay conditions, our data suggest that the longer human ACC2 produced in our system may have higher affinities for the substrates and could be more similar to the native enzyme.

Oil shale extraction using super-critical extraction

NASA Technical Reports Server (NTRS)

Compton, L. E. (Inventor)

1983-01-01

Significant improvement in oil shale extraction under supercritical conditions is provided by extracting the shale at a temperature below 400 C, such as from about 250 C to about 350 C, with a solvent having a Hildebrand solubility parameter within 1 to 2 Hb of the solubility parameter for oil shale bitumen.

The high throughput investigation of polyphenolic couplers in biodegradable packaging materials

NASA Astrophysics Data System (ADS)

Lochhead, Robert Y.; Haynes, Camille T.; Jones, Stephen R.; Smith, Virginia

2006-01-01

Our goal is to select and develop stimuli-responsive interfacial coupling materials for nanocomposites that will enhance substrate mechanical properties during use but cause triggered disintegration when exposed to the appropriate aqueous environment. The study could potentially provide the scientific underpinning for the development of an interfacially interacting nanocomposite alloy capable of enhanced biodegradation in the aqueous environment. In the first stage of this study it was shown that quaternary ammonium polymers adsorbed on the faces of the montmorillonite platelets, non-ionic polyacrylamides adsorbed on the faces and edges by hydrogen bonding, and anionic polyelectrolytes, carboxylates and sulfonates, did not adsorb at all on the montmorillonite [R.Y. Lochhead, C.L. McConnell-Boykin, An investigative study of polymer adsorption to smectite clay: polyelectrolytes and sodium montmorillonite, in: R. Krishnamoorti, R. Vaia (Eds.), Polymer Nanocomposites, American Chemical Society, 2002; R.Y. Lochhead, C.L. McConnell-Boykin, C. Haynes, Interaction of hydrophilic polymers with smectite clays, Polymer Materials Science and Engineering, vol. 85, American Chemical Society, 2001, p. 419]. The objective of the second part of the study was to examine model polymers in order to guide research aimed at designing coupling polymers that would cause exfoliation of the clay. Based upon the earlier study, polyvinylamine was chosen as the model on the basis that it is a simple polymer with primary amine groups and the polymer charge density could be modified by simply changing the system pH. The aim of this research was to determine the conditions under which polyvinylamine, and selected derivatives of this polymer, would penetrate the galleries of the stacked montmorillonite platelets. The knowledge gained could be applied to predict systems that would facilitate intercalation or exfoliation of sodium montmorillonite. The investigative approach of the third stage was to create a coupler from the hydrogen-bonded coacervate formed between a polyphenolic compound and polyvinylpyrrolidone, and to use this to exfoliate and couple montmorillonite nanoparticles to polycaprolactone. To achieve this, solubility parameter mapping of candidate polymeric couplers, polycaprolactone and target polyphenolic compounds was undertaken. This was used as a screening process in predicting incompatibilities and eliminating unpromising materials that were soluble in the same materials as the polycaprolactone and the polyvinylpyrrolidone. High throughput generation of Hansen-Hoy solubility diagrams coupled with simple techniques like high throughput FT-IR spectroscopy and polarized light microscopy provide a powerful tool for the evaluation of compatibility between formulation components. We were able to quickly evaluate over 110 food-contact-approved phenolic compounds, select the two promising candidates and eliminate all of the rest by evaluating their propensity for compatibility and hydrogen bonding.

Quantitation of buried contamination by use of solvents. Part 1: Solvent degradation of amine cured epoxy resins

NASA Technical Reports Server (NTRS)

Rheineck, A. E.; Heskin, R. A.; Hill, L. W.

1972-01-01

The solubility and/or swelling of cured epoxy resins was studied using the solubility parameter method. Determination of solubility parameters were found in order to select solvents for solvent-assisted degradation of cured epoxy polymers used in spacecraft. A method for improving recovery of seeded spores is suggested for assay of buried contaminants. Three commercial epoxy resins were cured using four different alkyl amines. For each resin-amine combination, three levels of amine were used, corresponding to 1/3, 2/3, and all of the amine required to react with the oxirane groups of the resin. The solubility parameters of the 36 resulting model compounds were determined in poorly and moderately hydrogen-bonded solvents. No strongly hydrogen-bonded solvents caused dissolution or swelling. The tolerance of cured resins is discussed in terms of polymer structure.

[Evaluation of inverse gas chromatography (IGC) methods to measure astragaloside solubility parameter from Buyang Huanwu decoction].

PubMed

Tang, Yu; Hu, Chao; Liao, Qiong; Liu, Wen-long; Yang, Yan-tao; He, Hong; He, Fu-yuan

2015-01-01

The solubility parameter determination of astrageloside from Buyang Huanwu decoction with inverse gas chromatography (IGC) method evaluation was investigated in this paper. Di-n-octyl phthalate Kwai alternative sample was used to carry out methodological study. The accuracy of the measured correlation coefficient was 0.992 1. Experimental precision measured by IGC experiments showed that the results were accurate and reliable. The sample was uniformly coated on the surface of an inert carrier and N2 gas was carrier gas, a variety of polar solvents such as isopropanol, toluene, acetone, chloroform, cyclohexane as probes. TCD detector temperature was 150 degrees C, gas room temperature was 120 degrees C. Similar headspace method was used whichever over 1 μL gas into the GC measurement, Retention time t(R), t(0) and all the parameters of air and probes molecules within the column were tested. Astragaloside solubility parameter was (21.02 ± 2.4) [J x cm(-3)] ½, literature value was 19.24 [J x cm(-3)] ½, and relevant coefficient was 0.984 5. IGC method is effective and accurate to measure ingredients solubility parameter.

Deprescribing for frail older people - Learning from the case of Mrs. Hansen.

PubMed

Granas, Anne Gerd; Stendal Bakken, Marit; Ruths, Sabine; Taxis, Katja

2017-07-13

Drug treatment is often an essential part in treatment and prevention of diseases in older people, but there is much concern about inappropriate medication use. This paper aims to describe the complexity of medication safety issues and clinical judgments when optimizing prescribing in older individuals. It uses the case of Mrs. Hansen, an aged nursing home resident, to illustrate the facilitators and barriers of this process. With decreasing life expectancy, medication use should shift from cure to care, focusing on symptomatic treatment to increase the patient's well-being. In Mrs. Hansen's case, the number of (potentially) dangerous medications were reduced, and non-pharmacological alternatives were considered. There were some medicines added, as underprescribing can also be a problem in older people. Deprescribing long-standing treatment can be interpreted by the patient and family as "giving up hope". More clinical evidence and practical communication tools are needed to guide deprescribing decisions, taking medical and patient-centered priorities into account. Studies evaluating such interventions should select outcome measures that are particularly relevant for frail old individuals. Copyright © 2017. Published by Elsevier Inc.

Assessment of the thermodynamic properties of poly(2,2,2-trifluoroethyl methacrylate) by inverse gas chromatography.

PubMed

Papadopoulou, Stella K; Panayiotou, Costas

2014-01-10

The thermodynamic properties of poly(2,2,2-trifluoroethyl methacrylate) (PTFEMA) were determined by the aid of the inverse gas chromatography technique (IGC), at infinite dilution. The interactions between the polymer and 15 solvents were examined in the temperature range of 120-150 °C via the estimation of the thermodynamic sorption parameters, the parameters of mixing at infinite dilution, the weight fraction activity coefficients and the Flory-Huggins interaction parameters. Additionally, the total and the partial solubility parameters of PTFEMA were estimated. The findings of this work indicate that the type and strength of the intermolecular interactions between the polymer and the solvents are strongly depended on the functional groups of the polymer and the solvents. The proton acceptor character of the polymer is responsible for the preferential solubility of PTFEMA in chloroform which acts as a proton donor solvent. The results also reveal that the polymer is insoluble in alkanes and alcohols whereas it presents good miscibility with polar solvents, especially with 2-butanone, 2-pentanone and 1,4-dioxane. Furthermore, the total and dispersive solubility parameters appear diminishing upon temperature rise, whereas the opposite behavior is noticed for the polar and hydrogen bonding solubility parameters. The latter increase with temperature, probably, due to conformational changes of the polymer on the solid support. Finally, comparison of the solubilization profiles of fluorinated methacrylic polymers studied by IGC, leads to the conclusion that PTFEMA is more soluble compared to polymers with higher fluorine content. Copyright © 2013 Elsevier B.V. All rights reserved.

Protein solubility modeling

NASA Technical Reports Server (NTRS)

Agena, S. M.; Pusey, M. L.; Bogle, I. D.

1999-01-01

A thermodynamic framework (UNIQUAC model with temperature dependent parameters) is applied to model the salt-induced protein crystallization equilibrium, i.e., protein solubility. The framework introduces a term for the solubility product describing protein transfer between the liquid and solid phase and a term for the solution behavior describing deviation from ideal solution. Protein solubility is modeled as a function of salt concentration and temperature for a four-component system consisting of a protein, pseudo solvent (water and buffer), cation, and anion (salt). Two different systems, lysozyme with sodium chloride and concanavalin A with ammonium sulfate, are investigated. Comparison of the modeled and experimental protein solubility data results in an average root mean square deviation of 5.8%, demonstrating that the model closely follows the experimental behavior. Model calculations and model parameters are reviewed to examine the model and protein crystallization process. Copyright 1999 John Wiley & Sons, Inc.

The influence of various excipients on the conversion kinetics of carbamazepine polymorphs in aqueous suspension.

PubMed

Tian, Fang; Saville, Dorothy J; Gordon, Keith C; Strachan, Clare J; Zeitler, J Axel; Sandler, Niklas; Rades, Thomas

2007-02-01

The influence of various excipients on the conversion of carbamazepine polymorphs to the dihydrate in aqueous suspension has been investigated. Ten excipients having functional groups which were potentially able to form hydrogen bonds with carbamazepine (group 1: methylcellulose, hypromellose (hydroxypropyl methylcellulose), hydroxypropylcellulose (HPC), 2-hydroxyethylcellulose (HEC), carmellose sodium (sodium carboxymethylcellulose), cellobiose; group 2: povidone (polyvinylpyrrolidone), povidone-vinyl acetate copolymer (povidone/VA) and N-methyl-2-pyrrolidone; group 3: macrogol (polyethylene glycol) and polyethylene oxide-polypropylene oxide copolymer (PEO/PPO)) were selected. Carbamazepine polymorphic forms III and I were dispersed separately into each aqueous excipient solution (0.1%, w/v) for 30 min at room temperature. The inhibition effect of each excipient was quantified using Raman spectroscopy combined with multivariate analyses. The solubility parameter of each excipient was calculated and used for categorizing excipients. Excipients in groups 1 and 2, which had both low solubility parameters (< 27.0 MPa(1/2)) and strong hydrogen bonding groups, inhibited the conversion completely. With increasing solubility parameter, the inhibition effect decreased for group 1 excipients, especially for carbamazepine form I, which had a higher specific surface area. Also, the excipients of group 3, lacking strong hydrogen bonding groups, showed poor inhibition although they had low solubility parameters (< 21.0 MPa(1/2)). This study indicated the importance of both hydrogen bonding interaction and a suitable hydrophobicity (expressed by the solubility parameter) in the inhibition of the conversion of carbamazepine to the dihydrate.

Thermodynamics of concentrated electrolyte mixtures and the prediction of mineral solubilities to high temperatures for mixtures in the system Na-K-Mg-Cl-SO 4-OH-H 2O

NASA Astrophysics Data System (ADS)

Pabalan, Roberto T.; Pitzer, Kenneth S.

1987-09-01

Mineral solubilities in binary and ternary electrolyte mixtures in the system Na-K-Mg-Cl-SO 4-OH-H 2O are calculated to high temperatures using available thermodynamic data for solids and for aqueous electrolyte solutions. Activity and osmotic coefficients are derived from the ion-interaction model of Pitzer (1973, 1979) and co-workers, the parameters of which are evaluated from experimentally determined solution properties or from solubility data in binary and ternary mixtures. Excellent to good agreement with experimental solubilities for binary and ternary mixtures indicate that the model can be successfully used to predict mineral-solution equilibria to high temperatures. Although there are currently no theoretical forms for the temperature dependencies of the various model parameters, the solubility data in ternary mixtures can be adequately represented by constant values of the mixing term θ ij and values of ψ ijk which are either constant or have a simple temperature dependence. Since no additional parameters are needed to describe the thermodynamic properties of more complex electrolyte mixtures, the calculations can be extended to equilibrium studies relevant to natural systems. Examples of predicted solubilities are given for the quaternary system NaCl-KCl-MgCl 2-H 2O.

Simulated glass-forming polymer melts: dynamic scattering functions, chain length effects, and mode-coupling theory analysis.

PubMed

Frey, S; Weysser, F; Meyer, H; Farago, J; Fuchs, M; Baschnagel, J

2015-02-01

We present molecular-dynamics simulations for a fully flexible model of polymer melts with different chain length N ranging from short oligomers (N = 4) to values near the entanglement length (N = 64). For these systems we explore the structural relaxation of the supercooled melt near the critical temperature T c of mode-coupling theory (MCT). Coherent and incoherent scattering functions are analyzed in terms of the idealized MCT. For temperatures T > T c we provide evidence for the space-time factorization property of the β relaxation and for the time-temperature superposition principle (TTSP) of the α relaxation, and we also discuss deviations from these predictions for T ≈ T c. For T larger than the smallest temperature where the TTSP holds we perform a quantitative analysis of the dynamics with the asymptotic MCT predictions for the late β regime. Within MCT a key quantity, in addition to T c, is the exponent parameter λ. For the fully flexible polymer models studied we find that λ is independent of N and has a value (λ = 0.735 ) typical of simple glass-forming liquids. On the other hand, the critical temperature increases with chain length toward an asymptotic value T c (∞) . This increase can be described by T c (∞) - T c(N) ∼ 1/N and may be interpreted in terms of the N dependence of the monomer density ρ, if we assume that the MCT glass transition is ruled by a soft-sphere-like constant coupling parameter Γ c = ρ c T c (-1/4), where ρ c is the monomer density at T c. In addition, we also estimate T c from a Hansen-Verlet-like criterion and MCT calculations based on structural input from the simulation. For our polymer model both the Hansen-Verlet criterion and the MCT calculations suggest T c to decrease with increasing chain length, in contrast to the direct analysis of the simulation data.

Polarized Radiative Transfer of a Cirrus Cloud Consisting of Randomly Oriented Hexagonal Ice Crystals: The 3 x 3 Approximation for Non-Spherical Particles

NASA Technical Reports Server (NTRS)

Stamnes, S.; Ou, S. C.; Lin, Z.; Takano, Y.; Tsay, S. C.; Liou, K.N.; Stamnes, K.

2016-01-01

The reflection and transmission of polarized light for a cirrus cloud consisting of randomly oriented hexagonal columns were calculated by two very different vector radiative transfer models. The forward peak of the phase function for the ensemble-averaged ice crystals has a value of order 6 x 10(exp 3) so a truncation procedure was used to help produce numerically efficient yet accurate results. One of these models, the Vectorized Line-by-Line Equivalent model (VLBLE), is based on the doubling- adding principle, while the other is based on a vector discrete ordinates method (VDISORT). A comparison shows that the two models provide very close although not entirely identical results, which can be explained by differences in treatment of single scattering and the representation of the scattering phase matrix. The relative differences in the reflected I and Q Stokes parameters are within 0.5 for I and within 1.5 for Q for all viewing angles. In 1971 Hansen showed that for scattering by spherical particles the 3 x 3 approximation is sufficient to produce accurate results for the reflected radiance I and the degree of polarization (DOP), and he conjectured that these results would hold also for non-spherical particles. Simulations were conducted to test Hansen's conjecture for the cirrus cloud particles considered in this study. It was found that the 3 x 3 approximation also gives accurate results for the transmitted light, and for Q and U in addition to I and DOP. For these non-spherical ice particles the 3 x 3 approximation leads to an absolute error 2 x 10(exp -6) for the reflected and transmitted I, Q and U Stokes parameters. Hence, it appears to be an excellent approximation, which significantly reduces the computational complexity and burden required for multiple scattering calculations.

Polarized radiative transfer of a cirrus cloud consisting of randomly oriented hexagonal ice crystals: The 3×3 approximation for non-spherical particles

NASA Astrophysics Data System (ADS)

Stamnes, S.; Ou, S. C.; Lin, Z.; Takano, Y.; Tsay, S. C.; Liou, K. N.; Stamnes, K.

2017-05-01

The reflection and transmission of polarized light for a cirrus cloud consisting of randomly oriented hexagonal columns were calculated by two very different vector radiative transfer models. The forward peak of the phase function for the ensemble-averaged ice crystals has a value of order 6 ×103 so a truncation procedure was used to help produce numerically efficient yet accurate results. One of these models, the Vectorized Line-by-Line Equivalent model (VLBLE), is based on the doubling-adding principle, while the other is based on a vector discrete ordinates method (VDISORT). A comparison shows that the two models provide very close although not entirely identical results, which can be explained by differences in treatment of single scattering and the representation of the scattering phase matrix. The relative differences in the reflected I and Q Stokes parameters are within 0.5% for I and within 1.5% for Q for all viewing angles. In 1971 Hansen [1] showed that for scattering by spherical particles the 3×3 approximation is sufficient to produce accurate results for the reflected radiance I and the degree of polarization (DOP), and he conjectured that these results would hold also for non-spherical particles. Simulations were conducted to test Hansen's conjecture for the cirrus cloud particles considered in this study. It was found that the 3×3 approximation also gives accurate results for the transmitted light, and for Q and U in addition to I and DOP. For these non-spherical ice particles the 3×3 approximation leads to an absolute error < 2 ×10-6 for the reflected and transmitted I, Q and U Stokes parameters. Hence, it appears to be an excellent approximation, which significantly reduces the computational complexity and burden required for multiple scattering calculations.

Use of the Flory-Huggins theory to predict the solubility of nifedipine and sulfamethoxazole in the triblock, graft copolymer Soluplus.

PubMed

Altamimi, Mohammad A; Neau, Steven H

2016-01-01

Drug dispersed in a polymer can improve bioavailability; dispersed amorphous drug undergoes recrystallization. Solid solutions eliminate amorphous regions, but require a measure of the solubility. Use the Flory-Huggins Theory to predict crystalline drugs solubility in the triblock, graft copolymer Soluplus® to provide a solid solution. Physical mixtures of the two drugs with similar melting points but different glass forming ability, sulfamethoxazole and nifedipine, were prepared with Soluplus® using a quick technique. Drug melting point depression (MPD) was measured using differential scanning calorimetry. The Flory-Huggins Theory allowed: (1) interaction parameter, χ, calculation using MPD data to provide a measure of drug-polymer interaction strength and (2) estimation of the free energy of mixing. A phase diagram was constructed with the MPD data and glass transition temperature (Tg) curves. The interaction parameters with Soluplus® and the free energy of mixing were estimated. Drug solubility was calculated by the intersection of solubility equations and that of MPD and Tg curves in the phase diagram. Negative interaction parameters indicated strong drug-polymer interactions. The phase diagram and solubility equations provided comparable solubility estimates for each drug in Soluplus®. Results using the onset of melting rather than the end of melting support the use of the onset of melting. The Flory-Huggins Theory indicates that Soluplus® interacts effectively with each drug, making solid solution formation feasible. The predicted solubility of the drugs in Soluplus® compared favorably across the methods and supports the use of the onset of melting.

Use of the Flory-Huggins theory to predict the solubility of nifedipine and sulfamethoxazole in the triblock, graft copolymer Soluplus.

PubMed

Altamimi, Mohammad A; Neau, Steven H

2016-03-01

Drug dispersed in a polymer can improve bioavailability; dispersed amorphous drug undergoes recrystallization. Solid solutions eliminate amorphous regions, but require a measure of the solubility. Use the Flory-Huggins Theory to predict crystalline drugs solubility in the triblock, graft copolymer Soluplus® to provide a solid solution. Physical mixtures of the two drugs with similar melting points but different glass forming ability, sulfamethoxazole and nifedipine, were prepared with Soluplus® using a quick technique. Drug melting point depression (MPD) was measured using differential scanning calorimetry. The Flory-Huggins Theory allowed: (1) interaction parameter, χ, calculation using MPD data to provide a measure of drug-polymer interaction strength and (2) estimation of the free energy of mixing. A phase diagram was constructed with the MPD data and glass transition temperature (T g ) curves. The interaction parameters with Soluplus® and the free energy of mixing were estimated. Drug solubility was calculated by the intersection of solubility equations and that of MPD and T g curves in the phase diagram. Negative interaction parameters indicated strong drug-polymer interactions. The phase diagram and solubility equations provided comparable solubility estimates for each drug in Soluplus®. Results using the onset of melting rather than the end of melting support the use of the onset of melting. The Flory-Huggins Theory indicates that Soluplus® interacts effectively with each drug, making solid solution formation feasible. The predicted solubility of the drugs in Soluplus® compared favorably across the methods and supports the use of the onset of melting.

Coal desulfurization

NASA Technical Reports Server (NTRS)

Corcoran, William H. (Inventor); Vasilakos, Nicholas P. (Inventor); Lawson, Daniel D. (Inventor)

1982-01-01

A method for enhancing solubilizing mass transport of reactive agents into and out of carbonaceous materials, such as coal. Solubility parameters of mass transfer and solvent media are matched to individual peaks in the solubility parameter spectrum of coals to enhance swelling and/or dissolution. Methanol containing reactive agent carriers are found particularly effective for removing organic sulfur from coals by chlorinolysis.

EFFECTS OF INHALATION OF SOLUBLE METALLIC CONSTITUENTS OF PARTICULATE MATTER ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS IN GUINEA PIGS

EPA Science Inventory

EFFECTS OF INHALATION OF SOLUBLE METALLIC CONSTITUENTS OF PARTICULATE MATTER ON CARDIOPULMONARY, THERMOREGULATORY, AND BIOCHEMICAL PARAMETERS IN GUINEA PIGS. JP Nolan1, LB Wichers2, J Stanek3, UP Kodavanti1, MCJ Schladweiler1, PA Evansky1, ER Lappi1, DL Costa1, and WP Watkinson1...

A Thermodynamic Approach for Modeling H2O-CO2 Solubility in Alkali-rich Mafic Magmas at Mid-crustal Pressures

NASA Astrophysics Data System (ADS)

Allison, C. M.; Roggensack, K.; Clarke, A. B.

2017-12-01

Volatile solubility in magmas is dependent on several factors, including composition and pressure. Mafic (basaltic) magmas with high concentrations of alkali elements (Na and K) are capable of dissolving larger quantities of H2O and CO2 than low-alkali basalt. The exsolution of abundant gases dissolved in alkali-rich mafic magmas can contribute to large explosive eruptions. Existing volatile solubility models for alkali-rich mafic magmas are well calibrated below 200 MPa, but at greater pressures the experimental data is sparse. To allow for accurate interpretation of mafic magmatic systems at higher pressures, we conducted a set of mixed H2O-CO2 volatile solubility experiments between 400 and 600 MPa at 1200 °C in six mafic compositions with variable alkali contents. Compositions include magmas from volcanoes in Italy, Antarctica, and Arizona. Results from our experiments indicate that existing volatile solubility models for alkali-rich mafic magmas, if extrapolated beyond their calibrated range, over-predict CO2 solubility at mid-crustal pressures. Physically, these results suggest that volatile exsolution can occur at deeper levels than what can be resolved from the lower-pressure experimental data. Existing thermodynamic models used to calculate volatile solubility at different pressures require two experimentally derived parameters. These parameters represent the partial molar volume of the condensed volatile species in the melt and its equilibrium constant, both calculated at a standard temperature and pressure. We derived these parameters for each studied composition and the corresponding thermodynamic model shows good agreement with the CO2 solubility data of the experiments. A general alkali basalt solubility model was also constructed by establishing a relationship between magma composition and the thermodynamic parameters. We utilize cation fractions from our six compositions along with four compositions from the experimental literature in a linear regression to generate this compositional relationship. Our revised general model provides a new framework to interpret volcanic data, yielding greater depths for melt inclusion entrapment than previously calculated using other models, and it can be applied to mafic magma compositions for which no experimental data is available.

Benzoic Acid and Chlorobenzoic Acids: Thermodynamic Study of the Pure Compounds and Binary Mixtures With Water.

PubMed

Reschke, Thomas; Zherikova, Kseniya V; Verevkin, Sergey P; Held, Christoph

2016-03-01

Benzoic acid is a model compound for drug substances in pharmaceutical research. Process design requires information about thermodynamic phase behavior of benzoic acid and its mixtures with water and organic solvents. This work addresses phase equilibria that determine stability and solubility. In this work, Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) was used to model the phase behavior of aqueous and organic solutions containing benzoic acid and chlorobenzoic acids. Absolute vapor pressures of benzoic acid and 2-, 3-, and 4-chlorobenzoic acid from literature and from our own measurements were used to determine pure-component PC-SAFT parameters. Two binary interaction parameters between water and/or benzoic acid were used to model vapor-liquid and liquid-liquid equilibria of water and/or benzoic acid between 280 and 413 K. The PC-SAFT parameters and 1 binary interaction parameter were used to model aqueous solubility of the chlorobenzoic acids. Additionally, solubility of benzoic acid in organic solvents was predicted without using binary parameters. All results showed that pure-component parameters for benzoic acid and for the chlorobenzoic acids allowed for satisfying modeling phase equilibria. The modeling approach established in this work is a further step to screen solubility and to predict the whole phase region of mixtures containing pharmaceuticals. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Clinical and Biological Predictors of Plasma Levels of Soluble RAGE in Critically Ill Patients: Secondary Analysis of a Prospective Multicenter Observational Study.

PubMed

Pranal, Thibaut; Pereira, Bruno; Berthelin, Pauline; Roszyk, Laurence; Godet, Thomas; Chabanne, Russell; Eisenmann, Nathanael; Lautrette, Alexandre; Belville, Corinne; Blondonnet, Raiko; Cayot, Sophie; Gillart, Thierry; Skrzypczak, Yvan; Souweine, Bertrand; Bouvier, Damien; Blanchon, Loic; Sapin, Vincent; Constantin, Jean-Michel; Jabaudon, Matthieu

2018-01-01

Although soluble forms of the receptor for advanced glycation end products (RAGE) have been recently proposed as biomarkers in multiple acute or chronic diseases, few studies evaluated the influence of usual clinical and biological parameters, or of patient characteristics and comorbidities, on circulating levels of soluble RAGE in the intensive care unit (ICU) setting. To determine, among clinical and biological parameters that are usually recorded upon ICU admission, which variables, if any, could be associated with plasma levels of soluble RAGE. Data for this ancillary study were prospectively obtained from adult patients with at least one ARDS risk factor upon ICU admission enrolled in a large multicenter observational study. At ICU admission, plasma levels of total soluble RAGE (sRAGE) and endogenous secretory (es)RAGE were measured by duplicate ELISA and baseline patient characteristics, comorbidities, and usual clinical and biological indices were recorded. After univariate analyses, significant variables were used in multivariate, multidimensional analyses. 294 patients were included in this ancillary study, among whom 62% were admitted for medical reasons, including septic shock (11%), coma (11%), and pneumonia (6%). Although some variables were associated with plasma levels of RAGE soluble forms in univariate analysis, multidimensional analyses showed no significant association between admission parameters and baseline plasma sRAGE or esRAGE. We found no obvious association between circulating levels of soluble RAGE and clinical and biological indices that are usually recorded upon ICU admission. This trial is registered with NCT02070536.

[Determination of solubility parameters of high density polyethylene by inverse gas chromatography].

PubMed

Wang, Qiang; Chen, Yali; Liu, Ruiting; Shi, Yuge; Zhang, Zhengfang; Tang, Jun

2011-11-01

Inverse gas chromatographic (IGC) technology was used to determine the solubility parameters of high density polyethylene (HDPE) at the absolute temperatures from 303.15 to 343.15 K. Six solvents were applied as test probes including hexane (n-C6), heptane (n-C7), octane (n-C8), nonane (n-C9), chloroform (CHCl3) and ethyl acetate (EtAc). Some thermodynamic parameters were obtained by IGC data analysis such as the specific retention volumes of the solvents (V(0)(g)), the molar enthalpy of sorption (delta H(S)(1)), the partial molar enthalpy of mixing at infinite dilution (delta H(1)(infinity)), the molar enthalpy of vaporization (delta H(v)), the activity coefficients at infinite dilution (omega (1)(infinity)), and Flow-Huggins interaction parameters (X(1,2)(infinity)) between HDPE and probe solvents. The results showed that the above six probes are poor solvents for HDPE. The solubility parameter of HDPE at room temperature (298.15 K) was also derived as 19.00 (J/cm3)(0.5).

Structure modification and functionality of whey proteins: quantitative structure-activity relationship approach.

PubMed

Nakai, S; Li-Chan, E

1985-10-01

According to the original idea of quantitative structure-activity relationship, electric, hydrophobic, and structural parameters should be taken into consideration for elucidating functionality. Changes in these parameters are reflected in the property of protein solubility upon modification of whey proteins by heating. Although solubility is itself a functional property, it has been utilized to explain other functionalities of proteins. However, better correlations were obtained when hydrophobic parameters of the proteins were used in conjunction with solubility. Various treatments reported in the literature were applied to whey protein concentrate in an attempt to obtain whipping and gelling properties similar to those of egg white. Mapping simplex optimization was used to search for the best results. Improvement in whipping properties by pepsin hydrolysis may have been due to higher protein solubility, and good gelling properties resulting from polyphosphate treatment may have been due to an increase in exposable hydrophobicity. However, the results of angel food cake making were still unsatisfactory.

Study of linear optical parameters of sodium sulphide nano-particles added ADP crystals

NASA Astrophysics Data System (ADS)

Kochuparampil, A. P.; Joshi, J. H.; Dixit, K. P.; Jethva, H. O.; Joshi, M. J.

2017-05-01

Ammonium Dihydrogen Phosphate (ADP) is one of the nonlinear optical crystals. It is having various applications like optical mixing, electro-optical modulator, harmonic generators, etc. Chalcogenide compounds are poorly soluble in water and difficult to add in the water soluble ADP crystals. The solubility of Chalcogenide compounds can be increased by synthesizing the nano-structured samples with suitable capping agent. In the present study sodium sulphide was added in to ADP to modify its linear optical parameters. Sodium sulphide nano particles were synthesized by co-precipitation technique using Ethylene diamine as capping agent followed by microwave irradiation. The powder XRD confirmed the nano-structured nature of sodium sulphide nano particles. The solubility of nanoparticles of sodium sulphide increased significantly in water compared to the bulk. Pure and Na2S added ADP crystals were grown by slow solvent evaporation method at room temperature. The presence of sodium in ADP was confirmed by AAS. The UV-Vis spectra were recorded for all crystals. Various optical parameters like, transmittance, energy band gap, extinction coefficient, refractive index, optical conductivity, etc. were evaluated. The electronic polarizibility of pure and doped crystals calculated from energy band gap. The effect of doping concentration was found on various parameters.

Decision trees to characterise the roles of permeability and solubility on the prediction of oral absorption.

PubMed

Newby, Danielle; Freitas, Alex A; Ghafourian, Taravat

2015-01-27

Oral absorption of compounds depends on many physiological, physiochemical and formulation factors. Two important properties that govern oral absorption are in vitro permeability and solubility, which are commonly used as indicators of human intestinal absorption. Despite this, the nature and exact characteristics of the relationship between these parameters are not well understood. In this study a large dataset of human intestinal absorption was collated along with in vitro permeability, aqueous solubility, melting point, and maximum dose for the same compounds. The dataset allowed a permeability threshold to be established objectively to predict high or low intestinal absorption. Using this permeability threshold, classification decision trees incorporating a solubility-related parameter such as experimental or predicted solubility, or the melting point based absorption potential (MPbAP), along with structural molecular descriptors were developed and validated to predict oral absorption class. The decision trees were able to determine the individual roles of permeability and solubility in oral absorption process. Poorly permeable compounds with high solubility show low intestinal absorption, whereas poorly water soluble compounds with high or low permeability may have high intestinal absorption provided that they have certain molecular characteristics such as a small polar surface or specific topology. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Freezing lines of colloidal Yukawa spheres. II. Local structure and characteristic lengths

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

Gapinski, Jacek, E-mail: gapinski@amu.edu.pl; Patkowski, Adam; NanoBioMedical Center, A. Mickiewicz University, Umultowska 85, 61-614 Poznań

Using the Rogers-Young (RY) integral equation scheme for the static pair correlation functions combined with the liquid-phase Hansen-Verlet freezing rule, we study the generic behavior of the radial distribution function and static structure factor of monodisperse charge-stabilized suspensions with Yukawa-type repulsive particle interactions at freezing. In a related article, labeled Paper I [J. Gapinski, G. Nägele, and A. Patkowski, J. Chem. Phys. 136, 024507 (2012)], this hybrid method was used to determine two-parameter freezing lines for experimentally controllable parameters, characteristic of suspensions of charged silica spheres in dimethylformamide. A universal scaling of the RY radial distribution function maximum is shownmore » to apply to the liquid-bcc and liquid-fcc segments of the universal freezing line. A thorough analysis is made of the behavior of characteristic distances and wavenumbers, next-neighbor particle coordination numbers, osmotic compressibility factor, and the Ravaché-Mountain-Streett minimum-maximum radial distribution function ratio.« less

Clinical and Biological Predictors of Plasma Levels of Soluble RAGE in Critically Ill Patients: Secondary Analysis of a Prospective Multicenter Observational Study

PubMed Central

Pranal, Thibaut; Pereira, Bruno; Berthelin, Pauline; Roszyk, Laurence; Chabanne, Russell; Eisenmann, Nathanael; Lautrette, Alexandre; Belville, Corinne; Blondonnet, Raiko; Gillart, Thierry; Skrzypczak, Yvan; Souweine, Bertrand; Bouvier, Damien; Constantin, Jean-Michel

2018-01-01

Rationale Although soluble forms of the receptor for advanced glycation end products (RAGE) have been recently proposed as biomarkers in multiple acute or chronic diseases, few studies evaluated the influence of usual clinical and biological parameters, or of patient characteristics and comorbidities, on circulating levels of soluble RAGE in the intensive care unit (ICU) setting. Objectives To determine, among clinical and biological parameters that are usually recorded upon ICU admission, which variables, if any, could be associated with plasma levels of soluble RAGE. Methods Data for this ancillary study were prospectively obtained from adult patients with at least one ARDS risk factor upon ICU admission enrolled in a large multicenter observational study. At ICU admission, plasma levels of total soluble RAGE (sRAGE) and endogenous secretory (es)RAGE were measured by duplicate ELISA and baseline patient characteristics, comorbidities, and usual clinical and biological indices were recorded. After univariate analyses, significant variables were used in multivariate, multidimensional analyses. Measurements and Main Results 294 patients were included in this ancillary study, among whom 62% were admitted for medical reasons, including septic shock (11%), coma (11%), and pneumonia (6%). Although some variables were associated with plasma levels of RAGE soluble forms in univariate analysis, multidimensional analyses showed no significant association between admission parameters and baseline plasma sRAGE or esRAGE. Conclusions We found no obvious association between circulating levels of soluble RAGE and clinical and biological indices that are usually recorded upon ICU admission. This trial is registered with NCT02070536. PMID:29861796

Characterization of Haemophilus ducreyi cdtA, cdtB, and cdtC Mutants in In Vitro and In Vivo Systems

PubMed Central

Lewis, David A.; Stevens, Marla K.; Latimer, Jo L.; Ward, Christine K.; Deng, Kaiping; Blick, Robert; Lumbley, Sheryl R.; Ison, Catherine A.; Hansen, Eric J.

2001-01-01

Haemophilus ducreyi expresses a soluble cytolethal distending toxin (CDT) that is encoded by the cdtABC gene cluster and can be detected in culture supernatant fluid by its ability to kill HeLa cells. The cdtA, cdtB, and cdtC genes of H. ducreyi were cloned independently into plasmid vectors, and their encoded proteins expressed singly or in various combinations in an Escherichia coli background. All three gene products had to be expressed in order for E. coli-derived culture supernatant fluids to demonstrate cytotoxicity for HeLa cells. Isogenic H. ducreyi cdtA and cdtB mutants were constructed and used in combination with the wild-type parent strain and a previously described H. ducreyi cdtC mutant (M. K. Stevens, J. L. Latimer, S. R. Lumbley, C. K. Ward, L. D. Cope, T. Lagergard, and E. J. Hansen, Infect. Immun. 67:3900–3908, 1999) to determine the relative contributions of the CdtA, CdtB, and CdtC proteins to CDT activity. Expression of CdtA, CdtB, and CdtC appeared necessary for H. ducreyi-derived culture supernatant fluid to exhibit cytotoxicity for HeLa cells. Whole-cell sonicates and periplasmic extracts from the cdtB and cdtC mutants had no effect on HeLa cells, whereas these same fractions from a cdtA mutant had a very modest cytotoxic effect on these same human cells. CdtA appeared to be primarily associated with the H. ducreyi cell envelope, whereas both CdtB and CdtC were present primarily in the soluble fraction from sonicated cells. Both the cdtA mutant and the cdtB mutant were found to be fully virulent in the temperature-dependent rabbit model for experimental chancroid. PMID:11500438

Predicting the equilibrium solubility of solid polycyclic aromatic hydrocarbons and dibenzothiophene using a combination of MOSCED plus molecular simulation or electronic structure calculations

NASA Astrophysics Data System (ADS)

Phifer, Jeremy R.; Cox, Courtney E.; da Silva, Larissa Ferreira; Nogueira, Gabriel Gonçalves; Barbosa, Ana Karolyne Pereira; Ley, Ryan T.; Bozada, Samantha M.; O'Loughlin, Elizabeth J.; Paluch, Andrew S.

2017-06-01

Methods to predict the equilibrium solubility of non-electrolyte solids are important for the design of novel separation processes. Here we demonstrate how conventional molecular simulation free energy calculations or electronic structure calculations in a continuum solvent, here SMD or SM8, can be used to predict parameters for the MOdified Separation of Cohesive Energy Density (MOSCED) method. The method is applied to the solutes naphthalene, anthracene, phenanthrene, pyrene and dibenzothiophene, compounds of interested to the petroleum industry and for environmental remediation. Adopting the melting point temperature and enthalpy of fusion of these compounds from experiment, we are able to predict equilibrium solubilities. Comparing to a total of 422 non-aqueous and 193 aqueous experimental solubilities, we find the proposed method is able to well correlate the data. The use of MOSCED is additionally advantageous as it is a solubility parameter-based method useful for intuitive solvent selection and formulation.

Modeling CO{sub 2} and H{sub 2}S solubility in MDEA and DEA: Design implications

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

Rochelle, G.T.; Posey, M.

1996-12-31

The solubility of H{sub 2}S and CO{sub 2} in aqueous alkanolamines affects solution capacity and the required circulation rate for acid gas absorption. These thermodynamics also determine the relationship of steam rate and the lean loading of the solution which in turn sets the leak of acid gas from the top of the absorber. Finally, the mechanisms of mass transfer and the role of kinetics, especially in stripping, depend on the vapor/liquid equilibria. Published measurements of CO{sub 2} and H{sub 2}S solubility in methyldiethanolamine (MDEA) and diethanolamine (DEA) are not in general agreement, especially at low loading of acid gas.more » The available sets of solubility data have been regressed with the AspenPlus electrolyte/NRTL model. All of the parameters and constants that make up this model have been carefully evaluated. Independent thermodynamic data such as freezing point and heat of mixing have been included in the regression to strengthen the estimates of model parameters. The parameters for each set of solubility data have been evaluated in an attempt to determine which set is correct. Each evaluated model has been used to calculate the acid gas capacity and minimum stripping steam rate for several industrial cases of acid gas absorption/stripping.« less

Evaluation of solubility in simulated lung fluid of metals present in the slag from a metallurgical industry to produce metallic zinc.

PubMed

Lima, Rosilda M G; Carneiro, Luana G; Afonso, Júlio C; Cunha, Kenya M D

2013-01-01

The objective of this study was to determine the solubility parameters (rapid and slow dissolution rates, rapid and slow dissolution fractions) for nickel, cadmium, zinc and manganese compounds present in a pile of slag accumulated under exposure to weathering. This slag was generated by a metallurgical industry that produced zinc and zinc alloys from hemimorphite (Zn(4)(OH)(2)Si(2)O(7).H(2)O) and willemite (Zn(2)SiO(4)) minerals. A static dissolution test in vitro was used to determine the solubility parameters and Gamble's solution was used as the simulated lung fluid (SLF), on a time basis ranging from 10 min to 1 year. The metal concentrations in the slag samples and in the SLF were determined using Particle Induced X-rays Emission (PIXE). There are significant differences in terms of solubility parameters among the metals. The results indicated that the zinc, nickel, cadmium and manganese compounds present in the slag were moderately soluble in the SLF. The rapid dissolution fractions of these metals are associated with their sulfates. In conclusion, this study confirms the harmful effects on the neighboring population of the airborne particles containing these metals that came from the slag.

The Role of Solvent-Solute Interactions on The Behavior of Low Molecular Mass Organo-Gelators

NASA Astrophysics Data System (ADS)

Cavicchi, Kevin; Feng, Li

2012-02-01

Low molecular mass organo-gelators (LMOGs) are a class of small molecules that can self-assemble in organic solvents to form three-dimensional fibrillar networks. This has a profound effect on the viscoelastic properties of the solution causing physical gelation. These gels have uses in a range of industries including cosmetics, foodstuffs, plastics, petroleum and pharmaceuticals. A fundamental question in this field is: What makes a good LMOG? This talk will discuss the relationships between the viscoelastic properties and thermodynamic phase behavior of LMOG/solvent solutions. The regular solution model was used to fit the liquidus line and sol/gel transition temperature vs. concentration in different solvents to determine LMOG-solvent interaction parameters (χ = A/T). This parameter A was found to scale with the solubility parameter of the solvent, especially for non-polar solvents. This demonstrates that gelation is strongly linked to LMOG solubility and indicates that the bulk thermodynamic parameters of the LMOG (solubility parameter and melting temperature) are useful to predict the solution behavior of LMOGs.

Update in pediatrics: focus on fat-soluble vitamins.

PubMed

Sathe, Meghana N; Patel, Ashish S

2010-08-01

This article provides an update on fat-soluble vitamins (A, D, E, and K) in the healthy pediatric population and in children with chronic disease states that commonly cause deficiencies, specifically cystic fibrosis and cholestatic liver disease. For each fat-soluble vitamin, the biological function, nutrition availability, absorption, deficiency, toxic states, and monitoring parameters are defined.

Solubility and surface thermodynamics of conducting polymers by inverse gas chromatography. III: polypyrrole chloride.

PubMed

Duaij, Omar K; Alghamdi, Ali; Al-Saigh, Zeki Y

2013-05-24

Inverse gas chromatography, IGC, was applied to characterize conducting polypyrrole chloride (PPyCl) using twenty three solvents. IGC is able to reveal the change in the morphology, the strength of solvent-PPyCl interactions, thermodynamics parameters (χ12, Ω1(∞)), solvent and polymer solubility parameters, and molar heats of sorption, mixing and evaporation (ΔH1(s), ΔH1(∞), ΔH1(v)). The following solvents showed stronger interactions than others; yet, none of these solvents are good solvents for PPyCl: dodecane among the alkane family, tetrahydrofuran and methyl ethyl ketone among the oxy and keto group, dichloromethane among the chlorinated group up to 120°C and chloroform at 180°C, and toluene among the cyclic and aromatic group. Overall, the groups showed higher affinities to PPyCl are: acetates, oxy and cyclic, and chlorinated groups. Comprehensive solvents and PPyCl solubility parameters are obtained. The latter showed that PPyCl is not soluble in any solvent used. Copyright © 2013 Elsevier B.V. All rights reserved.

Dependence of the surface roughness of MAPLE-deposited films on the solvent parameters

NASA Astrophysics Data System (ADS)

Caricato, A. P.; Leggieri, G.; Martino, M.; Vantaggiato, A.; Valerini, D.; Cretì, A.; Lomascolo, M.; Manera, M. G.; Rella, R.; Anni, M.

2010-12-01

Matrix-assisted pulsed laser evaporation (MAPLE) was used to deposit layers of poly(9,9-dioctylfluorene) (PFO) to study the relation between the solvent properties (laser light absorption, boiling temperature and solubility parameters) and the morphology of the deposited films. To this end, the polymer was diluted (0.5 wt%) in tetrahydrofuran—THF, toluene and toluene/hexane mixtures. The thickness of the films was equal to 70±20 nm. The morphology and uniformity of the films was investigated by Atomic Force Microscopy and by the photoluminescence emission properties of the polymer films, respectively. It is shown that, although the solubility parameters of the solvents are important in controlling the film roughness and morphology, the optical absorption properties and boiling temperature play a very important role, too. In fact, for matrices characterized by the same total solubility parameter, lower roughness values are obtained for films prepared using solvents with lower penetration depth of the laser radiation and higher boiling temperatures.

The effect of relative solubility on crystal purity

NASA Astrophysics Data System (ADS)

Givand, Jeffrey Christopher

This study establishes the relationship between impurity incorporation in a crystal by lattice substitution and the solubility of that impurity in solution. The model system studied was L-isoleucine crystals contaminated by the isomorphic impurity L-leucine. Upon crystallization from aqueous solution by cooling, leucine is concentrated in the isoleucine unit cell through lattice substitution mechanisms. Attempts to reduce the degree of leucine incorporation via adjustments of the rate at which supersaturation is generated yielded marginal success. This work demonstrates that incorporation of leucine in the crystal can be considerably suppressed by reducing the solubility of product relative to the solubility of impurity. Changes to the relative solubility of the impurity were accomplished by the addition of various electrolytes and organic co-solvents to the aqueous amino acid solutions. The solubilities of the two amino acids were measured and compared to their solubilities in pure water. Changes in the ratio of pure-component solubilities were directly related to changes in crystal purity. This thermodynamic quantity of relative solubility was shown to be a key factor in determining impurity uptake by lattice substitution. In addition to the experimental observations, a fundamental thermodynamic link between relative solubility and crystal purity is established through this research. First, the amino acid solubility data as a function of temperature in all solvent mixtures were accurately correlated using a thermodynamic model. The parameters from this model were then adapted to a novel solid-solution thermodynamic model to express the crystal purity in terms of equilibrium solution impurity concentration. After the determination of one system specific parameter, the model is able to predict the crystal purity in a new solvent in which the pure-component solubilities are known. The ability of an electrolyte or co-solvent to improve crystal purity from a given level can now be determined based on existing solubility and purity measurements and solubilities of the product and impurity in the new solvent mixture.

Inferring the anthropogenic contribution to local temperature extremes

DOE PAGES

Stone, Dáithí A.; Paciorek, Christopher J.; Prabhat, .; ...

2013-03-19

Here, in PNAS, Hansen et al. document an observed planet-wide increase in the frequency of extremely hot months and a decrease in the frequency of extremely cold months, consistent with earlier studies. This analysis is achieved through aggregation of gridded monthly temperature measurements from all over the planet. Such aggregation is advantageous in achieving statistical sampling power; however, it sacrifices regional specificity. Lastly, in that light, we find the conclusion of Hansen et al. that “the extreme summer climate anomalies in Texas in 2011, in Moscow in 2010, and in France in 2003 almost certainly would not have occurred inmore » the absence of global warming” to be unsubstantiated by their analysis.« less

Inferring the anthropogenic contribution to local temperature extremes

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

Stone, Dáithí A.; Paciorek, Christopher J.; Prabhat, .

Here, in PNAS, Hansen et al. document an observed planet-wide increase in the frequency of extremely hot months and a decrease in the frequency of extremely cold months, consistent with earlier studies. This analysis is achieved through aggregation of gridded monthly temperature measurements from all over the planet. Such aggregation is advantageous in achieving statistical sampling power; however, it sacrifices regional specificity. Lastly, in that light, we find the conclusion of Hansen et al. that “the extreme summer climate anomalies in Texas in 2011, in Moscow in 2010, and in France in 2003 almost certainly would not have occurred inmore » the absence of global warming” to be unsubstantiated by their analysis.« less

Validation of Hansen-Roach library for highly enriched uranium metal systems

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

Wenz, T.R.; Busch, R.D.

The Hansen-Roach 16-group cross-section library has been validated for use in pure uranium metal systems by modeling the Godiva critical assembly using the neutronics transport theory code ONEDANT to perform effective multiplication factor (k{sub eff}) calculations. The cross-section library used contains data for 118 isotopes (34 unique elements), including the revised cross sections for {sup 235}U and {sup 238}U. The Godiva critical assembly is a 17.4-cm sphere composed of 93.7 wt% {sup 235}U, 1.0 wt% {sup 234}U, and 5.3 wt% {sup 238}U with an effective homogeneous density of 18.7 g/cm{sup 3}.

A green analytical chemistry approach for lipid extraction: computation methods in the selection of green solvents as alternative to hexane.

PubMed

Cascant, Mari Merce; Breil, Cassandra; Garrigues, Salvador; de la Guardia, Miguel; Fabiano-Tixier, Anne Silvie; Chemat, Farid

2017-05-01

There is a great interest in finding alternatives and green solvents in extraction processes to replace petroleum based solvents. In order to investigate these possibilities, computational methods, as Hansen solubility parameters (HSP) and conductor-like screening model for real solvent (COSMO-RS), were used in this work to predict the solvation power of a series of solvents in salmon fish lipids. Additionally, experimental studies were used to evaluate the performance in lipids extraction using 2-methyltetrahydrofurane, cyclopentyl methyl ether, dimethyl carbonate, isopropanol, ethanol, ethyl acetate, p-cymene and d-limonene compared with hexane. Lipid classes of extracts were obtained by using high performance thin-layer chromatography (HPTLC), whereas gas chromatography with a flame ionization detector (GC/FID) technique was employed to obtain fatty acid profiles. Some differences between theoretical and experimental results were observed, especially regarding the behavior of p-cymene and d-limonene, which separate from the predicted capability. Results obtained from HPTLC indicated that p-cymene and d-limonene extract triglycerides (TAGs) and diglycerides (DAGs) at levels of 73 and 19%, respectively, whereas the other studied extracts contain between 75 and 76% of TAGs and between 16 and 17% of DAGs. Fatty acid profiles, obtained by using GC-FID, indicated that saturated fatty acids (SFAs) between 19.5 and 19.9% of extracted oil, monounsaturated fatty acids (MUFAs) in the range between 43.5 and 44.9%, and PUFAs between 31.2 and 34.6% were extracted. p-Cymene and limonene extracts contained lower percentages than the other studied solvents of some PUFAs due probably to the fact that these unsaturated fatty acids are more susceptible to oxidative degradation than MUFAs. Ethyl acetate has been found to be the best alternative solvent to hexane for the extraction of salmon oil lipids. Graphical Abstract ᅟ.

Pyrenyl-linker-glucono gelators. Correlations of gel properties with gelator structures and characterization of solvent effects.

PubMed

Yan, Ni; Xu, Zhiyan; Diehn, Kevin K; Raghavan, Srinivasa R; Fang, Yu; Weiss, Richard G

2013-01-15

A series of glucono-appended 1-pyrenesulfonyl derivatives containing α,ω-diaminoalkane spacers (Pn, where n, the number of methylene units separating the amino groups, is 2, 3, 4, 6, 7, and 8) have been prepared. Careful analyses of correlations between the structures of these molecules and their gels have provided important insights into the factors responsible for one-dimensional aggregation of small molecules containing both lipophilic and hydrophilic parts. The gelation behavior has been examined in 30 liquids of diverse structure and polarity, and the properties of their gels and the gelation mechanisms have been investigated using a variety of techniques. Possible reasons are discussed regarding why the Pn are better gelators than the corresponding naphthyl analogues (Nn) which had been investigated previously. P2 and P3 are ambidextrous gelators (i.e., they gelate both water and some organic liquids), and P4-P8 gelate some organic liquids which are protic and aprotic, but not water. In at least one of the liquids examined, P3, P4, P6, P7, and P8 form gels at less than 1 w/v % concentrations, and some of the gels in 1-decanol are thixotropic. Analyses of the gelation abilities using Hansen solubility parameters yield both qualitative and quantitative insights into the role of liquid-gelator interactions. For example, the critical gelation concentrations increase generally with increasing polar and hydrogen bonding interactions between the gelators and their liquid components. As revealed by FT-IR, (1)H NMR, UV-vis, and fluorescence spectra, hydrogen-bonding between glucono units and π-π stacking between pyrenyl groups are important in the formation and maintenance of the gel networks. The results from this study, especially those relating the aggregation modes and liquid properties, offer insights for the design of new surfactant-containing low-molecular-mass gelators with predefined gelating abilities.

Reactivity of vinyl ethers and vinyl ribosides in UV-initiated free radical copolymerization with acceptor monomers.

PubMed

Pichavant, Loic; Guillermain, Céline; Coqueret, Xavier

2010-09-13

The reactivity of various vinyl ethers and vinyloxy derivatives of ribose in the presence of diethyl fumarate or diethyl maleate was investigated for evaluating the potential of donor-acceptor-type copolymerization applied to unsaturated monomers derived from renewable feedstock. The photochemically induced polymerization of model monomer blends in the bulk state was monitored by infrared spectroscopy. The method allowed us to examine the influence of monomer pair structure on the kinetic profiles. The simultaneous consumption of both monomers was observed, supporting an alternating copolymerization mechanism. A lower reactivity of the blends containing maleates compared with fumarates was confirmed. The obtained kinetic data revealed a general correlation between the initial polymerization rate and the Hansen parameter δ(H) associated with the H-bonding aptitude of the donor monomer.

THERAPIST PERCEPTIONS OF INTIMATE PARTNER VIOLENCE: A REPLICATION OF HARWAY AND HANSEN2019;S STUDY AFTER MORE THAN A DECADE

PubMed Central

Dudley, Desreen Raphael; McCloskey, Kathy; Kustron, Debora A.

2014-01-01

More than a decade ago, Hansen, Harway, and Cervantes (1991) and Harway and Hansen (1993) conducted a research study examining mental health providers’ ability to accurately perceive violence within couples presenting for therapy and to intervene in a manner in which to reduce the risk of danger to couples. The results were alarming, with 40% of therapists sampled failing to perceive intimate partner violence (IPV) and virtually no therapists intervening to reduce the risk of lethality. Harway and colleagues questioned how well-trained and informed therapists were in assessing IPV. The present study replicates Harway and colleagues’ study with the expectation that, over a decade later, therapists are better prepared to accurately identify IPV issues and intervene effectively to reduce the risk of lethality. Reproducing the two main procedures used in the original study, 111 psychologists, clinical social workers, and marriage and family therapists were asked to respond to a survey. Results show that therapists have indeed improved their ability to identify IPV issues. Twenty percent of therapists predicted an increase in conflict, compared to 4% in the original sample. However, almost no therapists accurately predicted lethality in either study. Implications concerning IPV training for therapists are discussed. PMID:24729677

Estimation of the solubility parameters of model plant surfaces and agrochemicals: a valuable tool for understanding plant surface interactions

PubMed Central

2012-01-01

Background Most aerial plant parts are covered with a hydrophobic lipid-rich cuticle, which is the interface between the plant organs and the surrounding environment. Plant surfaces may have a high degree of hydrophobicity because of the combined effects of surface chemistry and roughness. The physical and chemical complexity of the plant cuticle limits the development of models that explain its internal structure and interactions with surface-applied agrochemicals. In this article we introduce a thermodynamic method for estimating the solubilities of model plant surface constituents and relating them to the effects of agrochemicals. Results Following the van Krevelen and Hoftyzer method, we calculated the solubility parameters of three model plant species and eight compounds that differ in hydrophobicity and polarity. In addition, intact tissues were examined by scanning electron microscopy and the surface free energy, polarity, solubility parameter and work of adhesion of each were calculated from contact angle measurements of three liquids with different polarities. By comparing the affinities between plant surface constituents and agrochemicals derived from (a) theoretical calculations and (b) contact angle measurements we were able to distinguish the physical effect of surface roughness from the effect of the chemical nature of the epicuticular waxes. A solubility parameter model for plant surfaces is proposed on the basis of an increasing gradient from the cuticular surface towards the underlying cell wall. Conclusions The procedure enabled us to predict the interactions among agrochemicals, plant surfaces, and cuticular and cell wall components, and promises to be a useful tool for improving our understanding of biological surface interactions. PMID:23151272

Estimation of the solubility parameters of model plant surfaces and agrochemicals: a valuable tool for understanding plant surface interactions.

PubMed

Khayet, Mohamed; Fernández, Victoria

2012-11-14

Most aerial plant parts are covered with a hydrophobic lipid-rich cuticle, which is the interface between the plant organs and the surrounding environment. Plant surfaces may have a high degree of hydrophobicity because of the combined effects of surface chemistry and roughness. The physical and chemical complexity of the plant cuticle limits the development of models that explain its internal structure and interactions with surface-applied agrochemicals. In this article we introduce a thermodynamic method for estimating the solubilities of model plant surface constituents and relating them to the effects of agrochemicals. Following the van Krevelen and Hoftyzer method, we calculated the solubility parameters of three model plant species and eight compounds that differ in hydrophobicity and polarity. In addition, intact tissues were examined by scanning electron microscopy and the surface free energy, polarity, solubility parameter and work of adhesion of each were calculated from contact angle measurements of three liquids with different polarities. By comparing the affinities between plant surface constituents and agrochemicals derived from (a) theoretical calculations and (b) contact angle measurements we were able to distinguish the physical effect of surface roughness from the effect of the chemical nature of the epicuticular waxes. A solubility parameter model for plant surfaces is proposed on the basis of an increasing gradient from the cuticular surface towards the underlying cell wall. The procedure enabled us to predict the interactions among agrochemicals, plant surfaces, and cuticular and cell wall components, and promises to be a useful tool for improving our understanding of biological surface interactions.

Bias correction in the realized stochastic volatility model for daily volatility on the Tokyo Stock Exchange

NASA Astrophysics Data System (ADS)

Takaishi, Tetsuya

2018-06-01

The realized stochastic volatility model has been introduced to estimate more accurate volatility by using both daily returns and realized volatility. The main advantage of the model is that no special bias-correction factor for the realized volatility is required a priori. Instead, the model introduces a bias-correction parameter responsible for the bias hidden in realized volatility. We empirically investigate the bias-correction parameter for realized volatilities calculated at various sampling frequencies for six stocks on the Tokyo Stock Exchange, and then show that the dynamic behavior of the bias-correction parameter as a function of sampling frequency is qualitatively similar to that of the Hansen-Lunde bias-correction factor although their values are substantially different. Under the stochastic diffusion assumption of the return dynamics, we investigate the accuracy of estimated volatilities by examining the standardized returns. We find that while the moments of the standardized returns from low-frequency realized volatilities are consistent with the expectation from the Gaussian variables, the deviation from the expectation becomes considerably large at high frequencies. This indicates that the realized stochastic volatility model itself cannot completely remove bias at high frequencies.

UV-Vis spectroscopy and density functional study of solvent effect on the charge transfer band of the n → σ* complexes of 2-Methylpyridine and 2-Chloropyridine with molecular iodine

NASA Astrophysics Data System (ADS)

Gogoi, Pallavi; Mohan, Uttam; Borpuzari, Manash Protim; Boruah, Abhijit; Baruah, Surjya Kumar

2017-03-01

UV-Vis spectroscopy has established that Pyridine substitutes form n→σ* charge transfer (CT) complexes with molecular Iodine. This study is a combined approach of purely experimental UV-Vis spectroscopy, Multiple linear regression theory and Computational chemistry to analyze the effect of solvent upon the charge transfer band of 2-Methylpyridine-I2 and 2-Chloropyridine-I2 complexes. Regression analysis verifies the dependence of the CT band upon different solvent parameters. Dielectric constant and refractive index are considered among the bulk solvent parameters and Hansen, Kamlet and Catalan parameters are taken into consideration at the molecular level. Density Functional Theory results explain well the blue shift of the CT bands in polar medium as an outcome of stronger donor acceptor interaction. A logarithmic relation between the bond length of the bridging atoms of the donor and the acceptor with the dielectric constant of the medium is established. Tauc plot and TDDFT study indicates a non-vertical electronic transition in the complexes. Buckingham and Lippert Mataga equations are applied to check the Polarizability effect on the CT band.

Solubility of sugars and sugar alcohols in ionic liquids: measurement and PC-SAFT modeling.

PubMed

Carneiro, Aristides P; Held, Christoph; Rodríguez, Oscar; Sadowski, Gabriele; Macedo, Eugénia A

2013-08-29

Biorefining processes using ionic liquids (ILs) require proper solubility data of biomass-based compounds in ILs, as well as an appropriate thermodynamic approach for the modeling of such data. Carbohydrates and their derivatives such as sugar alcohols represent a class of compounds that could play an important role in biorefining. Thus, in this work, the pure IL density and solubility of xylitol and sorbitol in five different ILs were measured between 288 and 339 K. The ILs under consideration were 1-ethyl-3-methylimidazolium dicyanamide, 1-butyl-3-methylimidazolium dicyanamide ([bmim][DCA]), Aliquat dicyanamide, trihexyltetradecylphosphonium dicyanamide, and 1-ethyl-3-methylimidazolium trifluoroacetate. Comparison with the literature data was performed, showing good agreement. With the exception of [bmim][DCA], the solubility of these sugar alcohols in the other ILs is presented for the first time. The measured data as well as previously published solubility data of glucose and fructose in these ILs were modeled by means of PC-SAFT using a molecular-based associative approach for ILs. PC-SAFT was used in this work as it has shown to be applicable to model the solubility of xylitol and sorbitol in ILs (Paduszyński; et al. J. Phys. Chem. B 2013, 117, 7034-7046). For this purpose, three pure IL parameters were fitted to pure IL densities, activity coefficients of 1-propanol at infinite dilution in ILs, and/or xylitol solubility in ILs. This approach allows accurate modeling of the pure IL data and the mixture data with only one binary interaction parameter k(ij) between sugar and the IL or sugar alcohol and the IL. In cases where only the pure IL density and activity coefficients of 1-propanol at infinite dilution in ILs were used for the IL parameter estimation, the solubility of the sugars and sugar alcohols in the ILs could be predicted (k(ij) = 0 between sugar and the IL or sugar alcohol and the IL) with reasonable accuracy.

Regulation of immune cells in the uterus during pregnancy in ruminants.

PubMed

Hansen, P J

2007-03-01

Pregnancy results in a change in number and function of immune cells in utero that potentially affects fetal survival and uterine defense mechanisms postpartum. These changes are driven by local signals from the conceptus as well as from hormonal changes mediated by the placenta or maternal system. In sheep, for example, macrophages accumulate in the uterine endometrium during pregnancy (Tekin and Hansen, 2004). Use of a unilaterally pregnant model, in which pregnancy is surgically confined to 1 uterine horn, has revealed that accumulation of macrophages is due to systemic signals (numbers of cells in the nonpregnant uterine horn of the unilaterally pregnant ewe higher than amounts in uteri of nonpregnant ewes) and locally produced signals (number of cells in the uterus of unilaterally ligated ewes higher in the pregnant horn than in the nonpregnant horn; Tekin and Hansen, 2004). Gamma-delta T cells also accumulate in uterine epithelium during pregnancy as a result of unidentified systemic signals (Lee et al., 1992; Majewski et al., 2001). These cells may participate in growth of the conceptus, immunosuppression, or placental detachment at parturition. One of the key regulators of uterine immune function is progesterone. In sheep, progesterone can block tissue graft rejection in utero when injected to achieve concentrations too low to directly inhibit lymphocyte proliferation (Majewski and Hansen, 2002; Padua et al., 2005). Progesterone probably inhibits uterine immune responses in sheep indirectly by inducing secretion of a member of the serine proteinase inhibitor family called uterine serpin from the endometrial epithelium. Uterine serpin can block lymphocyte proliferation in vitro in sheep (Peltier et al., 2000) and natural killer cell-mediated abortion in vivo in mice (Liu and Hansen, 1993). Uterine serpin is also present in cattle, goats, and pigs, but its role in immune function in these species has not been documented. The relevance of changes in uterine immune function to the reproductive and immune status of ruminants has not been fully established. There is evidence for immunological causes of pregnancy loss associated with cloned fetuses (Hill et al., 2002) and with mastitis (Hansen et al., 2004), but it is not known whether inappropriate recognition of alloantigens on the conceptus is an important cause of pregnancy loss. It is also possible that downregulation of uterine immune function during pregnancy can lead to a postpartum uterus with a compromised capacity for preventing establishment of infectious disease. Thus, optimal immune function in utero requires a balance between the need to maintain effective immune surveillance and effector mechanisms with the requirement that immunological responses leading to conceptus demise are minimized.

Combining MOSCED with molecular simulation free energy calculations or electronic structure calculations to develop an efficient tool for solvent formulation and selection

NASA Astrophysics Data System (ADS)

Cox, Courtney E.; Phifer, Jeremy R.; Ferreira da Silva, Larissa; Gonçalves Nogueira, Gabriel; Ley, Ryan T.; O'Loughlin, Elizabeth J.; Pereira Barbosa, Ana Karolyne; Rygelski, Brett T.; Paluch, Andrew S.

2017-02-01

Solubility parameter based methods have long been a valuable tool for solvent formulation and selection. Of these methods, the MOdified Separation of Cohesive Energy Density (MOSCED) has recently been shown to correlate well the equilibrium solubility of multifunctional non-electrolyte solids. However, before it can be applied to a novel solute, a limited amount of reference solubility data is required to regress the necessary MOSCED parameters. Here we demonstrate for the solutes methylparaben, ethylparaben, propylparaben, butylparaben, lidocaine and ephedrine how conventional molecular simulation free energy calculations or electronic structure calculations in a continuum solvent, here the SMD or SM8 solvation model, can instead be used to generate the necessary reference data, resulting in a predictive flavor of MOSCED. Adopting the melting point temperature and enthalpy of fusion of these compounds from experiment, we are able to predict equilibrium solubilities. We find the method is able to well correlate the (mole fraction) equilibrium solubility in non-aqueous solvents over four orders of magnitude with good quantitative agreement.

Combining MOSCED with molecular simulation free energy calculations or electronic structure calculations to develop an efficient tool for solvent formulation and selection.

PubMed

Cox, Courtney E; Phifer, Jeremy R; Ferreira da Silva, Larissa; Gonçalves Nogueira, Gabriel; Ley, Ryan T; O'Loughlin, Elizabeth J; Pereira Barbosa, Ana Karolyne; Rygelski, Brett T; Paluch, Andrew S

2017-02-01

Solubility parameter based methods have long been a valuable tool for solvent formulation and selection. Of these methods, the MOdified Separation of Cohesive Energy Density (MOSCED) has recently been shown to correlate well the equilibrium solubility of multifunctional non-electrolyte solids. However, before it can be applied to a novel solute, a limited amount of reference solubility data is required to regress the necessary MOSCED parameters. Here we demonstrate for the solutes methylparaben, ethylparaben, propylparaben, butylparaben, lidocaine and ephedrine how conventional molecular simulation free energy calculations or electronic structure calculations in a continuum solvent, here the SMD or SM8 solvation model, can instead be used to generate the necessary reference data, resulting in a predictive flavor of MOSCED. Adopting the melting point temperature and enthalpy of fusion of these compounds from experiment, we are able to predict equilibrium solubilities. We find the method is able to well correlate the (mole fraction) equilibrium solubility in non-aqueous solvents over four orders of magnitude with good quantitative agreement.

Leprosy

MedlinePlus

... Seniors, WomenTags: ancient infections, blindness, chronic granulomatous disease, chronic infection, hand and foot deformities, hansen's disease, infections, leprosy, mycobacterium, rashes, skin lesions, testicle damage November 1, 2009 Copyright © American ...

Fight for survival: the life of a Hansen's disease sufferer through his correspondence with Adolpho Lutz.

PubMed

Benchimol, Jaime Larry; Sá, Magali Romero; Alves da Cruz, Mônica de Souza; Magalhàes de Andrade, Márcio

2003-01-01

This project presents the complete set of letters between the family of a Hansen's disease (leprosy) sufferer in the state of Maranhão, in the Northeast of Brazil, and the doctor and bacteriologist Adolpho Lutz. For more than twenty years Fabricio Caldas de Oliveira and Numa Pires de Oliveira, father and son, exchanged a steady flow of letters with the scientist in pursuit of a cure for the disease that had assailed Numa since childhood. The 24 letters compiled here paint a unique portrait of the medical and social drama confronted by this family, and the results of the use of chaulmoogra oil and other medications in their search for alternative treatments.

Anti-social welfare functions: a reply to Hansen et al.

PubMed

Edlin, Richard

2004-09-01

We could reasonably expect society to give at least the same weight to the marginal utility of the poor as to the rich, and to the marginal utility of the ill as compared to the healthy. Whilst Hansen et al. [Journal of Health Economics (2004)], may be said to link CEA and CBA within a welfarist framework, the assumptions they require are inconsistent with these types of ethical preferences. Thus, the degree to which they employ a reasonable social welfare function is doubtful. This paper argues that any link between CEA and CBA will occur not within a welfarist framework but instead within a non-welfarist one in which it is unlikely that CBA results could be easily transformed into cost-effectiveness ratios.

Investigation of the relationships between the thermodynamic phase behavior and gelation behavior of a series of tripodal trisamide compounds

NASA Astrophysics Data System (ADS)

Feng, Li

Low molecular weight organic gelators(LMOGs) are important due to potential applications in many fields. Currently, most of the major studies focus on the empirical explanation of the crystallization for gelator assembly formation and morphologies, few efforts have been devoted to the thermodynamic phase behaviors and the effect of the non-ideal solution behavior on the structure of the resultant gels. In this research, tripodal trisamide compounds, synthesized from tris(2-aminoethyl)amine (TREN) by condensation with different acid chlorides, were studied as model LMOGs due to the simple one-step reaction and the commercially available chemical reactants. Gelation of organic solvents was investigated as a function of concentration and solvent solubility parameter.It has been found that the introduction of branches or cyclic units have dramatically improves the gelation ability compared to linear alkyl peripheral units. Fitting the liquidus lines using the regular solution model and calculation of the trisamide solubility parameter using solubility parameter theory gave good agreement with the trisamide solubility parameter calculated by group contribution methods. These results demonstrate that non-ideal solution behavior is an important factor in the gelation behavior of low molecular mass organic gelators. Understanding and controlling the thermodynamics and phase behaviors of the gel systems will provide effective ways to produce new efficient LMOGs in the future.

Investigations on the viscoelastic performance of pressure sensitive adhesives in drug-in-adhesive type transdermal films.

PubMed

Wolff, Hans-Michael; Irsan; Dodou, Kalliopi

2014-08-01

We aimed to investigate the effect of solubility parameter and drug concentration on the rheological behaviour of drug-in-adhesive films intended for transdermal application. Films were prepared over a range of drug concentrations (5%, 10% and 20% w/w) using ibuprofen, benzoic acid, nicotinic acid and lidocaine as model drugs in acrylic (Duro-Tak 87-4287 and Duro-Tak 87900A) or silicone (Bio-PSA 7-4301 and Bio-PSA 7-4302) pressure sensitive adhesives (PSAs). Saturation status of films was determined using light microscopy. Viscoelastic parameters were measured in rheology tests at 32°C. Subsaturated films had lower viscoelastic moduli whereas saturated films had higher moduli than the placebo films and/or a concentration-dependent increase in their modulus. Saturation concentration of each drug in the films was reflected by decreasing/increasing viscoelastic patterns. The viscoelastic windows (VWs) of the adhesive and drug-in-adhesive films clearly depicted the effect of solubility parameter differences, molar concentration of drug in the adhesive film and differences in PSA chemistry. Drug solubility parameters and molar drug concentrations have an impact on rheological patterns and thus on the adhesive performance of tested pressure sensitive adhesives intended for use in transdermal drug delivery systems. Use of the Flory equation in its limiting form was appropriate to predict drug solubility in the tested formulations.

Determination of the solubility parameter of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate by inverse gas chromatography.

PubMed

Ma, Xiaohong; Wang, Qiang; Li, Xiaoping; Tang, Jun; Zhang, Zhengfang

2015-11-01

Thermodynamic properties of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM] BF4) were determined via inverse gas chromatography (IGC). Two groups of solvents with different chemical natures and polarities were used to obtain information about [BMIM] BF4-solvent interactions. The specific retention volume, molar heat of sorption, weight fraction activity coefficient, Flory-Huggins interaction parameter as well as solubility parameter were also determined in a temperature range of 333 - 373 K. The results showed that the selected solvents n-C10 to n-C12, carbon tetrachloride, cyclohexane and toluene were poor solvents for [BMIM] BF4, while dichloromethane, acetone, chloroform, methyl acetate, ethanol and methanol were favorite solvents for [BMIM] BF4. In addition, the solubility parameter of [ BMIM] BF4 was determined as 23.39 (J/cm3)0.5 by the extrapolation at 298 K. The experiment proved that IGC was a simple and accurate method to obtain the thermodynamic properties of ionic liquids. This study could be used as a reference to the application and research of the ionic liquids.

[Determination of the solubility parameter of organosolv lignin by inverse gas chromatography].

PubMed

Yu, Yachen; Li, Kunlan; Ma, Yingchong; Wei, Ligang

2013-02-01

An inverse gas chromatographic (IGC) method has been used to measure the solubility parameters (delta2) of organosolv lignin at the absolute temperatures from 333.15 K to 373.15 K. The test probe solvents were n-octane (n-C8), n-decane (n-C10), n-dodecane (n-C12), and n-tetradecane (n-C14). The specific retention volumes of the solvents (Vg0), the molar enthalpy of sorption (deltaH1S), the partial molar enthalpy of mixing at infinite dilution (deltaH1infinity), the molar enthalpy of vaporization (deltaHv), the activity coefficients at infinite dilution (Omega1- infinity), and Flory-Huggins inter action parameters (chi12infinity) between organosolv lignin and probe solvents were obtained. The results showed that the above four probes are poor solvents for organosolv lignin; at the same temperature, the chi12infinity reduced with the increase of the carbon number of probe solvents. The average solubility parameter of organosolv lignin was determined as 19.03 (J x cm(-3))1/2.

Pluto's Volatile Transport

NASA Astrophysics Data System (ADS)

Young, Leslie

2012-10-01

Pluto's varying subsolar latitude and heliocentric distance leads to large variations in the surface volatile distribution and surface pressure. I present results of new volatile transport models (Young 2012a, b). The models include insolation, thermal emission, subsurface conduction, heating of a volatile slab, internal heat flux, latent heat of sublimation, and strict global mass balance. Numeric advances include initial conditions that allow for rapid convergence, efficient computation with matrix arithmetic, and stable Crank-Nicholson timesteps for both bare and volatile-covered areas. Runs of the model show six distinct seasons on Pluto. (1) As Pluto approaches perihelion, the volatiles on the old winter pole (the Rotational North Pole, RNP) becomes more directly illuminated , and the pressure and albedo rise rapidly. (2) When a new ice cap forms on the Rotational South Pole, RSP, volatiles are exchanged between poles. The pressure and albedo change more slowly. (3) When all volatiles have sublimed from the RNP, the albedo and pressure drop rapidly. (4-6) A similar pattern is repeated near aphelion with a reversal of the roles and the poles. I will compare results with earlier Pluto models of Hansen and Paige (1996), show the dependence on parameters such as substrate inertia, and make predictions for the New Horizons flyby of Pluto in 2015. This work was supported, in part, by funding from NASA Planetary Atmospheres Grant NNG06GF32G and the Spitzer project (JPL research support Agreement 1368573). Hansen, C. J. and D. A. Paige 1996. Seasonal Nitrogen Cycles on Pluto. Icarus 120, 247-265. Young, L. A. 2012a. Volatile transport on inhomogeneous surfaces: I - Analytic expressions, with application to Pluto’s day. Icarus, in press Young, L. A. 2012b. Volatile transport on inhomogeneous surfaces: II. Numerical calculations, with application to Pluto's season. In preparation.

Efficient and accurate local single reference correlation methods for high-spin open-shell molecules using pair natural orbitals

NASA Astrophysics Data System (ADS)

Hansen, Andreas; Liakos, Dimitrios G.; Neese, Frank

2011-12-01

A production level implementation of the high-spin open-shell (spin unrestricted) single reference coupled pair, quadratic configuration interaction and coupled cluster methods with up to doubly excited determinants in the framework of the local pair natural orbital (LPNO) concept is reported. This work is an extension of the closed-shell LPNO methods developed earlier [F. Neese, F. Wennmohs, and A. Hansen, J. Chem. Phys. 130, 114108 (2009), 10.1063/1.3086717; F. Neese, A. Hansen, and D. G. Liakos, J. Chem. Phys. 131, 064103 (2009), 10.1063/1.3173827]. The internal space is spanned by localized orbitals, while the external space for each electron pair is represented by a truncated PNO expansion. The laborious integral transformation associated with the large number of PNOs becomes feasible through the extensive use of density fitting (resolution of the identity (RI)) techniques. Technical complications arising for the open-shell case and the use of quasi-restricted orbitals for the construction of the reference determinant are discussed in detail. As in the closed-shell case, only three cutoff parameters control the average number of PNOs per electron pair, the size of the significant pair list, and the number of contributing auxiliary basis functions per PNO. The chosen threshold default values ensure robustness and the results of the parent canonical methods are reproduced to high accuracy. Comprehensive numerical tests on absolute and relative energies as well as timings consistently show that the outstanding performance of the LPNO methods carries over to the open-shell case with minor modifications. Finally, hyperfine couplings calculated with the variational LPNO-CEPA/1 method, for which a well-defined expectation value type density exists, indicate the great potential of the LPNO approach for the efficient calculation of molecular properties.

Experimental Solubility Approach to Determine PDMS-Water Partition Constants and PDMS Activity Coefficients.

PubMed

Grant, Sharon; Schacht, Veronika J; Escher, Beate I; Hawker, Darryl W; Gaus, Caroline

2016-03-15

Freely dissolved aqueous concentration and chemical activity are important determinants of contaminant transport, fate, and toxic potential. Both parameters are commonly quantified using Solid Phase Micro-Extraction (SPME) based on a sorptive polymer such as polydimethylsiloxane (PDMS). This method requires the PDMS-water partition constants, KPDMSw, or activity coefficient to be known. For superhydrophobic contaminants (log KOW >6), application of existing methods to measure these parameters is challenging, and independent measures to validate KPDMSw values would be beneficial. We developed a simple, rapid method to directly measure PDMS solubilities of solid contaminants, SPDMS(S), which together with literature thermodynamic properties was then used to estimate KPDMSw and activity coefficients in PDMS. PDMS solubility for the test compounds (log KOW 7.2-8.3) ranged over 3 orders of magnitude (4.1-5700 μM), and was dependent on compound class. For polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins (PCDDs), solubility-derived KPDMSw increased linearly with hydrophobicity, consistent with trends previously reported for less chlorinated congeners. In contrast, subcooled liquid PDMS solubilities, SPDMS(L), were approximately constant within a compound class. SPDMS(S) and KPDMSw can therefore be predicted for a compound class with reasonable robustness based solely on the class-specific SPDMS(L) and a particular congener's entropy of fusion, melting point, and aqueous solubility.

Physicochemical properties/descriptors governing the solubility and partitioning of chemicals in water-solvent-gas systems. Part 2. Solubility in 1-octanol.

PubMed

Raevsky, O A; Perlovich, G L; Schaper, K-J

2007-01-01

On the basis of octanol solubility data (log S(o)) for 218 structurally diverse solid chemicals it was shown that the exclusive consideration of melting points did not provide satisfactory results in the quantitative prediction of this parameter (s = 0.92). The application of HYBOT physicochemical descriptors separately (s = 0.94) and together with melting points (s = 0.70) in the framework of a common regression model also was not successful, although contributions of volume-related and H-bond terms to solubility in octanol were identified. It was proposed that the main reason for such behaviour was the different crystal lattice interaction of different classes of chemicals. Successful calculations of the solubility in octanol of chemicals of interest were performed on the basis of the experimental solubility of structurally/physicochemically/numerically similar nearest neighbours with consideration of their difference in physicochemical parameters (molecular polarisability, H-bond acceptor and donor factors (s = 0.66)) and of these descriptors together with melting point differences (s = 0.38). Good results were obtained for all compounds having nearest neighbours with sufficient similarity, expressed by Tanimoto indexes, and by distances in the scaled 3D descriptor space. Obviously the success of this approach depends on the size of the database.

Novel Co(II) phthalocyanines of extended periphery and their water-soluble derivatives. Synthesis, spectral properties and catalytic activity

NASA Astrophysics Data System (ADS)

Filippova, Anna; Vashurin, Artur; Znoyko, Serafima; Kuzmin, Ilya; Razumov, Mikhail; Chernova, Alena; Shaposhnikov, Gennady; Koifman, Oscar

2017-12-01

Novel complexes of cobalt and copper with substituted phthalocyanines were synthesized and characterized. Their water-soluble derivatives were obtained by sulfonation under mild conditions and structurally proved. Aggregation equilibrium in water mediums was shown and influence of geometrical and electron parameters of macroheterocycle peripheral substituents on these processes was established. Catalytic activity upon liquid-phase oxidation of N,N-diethylcarbamodithiolate to thiuram E was studied. Kinetic parameters of substrate oxidation in presence of cobalt phthalocyanines were considered.

Application of the solubility parameter concept to the design of chemiresistor arrays

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

Hughes, R.C.; Yelton, W.G.; Ricco, A.J.

1998-04-01

Arrays of unheated chemically sensitive resistors (chemiresistors) can serve as extremely small, low power consumption sensors with simple read out electronics. Most work has focused on the exotic polymeric organic metals, but here the authors report new results on carbon loaded polymer composites, as well as polymeric ionic conductors. They use the solubility parameter concept to understand and categorize the chemiresistor responses and, in particular, they compare chemiresistors fabricated from polyisobutylene (PIB) to results from PIB coated acoustic wave sensors.

Solubility of (+/-)-ibuprofen and S (+)-ibuprofen in the presence of cosolvents and cyclodextrins.

PubMed

Nerurkar, Jayanti; Beach, J W; Park, M O; Jun, H W

2005-01-01

Aqueous solubility is an important parameter for the development of liquid formulations and in the determination of bioavailability of oral dosage forms. Ibuprofen (IB), a nonsteroidal anti-inflammatory drug, is a chiral molecule and is currently used clinically as a racemate (racIB). However, the S form of ibuprofen or S(+)-ibuprofen (SIB) is the biologically active isomer and is primarily responsible for the antiinflammatory activity. Phase solubility studies were carried out to compare the saturation solubilities of racIB and SIB in the presence of common pharmaceutical solvents such as glycerol, sorbitol solution, propylene glycol (PG), and polyethylene glycol (PEG 300) over the range of 20% to 80% v/v in aqueous based systems. The solubilities of the two compounds were also compared in the presence of cyclodextrins such as beta cyclodextrin (CD), hydroxypropyl beta cyclodextrin (HPCD), and beta cyclodextrin sulfobutyl ether sodium salt (CDSB) over the range of 5% to 25% w/v. Solubility determinations were carried at 25 degrees C and 37 degrees C. Cosolvents exponentially increased the solubility of both SIB and racIB, especially in the presence of PG and PEG 300. Glycerol was not very effective in increasing the aqueous solubilities of both compounds, whereas sorbitol solution had a minimal effect on their solubility. PG and PEG 300 increased the solubility of SIB by 400-fold and 1500-fold, respectively, whereas the rise in solubility for racIB was 193-fold and 700-fold, respectively, at 25 degrees C for the highest concentration of the cosolvents used (80% v/v). Of the two compounds studied, higher equilibrium solubilities were observed for SIB as compared with racIB. The derivatized cyclodextrins increased the aqueous solubility of racIB and SIB in a concentration-dependent manner giving AL type of phase diagrams. The phase solubility diagrams indicated the formation of soluble inclusion complexes between the drugs and HPCD and CDSB, which was of 1:1 stoichiometry. The addition of underivatized CD reduced the solubility of racIB and SIB via the formation of an insoluble complex. The S form formed more stable complexes with HPCD and CDSB as compared with raclB. The solubilization process is discussed in terms of solvent polarity and differential solid-state structure of raclB and SIB. The thermodynamic parameters for the solubilization process are presented.

Experimental and theoretical charge density studies at subatomic resolution.

PubMed

Fischer, A; Tiana, D; Scherer, W; Batke, K; Eickerling, G; Svendsen, H; Bindzus, N; Iversen, B B

2011-11-17

Analysis of accurate experimental and theoretical structure factors of diamond and silicon reveals that the contraction of the core shell due to covalent bond formation causes significant perturbations of the total charge density that cannot be ignored in precise charge density studies. We outline that the nature and origin of core contraction/expansion and core polarization phenomena can be analyzed by experimental studies employing an extended Hansen-Coppens multipolar model. Omission or insufficient treatment of these subatomic charge density phenomena might yield erroneous thermal displacement parameters and high residual densities in multipolar refinements. Our detailed studies therefore suggest that the refinement of contraction/expansion and population parameters of all atomic shells is essential to the precise reconstruction of electron density distributions by a multipolar model. Furthermore, our results imply that also the polarization of the inner shells needs to be adopted, especially in cases where second row or even heavier elements are involved in covalent bonding. These theoretical studies are supported by direct multipolar refinements of X-ray powder diffraction data of diamond obtained from a third-generation synchrotron-radiation source (SPring-8, BL02B2).

Analytical treatment of neutrino asymmetry equilibration from flavor oscillations in the early universe

NASA Astrophysics Data System (ADS)

Wong, Yvonne Y.

2002-07-01

A recent numerical study by A. D. Dolgov, S. H. Hansen, S. Pastor, S. T. Petcov, G. G. Raffelt, and D. V. Semikoz (DHPPRS) [Nucl. Phys. B632, 363 (2002)] found that complete or partial equilibrium between all active neutrino flavors can be achieved before the big bang nucleosynthesis epoch via flavor oscillations, if the oscillation parameters are those inferred from the atmospheric and solar neutrino data, and, in some cases, if θ13 is also sizable. As such, cosmological constraints on the electron neutrino-antineutrino asymmetry are now applicable in all three neutrino sectors. In the present work, we provide an analytical treatment of the scenarios considered in DHPPRS, and demonstrate that their results are stable even for very large initial asymmetries. The equilibration mechanism can be understood in terms of a Mikheyev-Smirnov-Wolfenstein-like effect for a maximally mixed and effectively monochromatic system. We also comment on the DHPPRS's choices of mixing parameters, and their handling of collisional effects, both of which could impinge on the extent of flavor equilibrium.

An improved method for calculating power density in the Fresnel region of circular parabolic reflector antennas

NASA Astrophysics Data System (ADS)

Mize, Johnnie E.

1988-03-01

A computer program is presented which calculates power density in the Fresnel region of circular parabolic reflector antennas. The aperture illumination model is the one-parameter circular distribution developed by Hansen. The program is applicable to the analysis of electrically large, center-fed (or Cassegrain) paraboloids with linearly polarized feeds. The scalar Kirchoff diffraction integral is solved numerically by Romberg integration for points both on and perpendicular to the antenna boresight. Axial results cannot be directly compared to any others obtained with this illumination model, but they are consistent with what is expected in the Fresnel region where a quadratic must be added to the linear phase term of the integral expression. Graphical results are presented for uniform illumination and for cases where the first sidelobe ratio is 20, 25, 30, and 35 dB.

Structural analysis according to reduced data: VIII. Refinement of the extended model of aspherical atoms

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

Dudka, A. P.

A program for the refinement of the model of aspherical atoms within the Stewart-Hansen-Coppens formalism has been developed. Deformation scattering up to the 8th expansion order in multipoles has been taken into account for the first time. The program was tested for 11 crystals. The effect of the result of interpolation of radial scattering curves on the model parameters is considered. The importance of introduction of multipoles of high (5th-8th) orders into the model for a number of crystals is shown. The use of the extended multipole model for a silicon crystal revealed some new specific features of the electronicmore » structure: consideration of multipoles up to the 7th order makes it possible to explain the intensity of the forbidden 222 reflection.« less

Twelve Foot Subsatellite

NASA Image and Video Library

1958-04-25

Engineer and 12 foot Beacon showing NACA emblem on inflated satelloon . For related information see, Spaceflight Revolution, NASA from Sputnik to Apollo, by James R. Hansen. NASA SP-4308, 1995. p. 173.

Using Goat's Milk, Barley Flour, Honey, and Probiotic to Manufacture of Functional Dairy Product.

PubMed

Ismail, Magdy Mohamed; Hamad, Mohamed Farid; Elraghy, Esraa Mohamed

2017-08-23

Stirred yogurt manufactured using probiotic culture which usually called Rayeb milk in the Middle East region is one of the most important functional fermented milk products. To increase the health and functionality properties to this product, some ingredients like fruits, cereal, and whey protein are used in production. This study was carried out to prepare functional Rayeb milk from goat's milk, barley flour (15%) and honey (4%) mixtures using ABT culture. Also, vanilla and cocoa powder were used as flavorings. Adding barley flour and honey to goat's milk increased curd tension and water-holding capacity and decreased coagulation time and susceptibility to syneresis. The values of carbohydrate, total solids, dietary fiber, ash, total protein, water soluble nitrogen, total volatile fatty acids, unsaturated fatty acids, oleic, linoleic, α-linolenic acids, and antioxidant activity were higher in Rayeb milk supplemented with barley flour and honey than control. The viabilities of Lactobacillus acidophilus and Bifidobacterium lactis Bb12 (Chr. Hansen's Lab A/S) increased in fortified Rayeb milk. The recommended level of 10 7  cfu g -1 of bifidobacteria as a probiotic was exceeded for these samples. Addition of vanilla (0.1%) or cocoa powder (0.5%) improved the sensory properties of fortified Rayeb milk.

Rapeseed Oil as Renewable Resource for Polyol Synthesis

NASA Astrophysics Data System (ADS)

Stirna, Uldis; Fridrihsone, Anda; Misane, Marija; Vilsone, Dzintra

2011-01-01

Vegetable oils are one of the most important platform chemicals due to their accessibility, specific structure of oils and low price. Rapeseed oil (RO) polyols were prepared by amidization of RO with diethanolamine (DEA). To determine the kinetics of amidization reaction, experiments were carried out. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), amine (NH) value was determined. Group contribution method by Fedor‵s was used to calculate solubility parameters, van der Waals volume was calculated by Askadskii. Obtained polyol‵s OH and NH value are from 304 up to 415 mg KOH/g. RO polyols synthesis meets the criteria of "green chemistry". In the present study, reaction of RO amidization with DEA was investigated, as well as optimum conditions for polyol synthesis was established to obtain polyols for polyurethane production. Calculations of solubility parameter and cohesion energy density were calculated, as RO polyols will be used as side chains in polymers, and solubility parameter will be used to explain properties of polymers.

Nonequilibrium boundary layer at a stagnation point for a hydrogen-helium stream over ablating graphite

NASA Technical Reports Server (NTRS)

Liu, T.-M.; Davy, W. C.

1974-01-01

The nonequilibrium axisymmetric stagnation point boundary layer over an ablating graphite surface is considered. The external stream is a high temperature mixture of hydrogen and helium. Variable thermodynamic and transport properties are assumed. Lennard-Jones potential model is used to calculate the transport coefficients of each species. Although the mixture rules for viscosity of the gas mixture are used, the weighting functions are more sophisticated than those commonly employed. For the conductivity of the mixture, generalized Wassiljewa coefficients are used. Seven species with 28 dissociation/recombination reactions are considered. Hansen's model for the dissociation rate constants is employed. The recombination rate constants are obtained by invoking detailed balance principles assisted by the JANAF thermodynamic data and the Hansen-Pearson thermodynamic data for C3.

Oral history and memories of Hansen's disease patients in two Colombian leper colonies: life trajectories, conflicts and resistance strategies.

PubMed

Botero-Jaramillo, Natalia; Mora-Blanco, Jessica; Quesada-Jiménez, Nelson Daniel

2017-01-01

The paper examines the oral history of Hansen's disease in two Colombian communities that were leper colonies until 1961. The oral history around the disease allows us to connect individuals' memories with collective memory. This history remains an oral one, and few academic studies have documented it. We use oral history as a qualitative research method in order to analyze how the patients and those who lived alongside them positioned themselves in terms of the disease and how it permeated their entire existence, re-signifying the concepts of health and disease, normality and abnormality. We examine how, over the course of their lives, they engaged in resistance strategies that allowed them to get closer to normality, in their own sociocultural terms.

Drug Solubility: Importance and Enhancement Techniques

PubMed Central

Savjani, Ketan T.; Gajjar, Anuradha K.; Savjani, Jignasa K.

2012-01-01

Solubility, the phenomenon of dissolution of solute in solvent to give a homogenous system, is one of the important parameters to achieve desired concentration of drug in systemic circulation for desired (anticipated) pharmacological response. Low aqueous solubility is the major problem encountered with formulation development of new chemical entities as well as for the generic development. More than 40% NCEs (new chemical entities) developed in pharmaceutical industry are practically insoluble in water. Solubility is a major challenge for formulation scientist. Any drug to be absorbed must be present in the form of solution at the site of absorption. Various techniques are used for the enhancement of the solubility of poorly soluble drugs which include physical and chemical modifications of drug and other methods like particle size reduction, crystal engineering, salt formation, solid dispersion, use of surfactant, complexation, and so forth. Selection of solubility improving method depends on drug property, site of absorption, and required dosage form characteristics. PMID:22830056

Thermodynamic Study of Solid-Liquid Equilibrium in NaCl-NaBr-H2O System at 288.15 K

NASA Astrophysics Data System (ADS)

Li, Dan; Meng, Ling-zong; Deng, Tian-long; Guo, Ya-fei; Fu, Qing-Tao

2018-06-01

The solubility data, composition of the solid solution and refractive indices of the NaCl-NaBr-H2O system at 288.15 K were studied with the isothermal equilibrium dissolution method. The solubility diagram and refractive index diagram of this system were plotted at 288.15 K. The solubility diagram consists of two crystallization zones for solid solution Na(Cl,Br) · 2H2O and Na(Cl,Br), one invariant points cosaturated with two solid solution and two univariant solubility isothermal curves. On the basis of Pitzer and Harvie-Weare (HW) chemical models, the composition equations and solubility equilibrium constant equations of the solid solutions at 288.15 K were acquired using the solubility data, the composition of solid solutions, and binary Pitzer parameters. The solubilities calculated using the new method combining the equations are in good agreement with the experimental data.

Solubility of Naproxen in Polyethylene Glycol 200 + Water Mixtures at Various Temperatures

PubMed Central

Panahi-Azar, Vahid; Soltanpour, Shahla; Martinez, Fleming; Jouyban, Abolghasem

2015-01-01

The solubility of naproxen in binary mixtures of polyethylene glycol 200 (PEG 200) + water at the temperature range from 298.0 K to 318.0 K were reported. The combinations of Jouyban-Acree model + van’t Hoff and Jouyban-Acree model + partial solubility parameters were used to predict the solubility of naproxen in PEG 200 + water mixtures at different temperatures. Combination of Jouyban-Acree model with van’t Hoff equation can be used to predict solubility in PEG 200 + water with only four solubility data in mono-solvents. The obtained solubility calculation errors vary from ~ 17 % up to 35 % depend on the number of required input data. Non-linear enthalpy-entropy compensation was found for naproxen in the investigated solvent system and the Jouyban−Acree model provides reasonably accurate mathematical descriptions of the thermodynamic data of naproxen in the investigated binary solvent systems. PMID:26664370

Solubility of gases and liquids in glassy polymers.

PubMed

De Angelis, Maria Grazia; Sarti, Giulio C

2011-01-01

This review discusses a macroscopic thermodynamic procedure to calculate the solubility of gases, vapors, and liquids in glassy polymers that is based on the general procedure provided by the nonequilibrium thermodynamics for glassy polymers (NET-GP) method. Several examples are presented using various nonequilibrium (NE) models including lattice fluid (NELF), statistical associating fluid theory (NE-SAFT), and perturbed hard sphere chain (NE-PHSC). Particular applications illustrate the calculation of infinite-dilution solubility coefficients in different glassy polymers and the prediction of solubility isotherms for different gases and vapors in pure polymers as well as in polymer blends. The determination of model parameters is discussed, and the predictive abilities of the models are illustrated. Attention is also given to the solubility of gas mixtures and solubility isotherms in nanocomposite mixed matrices. The fractional free volume determined from solubility data can be used to correlate solute diffusivities in mixed matrices.

The solubility of hen egg-white lysozyme

NASA Technical Reports Server (NTRS)

Howard, Sandra B.; Twigg, Pamela J.; Baird, James K.; Meehan, Edward J.

1988-01-01

The equilibrium solubility of chicken egg-white lysozyme in the presence of crystalline solid state was determined as a function of NaCl concentration, pH, and temperature. The solubility curves obtained represent a region of the lysozyme phase diagram. This diagram makes it possible to determine the supersaturation of a given set of conditions or to achieve identical supersaturations by different combinations of parameters. The temperature dependence of the solubility permits the evaluation of Delta-H of crystallization. The data indicate a negative heat of crystallization for the tetragonal crystal form but a positive heat of crystallization for the high-temperature orthorhombic form.

Preliminary evaluation of in vitro cytotoxicity and in vivo antitumor activity of Xanthium strumarium in transplantable tumors in mice.

PubMed

Aranjani, Jesil Mathew; Manuel, Atulya; Mallikarjuna Rao, Chamallamudi; Udupa, Nayanabhirama; Rao, Josyula Venkata; Joy, Ann Mary; Gandhi, Prajay; Radhakrishnan, Ethiraj Kannat

2013-01-01

In the present study, active fractions of the methanolic extract of Xanthium strumarium (XS) showing potent cytotoxicity were determined using microculture tetrazolium (MTT) and sulforhodamine B (SRB) assays in selected cancer cell lines. The active fractions viz., chloroform soluble fraction of root (CEXSR), hexane soluble fraction of leaf (HEXSL), hexane soluble fraction of fruits (HEXSF) and chloroform soluble fraction of fruits (CEXSF) of XS were tested in transplantable animal tumor models for their antitumor potential. Dalton's ascitic lymphoma (DLA) cells were used to induce solid and liquid (ascites) tumor in mice. The tumor bearing animals were treated with active fractions at two dose levels (100 and 200 mg/kg). The antitumor activities of the active fractions in tumor bearing animals were monitored with parameters such as body weight and increase in life-span as well as biochemical and hematological modalities (in the case of liquid tumor). Tumor incidence and tumor volume were the parameters monitored in the case of the solid tumor model. The results were analyzed by one-way ANOVA followed by Tukey's post hoc test. The extracts were found to increase the life-span of tumor bearing animals and restore the altered hematological and biochemical parameters significantly.

Genetics Home Reference: otulipenia

MedlinePlus

... AND DERMATOSIS SYNDROME Sources for This Page Damgaard RB, Walker JA, Marco-Casanova P, Morgan NV, Titheradge ... K, Elliott PR, Glockner L, Fiil BK, Damgaard RB, Kulathu Y, Wauer T, Hospenthal MK, Gyrd-Hansen ...

Spatial and Temporal Analysis of Industrial Forest Clearcuts in the Conterminous United States

NASA Astrophysics Data System (ADS)

Huo, L. Z.; Boschetti, L.

2015-12-01

Remote sensing has been widely used for mapping and characterizing changes in forest cover, but the available remote sensing forest change products are not discriminating between deforestation (permanent transition from forest to non forest) and industrial forest management (logging followed by regrowth, with no land cover/ land use class change) (Hansen et al, 2010). Current estimates of carbon-equivalent emissions report the contribution of deforestation as 12% of total anthropogenic carbon emissions (van der Werf et al., 2009), but accurate monitoring of forest carbon balance should discriminate between land use change related to forest natural disturbances, and forest management. The total change in forest cover (Gross Forest Cover Loss, GFLC) needs to be characterized based on the cause (natural/human) and on the outcome of the change (regeneration to forest/transition to non/forest)(Kurtz et al, 2010). This paper presents the methodology used to classify the forest loss detected by the University of Maryland Global Forest Change product (Hansen, 2013) into deforestation, disturbances (fires, insect outbreaks) and industrial forest clearcuts. The industrial forest clearcuts were subsequently analysed by converting the pixel based detections into objects, and applying patch level metrics (e.g. size, compactness, straightness of boundaries) and contextual measures. The analysis is stratified by region and by dominant forest specie, to highlight changes in the rate of forest resource utilization in the 2003-2013 period covered by the Maryland Forest Cover Change Product. References Hansen, M.C., Stehman, S.V., & Potapov, P.V. (2010). Reply to Wernick et al.: Global scale quantification of forest change. Proceedings of the National Academy of Sciences, 107, E148-E148 Hansen, M.C., Potapov, P.V., Moore, R et al., (2013), "High resolution Global Maps for the 21stCentury Forest Cover Change", Science 342: 850-853 Kurz, W.A. (2010). An ecosystem context for global gross forest cover loss estimates. Proceedings of the National Academy of Sciences, 107, 9025-9026 van der Werf, G.R., Morton, D.C., DeFries, R.S., Olivier, J.G., Kasibhatla, P.S., Jackson, R.B., Collatz, G.J., & Randerson, J. (2009). CO2 emissions from forest loss. Nature Geoscience, 2, 737-738

Dinoflagellate cyst biostratigraphy of the Upper Cretaceous succession in the sub-Arctic region

NASA Astrophysics Data System (ADS)

Radmacher, Wiesława; Tyszka, Jarosław; Mangerud, Gunn; Pearce, Martin

2017-04-01

The study provides a solid basis for the first palynostratigraphic zonation of the Upper Cretaceous sub-Arctic succession. Dinoflagellate cysts from the unique composite section, combining samples from the shallow stratigraphic core 6711/4-U-1 and core-samples from well 6707/10-1 in the Norwegian Sea, were studied and compared to palynological data from the south-western Barents Sea, wells 7119/12-1, 7119/9-1, 7120/7-3, 7120/5-1 and 7121/5-1. Dinoflagellate cysts diagnostic for late Maastrichtian that are missing in the Barents Sea are recorded in both sections in the Norwegian Sea. This adds new valuable data from the time interval often represented by a significant regional hiatus in the area. Seven new and three previously recognised zones are identified, based on top and base occurrence of selected age diagnostic taxa. In addition, one Abundance Subzone is introduced. The biostratigraphic zonation includes: the intra late Albian to intra early Cenomanian Subtilisphaera kalaalliti Interval Zone sensu Nøhr-Hansen (1993); the intra early Cenomanian to intra late Cenomanian Palaeohystrichophora infusorioides-Palaeohystrichophora palaeoinfusa Interval Zone sensu Radmacher et al. (2014); the intra Turonian to ?intra early Coniacian Heterosphaeridium difficile Interval Zone sensu Nøhr-Hansen (2012); the ?intra early Coniacian to late Santonian Dinopterygium alatum Interval Zone sensu Radmacher et al. (2014); the ?early Campanian Palaeoglenodinium cretaceum Interval Zone sensu Radmacher et al. (2014); the intra Campanian Hystrichosphaeridium dowlingii-Heterosphaeridium spp. Interval Zone sensu Radmacher et al. (2015); the intra late Campanian Chatangiella bondarenkoi Interval Zone sensu Radmacher et al. (2014) encompassing the Heterosphaeridium bellii Abundance Subzone; the early Maastrichtian Cerodinium diebelii Interval Zone sensu Nøhr-Hansen (1996) and the intra late Maastrichtian Wodehouseia spinata Range Zone sensu Nøhr-Hansen (1996). The Heterosphaeridium bellii is a newly described species important for biostratigraphical and palaeoenvironmental interpretations. Comparison of the recorded dinoflagellate cyst events with the published data from adjacent areas, such as west and east Greenland, North Sea, offshore eastern Canada and northern Siberia allows for sub-Arctic interregional correlations. This research was partially supported by EEA Financial Mechanism and Norwegian Financial Mechanism and the Research Council of Norway.

Estimation of octanol/water partition coefficient and aqueous solubility of environmental chemicals using molecular fingerprints and machine learning methods

EPA Science Inventory

Octanol/water partition coefficient (logP) and aqueous solubility (logS) are two important parameters in pharmacology and toxicology studies, and experimental measurements are usually time-consuming and expensive. In the present research, novel methods are presented for the estim...

Effects of vehicles and prodrug properties and their interactions on the delivery of 6-mercaptopurine through skin: S6-acyloxymethyl-6-mercaptopurine prodrugs.

PubMed

Waranis, R P; Sloan, K B

1988-03-01

A homologous series of S6-acyloxymethyl-6-mercaptopurine (6-mono-6-MP) and two 9-acyloxymethyl-6-mercaptopurine (9-mono-6-MP) prodrugs have been synthesized and characterized. The ability of the 6-mono-6-MP prodrugs to deliver 6-mercaptopurine (6-MP) through hairless mouse skin from isopropyl myristate (IPM) and propylene glycol (PG) has been evaluated. There was a good correlation between the log experimental permeability coefficients from the diffusion data and calculated solubility parameters of the prodrugs. Although there was no statistical difference between the rates of delivery of 6-MP by the acetyl through valeryl 6-mono-6-MP prodrugs from IPM, the butyryl and valeryl prodrugs were significantly better at delivering 6-MP from PG. For a given solubility parameter value, the 6-mono-6-MP prodrugs were less soluble in water and IPM, and more soluble in PG than the previously studied S6,9-bisacyloxymethyl-6-MP (6,9-bis-6-MP) prodrugs. On the other hand, for a given solubility parameter, the 6,9-bis-6-MP prodrugs were generally more effective at delivering 6-MP from IPM and PG. The single 9-mono-6-MP prodrug that was evaluated was much less effective at delivering 6-MP than either the 6-mono- or 6,9-bis-6-MP prodrugs. Thus, it is much less important to mask the imidazole than the thionamide functional group in 6-MP to enhance the topical delivery of 6-MP using a prodrug approach.

jsc2013e030873

NASA Image and Video Library

2013-05-10

PHOTO DATE: 10 MAY 2013 LOCATION: Neutral Buoyancy Lab - Underwater SUBJECT: NBL EVA dive with Terry Virts and Samantha Cristoforetti in support of ISS ammonia leak trouble-shooting. PHOTOGRAPHER: NBL/Bill Brassard/Kelly Rives/Lauren Hansen

jsc2013e030874

NASA Image and Video Library

2013-05-10

PHOTO DATE: 10 MAY 2013 LOCATION: Neutral Buoyancy Lab - Underwater SUBJECT: NBL EVA dive with Terry Virts and Samantha Cristoforetti in support of ISS ammonia leak trouble-shooting. PHOTOGRAPHER: NBL/Bill Brassard/Kelly Rives/Lauren Hansen

jsc2013e030876

NASA Image and Video Library

2013-05-10

PHOTO DATE: 10 MAY 2013 LOCATION: Neutral Buoyancy Lab - Underwater SUBJECT: NBL EVA dive with Terry Virts and Samantha Cristoforetti in support of ISS ammonia leak trouble-shooting. PHOTOGRAPHER: NBL/Bill Brassard/Kelly Rives/Lauren Hansen

Ray tracing: Experience at SRC

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

Severson, M.

1996-09-01

SHADOW [B. Lai and F. Cerrina, Nucl. Instrum. Methods A {bold 246}, 337 (1986)] is the primary ray-tracing program used at SRC. Ray tracing provides a tremendous amount of information regarding beamline layout, mirror sizes, resolution, alignment tolerances, and beam size at various locations. It also provides a way to check the beamline design for errors. Two recent designs have been ray traced extensively: an undulator-based, 4-meter, normal-incidence monochromator (NIM) [R. Reininger, M.C. Severson, R.W.C. Hansen, W.R. Winter, M.A. Green, and W.S. Trzeciak, Rev. Sci. Instrum. {bold 66}, 2194 (1995)] and an undulator-based, plane-grating monochromator (PGM) [R. Reininger, S.L. Crossley,more » M.A. Lagergren, M.C. Severson, and R.W.C. Hansen, Nucl. Instrum. Methods A {bold 347}, 304 (1994)]. {copyright} {ital 1996 American Institute of Physics.}« less

[Hansen's disease in the northern region of Brazil--1986].

PubMed

Britto, R da S

1989-12-01

Some general facts about Hansen's Disease are presented: in the world, in the Americas, in 1986, with the purpose to focalize on the Northern Region of Brazil (Amazon Valley) where an attempt is made to specify, State, the clinical forms in the active registry, the respective coefficients of Prevalence, about the cases detected during the year, by clinical forms and the correspondent Coefficient of Incidence, the age range of less than 15 years, and above 15 years; and to analyze according to the township in the State of Amazonas in a series of 8 years, from 1979 to 1986, the registered cases under control and also without control, the new cases, by clinical form and Coefficient of Incidence, the positive cases among students in the capital and also in the country, and with more details, still by township and by Public Health Registry, in 1986, with the population, new cases, and Coefficient of Incidence, cases of the active registry, cases under control, Coefficient of Incidence, the relationship between patients/inhabitants, cases according to the decreasing intensity as far as the Prevalence and Health Department Regions: all this to give an idea, in detail, inclusive statistics, of the real position of Hansen's Disease in the Northern Region (Amazon Valley), with the highest figures of Prevalence and even of Incidence, in comparison with other Regions of the country, and to stress the grave situation of the endemic proportions of the disease, in Brazil in general and in that Regions, in particular.

Solubility of alkali metal halides in the ionic liquid [C4C1im][OTf].

PubMed

Kuzmina, O; Bordes, E; Schmauck, J; Hunt, P A; Hallett, J P; Welton, T

2016-06-28

The solubilities of the metal halides LiF, LiCl, LiBr, LiI, NaF, NaCl, NaBr, NaI, KF, KCl, KBr, KI, RbCl, CsCl, CsI, were measured at temperatures ranging from 298.15 to 378.15 K in the ionic liquid 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([C4C1im][OTf]). Li(+), Na(+) and K(+) salts with anions matching the ionic liquid have also been investigated to determine how well these cations dissolve in [C4C1im][OTf]. This study compares the influence of metal cation and halide anion on the solubility of salts within this ionic liquid. The highest solubility found was for iodide salts, and the lowest solubility for the three fluoride salts. There is no outstanding difference in the solubility of salts with matching anions in comparison to halide salts. The experimental data were correlated employing several phase equilibria models, including ideal mixtures, van't Hoff, the λh (Buchowski) equation, the modified Apelblat equation, and the non-random two-liquid model (NRTL). It was found that the van't Hoff model gave the best correlation results. On the basis of the experimental data the thermodynamic dissolution parameters (ΔH, ΔS, and ΔG) were determined for the studied systems together with computed gas phase metathesis parameters. Dissolution depends on the energy difference between enthalpies of fusion and dissolution of the solute salt. This demonstrates that overcoming the lattice energy of the solid matrix is the key to the solubility of inorganic salts in ionic liquids.

[Status of the water-soluble component of the antioxidant defense system in the conditions of 520-day isolation].

PubMed

Morukov, B V; Popov, I N; Levin, G; Markin, A A; Zhuravleva, O A; Kuzichkin, D S

2013-01-01

In the 520-d chamber experiment within the international project Mars-500 blood samples of 6 male test-subjects of 28 to 39 years of age were analyzed for water-soluble antioxidants: total bilirubin and uric acid; in addition, total antioxidant capacity of blood plasma was determined. Maximal values of these parameters were associated with the most stressful periods of the experiment, i.e. adaptation to the life in isolation and confinement, simulation of the egress onto Martian surface, and change of the diet. On attainment of the homeostatic equilibrium the parameters stabilized on levels slightly lower relative to baseline (pre-isolation) values. Therefore, dynamics of the water-soluble antioxidants reflected adequately the homeostatic reactions to and compensation by organism of the effects of the 520-day life in isolation and confinement.

Cross sections for ionization of tetrahydrofuran by protons at energies between 300 and 3000 keV

NASA Astrophysics Data System (ADS)

Wang, Mingjie; Rudek, Benedikt; Bennett, Daniel; de Vera, Pablo; Bug, Marion; Buhr, Ticia; Baek, Woon Yong; Hilgers, Gerhard; Rabus, Hans

2016-05-01

Double-differential cross sections for ionization of tetrahydrofuran by protons with energies from 300 to 3000 keV were measured at the Physikalisch-Technische Bundesanstalt ion accelerator facility. The electrons emitted at angles between 15∘ and 150∘ relative to the ion-beam direction were detected with an electrostatic hemispherical electron spectrometer. Single-differential and total ionization cross sections have been derived by integration. The experimental results are compared to the semiempirical Hansen-Kocbach-Stolterfoht model as well as to the recently reported method based on the dielectric formalism. The comparison to the latter showed good agreement with experimental data in a broad range of emission angles and energies of secondary electrons. The scaling property of ionization cross sections for tetrahydrofuran was also investigated. Compared to molecules of different size, the ionization cross sections of tetrahydrofuran were found to scale with the number of valence electrons at large impact parameters.

Two-dimensional freezing criteria for crystallizing colloidal monolayers

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

Wang Ziren; Han Yilong; Alsayed, Ahmed M.

Video microscopy was employed to explore crystallization of colloidal monolayers composed of diameter-tunable microgel spheres. Two-dimensional (2D) colloidal liquids were frozen homogenously into polycrystalline solids, and four 2D criteria for freezing were experimentally tested in thermal systems for the first time: the Hansen-Verlet freezing rule, the Loewen-Palberg-Simon dynamical freezing criterion, and two other rules based, respectively, on the split shoulder of the radial distribution function and on the distribution of the shape factor of Voronoi polygons. Importantly, these freezing criteria, usually applied in the context of single crystals, were demonstrated to apply to the formation of polycrystalline solids. At themore » freezing point, we also observed a peak in the fluctuations of the orientational order parameter and a percolation transition associated with caged particles. Speculation about these percolated clusters of caged particles casts light on solidification mechanisms and dynamic heterogeneity in freezing.« less

Experimental determination of spin-dependent electron density by joint refinement of X-ray and polarized neutron diffraction data.

PubMed

Deutsch, Maxime; Claiser, Nicolas; Pillet, Sébastien; Chumakov, Yurii; Becker, Pierre; Gillet, Jean Michel; Gillon, Béatrice; Lecomte, Claude; Souhassou, Mohamed

2012-11-01

New crystallographic tools were developed to access a more precise description of the spin-dependent electron density of magnetic crystals. The method combines experimental information coming from high-resolution X-ray diffraction (XRD) and polarized neutron diffraction (PND) in a unified model. A new algorithm that allows for a simultaneous refinement of the charge- and spin-density parameters against XRD and PND data is described. The resulting software MOLLYNX is based on the well known Hansen-Coppens multipolar model, and makes it possible to differentiate the electron spins. This algorithm is validated and demonstrated with a molecular crystal formed by a bimetallic chain, MnCu(pba)(H(2)O)(3)·2H(2)O, for which XRD and PND data are available. The joint refinement provides a more detailed description of the spin density than the refinement from PND data alone.

Solubilities of selected organic electronic materials in pressurized hot water and estimations of aqueous solubilities at 298.15 K.

PubMed

Karásek, Pavel; Hohnová, Barbora; Planeta, Josef; Št'avíková, Lenka; Roth, Michal

2013-02-01

Increasing production and disposal of organic light-emitting diode (OLED) displays for smartphones and tablets may have impact on the environment depending on the aqueous solubility of the pertinent chemicals. Here, aqueous solubilities are presented for several compounds, mostly aromatic amines, used as hole transport materials in the OLED displays. Solute selection includes 1,4-bis(diphenylamino)benzene, tetra-N-phenylbenzidine, 4,4'-bis(N-carbazolyl)-1,1'-biphenyl, 1,3,5-tris(diphenylamino)benzene, and 9,10-bis(phenylethynyl)anthracene. The solubilities are those in pressurized hot water (PHW), i.e., measured at elevated temperature (up to 260 °C) and pressure. The semi-quantitative estimates of room-temperature solubilities of the solutes have been obtained from extrapolations of the solubilities in PHW. For the compounds studied, the estimated aqueous solubilities at room temperature do not exceed 2×10(-11) g of the solute per 1 kg of water. Aqueous solubilities of triphenylamine have also been measured and used to upgrade a recent group-contribution model of aqueous solubilities of organic nonelectrolytes with the parameters for the nitrogen atom in aromatic amines. Copyright © 2012 Elsevier Ltd. All rights reserved.

Nutritional quality of eggs from hens fed distillers dried grains with solubles

USDA-ARS?s Scientific Manuscript database

A feeding trial was conducted with laying hens where either 10% or 20% regular-fat distiller’s dried grains with solubles (R-DDGS) or low-fat DDGS (L-DDGS) were incorporated into the feed. Production parameters and the effect of DDGS on egg nutritional quality, focusing on yolk lipids, were evaluate...

Modeling the Hydrogen Solubility in Liquid Aluminum Alloys

NASA Astrophysics Data System (ADS)

Harvey, Jean-Philippe; Chartrand, Patrice

2010-08-01

The modeling of hydrogen solubility in multicomponent Al-(Li, Mg, Cu, and Si) liquid phase has been performed with a thermodynamic approach using the modified quasichemical model with the pair approximation (MQMPA). All hydrogen solubility data available in literature was assessed critically to obtain the binary parameters of the MQMPA model for the Al-H, Li-H, Mg-H, Cu-H, Zn-H, and Si-H melts. For the Li-H system, a new thermodynamic description of the stable solid lithium hydride was determined based on the c p found in literature. The thermodynamic model for the Al-Li system also was reassessed in this work to take into account the short-range ordering observed for this system. Built-in interpolation techniques allow the model to estimate the thermodynamic properties of the multicomponent liquid solution from the liquid model parameters of the lower order subsystems. A comparison of the calculated hydrogen solubility performed at various equilibrium conditions of temperature, pressure, and composition with the available experimental data found in the literature is presented in this work, as well as a comparison with some results from previous modeling.

Solubility Prediction of Active Pharmaceutical Compounds with the UNIFAC Model

NASA Astrophysics Data System (ADS)

Nouar, Abderrahim; Benmessaoud, Ibtissem; Koutchoukali, Ouahiba; Koutchoukali, Mohamed Salah

2016-03-01

The crystallization from solution of an active pharmaceutical ingredient requires the knowledge of the solubility in the entire temperature range investigated during the process. However, during the development of a new active ingredient, these data are missing. Its experimental determination is possible, but tedious. UNIFAC Group contribution method Fredenslund et al. (Vapor-liquid equilibria using UNIFAC: a group contribution method, 1977; AIChE J 21:1086, 1975) can be used to predict this physical property. Several modifications on this model have been proposed since its development in 1977, modified UNIFAC of Dortmund Weidlich et al. (Ind Eng Chem Res 26:1372, 1987), Gmehling et al. (Ind Eng Chem Res 32:178, 1993), Pharma-modified UNIFAC Diedrichs et al. (Evaluation und Erweiterung thermodynamischer Modelle zur Vorhersage von Wirkstofflöslichkeiten, PhD Thesis, 2010), KT-UNIFAC Kang et al. (Ind Eng Chem Res 41:3260, 2002), ldots In this study, we used UNIFAC model by considering the linear temperature dependence of interaction parameters as in Pharma-modified UNIFAC and structural groups as defined by KT-UNIFAC first-order model. More than 100 binary datasets were involved in the estimation of interaction parameters. These new parameters were then used to calculate activity coefficient and solubility of some molecules in various solvents at different temperatures. The model gives better results than those from the original UNIFAC and shows good agreement between the experimental solubility and the calculated one.

Match of Solubility Parameters Between Oil and Surfactants as a Rational Approach for the Formulation of Microemulsion with a High Dispersed Volume of Copaiba Oil and Low Surfactant Content.

PubMed

Xavier-Junior, Francisco Humberto; Huang, Nicolas; Vachon, Jean-Jacques; Rehder, Vera Lucia Garcia; do Egito, Eryvaldo Sócrates Tabosa; Vauthier, Christine

2016-12-01

Aim was to formulate oil-in-water (O/W) microemulsion with a high volume ratio of complex natural oil, i.e. copaiba oil and low surfactant content. The strategy of formulation was based on (i) the selection of surfactants based on predictive calculations of chemical compatibility between their hydrophobic moiety and oil components and (ii) matching the HLB of the surfactants with the required HLB of the oil. Solubility parameters of the hydrophobic moiety of the surfactants and of the main components found in the oil were calculated and compared. In turn, required HLB of oils were calculated. Selection of surfactants was achieved matching their solubility parameters with those of oil components. Blends of surfactants were prepared with HLB matching the required HLB of the oils. Oil:water mixtures (15:85 and 25:75) were the titrated with surfactant blends until a microemulsion was formed. Two surfactant blends were identified from the predictive calculation approach. Microemulsions containing up to 19.6% and 13.7% of selected surfactant blends were obtained. O/W microemulsions with a high volume fraction of complex natural oil and a reasonable surfactant concentration were formulated. These microemulsions can be proposed as delivery systems for the oral administration of poorly soluble drugs.

Binary classification of aqueous solubility using support vector machines with reduction and recombination feature selection.

PubMed

Cheng, Tiejun; Li, Qingliang; Wang, Yanli; Bryant, Stephen H

2011-02-28

Aqueous solubility is recognized as a critical parameter in both the early- and late-stage drug discovery. Therefore, in silico modeling of solubility has attracted extensive interests in recent years. Most previous studies have been limited in using relatively small data sets with limited diversity, which in turn limits the predictability of derived models. In this work, we present a support vector machines model for the binary classification of solubility by taking advantage of the largest known public data set that contains over 46 000 compounds with experimental solubility. Our model was optimized in combination with a reduction and recombination feature selection strategy. The best model demonstrated robust performance in both cross-validation and prediction of two independent test sets, indicating it could be a practical tool to select soluble compounds for screening, purchasing, and synthesizing. Moreover, our work may be used for comparative evaluation of solubility classification studies ascribe to the use of completely public resources.

Sibutramine characterization and solubility, a theoretical study

NASA Astrophysics Data System (ADS)

Aceves-Hernández, Juan M.; Nicolás Vázquez, Inés; Hinojosa-Torres, Jaime; Penieres Carrillo, Guillermo; Arroyo Razo, Gabriel; Miranda Ruvalcaba, René

2013-04-01

Solubility data from sibutramine (SBA) in a family of alcohols were obtained at different temperatures. Sibutramine was characterized by using thermal analysis and X-ray diffraction technique. Solubility data were obtained by the saturation method. The van't Hoff equation was used to obtain the theoretical solubility values and the ideal solvent activity coefficient. No polymorphic phenomena were found from the X-ray diffraction analysis, even though this compound is a racemic mixture of (+) and (-) enantiomers. Theoretical calculations showed that the polarisable continuum model was able to reproduce the solubility and stability of sibutramine molecule in gas phase, water and a family of alcohols at B3LYP/6-311++G (d,p) level of theory. Dielectric constant, dipolar moment and solubility in water values as physical parameters were used in those theoretical calculations for explaining that behavior. Experimental and theoretical results were compared and good agreement was obtained. Sibutramine solubility increased from methanol to 1-octanol in theoretical and experimental results.

Optimized Unlike-Pair Interactions for Water-Carbon Dioxide Mixtures described by the SPC/E and EPM2 Models

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

Vlcek, Lukas; Chialvo, Ariel A; Cole, David

The unlike- pair interaction parameters for the SPC/E- EPM2 models have been optimized to reproduce the mutual solubility of water and carbon dioxide at the conditions of liquid- supercritical fluid phase equilibria. An efficient global optimization of the parameters is achieved through an implementation of the coupling parameter approach, adapted to phase equilibria calculations in the Gibbs ensemble, that explicitly corrects for the over- polarization of the SPC/E water molecule in the non- polar CO2 environments. The resulting H2O- CO2 force field reproduces accurately the available experimental solubilities at the two fluid phases in equilibria as well as the correspondingmore » species tracer diffusion coefficients.« less

Detecting ordered small molecule drug aggregates in live macrophages: a multi-parameter microscope image data acquisition and analysis strategy

PubMed Central

Rzeczycki, Phillip; Yoon, Gi Sang; Keswani, Rahul K.; Sud, Sudha; Stringer, Kathleen A.; Rosania, Gus R.

2017-01-01

Following prolonged administration, certain orally bioavailable but poorly soluble small molecule drugs are prone to precipitate out and form crystal-like drug inclusions (CLDIs) within the cells of living organisms. In this research, we present a quantitative multi-parameter imaging platform for measuring the fluorescence and polarization diattenuation signals of cells harboring intracellular CLDIs. To validate the imaging system, the FDA-approved drug clofazimine (CFZ) was used as a model compound. Our results demonstrated that a quantitative multi-parameter microscopy image analysis platform can be used to study drug sequestering macrophages, and to detect the formation of ordered molecular aggregates formed by poorly soluble small molecule drugs in animals. PMID:28270989

Detecting ordered small molecule drug aggregates in live macrophages: a multi-parameter microscope image data acquisition and analysis strategy.

PubMed

Rzeczycki, Phillip; Yoon, Gi Sang; Keswani, Rahul K; Sud, Sudha; Stringer, Kathleen A; Rosania, Gus R

2017-02-01

Following prolonged administration, certain orally bioavailable but poorly soluble small molecule drugs are prone to precipitate out and form crystal-like drug inclusions (CLDIs) within the cells of living organisms. In this research, we present a quantitative multi-parameter imaging platform for measuring the fluorescence and polarization diattenuation signals of cells harboring intracellular CLDIs. To validate the imaging system, the FDA-approved drug clofazimine (CFZ) was used as a model compound. Our results demonstrated that a quantitative multi-parameter microscopy image analysis platform can be used to study drug sequestering macrophages, and to detect the formation of ordered molecular aggregates formed by poorly soluble small molecule drugs in animals.

Methods for calculation of engineering parameters for gas separation. [vapor pressure and solubility of gases in organic liquids

NASA Technical Reports Server (NTRS)

Lawson, D. D.

1979-01-01

A group additivity method is generated which allows estimation, from the structural formulas alone, of the energy of vaporization and the molar volume at 25 C of many nonpolar organic liquids. Using these two parameters and appropriate thermodynamic relations, the vapor pressure of the liquid phase and the solubility of various gases in nonpolar organic liquids are predicted. It is also possible to use the data to evaluate organic and some inorganic liquids for use in gas separation stages or liquids as heat exchange fluids in prospective thermochemical cycles for hydrogen production.

Effect of grain moisture content during milling on pasting profile and functional properties of amaranth fractions.

PubMed

Kumar, K Vishnuswamy Preetham; Dharmaraj, Usha; Sakhare, Suresh D; Inamdar, Aashitosh A

2016-05-01

Evaluation of functional properties of milled fractions of grain amaranth may be useful to decide the end uses of the grain. Hence, pasting profiles of amaranth fractions obtained by milling the grains at different moisture contents were studied in relation with their starch profile and also with their swelling power and solubility indices. It was observed that, for flour fraction, the viscosity parameters were lowest at 14-16 % moisture content. Swelling power and solubility indices of the samples varied as a function of grain moisture content. The middling fraction also showed similar pasting pattern with the variation of grain moisture content. The seed coat fractions showed higher gelatinization temperature compared to that of fine flour and middling fractions. However, starch content of the fine seed coat fraction was comparable with that of the flour and middling fractions. The coarse seed coat fraction showed lower viscosity parameters than the other samples. Viscosity parameters correlated well among themselves while, they did not show significant correlation with the starch content. However, the viscosity parameters showed negative correlation with the soluble amylose content. The study revealed that, the fractions obtained by milling the grains at different moisture content show differential pasting profiles and functional properties.

The solubility-permeability interplay and its implications in formulation design and development for poorly soluble drugs.

PubMed

Dahan, Arik; Miller, Jonathan M

2012-06-01

While each of the two key parameters of oral drug absorption, the solubility and the permeability, has been comprehensively studied separately, the relationship and interplay between the two have been largely ignored. For instance, when formulating a low-solubility drug using various solubilization techniques: what are we doing to the apparent permeability when we increase the solubility? Permeability is equal to the drug's diffusion coefficient through the membrane times the membrane/aqueous partition coefficient divided by the membrane thickness. The direct correlation between the intestinal permeability and the membrane/aqueous partitioning, which in turn is dependent on the drug's apparent solubility in the GI milieu, suggests that the solubility and the permeability are closely associated, exhibiting a certain interplay between them, and the current view of treating the one irrespectively of the other may not be sufficient. In this paper, we describe the research that has been done thus far, and present new data, to shed light on this solubility-permeability interplay. It has been shown that decreased apparent permeability accompanies the solubility increase when using different solubilization methods. Overall, the weight of the evidence indicates that the solubility-permeability interplay cannot be ignored when using solubility-enabling formulations; looking solely at the solubility enhancement that the formulation enables may be misleading with regards to predicting the resulting absorption, and hence, the solubility-permeability interplay must be taken into account to strike the optimal solubility-permeability balance, in order to maximize the overall absorption.

Influences of external vs. core-shell mixing on aerosol optical properties at various relative humidities.

PubMed

Ramachandran, S; Srivastava, Rohit

2013-05-01

Aerosol optical properties of external and core-shell mixtures of aerosol species present in the atmosphere are calculated in this study for different relative humidities. Core-shell Mie calculations are performed using the values of radii, refractive indices and densities of aerosol species that act as core and shell, and the core-shell radius ratio. The single scattering albedo (SSA) is higher when the absorbing species (black carbon, BC) is the core, while for a sulfate core SSA does not vary significantly as the BC in the shell dominates the absorption. Absorption gets enhanced in core-shell mixing of absorbing and scattering aerosols when compared to their external mixture. Thus, SSA is significantly lower for a core-shell mixture than their external mixture. SSA is more sensitive to core-shell ratio than mode radius when BC is the core. The extinction coefficient, SSA and asymmetry parameter are higher for external mixing when compared to BC (core)-water soluble aerosol (shell), and water soluble aerosol (core)-BC (shell) mixtures in the relative humidity range of 0 to 90%. Spectral SSA exhibits the behaviour of the species which acts as a shell in core-shell mixing. The asymmetry parameter for an external mixture of water soluble aerosol and BC is higher than BC (core)-water soluble aerosol (shell) mixing and increases as function of relative humidity. The asymmetry parameter for the water soluble aerosol (core)-BC (shell) is independent of relative humidity as BC is hydrophobic. The asymmetry parameter of the core-shell mixture decreases when BC aerosols are involved in mixing, as the asymmetry parameter of BC is lower. Aerosol optical depth (AOD) of core-shell mixtures increases at a higher rate when the relative humidity exceeds 70% in continental clean and urban aerosol models, whereas AOD remains the same when the relative humidity exceeds 50% in maritime aerosol models. The SSA for continental aerosols varies for core-shell mixing of water soluble aerosol (core)-shell (BC) when compared to their external mixture, while the SSA for maritime aerosols does not vary significantly for different mixing scenarios because of the dominance of sea salt aerosols. Thus, these results confirm that aerosol mixing can modify the physical and optical characteristics of aerosols, which vary as a function of relative humidity. These calculations will be useful in parameterising the effect of core-shell vs. external mixing of aerosols in global climate models, and in the evaluation of aerosol radiative effects.

76 FR 20994 - Privacy Act of 1974; Deletion of an Existing System of Records

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-14

... for review at this location, by appointment, during regular business hours, Monday through Friday from... hospital space where the elderly Hansen's disease resident patients resided. The purpose of this System of...

76 FR 77247 - Lewis and Clark National Wildlife Refuge and Julia Butler Hansen Refuge for the Columbian White...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-12

... wilderness designation proposal, and work with partners to ensure that dredge-spoil islands provide benefits..., studying potential wilderness lands, developing a bicycling and hiking trail, installing interpretive...

Pilot in Rendezvous Docking Simulator

NASA Image and Video Library

1962-12-19

Unidentified Pilot eyeballs his way to a docking by peering through the portal in his capsule. Photo published in Spaceflight Revolution, NASA Langley Research Center From Sputnik to Apollo. By James R. Hansen. NASA SP-4308, 1995, p. 372.

Phytophthora austrocedrae.

Treesearch

A. Greslebin; E. M. Hansen; L. La Manna

2011-01-01

Phytophthora austrocedrae Gresl. & E.M. Hansen (2007) was isolated from necrotic lesions of stem and roots of Austrocedrus chilensis (Cupressaceae). It is homothallic with semi-papillate sporangia, oogonia with amphigynous antheridia, and very slow growth. It is the cause of "mal del...

Equations for O2 and CO2 solubilities in saline and plasma: combining temperature and density dependences.

PubMed

Christmas, Kevin M; Bassingthwaighte, James B

2017-05-01

Solubilities of respiratory gasses in water, saline, and plasma decrease with rising temperatures and solute concentrations. Henry's Law, C = α·P, states that the equilibrium concentration of a dissolved gas is solubility times partial pressure. Solubilities in the water of a solution depend on temperature and the content of other solutes. Blood temperatures may differ more than 20°C between skin and heart, and an erythrocyte will undergo that range as blood circulates. The concentrations of O 2 and CO 2 are the driving forces for diffusion, exchanges, and for reactions. We provide an equation for O 2 and CO 2 solubilities, α, that allows for continuous changes in temperature, T, and solution density, ρ, in dynamically changing states:[Formula: see text]This two-exponential expression with a density scalar γ, and a density exponent β, accounts for solubility changes due to density changes of an aqueous solution. It fits experimental data on solubilities in water, saline, and plasma over temperatures from 20 to 40°C, and for plasma densities, ρ sol up to 1.020 g/ml with ~0.3% error. The amounts of additional bound O 2 (to Hb) and CO 2 (bicarbonate and carbamino) depend on the concentrations in the local water space and the reaction parameters. During exercise, solubility changes are large; both ρ sol and T change rapidly with spatial position and with time. In exercise hemoconcentration plasma, ρ sol exceeds 1.02, whereas T may range over 20°C. The six parameters for O 2 and the six for CO 2 are constants, so solubilities are calculable continuously as T and ρ sol change. NEW & NOTEWORTHY Solubilities for oxygen and carbon dioxide are dependent on the density of the solution, on temperature, and on the partial pressure. We provide a brief equation suitable for hand calculators or mathematical modeling, accounting for these factors over a wide range of temperatures and solution densities for use in rapidly changing conditions, such as extreme exercise or osmotic transients, with better than 0.5% accuracy. Copyright © 2017 the American Physiological Society.

Leprosy and rheumatoid arthritis: consequence or association?

PubMed

Henriques, Celia Coelho; Lopéz, Begoña; Mestre, Tiago; Grima, Bruno; Panarra, António; Riso, Nuno

2012-08-13

Leprosy or Hansen's disease is a chronic granulomatous infectious disease caused by Mycobacterium leprae with a high prevalence in some developing countries however, it is rarely seen in non-endemic regions. Arthritis has been described in all types of Hansen's disease. Chronic arthritis is known to exist even in paucibacillary forms, resolved or treated disease and in patients without reaction, suggesting a perpetuated inflammatory process. In these cases leprosy can mimic some autoimmune diseases such as rheumatoid arthritis. When a patient with a history of leprosy presents with a symmetric, distal, polyarthritis the diagnosis may not be linear. Possibly it is a rheumatoid-like leprous arthritis with M leprae acting as the trigger element for the chronic process or it is an overlap condition, with a concomitant rheumatoid arthritis? A case report of a patient with a chronic inflammatory arthritis with 10 years of evolution is presented. The differential diagnosis between leprous and rheumatoid arthritis is discussed.

On the error in the nucleus-centered multipolar expansion of molecular electron density and its topology: A direct-space computational study.

PubMed

Michael, J Robert; Koritsanszky, Tibor

2017-05-28

The convergence of nucleus-centered multipolar expansion of the quantum-chemical electron density (QC-ED), gradient, and Laplacian is investigated in terms of numerical radial functions derived by projecting stockholder atoms onto real spherical harmonics at each center. The partial sums of this exact one-center expansion are compared with the corresponding Hansen-Coppens pseudoatom (HC-PA) formalism [Hansen, N. K. and Coppens, P., "Testing aspherical atom refinements on small-molecule data sets," Acta Crystallogr., Sect. A 34, 909-921 (1978)] commonly utilized in experimental electron density studies. It is found that the latter model, due to its inadequate radial part, lacks pointwise convergence and fails to reproduce the local topology of the target QC-ED even at a high-order expansion. The significance of the quantitative agreement often found between HC-PA-based (quadrupolar-level) experimental and extended-basis QC-EDs can thus be challenged.

NASA GISS Surface Temperature (GISTEMP) Analysis

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

Schmidt, G.; Ruedy, R.; Persin, A

The NASA GISS Surface Temperature (GISTEMP) analysis provides a measure of the changing global surface temperature with monthly resolution for the period since 1880, when a reasonably global distribution of meteorological stations was established. The input data that the GISTEMP Team use for the analysis, collected by many national meteorological services around the world, are the adjusted data of the Global Historical Climatology Network (GHCN) Vs. 3 (this represents a change from prior use of unadjusted Vs. 2 data) (Peterson and Vose, 1997 and 1998), United States Historical Climatology Network (USHCN) data, and SCAR (Scientific Committee on Antarctic Research) datamore » from Antarctic stations. Documentation of the basic analysis method is provided by Hansen et al. (1999), with several modifications described by Hansen et al. (2001). The GISS analysis is updated monthly, however CDIAC's presentation of the data here is updated annually.« less

A simple and accurate method for calculation of the structure factor of interacting charged spheres.

PubMed

Wu, Chu; Chan, Derek Y C; Tabor, Rico F

2014-07-15

Calculation of the structure factor of a system of interacting charged spheres based on the Ginoza solution of the Ornstein-Zernike equation has been developed and implemented on a stand-alone spreadsheet. This facilitates direct interactive numerical and graphical comparisons between experimental structure factors with the pioneering theoretical model of Hayter-Penfold that uses the Hansen-Hayter renormalisation correction. The method is used to fit example experimental structure factors obtained from the small-angle neutron scattering of a well-characterised charged micelle system, demonstrating that this implementation, available in the supplementary information, gives identical results to the Hayter-Penfold-Hansen approach for the structure factor, S(q) and provides direct access to the pair correlation function, g(r). Additionally, the intermediate calculations and outputs can be readily accessed and modified within the familiar spreadsheet environment, along with information on the normalisation procedure. Copyright © 2014 Elsevier Inc. All rights reserved.

Cutting Through Multiyear Ice

NASA Image and Video Library

2012-06-07

ICESCAPE scientists watched from the deck of the Healy as it cut a path through thick multiyear ice on July 6, 2011. Cutting the path is key for getting researchers to remote research sites amid the sea ice. Credit: NASA/Kathryn Hansen The ICESCAPE mission, or "Impacts of Climate on Ecosystems and Chemistry of the Arctic Pacific Environment," is a NASA shipborne investigation to study how changing conditions in the Arctic affect the ocean's chemistry and ecosystems. The bulk of the research took place in the Beaufort and Chukchi seas in summer 2010 and 2011. Credit: NASA/Kathryn Hansen NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

On the error in the nucleus-centered multipolar expansion of molecular electron density and its topology: A direct-space computational study

NASA Astrophysics Data System (ADS)

Michael, J. Robert; Koritsanszky, Tibor

2017-05-01

The convergence of nucleus-centered multipolar expansion of the quantum-chemical electron density (QC-ED), gradient, and Laplacian is investigated in terms of numerical radial functions derived by projecting stockholder atoms onto real spherical harmonics at each center. The partial sums of this exact one-center expansion are compared with the corresponding Hansen-Coppens pseudoatom (HC-PA) formalism [Hansen, N. K. and Coppens, P., "Testing aspherical atom refinements on small-molecule data sets," Acta Crystallogr., Sect. A 34, 909-921 (1978)] commonly utilized in experimental electron density studies. It is found that the latter model, due to its inadequate radial part, lacks pointwise convergence and fails to reproduce the local topology of the target QC-ED even at a high-order expansion. The significance of the quantitative agreement often found between HC-PA-based (quadrupolar-level) experimental and extended-basis QC-EDs can thus be challenged.

Gels of ferulated arabinoxylans extracted from distillers dried grains with solubles: rheology, structural parameters and microstructure

USDA-ARS?s Scientific Manuscript database

One of the major by-products of bioethanol production is distillers dried grains with solubles (DDGS). Maize is one of the main sources for the production of this biofuel. In this way, dietary fiber represents the principal fraction of DDGS, which could be a potential source of added-value biomolecu...

Solubility and dissolution thermodynamics of phthalic anhydride in organic solvents at 283-313 K

NASA Astrophysics Data System (ADS)

Wang, Long; Zhang, Fang; Gao, Xiaoqiang; Luo, Tingliang; Xu, Li; Liu, Guoji

2017-08-01

The solubility of phthalic anhydride was measured at 283-313 K under atmospheric pressure in ethyl acetate, n-propyl acetate, methyl acetate, acetone, 1,4-dioxane, n-hexane, n-butyl acetate, cyclohexane, and dichloromethane. The solubility of phthalic anhydride in all solvents increased with the increasing temperature. The Van't Hoff equation, modified Apelblat equation, λ h equation, and Wilson model were used to correlate the experimental solubility data. The standard dissolution enthalpy, the standard entropy, and the standard Gibbs energy were evaluated based on the Van't Hoff analysis. The experimental data and model parameters would be useful for optimizing of the separation processes involving phthalic anhydride.

Estimating the physicochemical properties of polyhalogenated aromatic and aliphatic compounds using UPPER: part 2. Aqueous solubility, octanol solubility and octanol-water partition coefficient.

PubMed

Admire, Brittany; Lian, Bo; Yalkowsky, Samuel H

2015-01-01

The UPPER (Unified Physicochemical Property Estimation Relationships) model uses additive and non-additive parameters to estimate 20 biologically relevant properties of organic compounds. The model has been validated by Lian and Yalkowsky (2014) on a data set of 700 hydrocarbons. Recently, Admire et al. (2014) expanded the model to predict the boiling and melting points of 1288 polyhalogenated benzenes, biphenyls, dibenzo-p-dioxins, diphenyl ethers, anisoles and alkanes. In this work, 19 new group descriptors are determined and used to predict the aqueous solubilities, octanol solubilities and the octanol-water coefficients. Copyright © 2014 Elsevier Ltd. All rights reserved.

Raman correlation spectroscopy: A feasibility study of a new optical correlation technique and development of multi-component nanoparticles using the reprecipitation method

NASA Astrophysics Data System (ADS)

Nishida, Maki

The feasibility of Raman correlation spectroscopy (RCS) is investigated as a new temporal optical fluctuation spectroscopy in this dissertation. RCS analyzes the correlations of the intensity fluctuations of Raman scattering from particles in a suspension that undergo Brownian motion. Because each Raman emission line arises from a specific molecular bond, the RCS method could yield diffusion behavior of specific chemical species within a dispersion. Due to the nature of Raman scattering as a coherent process, RCS could provide similar information as acquired in dynamic light scattering (DLS) and be practical for various applications that requires the chemical specificity in dynamical information. The theoretical development is discussed, and four experimental implementations of this technique are explained. The autocorrelation of the intensity fluctuations from a beta-carotene solution is obtained using the some configurations; however, the difficulty in precise alignment and weak nature of Raman scattering prevented the achievement of high sensitivity and resolution. Possible fluctuations of the phase of Raman scattering could also be affecting the results. A possible explanation of the observed autocorrelation in terms of number fluctuations of particles is also examined to test the feasibility of RCS as a new optical characterization method. In order to investigate the complex systems for which RCS would be useful, strategies for the creation of a multicomponent nanoparticle system are also explored. Using regular solution theory along with the concept of Hansen solubility parameters, an analytical model is developed to predict whether two or more components will form single nanoparticles, and what effect various processing conditions would have. The reprecipitation method was used to demonstrate the formation of the multi-component system of the charge transfer complex perylene:TCNQ (tetracyanoquinodimethane) and the active pharmaceutical ingredient cocrystal of CBZ:NCT (carbamazepine:nicotinamide). The experimental results with various characterization methods including DLS, absorption spectroscopy, powder x-ray diffraction, and SEM imaging, verify formation of the multicomponent cocrystals. The observation of the self-assembly of TCNQ crystals is also discussed.

Construction of drug-polymer thermodynamic phase diagrams using Flory-Huggins interaction theory: identifying the relevance of temperature and drug weight fraction to phase separation within solid dispersions.

PubMed

Tian, Yiwei; Booth, Jonathan; Meehan, Elizabeth; Jones, David S; Li, Shu; Andrews, Gavin P

2013-01-07

Amorphous drug-polymer solid dispersions have the potential to enhance the dissolution performance and thus bioavailability of BCS class II drug compounds. The principle drawback of this approach is the limited physical stability of amorphous drug within the dispersion. Accurate determination of the solubility and miscibility of drug in the polymer matrix is the key to the successful design and development of such systems. In this paper, we propose a novel method, based on Flory-Huggins theory, to predict and compare the solubility and miscibility of drug in polymeric systems. The systems chosen for this study are (1) hydroxypropyl methylcellulose acetate succinate HF grade (HPMCAS-HF)-felodipine (FD) and (2) Soluplus (a graft copolymer of polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol)-FD. Samples containing different drug compositions were mixed, ball milled, and then analyzed by differential scanning calorimetry (DSC). The value of the drug-polymer interaction parameter χ was calculated from the crystalline drug melting depression data and extrapolated to lower temperatures. The interaction parameter χ was also calculated at 25 °C for both systems using the van Krevelen solubility parameter method. The rank order of interaction parameters of the two systems obtained at this temperature was comparable. Diagrams of drug-polymer temperature-composition and free energy of mixing (ΔG(mix)) were constructed for both systems. The maximum crystalline drug solubility and amorphous drug miscibility may be predicted based on the phase diagrams. Hyper-DSC was used to assess the validity of constructed phase diagrams by annealing solid dispersions at specific drug loadings. Three different samples for each polymer were selected to represent different regions within the phase diagram.

Hansen's Disease and Rheumatoid Arthritis Crossover of Clinical Symptoms: A Case Series of 18 Patients in the United States.

PubMed

Labuda, Sarah M; Schieffelin, John S; Shaffer, Jeffrey G; Stryjewska, Barbara M

2017-12-01

Hansen's Disease (HD) is a rare, chronic granulomatous infection of the skin and peripheral nerves caused by the noncultivable organism Mycobacterium leprae . Arthritis is the third most common symptom of HD. Subjects with both confirmed HD on skin biopsy and chronic arthritis were identified at the National Hansen's Disease Program (NHDP). We conducted a series of medical chart reviews and extracted and logged personally deidentified data into a database and carried out descriptive analyses. Eighteen of 261 subjects presented to the NDHP with both HD and chronic arthritis between 2001 and 2015. Among these, 16 were male, 16 were white, and 15 were residents of Louisiana. The median age at diagnosis of HD was 67 years. Ten of these subjects were diagnosed with borderline lepromatous leprosy, seven were diagnosed with lepromatous, and one was diagnosed with borderline tuberculoid leprosy. Patients were symptomatic with arthritis for a median of 5.3 years before HD diagnosis. Sixty-two percent of patients (11) were diagnosed with rheumatoid arthritis (RA) before HD diagnosis, and 10 of which were seronegative RA. Hands, feet, wrists, and elbows were most commonly reported as affected joints. Over half of the patients (61%) had completed HD multidrug therapy at the time of review, and 73% of these subjects had persistent joint pain requiring steroids or methotrexate for symptomatic control. Chronic arthritis in HD patients is present in a series of US-acquired cases of HD. Arthritis did not resolve with successful treatment of HD in most cases.

Formulation of thermoresponsive and buccal adhesive in situ gel for treatment of oral thrush containing poorly water soluble drug bifonazole.

PubMed

Patel, Dimendra; Patel, Dipti; Prajapati, Jatin; Patel, Umang; Patel, Vijay

2012-03-01

The aim of the present work is to formulate and evaluate in situ oral topical gels of poorly water soluble drug Bifonazole based on temperature induced systems for the treatment of oral candidiasis. Bifonazole is poorly water soluble and low permeable drug means it's belongs to BCS Class IV. Due to its poor water solubility, it necessary to enhance solubility in water by make complex with Beta- Cyclodextrin (Drug to βCyclo Dextrine ratio is 1:1). After in situ gel preparation done by using Poloxamer (10% and 15%w/w) along with carbopol 934 (0.2 to 1.0% w/w) and Bifonazole - β CD complex (1%w/w). The formulations were evaluated for physiochemical parameter, gelation Temperature, viscosity, gel strength, content uniformity mucoadhesive force, Diffusion Study.

Formulation of thermoresponsive and buccal adhesive in situ gel for treatment of oral thrush containing poorly water soluble drug bifonazole

PubMed Central

Patel, Dimendra; Patel, Dipti; Prajapati, Jatin; Patel, Umang; Patel, Vijay

2012-01-01

The aim of the present work is to formulate and evaluate in situ oral topical gels of poorly water soluble drug Bifonazole based on temperature induced systems for the treatment of oral candidiasis. Bifonazole is poorly water soluble and low permeable drug means it's belongs to BCS Class IV. Due to its poor water solubility, it necessary to enhance solubility in water by make complex with Beta- Cyclodextrin (Drug to βCyclo Dextrine ratio is 1:1). After in situ gel preparation done by using Poloxamer (10% and 15%w/w) along with carbopol 934 (0.2 to 1.0% w/w) and Bifonazole – β CD complex (1%w/w). The formulations were evaluated for physiochemical parameter, gelation Temperature, viscosity, gel strength, content uniformity mucoadhesive force, Diffusion Study. PMID:23066185

Project Apollo Flight Sequence

NASA Image and Video Library

1966-08-01

Lunar Orbiter's "Typical Flight sequence of Events" turned out to be quite typical indeed, as all five spacecraft performed exactly as planned. -- Published in James R. Hansen, Spaceflight Revolution: NASA Langley Research Center From Sputnik to Apollo, (Washington: NASA, 1995), p. 340.

Directory of Federal Contacts on Environmental Protection,

DTIC Science & Technology

1982-01-01

Director D. M. Hannemann 111B 0362 Energy Coordinator D. K. Bain f1IP 0102 Support Services W. E. Elgin 1111 0102 Head, Management Branch E. E. Hoover... Hannemann , D. M................................................. 8 Ilannesslager, R.............................................. ... 76 Hansen, A.J

Estimates of genetic parameters for chemical traits of meat quality in Japanese black cattle

PubMed Central

Sakuma, Hironori; Saito, Kaoru; Kohira, Kimiko; Ohhashi, Fumie; Shoji, Noriaki

2016-01-01

Abstract Genetic parameters for 54 carcass and chemical traits, such as general composition (moisture, crude fat and crude protein), fatty acid composition and water‐soluble compounds (free amino acids, peptides, nucleotides and sugars) of 587 commercial Japanese Black cattle were assessed. Heritability estimates for carcass traits and general composition ranged between 0.19–0.28, whereas those for fatty acid composition ranged between 0.11–0.85. Most heritability estimates for water‐soluble compounds were lower than 0.30; these traits were affected by aging period. Moderate heritability was observed for glutamine, alanine, taurine, anserine, inosine 5′‐monophosphate (IMP), inosine and myo‐inositol. In particular, heritability estimates were the highest (0.66) for taurine. Traits with moderate heritability were unaffected by aging period, with the exception of IMP, which was affected by aging period but exhibited moderate heritability (0.47). Although phenotypic correlations of water‐soluble compounds with carcass weight (CW), beef marbling standard (BMS) and monounsaturated fatty acid were generally low, genetic correlations between these traits were low to high. At the genetic level, most of the water‐soluble compounds were positively correlated with monounsaturated fatty acid but negatively correlated with CW and BMS. Thus, our results indicate that genetic variance and correlations could exist and be captured for some of the water‐soluble compounds. PMID:27146072

High-Resolution Modelling of Health Impacts from Air Pollution for Denmark using the Integrated Model System EVA

NASA Astrophysics Data System (ADS)

Brandt, Jørgen; Andersen, Mikael S.; Bønløkke, Jakob; Christensen, Jesper H.; Hansen, Kaj M.; Hertel, Ole; Im, Ulas; Jensen, Steen S.; Ketzel, Matthias; Nielsen, Ole-Kenneth; Plejdrup, Marlene S.; Sigsgaard, Torben; Geels, Camilla

2015-04-01

We have developed an integrated health impact assessment system EVA (Economic Valuation of Air pollution; Brandt et al., 2013a; 2013b), based on the impact-pathway chain, to assess the health impacts and health-related economic externalities of air pollution resulting from specific emission sources or sectors. The system is used to support policymaking with respect to emission control. The EVA system has previously been used to assess the health impacts based on results from a regional model DEHM (the Danish Eulerian Hemispheric Model; Brandt et al., 2012). In this study we have used a coupling of two chemistry transport models to calculate the air pollution concentration at different scales; the DEHM model to calculate the air pollution levels with a resolution down to 5.6 km x 5.6 km and the UBM model (Urban Background Model ; Berkowicz, 2000; Brandt et al., 2001) to further calculate the air pollution at 1 km x 1 km resolution for Denmark using results from DEHM as boundary conditions. Both the emission data based on the SPREAD model (Plejdrup and Gyldenkærne, 2011) as well as the population density has been represented in the model system with the same high resolution. The new developments of the integrated model system will be presented as well as results for health impacts and related external costs over the years 2006-2014 for Denmark. Furthermore, a sensitivity study of the health impact using coarse and fine resolutions in the model system has been carried out to evaluate the effect of improved description of the geographical population distribution with respect to location of local emissions. References Berkowicz, R., 2000. A Simple Model for Urban Background Pollution. Environmental Monitoring and Assessment, 65, 1/2, 259-267. Brandt, J., J. H. Christensen, L. M. Frohn, F. Palmgren, R. Berkowicz and Z. Zlatev, 2001: "Operational air pollution forecasts from European to local scale". Atmospheric Environment, Vol. 35, Sup. No. 1, pp. S91-S98, 2001 Brandt, J., J. D. Silver, L. M. Frohn, C. Geels, A. Gross, A. B. Hansen, K. M. Hansen, G. B. Hedegaard, C. A. Skjøth, H. Villadsen, A. Zare, and J. H. Christensen, 2012: An integrated model study for Europe and North America using the Danish Eulerian Hemispheric Model with focus on intercontinental transport. Atmospheric Environment, Volume 53, June 2012, pp. 156-176, doi:10.1016/j.atmosenv.2012.01.011 Brandt, J., J. D. Silver, J. H. Christensen, M. S. Andersen, J. Bønløkke, T. Sigsgaard, C. Geels, A. Gross, A. B. Hansen, K. M. Hansen, G. B. Hedegaard, E. Kaas and L. M. Frohn, 2013a: "Contribution from the ten major emission sectors in Europe to the Health-Cost Externalities of Air Pollution using the EVA Model System - an integrated modelling approach". Atmospheric Chemistry and Physics, Vol. 13, pp. 7725-7746, 2013. www.atmos-chem-phys.net/13/7725/2013/, doi:10.5194/acp-13-7725-2013. Brandt, J., J. D. Silver, J. H. Christensen, M. S. Andersen, J. Bønløkke, T. Sigsgaard, C. Geels, A. Gross, A. B. Hansen, K. M. Hansen, G. B. Hedegaard, E. Kaas and L. M. Frohn, 2013b: "Assessment of Past, Present and Future Health-Cost Externalities of Air Pollution in Europe and the contribution from international ship traffic using the EVA Model System". Atmospheric Chemistry and Physics. Vol. 13, pp. 7747-7764, 2013. www.atmos-chem-phys.net/13/7747/2013/. doi:10.5194/acp-13-7747-2013. Plejdrup, M.S., Gyldenkærne, S., 2011. Spatial distribution of pollutants to air - the SPREAD model. NERI Technical Report No. 823.

Efficacy of soluble glycoprotein fraction from Allium sativum purified by size exclusion chromatography on murine Schistosomiasis mansoni.

PubMed

Aly, Ibrahim; Taher, Eman E; El-Sayed, Hoda; Mohammed, Faten A; ELnain, Gehan; Hamad, Rabab S; Bayoumy, Elsayed M

2017-06-01

In this work, the efficiency of crude MeOH extracts and soluble glycoprotein fraction of Allium sativum purified by size-exclusion chromatography (SEC) on parasitological, histopathological and some biochemical parameters in Schistosoma mansoni infected mice were investigated. Animals were infected by tail immersion with 100 cercariae/each mouse and divided into five groups in addition to the normal control. The results revealed a significant decrease in mean worm burden in all treated mice especially in the group treated with soluble glycoprotein fraction of A. sativum as compared to infected non-treated control with the disappearance of female worms. Administration of the studied extracts revealed remarkable amelioration in the levels of all the measured parameters in S. mansoni infected mice. In addition, treatment of mice with crude A. sativum MeOH extract and soluble glycoprotein fraction of A. sativum decreased significantly the activities of studied enzymes as compared to the infected untreated group. The highest degrees of enhancement in pathological changes was observed in the treated one with soluble glycoprotein fraction of A. sativum compared to the infected group represented by small sized, late fibro-cellular granuloma, the decrease in cellular constituents and degenerative changes in eggs. In conclusion, A. sativum treatment had effective schistosomicidal activities, through reduction of worm burden and tissue eggs, especially when it was given in purified glycoprotein fraction. Moreover, the soluble glycoprotein fraction of A. sativum largely modulates both the size and the number of granulomas. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development of a Predictive Model for the Long-Term Stability Assessment of Drug-In-Adhesive Transdermal Films Using Polar Pressure-Sensitive Adhesives as Carrier/Matrix.

PubMed

Chenevas-Paule, Clémence; Wolff, Hans-Michael; Ashton, Mark; Schubert, Martin; Dodou, Kalliopi

2017-05-01

Drug crystallization in transdermal drug delivery systems is a critical quality defect. The impact of drug load and hydration on the physical stability of polar (acrylic) drug-in-adhesive (DIA) films was investigated with the objective to identify predictive formulation parameters with respect to drug solubility and long-term stability. Medicated acrylic films were prepared over a range of drug concentrations below and above saturation solubility and were characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, polarized microscopy, and dynamic vapor sorption (DVS) analysis. Physical stability of medicated films was monitored over 4 months under different storage conditions and was dependent on solubility parameters, Gibbs free energy for drug phase transition from the amorphous to the crystalline state, and relative humidity. DVS data, for assessing H-bonding capacity experimentally, were essential to predict physical stability at different humidities and were used together with Gibbs free energy change and the Hoffman equation to develop a new predictive thermodynamic model to estimate drug solubility and stability in DIA films taking into account relative humidity. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Efficient solubilization of inclusion bodies.

PubMed

Freydell, Esteban J; Ottens, Marcel; Eppink, Michel; van Dedem, Gijs; van der Wielen, Luuk

2007-06-01

The overexpression of recombinant proteins in Escherichia coli leads in most cases to their accumulation in the form of insoluble aggregates referred to as inclusion bodies (IBs). To obtain an active product, the IBs must be solubilized and thereafter the soluble monomeric protein needs to be refolded. In this work we studied the solubilization behavior of a model-protein expressed as IBs at high protein concentrations, using a statistically designed experiment to determine which of the process parameters, or their interaction, have the greatest impact on the amount of soluble protein and the fraction of soluble monomer. The experimental methodology employed pointed out an optimum balance between maximum protein solubility and minimum fraction of soluble aggregates. The optimized conditions solubilized the IBs without the formation of insoluble aggregates; moreover, the fraction of soluble monomer was approximately 75% while the fraction of soluble aggregates was approximately 5%. Overall this approach guarantees a better use of the solubilization reagents, which brings an economical and technical benefit, at both large and lab scale and may be broadly applicable for the production of recombinant proteins.

Model-Based Analysis of Biopharmaceutic Experiments To Improve Mechanistic Oral Absorption Modeling: An Integrated in Vitro in Vivo Extrapolation Perspective Using Ketoconazole as a Model Drug.

PubMed

Pathak, Shriram M; Ruff, Aaron; Kostewicz, Edmund S; Patel, Nikunjkumar; Turner, David B; Jamei, Masoud

2017-12-04

Mechanistic modeling of in vitro data generated from metabolic enzyme systems (viz., liver microsomes, hepatocytes, rCYP enzymes, etc.) facilitates in vitro-in vivo extrapolation (IVIV_E) of metabolic clearance which plays a key role in the successful prediction of clearance in vivo within physiologically-based pharmacokinetic (PBPK) modeling. A similar concept can be applied to solubility and dissolution experiments whereby mechanistic modeling can be used to estimate intrinsic parameters required for mechanistic oral absorption simulation in vivo. However, this approach has not widely been applied within an integrated workflow. We present a stepwise modeling approach where relevant biopharmaceutics parameters for ketoconazole (KTZ) are determined and/or confirmed from the modeling of in vitro experiments before being directly used within a PBPK model. Modeling was applied to various in vitro experiments, namely: (a) aqueous solubility profiles to determine intrinsic solubility, salt limiting solubility factors and to verify pK a ; (b) biorelevant solubility measurements to estimate bile-micelle partition coefficients; (c) fasted state simulated gastric fluid (FaSSGF) dissolution for formulation disintegration profiling; and (d) transfer experiments to estimate supersaturation and precipitation parameters. These parameters were then used within a PBPK model to predict the dissolved and total (i.e., including the precipitated fraction) concentrations of KTZ in the duodenum of a virtual population and compared against observed clinical data. The developed model well characterized the intraluminal dissolution, supersaturation, and precipitation behavior of KTZ. The mean simulated AUC 0-t of the total and dissolved concentrations of KTZ were comparable to (within 2-fold of) the corresponding observed profile. Moreover, the developed PBPK model of KTZ successfully described the impact of supersaturation and precipitation on the systemic plasma concentration profiles of KTZ for 200, 300, and 400 mg doses. These results demonstrate that IVIV_E applied to biopharmaceutical experiments can be used to understand and build confidence in the quality of the input parameters and mechanistic models used for mechanistic oral absorption simulations in vivo, thereby improving the prediction performance of PBPK models. Moreover, this approach can inform the selection and design of in vitro experiments, potentially eliminating redundant experiments and thus helping to reduce the cost and time of drug product development.

Diffusion and solubility coefficients determined by permeation and immersion experiments for organic solvents in HDPE geomembrane.

PubMed

Chao, Keh-Ping; Wang, Ping; Wang, Ya-Ting

2007-04-02

The chemical resistance of eight organic solvents in high density polyethylene (HDPE) geomembrane has been investigated using the ASTM F739 permeation method and the immersion test at different temperatures. The diffusion of the experimental organic solvents in HDPE geomembrane was non-Fickian kinetic, and the solubility coefficients can be consistent with the solubility parameter theory. The diffusion coefficients and solubility coefficients determined by the ASTM F739 method were significantly correlated to the immersion tests (p<0.001). The steady state permeation rates also showed a good agreement between ASTM F739 and immersion experiments (r(2)=0.973, p<0.001). Using a one-dimensional diffusion equation based on Fick's second law, the diffusion and solubility coefficients obtained by immersion test resulted in over estimates of the ASTM F739 permeation results. The modeling results indicated that the diffusion and solubility coefficients should be obtained using ASTM F739 method which closely simulates the practical application of HDPE as barriers in the field.

Ideal gas solubilities and solubility selectivities in a binary mixture of room-temperature ionic liquids.

PubMed

Finotello, Alexia; Bara, Jason E; Narayan, Suguna; Camper, Dean; Noble, Richard D

2008-02-28

This study focuses on the solubility behaviors of CO2, CH4, and N2 gases in binary mixtures of imidazolium-based room-temperature ionic liquids (RTILs) using 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C2mim][Tf2N]) and 1-ethyl-3-methylimidazolium tetrafluoroborate ([C2mim][BF4]) at 40 degrees C and low pressures (approximately 1 atm). The mixtures tested were 0, 25, 50, 75, 90, 95, and 100 mol % [C2mim][BF4] in [C2mim][Tf2N]. Results show that regular solution theory (RST) can be used to describe the gas solubility and selectivity behaviors in RTIL mixtures using an average mixture solubility parameter or an average measured mixture molar volume. Interestingly, the solubility selectivity, defined as the ratio of gas mole fractions in the RTIL mixture, of CO2 with N2 or CH4 in pure [C2mim][BF4] can be enhanced by adding 5 mol % [C2mim][Tf2N].

The Legal Implication of Cultural Bias in the Intelligence Testing of Disadvantaged School Children

ERIC Educational Resources Information Center

Georgetown Law Journal, 1973

1973-01-01

The court cases and legal codes cited in this article include: Brown v. Board of Education, 1954; Hobson v. Hansen, 1967; Diana v. State Board of Education (Calif.), 1970; and, California Education Code, 1972. (SF)

From Self-Organized to Extended Criticality

DTIC Science & Technology

2012-04-26

Texas, Denton, TX, USA 2 Centro EXTREME, Scuola Superiore Sant’Anna, Pisa, Italy 3 Istituto di Fisiologia Clinica-CNR, Pisa, Italy 4 Department of Physics...Netherlands Klaus Linkenkaer-Hansen, Center for Neurogenomics and Cognitive Research, Netherlands *Correspondence: Paolo Allegrini , Istituto di Fisiologia

Hypersonic Boost Glider

NASA Image and Video Library

1957-04-15

Hypersonic Boost Glider in 11 Inch Hypersonic Tunnel L57-1681 In 1957 Langley tested its HYWARDS design in the 11 Inch Hypersonic Tunnel. Photograph published in Engineer in Charge: A History of the Langley Aeronautical Laboratory, 1917-1958 by James R. Hansen. Page 369.

Thermodynamic Solubility Profile of Carbamazepine-Cinnamic Acid Cocrystal at Different pH.

PubMed

Keramatnia, Fatemeh; Shayanfar, Ali; Jouyban, Abolghasem

2015-08-01

Pharmaceutical cocrystal formation is a direct way to dramatically influence physicochemical properties of drug substances, especially their solubility and dissolution rate. Because of their instability in the solution, thermodynamic solubility of cocrystals could not be determined in the common way like other compounds; therefore, the thermodynamic solubility is calculated through concentration of their components in the eutectic point. The objective of this study is to investigate the effect of an ionizable coformer in cocrystal with a nonionizable drug at different pH. Carbamazepine (CBZ), a nonionizable drug with cinnamic acid (CIN), which is an acidic coformer, was selected to prepare CBZ-CIN cocrystal and its thermodynamic solubility was studied in pH range 2-7. Instead of HPLC that is a costly and time-consuming method, a chemometric-based approach, net analyte signal standard addition method, was selected for simultaneous determination of CBZ and CIN in solution. The result showed that, as pH increases, CIN ionization leads to change in CBZ-CIN cocrystal solubility and stability in solution. In addition, the results of this study indicated that there is no significant difference between intrinsic solubility of CBZ and cocrystal despite the higher ideal solubility of cocrystal. This verifies that ideal solubility is not good parameter to predict cocrystal solubility. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

Method for determining processability of a hydrocarbon containing feedstock

DOEpatents

Schabron, John F.; Rovani, Jr., Joseph F.

2013-09-10

Disclosed herein is a method involving the steps of (a) precipitating an amount of asphaltenes from a liquid sample of a first hydrocarbon-containing feedstock having solvated asphaltenes therein with one or more first solvents in a column; (b) determining one or more solubility characteristics of the precipitated asphaltenes; (c) analyzing the one or more solubility characteristics of the precipitated asphaltenes; and (d) correlating a measurement of feedstock reactivity for the first hydrocarbon-containing feedstock sample with a mathematical parameter derived from the results of analyzing the one or more solubility characteristics of the precipitated asphaltenes.

Observation of oxide particles below the apparent oxygen solubility limit in tantalum

NASA Technical Reports Server (NTRS)

Stecura, S.

1973-01-01

The apparent solubility of oxygen in polycrystalline tantalum as determined by the X-ray diffraction lattice parameter technique is about 1.63 atomic percent at 820 C. However, oxide particles were identified in samples containing as low as 0.5 atomic percent of oxygen. These oxide particles were present at the grain boundaries and within the grains. The number of oxide particles increased with increasing oxygen concentration in tantalum. The presence of oxide particles suggests that the true solubility of oxygen in the polycrystalline tantalum metal is probably significantly lower than that reported in the literature.

Paraglider

NASA Image and Video Library

1961-06-30

Image L61-4369 is available as an electronic file from the photo lab. See URL. -- Photographed on 06/30/1961. -- Test of parawing in Full Scale Wind Tunnel. -- Published in James R. Hansen, Spaceflight Revolution: NASA Langley Research Center From Sputnik to Apollo, (Washington: NASA, 1995), pp. 380-387.

Organization Development. Symposium.

ERIC Educational Resources Information Center

2002

This document contains four papers on organization development and human resources. "Identification of Key Predictors of Rapid Change Adaptation in a Service Organization" (Constantine Kontoghiorghes, Carol Hansen) reports on the results of an exploratory study, which suggests that rapid change adaptation will be more likely to occur in…

Organization Values. Symposium 10. [AHRD Conference, 2001].

ERIC Educational Resources Information Center

2001

This document contains three papers on organizational values. "Understanding the Work Beliefs of Nonprofit Executives through Organizational Stories" (Ava S. Wilensky, Carol D. Hansen) reports on a study during which qualitative interviews featuring a story component established that nonprofit executives constitute a diffuse managerial…

Impact of process parameters on the breakage kinetics of poorly water-soluble drugs during wet stirred media milling: a microhydrodynamic view.

PubMed

Afolabi, Afolawemi; Akinlabi, Olakemi; Bilgili, Ecevit

2014-01-23

Wet stirred media milling has proven to be a robust process for producing nanoparticle suspensions of poorly water-soluble drugs. As the process is expensive and energy-intensive, it is important to study the breakage kinetics, which determines the cycle time and production rate for a desired fineness. Although the impact of process parameters on the properties of final product suspensions has been investigated, scant information is available regarding their impact on the breakage kinetics. Here, we elucidate the impact of stirrer speed, bead concentration, and drug loading on the breakage kinetics via a microhydrodynamic model for the bead-bead collisions. Suspensions of griseofulvin, a model poorly water-soluble drug, were prepared in the presence of two stabilizers: hydroxypropyl cellulose and sodium dodecyl sulfate. Laser diffraction, scanning electron microscopy, and rheometry were used to characterize them. Various microhydrodynamic parameters including a newly defined milling intensity factor was calculated. An increase in either the stirrer speed or the bead concentration led to an increase in the specific energy and the milling intensity factor, consequently faster breakage. On the other hand, an increase in the drug loading led to a decrease in these parameters and consequently slower breakage. While all microhydrodynamic parameters provided significant physical insight, only the milling intensity factor was capable of explaining the influence of all parameters directly through its strong correlation with the process time constant. Besides guiding process optimization, the analysis rationalizes the preparation of a single high drug-loaded batch (20% or higher) instead of multiple dilute batches. Copyright © 2013 Elsevier B.V. All rights reserved.

[Behavior of soluble L-selectin in HIV infected children].

PubMed

Gaddi, E; Balbaryski, J; Cantisano, C; Barboni, G; Candi, M; Quiroz, H; Giraudi, V

2001-01-01

L-selectin is an adhesion molecule that is responsible for the initial attachment of leukocytes to endothelium. After leukocyte activation L-selectin is endoproteolytically released from the cell surface. In order to analyze the relationship between soluble L-selectin (sL-selectin) and parameters of immune activation and disease progression, 51 HIV infected children and 15 healthy controls were studied. Serum L-selectin concentrations were significantly higher in HIV infected children than in the control group. Levels of sL-selectin were higher in HIV infected patients with severe immunologic suppression than in those with moderate or no evidence of suppression. A positive correlation between sL-selectin levels and LTCD8 counts, sL-selectin and soluble intercellular adhesion molecule-1 (sICAM-1) and immunogobulin A (IgA) levels was detected. On the contrary sL-selectin concentration did not correlate with plasmatic viral load. The correlation with parameters of immune activation may implicate involvement of sL-selectin in the immunopathogenesis of HIV infection.

Application of a polarity parameter model to the separation of fat-soluble vitamins by reversed-phase HPLC.

PubMed

Herrero-Martínez, José Manuel; Izquierdo, Pere; Sales, Joaquim; Rosés, Martí; Bosch, Elisabeth

2008-10-01

The retention behavior of a series of fat-soluble vitamins has been established on the basis of a polarity retention model: log k = (log k)(0) + p (P(m) (N) - P(s) (N)), with p being the polarity of the solute, P(m) (N) the mobile phase polarity, and (log k)(0) and P(m) (N) two parameters for the characterization of the stationary phase. To estimate the p-values of solutes, two approaches have been considered. The first one is based on the application of a QSPR model, derived from the molecular structure of solutes and their log P(o/w), while in the second one, the p-values are obtained from several experimental measurements. The quality of prediction of both approaches has also been evaluated, with the second one giving more accurate results for the most lipophilic vitamins. This model allows establishing the best conditions to separate and determine simultaneously some fat-soluble vitamins in dairy foods.

Soluble Milk Protein Supplementation with Moderate Physical Activity Improves Locomotion Function in Aging Rats.

PubMed

Lafoux, Aude; Baudry, Charlotte; Bonhomme, Cécile; Le Ruyet, Pascale; Huchet, Corinne

2016-01-01

Aging is associated with a loss of muscle mass and functional capacity. Present study was designed to compare the impact of specific dairy proteins on muscular function with or without a low-intensity physical activity program on a treadmill in an aged rat model. We investigated the effects of nutritional supplementation, five days a week over a 2-month period with a slow digestible protein, casein or fast digestible proteins, whey or soluble milk protein, on strength and locomotor parameters in sedentary or active aged Wistar RjHan rats (17-19 months of age). An extensive gait analysis was performed before and after protein supplementation. After two months of protein administration and activity program, muscle force was evaluated using a grip test, spontaneous activity using an open-field and muscular mass by specific muscle sampling. When aged rats were supplemented with proteins without exercise, only minor effects of different diets on muscle mass and locomotion were observed: higher muscle mass in the casein group and improvement of stride frequencies with soluble milk protein. By contrast, supplementation with soluble milk protein just after physical activity was more effective at improving overall skeletal muscle function in old rats compared to casein. For active old rats supplemented with soluble milk protein, an increase in locomotor activity in the open field and an enhancement of static and dynamic gait parameters compared to active groups supplemented with casein or whey were observed without any differences in muscle mass and forelimb strength. These results suggest that consumption of soluble milk protein as a bolus immediately after a low intensity physical activity may be a suitable nutritional intervention to prevent decline in locomotion in aged rats and strengthen the interest to analyze the longitudinal aspect of locomotion in aged rodents.

Soluble Milk Protein Supplementation with Moderate Physical Activity Improves Locomotion Function in Aging Rats

PubMed Central

Lafoux, Aude; Baudry, Charlotte; Bonhomme, Cécile; Le Ruyet, Pascale; Huchet, Corinne

2016-01-01

Aging is associated with a loss of muscle mass and functional capacity. Present study was designed to compare the impact of specific dairy proteins on muscular function with or without a low-intensity physical activity program on a treadmill in an aged rat model. We investigated the effects of nutritional supplementation, five days a week over a 2-month period with a slow digestible protein, casein or fast digestible proteins, whey or soluble milk protein, on strength and locomotor parameters in sedentary or active aged Wistar RjHan rats (17–19 months of age). An extensive gait analysis was performed before and after protein supplementation. After two months of protein administration and activity program, muscle force was evaluated using a grip test, spontaneous activity using an open-field and muscular mass by specific muscle sampling. When aged rats were supplemented with proteins without exercise, only minor effects of different diets on muscle mass and locomotion were observed: higher muscle mass in the casein group and improvement of stride frequencies with soluble milk protein. By contrast, supplementation with soluble milk protein just after physical activity was more effective at improving overall skeletal muscle function in old rats compared to casein. For active old rats supplemented with soluble milk protein, an increase in locomotor activity in the open field and an enhancement of static and dynamic gait parameters compared to active groups supplemented with casein or whey were observed without any differences in muscle mass and forelimb strength. These results suggest that consumption of soluble milk protein as a bolus immediately after a low intensity physical activity may be a suitable nutritional intervention to prevent decline in locomotion in aged rats and strengthen the interest to analyze the longitudinal aspect of locomotion in aged rodents. PMID:27973615

PARAMETERS OF TEXTURE CHANGE IN PROCESSED FISH: CROSS-LINKAGE OF PROTEINS.

PubMed

Mao, Wei-Wen; Sterling, Clarence

1970-11-01

Soluble myosin and insoluble protein (i. e., soluble only in 5 % sodium dodecyl sulfate) were obtained from fresh and processed Sacramento blackfish and analyzed for the existence of possible cross-links. Free sulfhydryl groups decreased somewhat in freezing and more in frozen storage. None were present after dehydration or cooking nor in any insoluble fractions, so that presumably these were oxidized in the formation of cross-links. Ester bonds were much more numerous in insoluble protein than in soluble myosin, but their relative content was not clearly related to processing. Aldehyde groups decreased in myosin after cooking and dehydration, and were absent from insoluble protein. The presumptive Schiff base content was somewhat greater in soluble protein than in myosin and appeared to increase upon freezing and dehydration.

Microbial metabolism and dynamic changes in the electrical conductivity of soil solutions - A method for detecting extraterrestrial life

NASA Technical Reports Server (NTRS)

Silverman, M. P.; Munoz, E. F.

1974-01-01

Experiments are reported which show that measuring metabolic activity in soil solutions by means of dynamic changes in electrical conductivity, water-soluble Ca, or water-soluble Mg is a feasible life detection method. The addition of 0.5% glucose solutions to 12 different air-dried soils always resulted in increases in all three of these parameters. The kinetics and magnitude of these changes for at least two and usually all three of the parameters over a 14-day period were clearly distinguishable from the changes in heat-sterilized controls or unsterilized controls without added glucose. In general, maximal values were achieved more rapidly under aerobic than under anaerobic incubation.

Lipid Class, Carotenoid, and Toxin Dynamics of Karenia Brevis (Dinophyceae) During Diel Vertical Migration

EPA Science Inventory

Karenia brevis’ (Hansen and Moestrup) internal lipid, carotenoid, and toxin concentrations are influenced by its ability to use ambient light and nutrients for growth and reproduction. This project investigated changes of K. brevis toxicity, lipid class and carotenoid concentrat...

Digital dissemination platform of transportation engineering education materials founded in adoption research : [summary].

DOT National Transportation Integrated Search

2014-04-01

National interest abounds in improving engineering education in the US. This interest stems from low performance on concept inventories (P.S. Steif, Dollar, & Dantzler, : 2005; Paul S Steif & Hansen, 2006) concerns over the role of the US as a nation...

Celebrate Your Freedom! May 1, Law Day 1997.

ERIC Educational Resources Information Center

Michaud, Mike; And Others

1997-01-01

Presents seven brief articles on legal issues concerning young people. Addresses such topics as curfews, teen smoking, dress codes, and child labor. Some articles are student-written while others profile student activity. Student authors include Mike Michaud, Danny Rosen, Carrie Kendrick, and William Hansen. (MJP)

Phytophthora siskiyouensis

Treesearch

E. M. Hansen; P. Reeser; S. Rooney-Latham

2011-01-01

Phytophthora siskiyouensis Reeser & E.M. Hansen (2007) was discovered first in streams and soil in Curry County, Oregon in areas dominated by native forest, and most isolates continue to come from these sources. Only later, and still infrequently, were isolates of the new species recovered from diseased forest plants. Recent...

Army Materiel Requirements Documents: Qualitative Analysis of Efficiency and Effectiveness

DTIC Science & Technology

2013-06-01

MASTER OF BUSINESS ADMINISTRATION from the NAVAL POSTGRADUATE SCHOOL June 2013 Authors: _____________________________________ Anh H...Graduate School of Business and Public Policy _____________________________________ Jason K. Hansen Defense Resources Management Institute...William R. Gates, Dean Graduate School of Business and Public Policy iv THIS PAGE INTENTIONALLY

Rejoinder to Lemberger

ERIC Educational Resources Information Center

Hansen, James T.

2012-01-01

Lemberger (2012) argues that the author (Hansen, 2012) has no basis for recommending differential weightings or priorities to humanism and science, because those ideologies are only meaningful as they are subjectively interpreted within the counseling encounter. The author responds that their positions are completely compatible, but his focus was…

A Review of Physical Activity Levels during Elementary School Physical Education

ERIC Educational Resources Information Center

Fairclough, Stuart J.; Stratton, Gareth

2006-01-01

Regular physical activity participation throughout childhood provides benefits to physical (Malina, Bouchard, & Bar-Or, 2004), physiological (Andersen, Wedderkopp, Hansen, Cooper, & Froberg, 2003), and psychological health (Mutrie & Parfitt, 1998). In recognition of these benefits, guidelines have been published in the United States…

Transforming Teacher Education: Lessons in Professional Development.

ERIC Educational Resources Information Center

Sockett, Hugh T., Ed.; DeMulder, Elizabeth K., Ed.; LePage, Pamela C., Ed.; Wood, Diane R., Ed.

This book investigates many aspects of educational reform, pivoting around an innovative master's degree program for teachers. After "Foreword" (David T. Hansen), there are 14 papers: (1) "Transforming Teacher Education" (Hugh T. Sockett); (2) "From Educational Rhetoric to Program Reality" (Hugh T. Sockett and Pamela…

Multiple Imputation for Multivariate Missing-Data Problems: A Data Analyst's Perspective.

ERIC Educational Resources Information Center

Schafer, Joseph L.; Olsen, Maren K.

1998-01-01

The key ideas of multiple imputation for multivariate missing data problems are reviewed. Software programs available for this analysis are described, and their use is illustrated with data from the Adolescent Alcohol Prevention Trial (W. Hansen and J. Graham, 1991). (SLD)

Tri-Level Optimization Algorithms for Solving Defender-Attacker-Defender Network Models

DTIC Science & Technology

2016-06-01

ed.). New York: Springer. Brimberg, J., Hansen, P., Lin, K., Mladenović, N., & Breton, M. (2003). An Oil Pipeline Design Problem. Operations...H. (2012). Critical infrastructure protection: The vulnerability conundrum. Telematics and informatics , 29(1), 56–65. Retrieved from http

Comparative study of stability of soluble and cell wall invertase from Saccharomyces cerevisiae.

PubMed

Margetić, Aleksandra; Vujčić, Zoran

2017-03-16

Yeast Saccharomyces cerevisiae is the most significant source of enzyme invertase. It is mainly used in the food industry as a soluble or immobilized enzyme. The greatest amount of invertase is located in the periplasmic space in yeast. In this work, it was isolated into two forms of enzyme from yeast S. cerevisiae cell, soluble and cell wall invertase (CWI). Both forms of enzyme showed same temperature optimum (60°C), similar pH optimum, and kinetic parameters. The significant difference between these biocatalysts was observed in their thermal stability, stability in urea and methanol solution. At 60°C, CWI had 1.7 times longer half-life than soluble enzyme, while at 70°C CWI showed 8.7 times longer half-life than soluble enzyme. After 2-hr of incubation in 8 M urea solution, soluble invertase and CWI retained 10 and 60% of its initial activity, respectively. During 22 hr of incubation of both enzymes in 30 and 40% methanol, soluble invertase was completely inactivated, while CWI changed its activity within the experimental error. Therefore, soluble invertase and CWI have not shown any substantial difference, but CWI showed better thermal stability and stability in some of the typical protein-denaturing agents.

Solubility of pharmaceuticals: A comparison between SciPharma, a PC-SAFT-based approach, and NRTL-SAC

NASA Astrophysics Data System (ADS)

Bouillot, Baptiste; Spyriouni, Theodora; Teychené, Sébastien; Biscans, Béatrice

2017-04-01

The solubility of seven pharmaceutical compounds (paracetamol, benzoic acid, 4-aminobenzoic acid, salicylic acid, ibuprofen, naproxen and temazepam) in pure and mixed solvents as a function of temperature is calculated with SciPharma, a semi-empirical approach based on PC-SAFT, and the NRTL-SAC model. To conduct a fair comparison between the approaches, the parameters of the compounds were regressed against the same solubility data, chosen to account for hydrophilic, polar and hydrophobic interactions. Only these solubility data were used by both models for predicting solubility in other pure and mixed solvents for which experimental data were available for comparison. A total of 386 pure solvent data points were used for the comparison comprising one or more temperatures per solvent. SciPharma is found to be more accurate than NRTL-SAC on the pure solvent data used especially in the description of the temperature dependence. This is due to the appropriate parameterization of the pharmaceuticals and the temperature-dependent description of the activity coefficient in PC-SAFT. The solubility in mixed solvents is predicted satisfactorily with SciPharma. NRTL-SAC tends to overestimate the solubility in aqueous solutions of alcohols or shows invariable solubility with composition in other cases.

The Exile of Hansen's Disease Patients to Moloka'i: A Diffusion of Innovations Perspective.

PubMed

Pitman Harris, Adrea; Matusitz, Jonathan

2016-07-01

This article analyzes the exile of patients with Hansen's disease (leprosy) to Moloka'i (Hawaii) by applying the diffusion of innovations (DoI) theory. Developed by Rogers, DoI posits that an innovation (i.e., idea, movement, or trend) is initiated within a culture. Then, it is diffused via particular channels across diverse cultures. Instead of evolving independently, innovations diffuse from one culture to another through various forms of contact and communication. In the context of this analysis, the objective is to examine how the diffusion of certain ideas, namely, abolishing the stigma associated with leprosy, could have improved the lives of Hawaiians. An important premise of this article is that the Hawaiian government barely applied the tenets of DoI, which is the reason why many people lost their lives. So, this article seeks to explore what could have been done to improve their situation and what pitfalls should be avoided in the future.

U.S. Coast Guard Cutter Healy in the Beaufort Sea

NASA Image and Video Library

2017-12-08

Scientists on board the U.S. Coast Guard Cutter Healy in the Beaufort Sea, northeast of Barrow, Alaska, finished collecting the mission¹s sea ice data and cruised south on July 20, 2011, through thin ice and ultimately into the open ocean. The ICESCAPE mission, or "Impacts of Climate on Ecosystems and Chemistry of the Arctic Pacific Environment," is a NASA shipborne investigation to study how changing conditions in the Arctic affect the ocean's chemistry and ecosystems. The bulk of the research took place in the Beaufort and Chukchi seas in summer 2010 and 2011. Credit: NASA/Kathryn Hansen Credit: NASA/Kathryn Hansen NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Meeting the privacy requirements for the development of a multi-centre patient registry in Canada: the Rick Hansen Spinal Cord Injury Registry.

PubMed

Noonan, Vanessa K; Thorogood, Nancy P; Joshi, Phalgun B; Fehlings, Michael G; Craven, B Catharine; Linassi, Gary; Fourney, Daryl R; Kwon, Brian K; Bailey, Christopher S; Tsai, Eve C; Drew, Brian M; Ahn, Henry; Tsui, Deborah; Dvorak, Marcel F

2013-05-01

Privacy legislation addresses concerns regarding the privacy of personal information; however, its interpretation by research ethics boards has resulted in significant challenges to the collection, management, use and disclosure of personal health information for multi-centre research studies. This paper describes the strategy used to develop the national Rick Hansen Spinal Cord Injury Registry (RHSCIR) in accordance with privacy statutes and benchmarked against best practices. An analysis of the regional and national privacy legislation was conducted to determine the requirements for each of the 31 local RHSCIR sites and the national RHSCIR office. A national privacy and security framework was created for RHSCIR that includes a governance structure, standard operating procedures, training processes, physical and technical security and privacy impact assessments. The framework meets a high-water mark in ensuring privacy and security of personal health information nationally and may assist in the development of other national or international research initiatives. Copyright © 2013 Longwoods Publishing.

Reaction of Prunus Rootstocks to Meloidogyne incognita and M. arenaria in Spain

PubMed Central

Marull, J.; Pinochet, J.; Verdejo-Lucas, S.; Soler, A.

1991-01-01

Prunus rootstocks were evaluated for their reaction to Meloidogyne incognita and M. arenaria. Most rootstocks were peach-almond hybrids of Spanish origin. In one experiment three selections of Garfi x Nemared (G x N) and Hansen-5 were highly resistant to M. incognita, but four other rootstocks were susceptible showing high galling indices and population increases. In two experiments with M. arenaria, the hybrid selections G x N nos. 1 and 9 were immune, GF-305 and Hansen-5 were resistant, but nine other rootstocks expressed various degrees of susceptibility. All Spanish rootstocks were susceptible to both Meloidogyne species except for the three G x N selections. The root-knot nematode resistant peach Nemared used as a male parent with Garfi was found to transmit a high degree of resistance to M. incognita and immunity to M. arenaria. Progenies of P. davidiana (Ga x D no. 3), a known source of resistance to root-knot nematodes, were susceptible. PMID:19283164

Meeting the Privacy Requirements for the Development of a Multi-Centre Patient Registry in Canada: The Rick Hansen Spinal Cord Injury Registry

PubMed Central

Noonan, Vanessa K.; Thorogood, Nancy P.; Joshi, Phalgun B.; Fehlings, Michael G.; Craven, B. Catharine; Linassi, Gary; Fourney, Daryl R.; Kwon, Brian K.; Bailey, Christopher S.; Tsai, Eve C.; Drew, Brian M.; Ahn, Henry; Tsui, Deborah; Dvorak, Marcel F.

2013-01-01

Privacy legislation addresses concerns regarding the privacy of personal information; however, its interpretation by research ethics boards has resulted in significant challenges to the collection, management, use and disclosure of personal health information for multi-centre research studies. This paper describes the strategy used to develop the national Rick Hansen Spinal Cord Injury Registry (RHSCIR) in accordance with privacy statutes and benchmarked against best practices. An analysis of the regional and national privacy legislation was conducted to determine the requirements for each of the 31 local RHSCIR sites and the national RHSCIR office. A national privacy and security framework was created for RHSCIR that includes a governance structure, standard operating procedures, training processes, physical and technical security and privacy impact assessments. The framework meets a high-water mark in ensuring privacy and security of personal health information nationally and may assist in the development of other national or international research initiatives. PMID:23968640

Multipole moments of bumpy black holes

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

Vigeland, Sarah J.

General relativity predicts the existence of black holes, compact objects whose spacetimes depend only on their mass, spin, and charge in vacuum (the 'no-hair' theorem). As various observations probe deeper into the strong fields of black hole candidates, it is becoming possible to test this prediction. Previous work suggested that such tests can be performed by measuring whether the multipolar structure of black hole candidates has the form that general relativity demands, and introduced a family of 'bumpy black hole' spacetimes to be used for making these measurements. These spacetimes have generalized multipoles, where the deviation from the Kerr metricmore » depends on the spacetime's 'bumpiness'. In this paper, we show how to compute the Geroch-Hansen moments of a bumpy black hole, demonstrating that there is a clean mapping between the deviations used in the bumpy black hole formalism and the Geroch-Hansen moments. We also extend our previous results to define bumpy black holes whose current moments, analogous to magnetic moments of electrodynamics, deviate from the canonical Kerr value.« less

Little Joe Model Mercury Project

NASA Image and Video Library

1959-06-26

Publicity photograph of a technician measuring a wind tunnel model of the Little Joe test vehicle. Joseph Shortal noted that (vol. 3, p. 29): The largest project at Wallops in support of Mercury was the Little Joe project, designed to qualify the abort-escape system under flight conditions. James Hansen (p. 47) writes: STG engineers Max Faget and Paul Purser, then of Langley's PARD, had conceived Little Joe as a space capsule test vehicle even before the establishment of NASA and the formation of the STG. Girlruth understood the importance of the Little Joe tests: We had to be sure there were no serious performance and operational problems that we had simply not thought of in such a new and radical type of flight vehicle. -- Published in James R. Hansen, Spaceflight Revolution: NASA Langley Research Center From Sputnik to Apollo, (Washington: NASA, 1995), p. 47 Joseph A. Shortal, History of Wallops Station: Origins and Activities Through 1949, (Wallops Island, VA: National Aeronautics and Space Administration, Wallops Station, nd), Comment Edition.

Low-molecular-weight gelators: elucidating the principles of gelation based on gelator solubility and a cooperative self-assembly model.

PubMed

Hirst, Andrew R; Coates, Ian A; Boucheteau, Thomas R; Miravet, Juan F; Escuder, Beatriu; Castelletto, Valeria; Hamley, Ian W; Smith, David K

2008-07-16

This paper highlights the key role played by solubility in influencing gelation and demonstrates that many facets of the gelation process depend on this vital parameter. In particular, we relate thermal stability ( T gel) and minimum gelation concentration (MGC) values of small-molecule gelation in terms of the solubility and cooperative self-assembly of gelator building blocks. By employing a van't Hoff analysis of solubility data, determined from simple NMR measurements, we are able to generate T calc values that reflect the calculated temperature for complete solubilization of the networked gelator. The concentration dependence of T calc allows the previously difficult to rationalize "plateau-region" thermal stability values to be elucidated in terms of gelator molecular design. This is demonstrated for a family of four gelators with lysine units attached to each end of an aliphatic diamine, with different peripheral groups (Z or Boc) in different locations on the periphery of the molecule. By tuning the peripheral protecting groups of the gelators, the solubility of the system is modified, which in turn controls the saturation point of the system and hence controls the concentration at which network formation takes place. We report that the critical concentration ( C crit) of gelator incorporated into the solid-phase sample-spanning network within the gel is invariant of gelator structural design. However, because some systems have higher solubilities, they are less effective gelators and require the application of higher total concentrations to achieve gelation, hence shedding light on the role of the MGC parameter in gelation. Furthermore, gelator structural design also modulates the level of cooperative self-assembly through solubility effects, as determined by applying a cooperative binding model to NMR data. Finally, the effect of gelator chemical design on the spatial organization of the networked gelator was probed by small-angle neutron and X-ray scattering (SANS/SAXS) on the native gel, and a tentative self-assembly model was proposed.

Utilizing the social media data to validate 'climate change' indices

NASA Astrophysics Data System (ADS)

Molodtsova, T.; Kirilenko, A.; Stepchenkova, S.

2013-12-01

Reporting the observed and modeled changes in climate to public requires the measures understandable by the general audience. E.g., the NASA GISS Common Sense Climate Index (Hansen et al., 1998) reports the change in climate based on six practically observable parameters such as the air temperature exceeding the norm by one standard deviation. The utility of the constructed indices for reporting climate change depends, however, on an assumption that the selected parameters are felt and connected with the changing climate by a non-expert, which needs to be validated. Dynamic discussion of climate change issues in social media may provide data for this validation. We connected the intensity of public discussion of climate change in social networks with regional weather variations for the territory of the USA. We collected the entire 2012 population of Twitter microblogging activity on climate change topic, accumulating over 1.8 million separate records (tweets) globally. We identified the geographic location of the tweets and associated the daily and weekly intensity of twitting with the following parameters of weather for these locations: temperature anomalies, 'hot' temperature anomalies, 'cold' temperature anomalies, heavy rain/snow events. To account for non-weather related events we included the articles on climate change from the 'prestige press', a collection of major newspapers. We found that the regional changes in parameters of weather significantly affect the number of tweets published on climate change. This effect, however, is short-lived and varies throughout the country. We found that in different locations different weather parameters had the most significant effect on climate change microblogging activity. Overall 'hot' temperature anomalies had significant influence on climate change twitting intensity.

Computational study of the melting-freezing transition in the quantum hard-sphere system for intermediate densities. II. Structural features.

PubMed

Sesé, Luis M; Bailey, Lorna E

2007-04-28

The structural features of the quantum hard-sphere system in the region of the fluid-face-centered-cubic-solid transition, for reduced number densities 0.45

Parameters influencing the course of passive drug loading into lipid nanoemulsions.

PubMed

Göke, Katrin; Bunjes, Heike

2018-05-01

Passive drug loading can be used to effectively identify suitable colloidal lipid carrier systems for poorly water-soluble drugs. This method comprises incubation of preformed carrier systems with drug powder and subsequent determination of the resulting drug load of the carrier particles. Until now, the passive loading mechanism is unknown, which complicates reliable routine use. In this work, the influence of drug characteristics on the course of passive loading was investigated systematically varying drug surface area and drug solubility. Fenofibrate and flufenamic acid were used as model drugs; the carrier system was a trimyristin nanodispersion. Loading progress was analyzed by UV spectroscopy or by a novel method based on differential scanning calorimetry. While increasing drug solubility by micelle incorporation did not speed up passive loading, a large drug surface area and high water solubility were key parameters for fast loading. Since both factors are crucial in drug dissolution as described by the Noyes-Whitney equation, these findings point to a dissolution-diffusion-based passive loading mechanism. Accordingly, passive loading also occurred when drug and carrier particles were separated by a dialysis membrane. Knowledge of the loading mechanism allows optimizing the conditions for future passive loading studies and assessing the limitations of the method. Copyright © 2017 Elsevier B.V. All rights reserved.

Controlled poorly soluble drug release from solid self-microemulsifying formulations with high viscosity hydroxypropylmethylcellulose.

PubMed

Yi, Tao; Wan, Jiangling; Xu, Huibi; Yang, Xiangliang

2008-08-07

The objective of this work was the development of a controlled release system based on self-microemulsifying mixture aimed for oral delivery of poorly water-soluble drugs. HPMC-based particle formulations were prepared by spray drying containing a model drug (nimodipine) of low water solubility and hydroxypropylmethylcellulose (HPMC) of high viscosity. One type of formulations contained nimodipine mixed with HPMC and the other type of formulations contained HPMC and nimodipine dissolved in a self-microemulsifying system (SMES) consisting of ethyl oleate, Cremophor RH 40 and Labrasol. Based on investigation by transmission electron microscopy (TEM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and X-ray powder diffraction, differences were found in the particle structure between both types of formulations. In vitro release was performed and characterized by the power law. Nimodipine release from both types of formulations showed a controlled release profile and the two power law parameters, n and K, correlated to the viscosity of HPMC. The parameters were also influenced by the presence of SMES. For the controlled release solid SMES, oil droplets containing dissolved nimodipine diffused out of HPMC matrices following exposure to aqueous media. Thus, it is possible to control the in vitro release of poorly soluble drugs from solid oral dosage forms containing SMES.

An investigation of the thermodynamic miscibility between VeTPGS and polymers.

PubMed

Li, Jinjiang; Chiappetta, Doris

2008-02-28

Within the past decade, more than half of the drug candidates generated are poorly water soluble and therefore overcoming the low aqueous solubility of drug candidates becomes critical for product development. Vitamin E TPGS (VeTPGS), a non-ionic surfactant, has been used in both liquid and solid dosage forms to solubilize compounds and improve their bioavailability. To prepare solid dosage forms using VeTPGS, VeTPGS is often mixed with other excipients, mostly polymers. However, there is still a lack of understanding of miscibility between VeTPGS and polymers from a thermodynamic point of view. In this paper, the miscibility of VeTPGS with polymers has been studied in the light of the Flory-Huggins (F-H) theory with an objective to understand the effect of dispersion forces (solubility parameter) and nondispersive interactions on the miscibility between VeTPGS and polymers. A series of polymers with similar solubility parameters and structure similarity were selected. Binary blends of polymers and VeTPGS were prepared using a vapor evaporation technique followed by XRPD, DSC, and SEM characterization. Results suggest that the miscibility between VeTPGS and PMMA is very likely due to a specific interaction between the hydrophobic portion of VeTPGS (Vitamin E) and PMMA.

Role of Self-Association and Supersaturation in Oral Absorption of a Poorly Soluble Weakly Basic Drug.

PubMed

Narang, Ajit S; Badawy, Sherif; Ye, Qingmei; Patel, Dhaval; Vincent, Maria; Raghavan, Krishnaswamy; Huang, Yande; Yamniuk, Aaron; Vig, Balvinder; Crison, John; Derbin, George; Xu, Yan; Ramirez, Antonio; Galella, Michael; Rinaldi, Frank A

2015-08-01

Precipitation of weakly basic drugs in intestinal fluids can affect oral drug absorption. In this study, the implications of self-association of brivanib alaninate in acidic aqueous solution, leading to supersaturation at basic pH condition, on its solubility and oral absorption were investigated. Self-association of brivanib alaninate was investigated by proton NMR spectroscopy, surface tension measurement, dynamic light scattering, isothermal titration calorimetry, and molecular modeling. Drug solubility was determined in various pH media, and its tendency to supersaturate upon pH shift was investigated in buffered and biorelevant aqueous solutions. Pharmacokinetic modeling of human oral drug absorption was utilized for parameter sensitivity analyses of input variables. Brivanib alaninate exhibited continuous, and pH- and concentration-dependent self-association. This phenomenon resulted in positive deviation of drug solubility at acidic pH and the formation of a stable supersaturated drug solution in pH-shift assays. Consistent with the supersaturation phenomenon observed in vitro, oral absorption simulations necessitated invoking long precipitation time in the intestine to successfully predict in vivo data. Self-association of a weakly basic drug in acidic aqueous solution can increase its oral absorption by supersaturation and precipitation resistance at the intestinal pH. This consideration is important to the selection of parameters for oral absorption simulation.

Preparation of free, soluble conjugate, and insoluble-bound phenolic compounds from peels of rambutan (Nephelium lappaceum) and evaluation of antioxidant activities in vitro.

PubMed

Sun, Liping; Zhang, Huilin; Zhuang, Yongliang

2012-02-01

The soluble phenolic compounds of rambutan peels (RP) were extracted by microwave-assisted extraction (MAE) and the operating parameters were optimized. The optimal conditions obtained were ethanol concentration of 80.85%, extraction time of 58.39 s, and the ratio of liquid to solid of 24.51:1. The soluble phenolic content by MAE was 213.76 mg GAE/g DW. The free, soluble conjugate, and insoluble-boaund phenolic compounds were prepared by alkaline hydrolysis, and the contents of 3 fractions were 185.12, 27.98 and 9.37 mg GAE/g DW, respectively. The contents of syringic acid and p-coumaric acid were high in the free fraction, showing 16.86 and 19.44 mg/g DW, and the soluble conjugate and insoluble-bound phenolics were mainly composed of gallic acid and caffeic acid. Furthermore, the antioxidant activities of 3 fractions were evaluated in 5 model systems. Results indicated that the free fraction had high antioxidant activities, compared with the soluble conjugate and insoluble-bound fractions. © 2012 Institute of Food Technologists®

Partition Coefficients of Organics between Water and Carbon Dioxide Revisited: Correlation with Solute Molecular Descriptors and Solvent Cohesive Properties.

PubMed

Roth, Michal

2016-12-06

High-pressure phase behavior of systems containing water, carbon dioxide and organics has been important in several environment- and energy-related fields including carbon capture and storage, CO 2 sequestration and CO 2 -assisted enhanced oil recovery. Here, partition coefficients (K-factors) of organic solutes between water and supercritical carbon dioxide have been correlated with extended linear solvation energy relationships (LSERs). In addition to the Abraham molecular descriptors of the solutes, the explanatory variables also include the logarithm of solute vapor pressure, the solubility parameters of carbon dioxide and water, and the internal pressure of water. This is the first attempt to include also the properties of water as explanatory variables in LSER correlations of K-factor data in CO 2 -water-organic systems. Increasing values of the solute hydrogen bond acidity, the solute hydrogen bond basicity, the solute dipolarity/polarizability, the internal pressure of water and the solubility parameter of water all tend to reduce the K-factor, that is, to favor the solute partitioning to the water-rich phase. On the contrary, increasing values of the solute characteristic volume, the solute vapor pressure and the solubility parameter of CO 2 tend to raise the K-factor, that is, to favor the solute partitioning to the CO 2 -rich phase.

A return to the genetic heritage of durum wheat to cope with drought heightened by climate change.

PubMed

Slama, Amor; Mallek-Maalej, Elhem; Ben Mohamed, Hatem; Rhim, Thouraya; Radhouane, Leila

2018-01-01

The objective of this work was to perform a comparative analysis of the physiological, biochemical and agronomical parameters of recent and heritage durum wheat cultivars (Triticum durum Desf.) under water-deficit conditions. Five cultivars were grown under irrigated (control) and rainfall (stressed) conditions. Different agro-physiological and biochemical parameters were studied: electrolyte leakage, relative water content, chlorophyll fluorescence, proline, soluble sugars, specific peroxidase activity, yield and drought stress indices. It was revealed that a water deficit increased proline content, electrolyte leakage, soluble sugars and specific peroxidase activity and decreased relative water content, fluorescence and grain yield. According to these parameters and drought stress indices, our investigation indicated that old cultivars are the best-adapted to local conditions and showed characteristics of drought tolerance, while recent cultivars showed more drought susceptibility. Therefore, local cultivars of each country should be kept by farmers and plant breeders to preserve their genetic heritage.

Mass Transport through Nanostructured Membranes: Towards a Predictive Tool

PubMed Central

Darvishmanesh, Siavash; Van der Bruggen, Bart

2016-01-01

This study proposes a new mechanism to understand the transport of solvents through nanostructured membranes from a fundamental point of view. The findings are used to develop readily applicable mathematical models to predict solvent fluxes and solute rejections through solvent resistant membranes used for nanofiltration. The new model was developed based on a pore-flow type of transport. New parameters found to be of fundamental importance were introduced to the equation, i.e., the affinity of the solute and the solvent for the membrane expressed as the hydrogen-bonding contribution of the solubility parameter for the solute, solvent and membrane. A graphical map was constructed to predict the solute rejection based on the hydrogen-bonding contribution of the solubility parameter. The model was evaluated with performance data from the literature. Both the solvent flux and the solute rejection calculated with the new approach were similar to values reported in the literature. PMID:27918434

Determination of the design space of the HPLC analysis of water-soluble vitamins.

PubMed

Wagdy, Hebatallah A; Hanafi, Rasha S; El-Nashar, Rasha M; Aboul-Enein, Hassan Y

2013-06-01

Analysis of water-soluble vitamins has been tremendously approached through the last decades. A multitude of HPLC methods have been reported with a variety of advantages/shortcomings, yet, the design space of HPLC analysis of these vitamins was not defined in any of these reports. As per the food and drug administration (FDA), implementing the quality by design approach for the analysis of commercially available mixtures is hypothesized to enhance the pharmaceutical industry via facilitating the process of analytical method development and approval. This work illustrates a multifactorial optimization of three measured plus seven calculated influential HPLC parameters on the analysis of a mixture containing seven common water-soluble vitamins (B1, B2, B6, B12, C, PABA, and PP). These three measured parameters are gradient time, temperature, and ternary eluent composition (B1/B2) and the seven calculated parameters are flow rate, column length, column internal diameter, dwell volume, extracolumn volume, %B (start), and %B (end). The design is based on 12 experiments in which, examining of the multifactorial effects of these 3 + 7 parameters on the critical resolution and selectivity, was carried out by systematical variation of all these parameters simultaneously. The 12 basic runs were based on two different gradient time each at two different temperatures, repeated at three different ternary eluent compositions (methanol or acetonitrile or a mixture of both). Multidimensional robust regions of high critical R(s) were defined and graphically verified. The optimum method was selected based on the best resolution separation in the shortest run time for a synthetic mixture, followed by application on two pharmaceutical preparations available in the market. The predicted retention times of all peaks were found to be in good match with the virtual ones. In conclusion, the presented report offers an accurate determination of the design space for critical resolution in the analysis of water-soluble vitamins by HPLC, which would help the regulatory authorities to judge the validity of presented analytical methods for approval. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Selection of optimum ionic liquid solvents for flavonoid and phenolic acids extraction

NASA Astrophysics Data System (ADS)

Rahman, N. R. A.; Yunus, N. A.; Mustaffa, A. A.

2017-06-01

Phytochemicals are important in improving human health with their functions as antioxidants, antimicrobials and anticancer agents. However, the quality of phytochemicals extract relies on the efficiency of extraction process. Ionic liquids (ILs) have become a research phenomenal as extraction solvent due to their unique properties such as unlimited range of ILs, non-volatile, strongly solvating and may become either polarity. In phytochemical extraction, the determination of the best solvent that can extract highest yield of solute (phytochemical) is very important. Therefore, this study is conducted to determine the best IL solvent to extract flavonoids and phenolic acids through a property prediction modeling approach. ILs were selected from the imidazolium-based anion for alkyl chains ranging from ethyl > octyl and cations consisting of Br, Cl, [PF6], BF4], [H2PO4], [SO4], [CF3SO3], [TF2N] and [HSO4]. This work are divided into several stages. In Stage 1, a Microsoft Excel-based database containing available solubility parameter values of phytochemicals and ILs including its prediction models and their parameters has been established. The database also includes available solubility data of phytochemicals in IL, and activity coefficient models, for solid-liquid phase equilibrium (SLE) calculations. In Stage 2, the solubility parameter values of the flavonoids (e.g. kaempferol, quercetin and myricetin) and phenolic acids (e.g. gallic acid and caffeic acid) are determined either directly from database or predicted using Stefanis and Marrero-Gani group contribution model for the phytochemicals. A cation-anion contribution model is used for IL. In Stage 3, the amount of phytochemicals extracted can be determined by using SLE relationship involving UNIFAC-IL model. For missing parameters (UNIFAC-IL), they are regressed using available solubility data. Finally, in Stage 4, the solvent candidates are ranked and five ILs, ([OMIM] [TF2N], [HeMIM] [TF2N], [HMIM] [TF2N], [HeMIM] [CF3SO3] and [HMIM] [CF3SO3]) were identified and selected.

Late Holocene earthquake history of the Brigham City segment of the Wasatch fault zone at the Hansen Canyon, Kotter Canyon, and Pearsons Canyon trench sites, Box Elder County, Utah

USGS Publications Warehouse

DuRoss, Christopher B.; Personius, Stephen F.; Crone, Anthony J.; McDonald, Greg N.; Briggs, Richard W.

2012-01-01

Of the five central segments of the Wasatch fault zone (WFZ) having evidence of recurrent Holocene surface-faulting earthquakes, the Brigham City segment (BCS) has the longest elapsed time since its most recent surface-faulting event (~2.1 kyr) compared to its mean recurrence time between events (~1.3 kyr). Thus, the BCS has the highest time-dependent earthquake probability of the central WFZ. We excavated trenches at three sites––the Kotter Canyon and Hansen Canyon sites on the north-central BCS and Pearsons Canyon site on the southern BCS––to determine whether a surface-faulting earthquake younger than 2.1 ka occurred on the BCS. Paleoseismic data for Hansen Canyon and Kotter Canyon confirm that the youngest earthquake on the north-central BCS occurred before 2 ka, consistent with previous north-central BCS investigations at Bowden Canyon and Box Elder Canyon. At Hansen Canyon, the most recent earthquake is constrained to 2.1–4.2 ka and had 0.6–2.5 m of vertical displacement. At Kotter Canyon, we found evidence for two events at 2.5 ± 0.3 ka and 3.5 ± 0.3 ka, with an average displacement per event of 1.9–2.3 m. Paleoseismic data from Pearsons Canyon, on the previously unstudied southern BCS, indicate that a post-2 ka earthquake ruptured this part of the segment. The Pearsons Canyon earthquake occurred at 1.2 ± 0.04 ka and had 0.1–0.8 m of vertical displacement, consistent with our observation of continuous, youthful scarps on the southern 9 km of the BCS having 1–2 m of late Holocene(?) surface offset. The 1.2-ka earthquake on the southern BCS likely represents rupture across the Weber–Brigham City segment boundary from the penultimate Weber-segment earthquake at about 1.1 ka. The Pearsons Canyon data result in a revised length of the BCS that has not ruptured since 2 ka (with time-dependent probability implications), and provide compelling evidence of at least one segment-boundary failure and multi-segment rupture on the central WFZ. Our paleoseismic investigations of the BCS clarify the timing, displacement, and extent of late Holocene earthquakes on the segment, and importantly, confirm the long elapsed time since the most recent earthquake on most of the BCS.

Aqueous solubility and alkaline hydrolysis of the novel high explosive hexanitrohexaazaisowurtzitane (CL-20).

PubMed

Karakaya, Pelin; Sidhoum, Mohammed; Christodoulatos, Christos; Nicolich, Steve; Balas, Wendy

2005-04-11

The recently developed polycyclic nitramine CL-20 is considered as a possible replacement for the monocyclic nitramines RDX and HMX. The present study reports aqueous solubility data for CL-20, as well as the kinetic parameters for its alkaline hydrolysis with sodium hydroxide below and above its solubility limits. Aqueous solubility of CL-20 was measured in the temperature range of 4-69 degrees C and the data were fitted to a generalized solubility model. Alkaline hydrolysis experiments were conducted at 15, 20, 30 and 40 degrees C, with hydroxide concentrations ranging from 0.25 to 300 mM. Like RDX and HMX, alkaline hydrolysis of CL-20 follows second-order kinetics. CL-20 alkaline hydrolysis was found to proceed at a significantly faster rate than RDX. The temperature dependency of the second-order rate constants was evaluated using the Arrhenius model. The activation energy for CL-20 was found to be within close range of the activation energies reported for RDX and HMX.

Dissolution thermodynamics and solubility of silymarin in PEG 400-water mixtures at different temperatures.

PubMed

Shakeel, Faiyaz; Anwer, Md Khalid

2015-01-01

An isothermal method was used to measure the solubility of silymarin in binary polyethylene glycol 400 (PEG 400) + water co-solvent mixtures at temperatures T = 298.15-333.15 K and pressure p = 0.1 MPa. Apelblat and Yalkowsky models were used to correlate experimental solubility data. The mole fraction solubility of silymarin was found to increase with increasing the temperature and mass fraction of PEG 400 in co-solvent mixtures. The root mean square deviations were observed in the range of 0.48-5.32% and 1.50-9.65% for the Apelblat equation and Yalkowsky model, respectively. The highest and lowest mole fraction solubility of silymarin was observed in pure PEG 400 (0.243 at 298.15 K) and water (1.46 × 10(-5) at 298.15 K). Finally, thermodynamic parameters were determined by Van't Hoff and Krug analysis, which indicated an endothermic and spontaneous dissolution of silymarin in all co-solvent mixtures.

Determination of soluble sugar profile in rice.

PubMed

Hu, Xianqiao; Fang, Changyun; Lu, Lin; Hu, Zhanqiang; Shao, Yafang; Zhu, Zhiwei

2017-07-15

Soluble sugars in rice are the main components affecting sweetness taste of rice. In this paper, an accurate, precise and rapid method for simultaneous determination of multi soluble sugars in rice by using ion chromatography equipped with pulsed amperometric detector was presented. Pretreatment and parameters of ion chromatography and pulsed amperometric detector were optimized. Regression coefficients (R) of 0.9998, 1.0000, 0.9979, 0.9998 and 0.9998 were obtained for glucose, fructose, sucrose, raffinose and maltose, respectively. The recovery ranges of five sugars were 92.9-112.0% for milled rice matrix. Repeatability and reproducibility of the method were 0.8-9.7% and 1.9-7.6%, respectively. Method LODs of 3.1-34.6μgg -1 were obtained for soluble sugars in milled rice matrix. Copyright © 2017 Elsevier B.V. All rights reserved.

Application of molecular dynamics simulation to predict the compatability between water-insoluble drugs and self-associating poly(ethylene oxide)-b-poly(epsilon-caprolactone) block copolymers.

PubMed

Patel, Sarthak; Lavasanifar, Afsaneh; Choi, Phillip

2008-11-01

In the present work, molecular dynamics (MD) simulation was applied to study the solubility of two water-insoluble drugs, fenofibrate and nimodipine, in a series of micelle-forming PEO-b-PCL block copolymers with combinations of blocks having different molecular weights. The solubility predictions based on the MD results were then compared with those obtained from solubility experiments and by the commonly used group contribution method (GCM). The results showed that Flory-Huggins interaction parameters computed by the MD simulations are consistent with the solubility data of the drug/PEO-b-PCL systems, whereas those calculated by the GCM significantly deviate from the experimental observation. We have also accounted for the possibility of drug solubilization in the PEO block of PEO-b-PCL.

A screening strategy for heterologous protein expression in Escherichia coli with the highest return of investment.

PubMed

Pacheco, Benny; Crombet, Lissete; Loppnau, Peter; Cossar, Doug

2012-01-01

Heterologous protein expression in Escherichia coli is commonly used to obtain recombinant proteins for a variety of downstream applications. However, many proteins are not, or are only poorly, expressed in soluble form. High level expression often leads to the formation of inclusion bodies and an inactive product that needs to be refolded. By screening the solubility pattern for a set of 71 target proteins in different host-strains and varying parameters such as location of purification tag, promoter and induction temperature we propose a protocol with a success rate of 77% of clones returning a soluble protein. This protocol is particularly suitable for high-throughput screening with the goal to obtain soluble protein product for e.g. structure determination. Copyright © 2011 Elsevier Inc. All rights reserved.

Value of C-Arm Cone Beam Computed Tomography Image Fusion in Maximizing the Versatility of Endovascular Robotics.

PubMed

Chinnadurai, Ponraj; Duran, Cassidy; Al-Jabbari, Odeaa; Abu Saleh, Walid K; Lumsden, Alan; Bismuth, Jean

2016-01-01

To report our initial experience and highlight the value of using intraoperative C-arm cone beam computed tomography (CT; DynaCT(®)) image fusion guidance along with steerable robotic endovascular catheter navigation to optimize vessel cannulation. Between May 2013 and January 2015, all patients who underwent endovascular procedures using DynaCT image fusion technique along with Hansen Magellan vascular robotic catheter were included in this study. As a part of preoperative planning, relevant vessel landmarks were electronically marked in contrast-enhanced multi-slice computed tomography images and stored. At the beginning of procedure, an intraoperative noncontrast C-arm cone beam CT (syngo DynaCT(®), Siemens Medical Solutions USA Inc.) was acquired in the hybrid suite. Preoperative images were then coregistered to intraoperative DynaCT images using aortic wall calcifications and bone landmarks. Stored landmarks were then overlaid on 2-dimensional (2D) live fluoroscopic images as virtual markers that are updated in real-time with C-arm, table movements and image zoom. Vascular access and robotic catheter (Magellan(®), Hansen Medical) was setup per standard. Vessel cannulation was performed based on electronic virtual markers on live fluoroscopy using robotic catheter. The impact of 3-dimensional (3D) image fusion guidance on robotic vessel cannulation was evaluated retrospectively, by assessing quantitative parameters like number of angiograms acquired before vessel cannulation and qualitative parameters like accuracy of vessel ostium and centerline markers. All 17 vessels were cannulated successfully in 14 patients' attempted using robotic catheter and image fusion guidance. Median vessel diameter at origin was 5.4 mm (range, 2.3-13 mm), whereas 12 of 17 (70.6%) vessels had either calcified and/or stenosed origin from parent vessel. Nine of 17 vessels (52.9 %) were cannulated without any contrast injection. Median number of angiograms required before cannulation was 0 (range, 0-2). On qualitative assessment, 14 of 15 vessels (93.3%) had grade = 1 accuracy (guidewire inside virtual ostial marker). Fourteen of 14 vessels had grade = 1 accuracy (virtual centerlines that matched with the actual vessel trajectory during cannulation). In this small series, the experience of using DynaCT image fusion guidance together with a steerable endovascular robotic catheter indicates that such image fusion strategies can enhance intraoperative 2D fluoroscopy by bringing preoperative 3D information about vascular stenosis and/or calcification, angulation, and take off from main vessel thereby facilitating ultimate vessel cannulation. Copyright © 2016 Elsevier Inc. All rights reserved.

A simple thermodynamic approach to predict responses from polymer-coated quartz crystal microbalance sensors exposed to organic vapors.

PubMed

Palmas, P; Klingenfus, J; Vedeau, B; Girard, E; Montmeat, P; Hairault, L; Pradier, C M; Méthivier, C

2013-10-15

As of lately, the demand for developing artificial sensors with improved capabilities for the detection of explosives, toxics or drugs has increased. Ideally, sensor devices should provide high sensitivity and give a response that is specific to a given target molecule without being influenced by possible interfering molecules in the atmosphere. These properties strongly depend on the structure of the chemical compound used as a sensitive material. It is thus crucial to select the right compound and this step would be facilitated with the aid of predictive tools. The present investigations have been focused on a family of functionalized polysiloxane polymers deposited on a QCM device, producing only weak interactions compatible with reversible sensors. The quartz frequency variation at equilibrium has been linked to the partition coefficient that was evaluated using a thermodynamic description of the adsorption process. We have shown that the relative responses of two polymers can be directly determined from the Gibbs free enthalpy of mixing as determined from NMR measurements performed on neat liquid mixtures. An equivalence of this term-including both enthalpy and entropy contributions-to the energy interaction term calculated using Hansen solubility coefficients, has been demonstrated previously. These results constitute a basis for the development of a numerical program for calculating equilibrium sensor responses. For small molecules, the adsorption kinetics can be easily accounted for by a Fick diffusion coefficient estimated from the Van der Waals volume. Copyright © 2013 Elsevier B.V. All rights reserved.

Structural characterization of agonist and antagonist-bound acetylcholine-binding protein from Aplysia californica.

PubMed

Hansen, Scott B; Sulzenbacher, Gerlind; Huxford, Tom; Marchot, Pascale; Bourne, Yves; Taylor, Palmer

2006-01-01

Nicotinic acetylcholine receptors (nAChRs) are well-characterized allosteric transmembrane proteins involved in the rapid gating of ions elicited by ACh. These receptors belong to the Cys-loop superfamily of ligand-gated ion channels, which also includes GABAA and GABAC, 5-HT3, and glycine receptors. The nAChRs are homo- or heteromeric pentamers of structurally related subunits that encompass an extracellular N-terminal ligand-binding domain, four transmembrane-spanning regions that form the ion channel, and an extended intracellular region between spans 3 and 4. Ligand binding triggers conformational changes that are transmitted to the transmembrane-spanning region, leading to gating and changes in membrane potential. The four transmembrane spans on each of the five subunits create a substantial region of hydrophobicity that precludes facile crystallization of this protein. However the freshwater snail, Lymnaea stagnalis, produces a soluble homopentameric protein, termed the ACh-binding protein (AChBP), which binds ACh (Smit et al., 2001). Its structure was determined recently (Brejc et al., 2001) at high resolution, revealing the structural scaffold for nAChR, and has become a functional and structural surrogate of the nAChR ligand-binding domain. We have characterized an AChBP from Aplysia californica and determined distinct ligand-binding properties when compared to those of L. stagnalis, including ligand specificity for the nAChR alpha7 subtype-specific alpha-conotoxin ImI (Hansen et al., 2004).

ErbB2 Trafficking and Signaling in Human Vestibular Schwannomas

DTIC Science & Technology

2010-10-01

International Conference on Vestibular Schwannomas and Other CPA Lesions, Barcelona , Spain, June 2007 Brown, KD, Clark, J, Hansen MR. Differential...modified Eagle’s medium (DMEM) with N2 supplements (Sigma, St. Louis, MO), bovine insulin (Sigma, 10 g/mL) and 10% fetal calf serum ( FCS ). The medium

ERbB2 Trafficking and Signaling in Human Vestibular Schwannomas

DTIC Science & Technology

2011-10-01

International Conference on Vestibular Schwannomas and Other CPA Lesions, Barcelona , Spain, June 2007 8 Brown, KD, Clark, J, Hansen MR. Differential...Louis, MO), bovine insulin (Sigma, 10 g/mL) and 10% fetal calf serum ( FCS ). The medium was exchanged 1 to 2 days later and the cells were

GLCF: Publications

Science.gov Websites

Services Contact Site Map Go Publications 2017 Che, X., Feng, M., Sexton, J. O., Channan, S., Yang, Y ., Choate, D., Stoner, D., Arundel, T., Hansen, J., Theimer, T., Holton, B., Jansen, B., Sexton, J.O. and successful acquisitions. Wildlife Society Bulletin. Brinck, K., Fischer, R., Groeneveld, J., Lehmann, S., De

Response to Hansen: Economic Pressures, Not Science, Undermine Humanistic Counseling

ERIC Educational Resources Information Center

Leibert, Todd W.

2012-01-01

The author contends that it was economic interests, not reductionist scientific methods, that displaced the humanities as the basis for counseling profession. Attacking scientific methods may inadvertently marginalize humanistic counselors. Instead, science in counseling should be viewed more broadly and thereby support the humanities as a basis…

131. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN ...

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

131. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN FALLS COUNTY, SOUTH OF HANSEN, IDAHO; INLET SIDE OF LOW LINE CANAL, WEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

IRBM in Unitary Plan Wind Tunnel

NASA Image and Video Library

1957-09-07

L57-700 In the reentry flight path of this nose cone model of a Jupiter Intermediate range ballistic missile (IRBM) was tested in the Unitary Plan Wind Tunnel. Photograph published in Engineer in Charge: A History of the Langley Aeronautical Laboratory, 1917-1958 by James R. Hansen. Page 475.

Community Partners' Perspectives of Community-University Partnerships that Support Service-Learning

ERIC Educational Resources Information Center

Witchger Hansen, Anne Marie

2010-01-01

Community partner voices are important to understand because they provide the contexts in which occupational therapy students meet course objectives by applying clinical reasoning theory and developing clinical reasoning skills in a natural context (Witchger-Hansen et al., 2007; Provident, et al., 2011). To sustain these community-university…

133. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN ...

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

133. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN FALLS COUNTY, SOUTH OF HANSEN, IDAHO; VIEW OF OUTLET SIDE OF LOW LINE GATES. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Problems of Practice: Canadian Cases in Leadership and Policy

ERIC Educational Resources Information Center

Pollock, Katina; Ryan, James

2013-01-01

One way to support aspiring and current administrators is through the use of case study teaching (Barnes, Christensen, & Hansen, 1994). Using case studies as a teaching and learning tool helps bring real-life situations into principal preparation and support programs. Case study approaches provide students with time to interrogate contemporary…

Operational Planning with Uncertain and Ambiguous Information: Command and Control and the Natural Environment

DTIC Science & Technology

2011-06-01

1974). In the present work, we do not modify the collaborative structure but instead examine the changes in media richness ( Daft & Lengel, 1986) for...Postgraduate School) and Dr. Jim Hansen (Naval Research Laboratory) regarding weather forecasting, risk and uncertainty. References Daft , R.L. and

Hypersonic Glider Model in Full Scale Tunnel 1957

NASA Image and Video Library

1957-09-07

L57-1439 A model based on Langley s concept of a hypersonic glider was test flown on an umbilical cord inside the Full Scale Tunnel in 1957. Photograph published in Engineer in Charge: A History of the Langley Aeronautical Laboratory, 1917-1958 by James R. Hansen. Page 374.

CONTINUOUS BLACK CARBON MEASUREMENTS INDOORS AND OUTDOORS AT AN OCCUPIED HOUSE FOR ONE YEAR

EPA Science Inventory

Black carbon is one of the components of particulate matter, and is of importance because the only known source of aerosol black carbon in the atmosphere is the combustion of carbonaceous fuels (Hansen, 1997). Polyaromatic hydrocarbons (PAH) formed in the combustion process ar...

Genetics Home Reference: 17q12 duplication

MedlinePlus

... books/NBK344340/ Citation on PubMed Mefford HC, Clauin S, Sharp AJ, Moller RS, Ullmann R, Kapur R, Pinkel D, Cooper GM, ... 10.1002/ajmg.a.37848. Citation on PubMed Sharp AJ, Hansen S, Selzer RR, Cheng Z, Regan R, Hurst JA, Stewart H, Price SM, Blair E, ...

38 CFR 3.551 - Reduction because of hospitalization.

Code of Federal Regulations, 2011 CFR

2011-07-01

... veteran is hospitalized for Hansen's disease. The provisions of this section apply to initial periods of... Affairs institution or domiciliary or at Department of Veterans Affairs expense. (Authority: 38 U.S.C... release shall be considered a new admission. (Authority: 38 U.S.C. 5503(a)) (c) Section 306 pension. (1...

38 CFR 3.551 - Reduction because of hospitalization.

Code of Federal Regulations, 2010 CFR

2010-07-01

... veteran is hospitalized for Hansen's disease. The provisions of this section apply to initial periods of... Affairs institution or domiciliary or at Department of Veterans Affairs expense. (Authority: 38 U.S.C... release shall be considered a new admission. (Authority: 38 U.S.C. 5503(a)) (c) Section 306 pension. (1...

38 CFR 3.551 - Reduction because of hospitalization.

Code of Federal Regulations, 2014 CFR

2014-07-01

... veteran is hospitalized for Hansen's disease. The provisions of this section apply to initial periods of... Affairs institution or domiciliary or at Department of Veterans Affairs expense. (Authority: 38 U.S.C... release shall be considered a new admission. (Authority: 38 U.S.C. 5503(a)) (c) Section 306 pension. (1...

38 CFR 3.551 - Reduction because of hospitalization.

Code of Federal Regulations, 2013 CFR

2013-07-01

... veteran is hospitalized for Hansen's disease. The provisions of this section apply to initial periods of... Affairs institution or domiciliary or at Department of Veterans Affairs expense. (Authority: 38 U.S.C... release shall be considered a new admission. (Authority: 38 U.S.C. 5503(a)) (c) Section 306 pension. (1...

38 CFR 3.551 - Reduction because of hospitalization.

Code of Federal Regulations, 2012 CFR

2012-07-01

... veteran is hospitalized for Hansen's disease. The provisions of this section apply to initial periods of... Affairs institution or domiciliary or at Department of Veterans Affairs expense. (Authority: 38 U.S.C... release shall be considered a new admission. (Authority: 38 U.S.C. 5503(a)) (c) Section 306 pension. (1...

40 CFR Appendix to Part 246 - Recommended Bibliography

Code of Federal Regulations, 2011 CFR

2011-07-01

... Belknap, M. Paper recycling: a business perspective. Subcommittee on Solid Waste, New York Chamber of... Publication SW-155. Washington, U.S. Government Printing Office, 1975. 26 p. Hansen, P. Solid waste recycling... Printing Office, 1973. 284 p. Lingle, S. A. Paper recycling in the United States. Washington, U.S...

40 CFR Appendix to Part 246 - Recommended Bibliography

Code of Federal Regulations, 2010 CFR

2010-07-01

... Belknap, M. Paper recycling: a business perspective. Subcommittee on Solid Waste, New York Chamber of... Publication SW-155. Washington, U.S. Government Printing Office, 1975. 26 p. Hansen, P. Solid waste recycling... Printing Office, 1973. 284 p. Lingle, S. A. Paper recycling in the United States. Washington, U.S...

40 CFR Appendix to Part 246 - Recommended Bibliography

Code of Federal Regulations, 2012 CFR

2012-07-01

... Belknap, M. Paper recycling: a business perspective. Subcommittee on Solid Waste, New York Chamber of... Publication SW-155. Washington, U.S. Government Printing Office, 1975. 26 p. Hansen, P. Solid waste recycling... Printing Office, 1973. 284 p. Lingle, S. A. Paper recycling in the United States. Washington, U.S...

40 CFR Appendix to Part 246 - Recommended Bibliography

Code of Federal Regulations, 2013 CFR

2013-07-01

... Belknap, M. Paper recycling: a business perspective. Subcommittee on Solid Waste, New York Chamber of... Publication SW-155. Washington, U.S. Government Printing Office, 1975. 26 p. Hansen, P. Solid waste recycling... Printing Office, 1973. 284 p. Lingle, S. A. Paper recycling in the United States. Washington, U.S...

40 CFR Appendix to Part 246 - Recommended Bibliography

Code of Federal Regulations, 2014 CFR

2014-07-01

... Belknap, M. Paper recycling: a business perspective. Subcommittee on Solid Waste, New York Chamber of... Publication SW-155. Washington, U.S. Government Printing Office, 1975. 26 p. Hansen, P. Solid waste recycling... Printing Office, 1973. 284 p. Lingle, S. A. Paper recycling in the United States. Washington, U.S...

Rejoinder to Guterman, Martin, and Kopp

ERIC Educational Resources Information Center

Hansen, James T.

2012-01-01

In their reply to the author's keystone article (Hansen, 2012), Guterman, Martin, and Kopp (2012) charge that the author's integrative framework was not sufficiently integrative. They also argue that his proposal results in logical contradictions and the mind-body problem. The author responds by noting that his proposal fully integrates the…

Lifelong Learning: Policies, Practices, and Programs.

ERIC Educational Resources Information Center

Hatton, Michael J., Ed.

The 26 articles in this book focus on lifelong learning policies, practices, and programs in 13 Asia Pacific countries. The following papers are included: "Half a Revolution: A Brief Survey of Lifelong Learning in New Zealand" (P. Methven and J. Hansen); "HRD in a Multicultural Workplace: The Need for Lifelong Learning" (M.…

42 CFR 32.88 - Examinations and treatment.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Examinations and treatment. 32.88 Section 32.88... Hansen's Disease § 32.88 Examinations and treatment. Patients will be provided necessary clinical examinations which may be required for the diagnosis of primary or secondary conditions, and such treatment as...

Bottom-up approach to fabricate nanostructured thin films from colloidal nanocrystal precursors

NASA Astrophysics Data System (ADS)

Shaw, Santosh

Control over microstructures at the nanoscale (<100nm) still seems challenging due to, among other things, the stochastic nature of nucleation in the bulk phase. The densification of assemblies of ligand-capped nanocrystals (colloidal nanocrystal assemblies, CNAs) could bypass this challenge that limits our control over the nanostructure and, therefore, the properties of materials. However, the removal of the ligands and the cracking that follows it are the two critical hurdles that have been stymieing this approach. We show that low-pressure plasma processing can effectively remove ligands from CNAs (down to 0.6 at.% of carbon which can be accounted for adventitious carbon) without harming the properties of the inorganic cores of the nanoparticles and the structure of CNAs. The cracking of CNAs is correlated with the structure of the CNAs, which can be controlled and easily predicted by Hansen solubility parameters of solvent in which the nanoparticles are dispersed. While a fully solvated ligand shell leads to the formation of close-packed ordered CNAs - which cracked after self-assembly or ligand removal - a partially solvated one results in interdigitation of the ligand shell yielding disordered CNAs, which remained crack-free after ligand removal and sintering up to a critical cracking thickness of 440nm. The process is demonstrated with particles of different compositions, ligands, sizes, shapes, as well as with binary systems. These findings allowed for the fabrication of cm2 crack-free, phase-pure polycrystalline films with tunable, near-monodisperse grain sizes using CNAs as precursors. We observed electrical conductivities of PbS films produced by this approach over 1 cm to be 1.370 S/cm which is comparable to those of bulk crystal. This conductivity value is remarkable considering the fact that the typical porosity in fully processed CNAs is around 40%. We simultaneously answered the fundamental question that how microstructure of CNAs evolves during ligand removal and studied its effect on microstructure related physical properties, e.g., mechanical properties. We further demonstrated that our bottom-up approach can control the grain boundary composition in the final materials by controlling the chemical structure and composition of the ligands and the characteristics of the plasma. We show that with our unprecedented control on grain boundary composition, we can selectively modify grain growth mechanisms, control phase transitions, and affect mechanical properties. By understanding the interaction of plasma species with CNAs and the mass transport in the system, we were able to accelerate the plasma etching rate by more than an order of magnitude. Finally, we demonstrate the applicability of our approach in developing an optics-free lithography in which CNAs are used as resist and as an active material. By selectively masking the interaction of plasma with CNAs with a hard mask we could change the solubility of the exposed regions. This patterning technology can pattern materials which are hard to pattern by traditional inorganic etching based pattern transfer (example, copper, gold).

Effect of salts on the solubility of ionic liquids in water: experimental and electrolyte Perturbed-Chain Statistical Associating Fluid Theory†

PubMed Central

Mohammad, Sultan; Schleinitz, Miko; Coutinhoa, João A. P.; Freire, Mara G.

2016-01-01

Due to scarce available experimental data, as well as due to the absence of predictive models, the influence of salts on the solubility of ionic liquids (ILs) in water is still poorly understood. To this end, this work addresses the solubility of the IL 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C4C1im][NTf2]), at 298.15 K and 0.1 MPa, in aqueous salt solutions (from 0.1 to 1.5 mol kg−1). At salt molalities higher than 0.2 mol kg−1, all salts caused salting-out of [C4C1im][NTf2] from aqueous solution with their strength decreasing in the following order: Al2(SO4)3 > ZnSO4 > K3C6H5O7 > KNaC4H4O6 > K3PO4 > Mg(CH3CO2)2 > K2HPO4 > MgSO4 > KH2PO4 > KCH3CO2. Some of these salts lead however to the salting-in of [C4C1im][NTf2] in aqueous medium at salt molalities lower than 0.20 mol kg−1. To attempt the development of a model able to describe the salt effects, comprising both the salting-in and salting-out phenomena observed, the electrolyte Perturbed-Chain Statistical Associating Fluid Theory (ePC-SAFT) was applied using ion-specific parameters. The gathered experimental data was modelled using ePC-SAFT parameters complemented by fitting a single binary parameter between K+ and the IL-ions to the IL solubility in K3PO4 aqueous solutions. Based on this approach, the description of anion-specific salting-out effects of the remaining potassium salts was found to be in good agreement with experimental data. Remarkably, ePC-SAFT is even able to predict the salting-in effect induced by K2HPO4, based on the single K+/IL-ions binary parameter which was fitted to an exclusively salting-out effect promoted by K3PO4. Finally, ePC-SAFT was applied to predict the influence of other sodium salts on the [C4C1im][NTf2] solubility in water, with experimental data taken from literature, leading to an excellent description of the liquid–liquid phase behaviour. PMID:26575280

Supramolecular Assembly of Tripodal Trisamides

NASA Astrophysics Data System (ADS)

Feng, Li

2010-03-01

A series of tripodal trisamide compounds have been synthesized from tris(2-aminoethyl)amine (TREN) by condensation with different acid chlorides. Gelation of organic solvents with these compounds was investigated as a function of concentration and solvent solubility parameter. Compounds made with linear acid chlorides were poor gelators. A gelator made with 2-ethylbutyryl chloride (TREN-EB) was an excellent gelator for many organic solvents. It was found that the minimum gelation concentration of TREN-EB increased with increasing solubility parameter of the solvent. Thin films samples were prepared by spin-coating mixtures of TREN-EB and a poly(acrylate). Scanning force microscopy measurements showed that TREN-EB formed nanofibrillar network structures. In addition a dependence of the network morphology on the casting solvent was found.

Preparation of nanoparticles of poorly water-soluble antioxidant curcumin by antisolvent precipitation methods

NASA Astrophysics Data System (ADS)

Kakran, Mitali; Sahoo, Nanda Gopal; Tan, I.-Lin; Li, Lin

2012-03-01

The objective of this study was to enhance the solubility and dissolution rate of a poorly water-soluble antioxidant, curcumin, by fabricating its nanoparticles with two methods: antisolvent precipitation with a syringe pump (APSP) and evaporative precipitation of nanosuspension (EPN). For APSP, process parameters like flow rate, stirring speed, solvent to antisolvent (SAS) ratio, and drug concentration were investigated to obtain the smallest particle size. For EPN, factors like drug concentration and the SAS ratio were examined. The effects of these process parameters on the supersaturation, nucleation, and growth rate were studied and optimized to obtain the smallest particle size of curcumin by both the methods. The average particle size of the original drug was about 10-12 μm and it was decreased to a mean diameter of 330 nm for the APSP method and to 150 nm for the EPN method. Overall, decreasing the drug concentration or increasing the flow rate, stirring rate, and antisolvent amount resulted in smaller particle sizes. Differential scanning calorimetry studies suggested lower crystallinity of curcumin particles fabricated. The solubility and dissolution rates of the prepared curcumin particles were significantly higher than those the original curcumin. The antioxidant activity, studied by the DPPH free radical-scavenging assay, was greater for the curcumin nanoparticles than the original curcumin. This study demonstrated that both the methods can successfully prepare curcumin into submicro to nanoparticles. However, drug particles prepared by EPN were smaller than those by APSP and hence, showed the slightly better solubility, dissolution rate, and antioxidant activity than the latter.

Differential molar heat capacities to test ideal solubility estimations.

PubMed

Neau, S H; Bhandarkar, S V; Hellmuth, E W

1997-05-01

Calculation of the ideal solubility of a crystalline solute in a liquid solvent requires knowledge of the difference in the molar heat capacity at constant pressure of the solid and the supercooled liquid forms of the solute, delta Cp. Since this parameter is not usually known, two assumptions have been used to simplify the expression. The first is that delta Cp can be considered equal to zero; the alternate assumption is that the molar entropy of fusion, delta Sf, is an estimate of delta Cp. Reports claiming the superiority of one assumption over the other, on the basis of calculations done using experimentally determined parameters, have appeared in the literature. The validity of the assumptions in predicting the ideal solubility of five structurally unrelated compounds of pharmaceutical interest, with melting points in the range 420 to 470 K, was evaluated in this study. Solid and liquid heat capacities of each compound near its melting point were determined using differential scanning calorimetry. Linear equations describing the heat capacities were extrapolated to the melting point to generate the differential molar heat capacity. Linear data were obtained for both crystal and liquid heat capacities of sample and test compounds. For each sample, ideal solubility at 298 K was calculated and compared to the two estimates generated using literature equations based on the differential molar heat capacity assumptions. For the compounds studied, delta Cp was not negligible and was closer to delta Sf than to zero. However, neither of the two assumptions was valid for accurately estimating the ideal solubility as given by the full equation.

Application of physiologically based absorption modeling to formulation development of a low solubility, low permeability weak base: mechanistic investigation of food effect.

PubMed

Zhang, Hefei; Xia, Binfeng; Sheng, Jennifer; Heimbach, Tycho; Lin, Tsu-Han; He, Handan; Wang, Yanfeng; Novick, Steven; Comfort, Ann

2014-04-01

Physiologically based pharmacokinetic (PBPK) modeling has been broadly used to facilitate drug development, hereby we developed a PBPK model to systematically investigate the underlying mechanisms of the observed positive food effect of compound X (cpd X) and to strategically explore the feasible approaches to mitigate the food effect. Cpd X is a weak base with pH-dependent solubility; the compound displays significant and dose-dependent food effect in humans, leading to a nonadherence of drug administration. A GastroPlus Opt logD Model was selected for pharmacokinetic simulation under both fasted and fed conditions, where the biopharmaceutic parameters (e.g., solubility and permeability) for cpd X were determined in vitro, and human pharmacokinetic disposition properties were predicted from preclinical data and then optimized with clinical pharmacokinetic data. A parameter sensitivity analysis was performed to evaluate the effect of particle size on the cpd X absorption. A PBPK model was successfully developed for cpd X; its pharmacokinetic parameters (e.g., C max, AUCinf, and t max) predicted at different oral doses were within ±25% of the observed mean values. The in vivo solubility (in duodenum) and mean precipitation time under fed conditions were estimated to be 7.4- and 3.4-fold higher than those under fasted conditions, respectively. The PBPK modeling analysis provided a reasonable explanation for the underlying mechanism for the observed positive food effect of the cpd X in humans. Oral absorption of the cpd X can be increased by reducing the particle size (<100 nm) of an active pharmaceutical ingredient under fasted conditions and therefore, reduce the cpd X food effect correspondingly.

Influence of Curing Mode on the Surface Energy and Sorption/Solubility of Dental Self-Adhesive Resin Cements

PubMed Central

Kim, Hyun-Jin; Bagheri, Rafat; Kim, Young Kyung; Son, Jun Sik; Kwon, Tae-Yub

2017-01-01

This study investigated the influence of curing mode (dual- or self-cure) on the surface energy and sorption/solubility of four self-adhesive resin cements (SARCs) and one conventional resin cement. The degree of conversion (DC) and surface energy parameters including degree of hydrophilicity (DH) were determined using Fourier transform infrared spectroscopy and contact angle measurements, respectively (n = 5). Sorption and solubility were assessed by mass gain or loss after storage in distilled water or lactic acid for 60 days (n = 5). A linear regression model was used to correlate between the results (%DC vs. DH and %DC/DH vs. sorption/solubility). For all materials, the dual-curing consistently produced significantly higher %DC values than the self-curing (p < 0.05). Significant negative linear regressions were established between the %DC and DH in both curing modes (p < 0.05). Overall, the SARCs showed higher sorption/solubility values, in particular when immersed in lactic acid, than the conventional resin cement. Linear regression revealed that %DC and DH were negatively and positively correlated with the sorption/solubility values, respectively. Dual-curing of SARCs seems to lower the sorption and/or solubility in comparison with self-curing by increased %DC and occasionally decreased hydrophilicity. PMID:28772489

Effect of irradiation on the parameters that influence quality characteristics of raw turkey breast meat

NASA Astrophysics Data System (ADS)

Feng, Xi; Moon, Sun Hee; Lee, Hyun Yong; Ahn, Dong Uk

2017-01-01

This study was designed to elucidate the mechanisms of quality changes in raw turkey breast meat by irradiation. Raw turkey breast meat was irradiated at 0 kGy, 1.5 kGy, 3.0 kGy and 4.5 kGy, and changes in quality parameters including color, lipid and protein oxidation, and off-odor volatiles were determined. Irradiation accelerated lipid and protein oxidation, and increased redness in raw turkey breast meat. However, irradiation had less effect on the volatile profiles of salt-soluble muscle extract than water-soluble muscle extract because the primary radiolytic product from water (hydroxyl radical) had higher chances to react with the water-soluble molecules nearby. The radiolytic degradation products from sulfur-containing amino acids and aldehydes from lipid oxidation were two major volatile compounds responsible for the off-odor of irradiated raw turkey breast meat. Dimethyl disulfide was found only in irradiated raw turkey breast meat, and the amount of dimethyl disulfide linearly increased as the irradiation dose increased, indicating that this compound can be used as a marker for irradiate meat.

Improvement of the photovoltaic parameters of perovskite solar cells using a reduced-graphene-oxide-modified titania layer and soluble copper phthalocyanine as a hole transporter.

PubMed

Nouri, Esmaiel; Mohammadi, Mohammad Reza; Xu, Zong-Xiang; Dracopoulos, Vassilios; Lianos, Panagiotis

2018-01-24

Functional perovskite solar cells can be made by using a simple, inexpensive and stable soluble tetra-n-butyl-substituted copper phthalocyanine (CuBuPc) as a hole transporter. In the present study, TiO 2 /reduced graphene oxide (T/RGO) hybrids were synthesized via an in situ solvothermal process and used as electron acceptor/transport mediators in mesoscopic perovskite solar cells based on soluble CuBuPc as a hole transporter and on graphene oxide (GO) as a buffer layer. The impact of the RGO content on the optoelectronic properties of T/RGO hybrids and on the solar cell performance was studied, suggesting improved electron transport characteristics and photovoltaic parameters. An enhanced electron lifetime and recombination resistance led to an increase in the short circuit current density, open circuit voltage and fill factor. The device based on a T/RGO mesoporous layer with an optimal RGO content of 0.2 wt% showed 22% higher photoconversion efficiency and higher stability compared with pristine TiO 2 -based devices.

Evaluation of antioxidant capacity in coffees marketed in Colombia: Relationship with the extent of non-enzymatic browning.

PubMed

Contreras-Calderón, José; Mejía-Díaz, Diana; Martínez-Castaño, Marcela; Bedoya-Ramírez, Daniel; López-Rojas, Natalia; Gómez-Narváez, Faver; Medina-Pineda, Yaqueline; Vega-Castro, Oscar

2016-10-15

Fifty-eight samples of commercial Colombian coffee with different characteristics (soluble, ground, decaffeinated, etc) were evaluated for antioxidant capacity (AC) (ABTS and FRAP), total soluble phenolics (TP), browning index (BI), color parameters (L(∗), a(∗), b(∗), c(∗) and h(∗)), HMF and furfural. The AC in Colombian coffees was very varied (164-1000, 100.8-885.9μmol of Trolox equiv/g and 12.5-127mg gallic acid equiv/g, respectively for ABTS, FRAP and TP). AC, TP, BI, color, HMF and furfural values were higher (p<0.05) in soluble coffees than in ground ones, showing the lyophilized samples which showed the highest average values. Significant lineal correlations (p<0.05) were found between AC and color parameters, BI, HMF. No significant (p<0.05) differences in the AC between the different types of coffee were found. This work confirms the direct relationship between the rate of non-enzymatic browning and antioxidant capacity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of the chemical quality traits of soybean seeds, as related to sensory attributes of soymilk.

PubMed

Ma, Lei; Li, Bin; Han, Fenxia; Yan, Shurong; Wang, Lianzheng; Sun, Junming

2015-04-15

The soybean seed chemical quality traits (including protein content, oil content, fatty acid composition, isoflavone content, and protein subunits), soymilk chemical character (soluble solid), and soymilk sensory attributes were evaluated among 70 genotypes to determine the correlation between seed chemical quality traits and soymilk sensory attributes. Six sensory parameters (i.e., soymilk aroma, smoothness in the mouth, thickness in the mouth, sweetness, colour and appearance, and overall acceptability) and a seven-point hedonic scale for each parameter were developed. Significant positive correlations were observed between overall acceptability and the other five evaluation parameters, suggesting that overall acceptability is an ideal parameter for evaluating soymilk flavour. The soymilk sensory attributes were significantly positively correlated with the characteristics of the glycinin (11S)/beta-conglycinin (7S) protein ratio, soluble solid, and oil content but negatively correlated with glycitein and protein content. Our results indicated that soymilk sensory attributes could be improved by selecting the desirable seed chemical quality traits in practical soybean breeding programs. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Solubility and modeling acid-base properties of adrenaline in NaCl aqueous solutions at different ionic strengths and temperatures.

PubMed

Bretti, Clemente; Cigala, Rosalia Maria; Crea, Francesco; De Stefano, Concetta; Vianelli, Giuseppina

2015-10-12

Solubility and acid-base properties of adrenaline were studied in NaCl aqueous solutions at different ionic strengths (0